Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),a...Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),are essential due to the limitations of simpler security measures,such as cryptography and firewalls.Due to their compact nature and low energy reserves,wireless networks present a significant challenge for security procedures.The features of small cells can cause threats to the network.Network Coding(NC)enabled small cells are vulnerable to various types of attacks.Avoiding attacks and performing secure“peer”to“peer”data transmission is a challenging task in small cells.Due to the low power and memory requirements of the proposed model,it is well suited to use with constrained small cells.An attacker cannot change the contents of data and generate a new Hashed Homomorphic Message Authentication Code(HHMAC)hash between transmissions since the HMAC function is generated using the shared secret.In this research,a chaotic sequence mapping based low overhead 1D Improved Logistic Map is used to secure“peer”to“peer”data transmission model using lightweight H-MAC(1D-LM-P2P-LHHMAC)is proposed with accurate intrusion detection.The proposed model is evaluated with the traditional models by considering various evaluation metrics like Vector Set Generation Accuracy Levels,Key Pair Generation Time Levels,Chaotic Map Accuracy Levels,Intrusion Detection Accuracy Levels,and the results represent that the proposed model performance in chaotic map accuracy level is 98%and intrusion detection is 98.2%.The proposed model is compared with the traditional models and the results represent that the proposed model secure data transmission levels are high.展开更多
Small cells have been regarded as an appealing technique to boost resource reuse ratio. On the other hand, their large-scale and self-organised tendency would complicate the interference environment of mobile networks...Small cells have been regarded as an appealing technique to boost resource reuse ratio. On the other hand, their large-scale and self-organised tendency would complicate the interference environment of mobile networks. Meanwhile, traffic class is booming in recent years, which leads to higher demand for net- work designers on Quality of Service (QoS) provision, and therefore users' diverse re- quirements may not be guaranteed in sucff'an interference limited scenario. To maximise the number of users with QoS demands as well as resource reuse ratio, we formulate the resource allocation problem into a multi-objective l0 norm form. It is shown to be NP hard, and an iterative method is employed to approach the optimal solution. Because of its limit of being not adaptive to large-scale networks, we also design a heuristic method based on chordal graph, which, however, could result in per- formance loss when the size of networks is small. Finally, by combining these two meth- ods, we devise a hybrid algorithm such that the allocation performs both efficiently and effectively. Simulation results illustrate the performance of our proposed methods in terms of outage probability and resource reuse ratio.展开更多
With the proliferation of small and mini drones, Drone Small Cells(DSCs) can cooperative multiple drones to provide communication service for ground users as emergency means or supplementary ones of traditional terres...With the proliferation of small and mini drones, Drone Small Cells(DSCs) can cooperative multiple drones to provide communication service for ground users as emergency means or supplementary ones of traditional terrestrial cellular networks. In this paper, we study the fundamental problem of optimizing the deployment density of DSCs to achieve the maximum coverage performance. Most related works do not consider cumulative inter-cell interference when studying the coverage performance of DSCs. First, we derive an approximate and closed-form expression of the cumulative inter-cell interference which comes from both probabilistic Line-of-Sight(Lo S) and Non-Line-of-Sight(NLo S) links. Then, we analyze the coverage performance of DSCs and derive the transcendental function of optimal deployment density to obtain the maximum coverage. Last, we propose an algorithm to get the optimal deployment density with low complexity. We conduct both field experiments and Matlab simulations to verify the correctness of theoretical analysis. In addition, we show the impact of some factors on the relation between the deployment density and coverage performance through extensive numerical simulations.展开更多
Switch policy is essential for small cells to properly serve variable number of users in an energy efficient way.However,frequently switching small cell base stations(SBSs) may increase the network operating cost,espe...Switch policy is essential for small cells to properly serve variable number of users in an energy efficient way.However,frequently switching small cell base stations(SBSs) may increase the network operating cost,especially when there is an nonnegligible start-up energy cost.To this end,by observing the variety of user number,we focus on the design of a switch policy which minimize the cumulative energy consumption.A given user transmission rate is guaranteed and the capability of SBSs are limited as well.According to the knowledge on user number variety,we classify the energy consumption problem into two cases.In complete information case,to minimize the cumulative energy consumption,an offline solution is proposed according to critical segments.A heuristic algorithm for incomplete information case(HAIIC) is proposed by tracking the difference of cumulative energy consumption.The upper bound of the Energy Consumption Ratio(ECR) for HAIIC is derived as well.In addition,a practical Q-learning based probabilistic policy is proposed.Simulation results show that the proposed HAIIC algorithm is able to save energy efficiently.展开更多
In order to handle the huge amounts of data transmitted through hot spots and to increase cell coverage in buildings, this paper proposes a sectored cellular network with small cells (SCNSC) embedded in each sector. T...In order to handle the huge amounts of data transmitted through hot spots and to increase cell coverage in buildings, this paper proposes a sectored cellular network with small cells (SCNSC) embedded in each sector. Two region types, sectors and variable-radius small cells are classified in an SCNSC macro cell. Because the system capacity is enhanced by using fractional frequency reuse (FFR), the overall channel bandwidth is divided into two or three frequency bands depending on whether the number of sectors in a macro cell is even or odd. For the purpose of topological evaluation on the proposed SCNSC, we build an analytical model using Markov chain theory. The performance measures include new-call blocking and handoff-call dropping probabilities, average waiting times, and normalized throughputs in each sector and its embedded small cell by varying mobile stations’ moving speeds, the number of sectors, and the radius size of an embedded small cell. From the evaluation results, it is demonstrated that adjusting either the number of sectors or the coverage of an embedded cell can satisfy different service demands.展开更多
The shrinking of cell-size brings significant changes to the wireless uplink of densely small cells (DSCs). A codebook design is proposed that utilizes the strong line of sight (LOS) chan- nel component existing i...The shrinking of cell-size brings significant changes to the wireless uplink of densely small cells (DSCs). A codebook design is proposed that utilizes the strong line of sight (LOS) chan- nel component existing in a DSC system for uplink of the DSC system. To further improve the uplink performance, the high-rank codebook is designed based on singular value decomposition (SVD) due to the unnecessary preservation of strict constant modulus in the DSC system. And according to the simulation result, the proposed codebook leads to significant sum-rate gain and appreciable block error rate (BLER) performance improvement in the DSC system.展开更多
BACKGROUND Small cell lung cancer(SCLC)is the most malignant type of lung cancer.Even in the latent period and early stage of the tumor,SCLC is prone to produce distant metastases with complex and diverse clinical man...BACKGROUND Small cell lung cancer(SCLC)is the most malignant type of lung cancer.Even in the latent period and early stage of the tumor,SCLC is prone to produce distant metastases with complex and diverse clinical manifestations.SCLC is most closely related to paraneoplastic syndrome,and some cases present as paraneoplastic peripheral neuropathy(PPN).PPN in SCLC appears early,lacks specificity,and often occurs before diagnosis of the primary tumor.It is easy to be misdiagnosed as a primary disease of the nervous system,leading to missed diagnosis and delayed diagnosis and treatment.CASE SUMMARY This paper reports two cases of SCLC with limb weakness as the first symptom.The first symptoms of one patient were rash,limb weakness,and abnormal electromyography.The patient was repeatedly referred to the hospital for limb weakness and rash for>1 year,during which time,treatment with hormones and immunosuppressants did not lead to significant improvement,and the condition gradually aggravated.The patient was later diagnosed with SCLC,and the dyskinesia did not worsen as the dermatomyositis improved after antineoplastic and hormone therapy.The second case presented with limb numbness and weakness as the first symptom,but the patient did not pay attention to it.Later,the patient was diagnosed with SCLC after facial edema caused by tumor thrombus invading the vein.However,he was diagnosed with extensive SCLC and died 1 year after diagnosis.CONCLUSION The two cases had PPN and abnormal electromyography,highlighting its correlation with early clinical indicators of SCLC.展开更多
Neurodegeneration and traumatic brain injuries are leading causes of disability and present an enormous disease burden both in terms of patient suffering and healthcare cost.Treatment of brain lesions remains as a maj...Neurodegeneration and traumatic brain injuries are leading causes of disability and present an enormous disease burden both in terms of patient suffering and healthcare cost.Treatment of brain lesions remains as a major challenge in medicine largely because of the limited regenerative capacity of the adult brain.展开更多
BACKGROUND Small cell lung carcinoma(SCLC)is highly susceptible to metastasis in the early stages of the disease.However,the stomach is an uncommon site of metastasis in SCLC,and only a few cases of this type of metas...BACKGROUND Small cell lung carcinoma(SCLC)is highly susceptible to metastasis in the early stages of the disease.However,the stomach is an uncommon site of metastasis in SCLC,and only a few cases of this type of metastasis have been reported.Therefore,SCLC gastric metastases have not been systematically characterized and are easily missed and misdiagnosed.CASE SUMMARY We report three cases of gastric metastasis from SCLC in this article.The first patient presented primarily with cough,hemoptysis,and epigastric fullness.The other two patients presented primarily with abdominal discomfort,epigastric distension,and pain.All patients underwent gastroscopy and imaging examinations.Meanwhile,the immunohistochemical results of the lesions in three patients were suggestive of small cell carcinoma.Finally,the three patients were diagnosed with gastric metastasis of SCLC through a comprehensive analysis.The three patients did not receive appropriate treatment and died within a short time.CONCLUSION Here,we focused on summarizing the characteristics of gastric metastasis of SCLC to enhance clinicians'understanding of this disease.展开更多
The effects of Shenmai injection (SMI) and am inophylline on apoptosis of sm all airway smooth muscle cells (SASMC) and the Fas/ Fas L expression in rats with papain- induced em physe- ma were investigated.Rat emphy...The effects of Shenmai injection (SMI) and am inophylline on apoptosis of sm all airway smooth muscle cells (SASMC) and the Fas/ Fas L expression in rats with papain- induced em physe- ma were investigated.Rat emphysema model was established by a single intratracheal instillation of papain.Apoptosis and Fas/Fas L expression of SASMC were detected by im munohistochemistry SABC and TU NEL assay at day1,3,5 ,7,15 ,30 after modeling,and the effect of SMI and am inophylline on them were observed.The results indicated that the Fas/Fas L expression positive rate in SASMC was2 .31± 0 .5 5 /1.2 8± 0 .4 7respectively.After a single intratracheal instillation of papain,the expression of Fas/Fas L positive rate in the placebo group was increased in a tim e- dependent manner.SMI could inhibit the expression of Fas/ Fas L ,but aminophylline couldn't. The positive rate of apoptosis in the control group was 0 .87± 0 .32 .After a single intratracheal in- stillation of papain,the SASMC apoptosis positive rate in the placebo group was increased in a tim e- dependent manner.The SASMC apoptosis rate in all groups was declined after treatment with SMI,but the effect of am inophylline was notobvious.Itwas dem onstrated thatin the patho- genesis of emphysem a Fas/Fas L played an important role in the regulation of SASMC apoptosis. SMI influenced the expression of Fas/ Fas L and declined SASMC apoptosis by inhibiting the releas- ing of inflamm atory m edia and played an im portant role in the therapy of em physema.展开更多
It is generally accepted that adult bone marrow(BM) contains both hematopoietic stem cells(HSCs) and mesenchymal stem cells (MSCs). Recently, a rare population of stem cells different from HSCs and MSCs were ide...It is generally accepted that adult bone marrow(BM) contains both hematopoietic stem cells(HSCs) and mesenchymal stem cells (MSCs). Recently, a rare population of stem cells different from HSCs and MSCs were identified in murine BM and human cord blood (CB), named as very small embryonic like(VSEL) stem cells. These cells are tiny round and CXCR4^+ Sca-1^+ Lin^- CD45^-, expressing SSEA-1/4, Oct-4 and Nanog, which have potent of differentiation into all three germ-layer lineages, such as cardiornyocytes, neural and pancreatic ceils.展开更多
Small cell lung carcinoma metastatic to the stomach,whether synchronous or metachronous,is a rare phenomenon accounting for<0.5%of lung cancers.Hence it can be overlooked by clinicians resulting in delayed diagnosi...Small cell lung carcinoma metastatic to the stomach,whether synchronous or metachronous,is a rare phenomenon accounting for<0.5%of lung cancers.Hence it can be overlooked by clinicians resulting in delayed diagnosis.This manuscript comments on Yang et al’s article which reported 3 such cases.The main diagnostic features are based on routine morphology comprised of small cells with hyperchromatic nuclei,scant cytoplasm,brisk mitoses and necrosis.This can be supplemented by immunohistochemistry demonstrating positivity for cytokeratin,thyroid transcription factor-1 and neuroendocrine markers as well as a high Ki-67 labelling index.Imaging modalities such as positron emission tomography/contrast computed tomography help to confirm lung origin and rule out the possibility of extra-pulmonary small cell carcinoma.The predominant mechanism of spread is most likely hematogeneous.Prognosis is generally poor since this represents stage 4 disease but survival can be improved by chemo/ra-diotherapy and palliative surgery in select cases.Though outcomes have not changed much in the last several decades,the recent Food and Drug Adminis-tration approval of immune checkpoint inhibitors was a significant milestone as was the delineation of small cell lung carcinoma molecular subtypes.Liquid biopsies are increasingly being used for biomarker studies in clinical trials to assess treatment response and prognosis.展开更多
Small cell lung cancer(SCLC)is a common type of primary lung cancer that contributes to approximately 15%of cases.It is closely associated with tobacco risk factors.It is also known as a type of lung cancer that has a...Small cell lung cancer(SCLC)is a common type of primary lung cancer that contributes to approximately 15%of cases.It is closely associated with tobacco risk factors.It is also known as a type of lung cancer that has a high mortality rate within a short time due to its rapid growth rate(with tumor doubling time of 30 days)and its tendency to metastasize early in the disease process.The primary sites of metastasis in SCLC are similar to those in other primary lung cancers and often include the brain,bones,adrenal glands,liver,and lymph nodes.However,there are a few clinical reports of uncommon metastases,such as gastric metastasis from SCLC.Although the incidence of this clinical presentation is very low,reported cases have generally resulted in early mortality due to inadequate treatment.The purpose of this letter is to discuss the knowledge related to gastric metastasis from SCLC and remind clinical doctors not to miss atypical symptoms,thereby providing the right attitude to improve the prognosis for these patients.展开更多
BACKGROUND Small cell lung cancer(SCLC)is a common and aggressive subtype of lung cancer.It is characterized by rapid growth and a high mortality rate.Approximately 10%of patients with SCLC present with brain metastas...BACKGROUND Small cell lung cancer(SCLC)is a common and aggressive subtype of lung cancer.It is characterized by rapid growth and a high mortality rate.Approximately 10%of patients with SCLC present with brain metastases at the time of diagnosis,which is associated with a median survival of 5 mo.This study aimed to summarize the effect of bevacizumab on the progression-free survival(PFS)and overall survival of patients with brain metastasis of SCLC.CASE SUMMARY A 62-year-old man was referred to our hospital in February 2023 because of dizziness and numbness of the right lower extremity without headache or fever for more than four weeks.The patient was diagnosed with limited-stage SCLC.He received 8 cycles of chemotherapy combined with maintenance bevacizumab therapy and achieved a PFS of over 7 mo.CONCLUSION The combination of bevacizumab and irinotecan effectively alleviated brain metastasis in SCLC and prolonged PFS.展开更多
BACKGROUND Small cell lung cancer(SCLC)exhibits a pronounced tendency for metastasis and relapse,and the acquisition of resistance to chemotherapy and radiotherapy,leading to complexity in treatment outcomes.It is cru...BACKGROUND Small cell lung cancer(SCLC)exhibits a pronounced tendency for metastasis and relapse,and the acquisition of resistance to chemotherapy and radiotherapy,leading to complexity in treatment outcomes.It is crucial to tackle these challenges by advancing targeted therapeutic approaches in ongoing research endeavors.Variant RET fusions have been reported in several solid tumors,but are rarely reported in SCLC.CASE SUMMARY We present the first case of a KIF5B-RET fusion in a 65-year-old male patient with SCLC.To date,the patient has received the 4th line chemotherapy with anlotinib for one year and has shown a sustained favorable partial response.According to the results of next generation sequencing,this SCLC patient harbors the KIF5BRET fusion,suggesting that RET fusion could serve as a promising molecular target for SCLC treatment.Next-generation sequencing(NGS)plays a critical rolein comprehensively assessing the genotype and phenotype of cancer.CONCLUSION NGS can provide SCLC patients with personalized and targeted therapy options,thereby improving their likelihood of survival.展开更多
Small cell lung carcinoma(SCLC)is an aggressive malignancy known for its propensity for early and extensive metastatic spread.Gastric metastasis,where cancer cells disseminate from the lung to the stomach,is a rare bu...Small cell lung carcinoma(SCLC)is an aggressive malignancy known for its propensity for early and extensive metastatic spread.Gastric metastasis,where cancer cells disseminate from the lung to the stomach,is a rare but increasingly recognized complication of SCLC.This review provides a comprehensive overview of gastric metastasis in SCLC,addressing its clinical significance,diagnostic challenges,management strategies,and prognosis.Additionally,it examines the broader metastatic patterns of SCLC and compares them with other malignancies known for gastric metastasis.Gastric metastasis in SCLC,though infrequent,is clinically significant and often indicates advanced disease with a poor prognosis.SCLC typically metastasizes to the liver,brain,bones,and adrenal glands,with the stomach being an unusual site.The incidence of gastric meta-stasis ranges from 1%to 5%in autopsy studies,although this may be underes-timated due to diagnostic difficulties and asymptomatic early lesions.Diagnosing gastric metastasis presents several challenges,including the asymptomatic nature of many cases,limitations of conventional imaging techniques,and difficulties in distinguishing metastatic lesions from primary gastric cancer via endoscopy.Histopathological diagnosis requires careful examination to identify SCLC cells through their characteristic small cell morphology and neuroendocrine markers.Management of gastric metastasis in SCLC typically involves a multidisciplinary approach.Systemic therapy,pri-marily chemotherapy,remains the cornerstone of treatment,with palliative care addressing symptoms and complications.Surgical intervention is usually reserved for specific cases requiring symptomatic relief.The prognosis for patients with gastric metastasis from SCLC is generally poor,reflecting the advanced stage of the disease.Median survival is significantly re-duced compared to patients without gastric metastasis.This review emphasizes the need for enhanced awareness and early detection to improve patient outcomes and highlights the importance of ongoing research into better diagnostic and therapeutic strategies.展开更多
Background: Neuroendocrine neoplasms are those that develop from a neuroendocrine cell. They most commonly affect the lungs, gastrointestinal tract, and pancreas, being rare conditions in the female genital tract. Whe...Background: Neuroendocrine neoplasms are those that develop from a neuroendocrine cell. They most commonly affect the lungs, gastrointestinal tract, and pancreas, being rare conditions in the female genital tract. When present, these neoplasms often manifest with nonspecific signs and symptoms such as pain, itching, swelling, single-focus lesions, bleeding, and enlargement of inguinal lymph nodes, in addition to the presence of progressively enlarging vulvar nodules. Consequently, the diagnostic investigation involves histopathological examination and confirmation through immunohistochemistry. Objective: To present a comprehensive understanding of this rarely studied pathology. The primary objective is to provide valuable insights that could aid in the future development of universally applicable treatment guidelines. Case Presentation: A 57-year-old female, with no prior comorbidities, menopause at 36, who presented with a left vulvar nodule accompanied by intense pain and swelling, later diagnosed with small cell neuroendocrine carcinoma in the vulva. Conclusion: This case report highlights the importance of enhancing our knowledge regarding small cell neuroendocrine carcinoma in the vulva, given its scarcity in medical literature. The information presented here underscores the need for standardized diagnostic and treatment approaches, paving the way for future consensus on managing this uncommon but challenging neoplasm.展开更多
Small cell lung cancer (SCLC) is a poorly differentiated, highly malignant neuroendocrine tumor characterized by rapid growth, aggressiveness, and easy recurrence. It is usually found in late clinical stage and the op...Small cell lung cancer (SCLC) is a poorly differentiated, highly malignant neuroendocrine tumor characterized by rapid growth, aggressiveness, and easy recurrence. It is usually found in late clinical stage and the opportunity for surgery is lost. Therefore, surgery is often not used in clinical treatment. Although it is sensitive to chemoradiotherapy, it has a high recurrence rate and lacks effective treatment methods at present. Following chemotherapy and radiotherapy, immunotherapy for small cell lung cancer has become the mainstream research direction. Immunotherapy is profoundly changing the approach to cancer treatment due to its tolerable safety profile, sustained treatment response due to the production of immune memory, and effectiveness in a broad patient population. Immunotherapy for small cell lung cancer is one of the effective treatment methods for small cell lung cancer, and relevant studies are not rare, but there are still shortcomings such as intolerance of side effects and inaccurate evaluation of treatment timing. This article reviews the history of immunotherapy, the mechanism of action of immunodrugs, and the current immunodrugs used in the first-line treatment of extensive small cell lung cancer.展开更多
Small cell cancers were initially described in the lungs and later found to occur in a wide range of organs of the body, constituted a disease entity that is characterized by an aggrieve path/course and a huge disease...Small cell cancers were initially described in the lungs and later found to occur in a wide range of organs of the body, constituted a disease entity that is characterized by an aggrieve path/course and a huge disease related mortality. They are also called neuroendocrine tumors with peculiar histologic and biologic disease entity. Here we present two cases of small cell cancer of the prostate seen and managed in our facility with focus on their presentation, disease progression and outcome. The first patient was a 72-year-old retired military officer who presented with a progressively painful scrotal swelling of 3-month duration, and scrotal ulceration with contact bleeding of a month duration associated with a foul-smelling discharge. There was also history of progressive weight lost, loss of appetite and constipation. Patient was pale and lethargic on examination with a foul smelling exophytic scrotal mass. Serum PSA was 4 ng/l (within normal limit). Wedge biopsy and trucut prostate biopsy revealed small cell cancer of the prostate. Patient was resuscitated and prepared for chemoradiation, had a single dose of chemotherapy and died before the second dose. Second patient was a 63-year-old farmer who presented with lower urinary tract symptoms, progressive weight loss and constipation of two months duration, a known hypertensive and diabetic who has been regular on his medication. He was lethargic on examination, pale and unable to stand without support. Trucut prostate biopsy shows small cell cancer of the prostate. He was also resuscitated and being prepared for chemoradiation but died before commencement of treatment.展开更多
Objective This study aims to investigate the feasibility of knockdown of Survivin gene with small interfering RNA and to observe the apoptosis in gliomas which is influenced by siRNA. Methods Survivin specific siRNA o...Objective This study aims to investigate the feasibility of knockdown of Survivin gene with small interfering RNA and to observe the apoptosis in gliomas which is influenced by siRNA. Methods Survivin specific siRNA oligonucleotides were designed and synthesized artificially. This siRNA展开更多
文摘Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),are essential due to the limitations of simpler security measures,such as cryptography and firewalls.Due to their compact nature and low energy reserves,wireless networks present a significant challenge for security procedures.The features of small cells can cause threats to the network.Network Coding(NC)enabled small cells are vulnerable to various types of attacks.Avoiding attacks and performing secure“peer”to“peer”data transmission is a challenging task in small cells.Due to the low power and memory requirements of the proposed model,it is well suited to use with constrained small cells.An attacker cannot change the contents of data and generate a new Hashed Homomorphic Message Authentication Code(HHMAC)hash between transmissions since the HMAC function is generated using the shared secret.In this research,a chaotic sequence mapping based low overhead 1D Improved Logistic Map is used to secure“peer”to“peer”data transmission model using lightweight H-MAC(1D-LM-P2P-LHHMAC)is proposed with accurate intrusion detection.The proposed model is evaluated with the traditional models by considering various evaluation metrics like Vector Set Generation Accuracy Levels,Key Pair Generation Time Levels,Chaotic Map Accuracy Levels,Intrusion Detection Accuracy Levels,and the results represent that the proposed model performance in chaotic map accuracy level is 98%and intrusion detection is 98.2%.The proposed model is compared with the traditional models and the results represent that the proposed model secure data transmission levels are high.
基金ACKNOWLEDGEMENT First, thanks for the invitation from the organ- isers of IEEE/CIC ICCC 2013 held in Xi'an, China. This work was supported by the Na- tional Natural Science Foundation of China under Grants No. 60972047, No. 61231008 the National Science and Technology Major Project under Grams No. 2011ZX03005-004, No. 2011ZX03004-003, No. 2011ZX03005- 003-03, No. 2013ZX03004007-003+4 种基金 the Shannxi 13115 Project under Grant No. 2010ZDKG-26 the National Basic Research Program of China (973 Program) under Grant No. 2009CB320404 the Program for Changjiang Scholars and Inn- ovative Research Team in University under Gr- ant No. IRT0852 the 111 Project under Grant No. B08038 and the State Key Laboratory Fou- ndation under Grants No. ISN1002005, No. ISN090305.
文摘Small cells have been regarded as an appealing technique to boost resource reuse ratio. On the other hand, their large-scale and self-organised tendency would complicate the interference environment of mobile networks. Meanwhile, traffic class is booming in recent years, which leads to higher demand for net- work designers on Quality of Service (QoS) provision, and therefore users' diverse re- quirements may not be guaranteed in sucff'an interference limited scenario. To maximise the number of users with QoS demands as well as resource reuse ratio, we formulate the resource allocation problem into a multi-objective l0 norm form. It is shown to be NP hard, and an iterative method is employed to approach the optimal solution. Because of its limit of being not adaptive to large-scale networks, we also design a heuristic method based on chordal graph, which, however, could result in per- formance loss when the size of networks is small. Finally, by combining these two meth- ods, we devise a hybrid algorithm such that the allocation performs both efficiently and effectively. Simulation results illustrate the performance of our proposed methods in terms of outage probability and resource reuse ratio.
基金supported in part by National NSF of China under Grant No.61472445,No.61631020,No.61702525 and No.61702545in part by the NSF of Jiangsu Province under Grant No.BK20140076.5
文摘With the proliferation of small and mini drones, Drone Small Cells(DSCs) can cooperative multiple drones to provide communication service for ground users as emergency means or supplementary ones of traditional terrestrial cellular networks. In this paper, we study the fundamental problem of optimizing the deployment density of DSCs to achieve the maximum coverage performance. Most related works do not consider cumulative inter-cell interference when studying the coverage performance of DSCs. First, we derive an approximate and closed-form expression of the cumulative inter-cell interference which comes from both probabilistic Line-of-Sight(Lo S) and Non-Line-of-Sight(NLo S) links. Then, we analyze the coverage performance of DSCs and derive the transcendental function of optimal deployment density to obtain the maximum coverage. Last, we propose an algorithm to get the optimal deployment density with low complexity. We conduct both field experiments and Matlab simulations to verify the correctness of theoretical analysis. In addition, we show the impact of some factors on the relation between the deployment density and coverage performance through extensive numerical simulations.
基金partially supported by National Key Project of China under Grants No. 2013ZX03001007-004National Natural Science Foundation of China under Grants No. 61102052,61325012,61271219,91438115 and 61221001
文摘Switch policy is essential for small cells to properly serve variable number of users in an energy efficient way.However,frequently switching small cell base stations(SBSs) may increase the network operating cost,especially when there is an nonnegligible start-up energy cost.To this end,by observing the variety of user number,we focus on the design of a switch policy which minimize the cumulative energy consumption.A given user transmission rate is guaranteed and the capability of SBSs are limited as well.According to the knowledge on user number variety,we classify the energy consumption problem into two cases.In complete information case,to minimize the cumulative energy consumption,an offline solution is proposed according to critical segments.A heuristic algorithm for incomplete information case(HAIIC) is proposed by tracking the difference of cumulative energy consumption.The upper bound of the Energy Consumption Ratio(ECR) for HAIIC is derived as well.In addition,a practical Q-learning based probabilistic policy is proposed.Simulation results show that the proposed HAIIC algorithm is able to save energy efficiently.
文摘In order to handle the huge amounts of data transmitted through hot spots and to increase cell coverage in buildings, this paper proposes a sectored cellular network with small cells (SCNSC) embedded in each sector. Two region types, sectors and variable-radius small cells are classified in an SCNSC macro cell. Because the system capacity is enhanced by using fractional frequency reuse (FFR), the overall channel bandwidth is divided into two or three frequency bands depending on whether the number of sectors in a macro cell is even or odd. For the purpose of topological evaluation on the proposed SCNSC, we build an analytical model using Markov chain theory. The performance measures include new-call blocking and handoff-call dropping probabilities, average waiting times, and normalized throughputs in each sector and its embedded small cell by varying mobile stations’ moving speeds, the number of sectors, and the radius size of an embedded small cell. From the evaluation results, it is demonstrated that adjusting either the number of sectors or the coverage of an embedded cell can satisfy different service demands.
基金supported by the National High-tech Research and Development Program of China(863 Program)(2012AA111902)the Shanghai Natural Science Foundation(12ZR1433900)
文摘The shrinking of cell-size brings significant changes to the wireless uplink of densely small cells (DSCs). A codebook design is proposed that utilizes the strong line of sight (LOS) chan- nel component existing in a DSC system for uplink of the DSC system. To further improve the uplink performance, the high-rank codebook is designed based on singular value decomposition (SVD) due to the unnecessary preservation of strict constant modulus in the DSC system. And according to the simulation result, the proposed codebook leads to significant sum-rate gain and appreciable block error rate (BLER) performance improvement in the DSC system.
基金Supported by Science and Technology Plan Project of Jiaxing,No.2021AD30044Supporting Discipline of Neurology in Jiaxing,No.2023-ZC-006Affiliated Hospital of Jiaxing University,No.2020-QMX-16.
文摘BACKGROUND Small cell lung cancer(SCLC)is the most malignant type of lung cancer.Even in the latent period and early stage of the tumor,SCLC is prone to produce distant metastases with complex and diverse clinical manifestations.SCLC is most closely related to paraneoplastic syndrome,and some cases present as paraneoplastic peripheral neuropathy(PPN).PPN in SCLC appears early,lacks specificity,and often occurs before diagnosis of the primary tumor.It is easy to be misdiagnosed as a primary disease of the nervous system,leading to missed diagnosis and delayed diagnosis and treatment.CASE SUMMARY This paper reports two cases of SCLC with limb weakness as the first symptom.The first symptoms of one patient were rash,limb weakness,and abnormal electromyography.The patient was repeatedly referred to the hospital for limb weakness and rash for>1 year,during which time,treatment with hormones and immunosuppressants did not lead to significant improvement,and the condition gradually aggravated.The patient was later diagnosed with SCLC,and the dyskinesia did not worsen as the dermatomyositis improved after antineoplastic and hormone therapy.The second case presented with limb numbness and weakness as the first symptom,but the patient did not pay attention to it.Later,the patient was diagnosed with SCLC after facial edema caused by tumor thrombus invading the vein.However,he was diagnosed with extensive SCLC and died 1 year after diagnosis.CONCLUSION The two cases had PPN and abnormal electromyography,highlighting its correlation with early clinical indicators of SCLC.
文摘Neurodegeneration and traumatic brain injuries are leading causes of disability and present an enormous disease burden both in terms of patient suffering and healthcare cost.Treatment of brain lesions remains as a major challenge in medicine largely because of the limited regenerative capacity of the adult brain.
文摘BACKGROUND Small cell lung carcinoma(SCLC)is highly susceptible to metastasis in the early stages of the disease.However,the stomach is an uncommon site of metastasis in SCLC,and only a few cases of this type of metastasis have been reported.Therefore,SCLC gastric metastases have not been systematically characterized and are easily missed and misdiagnosed.CASE SUMMARY We report three cases of gastric metastasis from SCLC in this article.The first patient presented primarily with cough,hemoptysis,and epigastric fullness.The other two patients presented primarily with abdominal discomfort,epigastric distension,and pain.All patients underwent gastroscopy and imaging examinations.Meanwhile,the immunohistochemical results of the lesions in three patients were suggestive of small cell carcinoma.Finally,the three patients were diagnosed with gastric metastasis of SCLC through a comprehensive analysis.The three patients did not receive appropriate treatment and died within a short time.CONCLUSION Here,we focused on summarizing the characteristics of gastric metastasis of SCLC to enhance clinicians'understanding of this disease.
基金This project was supported by a grant from Natural Sci-ences Foundation of China(No.396 70 338)
文摘The effects of Shenmai injection (SMI) and am inophylline on apoptosis of sm all airway smooth muscle cells (SASMC) and the Fas/ Fas L expression in rats with papain- induced em physe- ma were investigated.Rat emphysema model was established by a single intratracheal instillation of papain.Apoptosis and Fas/Fas L expression of SASMC were detected by im munohistochemistry SABC and TU NEL assay at day1,3,5 ,7,15 ,30 after modeling,and the effect of SMI and am inophylline on them were observed.The results indicated that the Fas/Fas L expression positive rate in SASMC was2 .31± 0 .5 5 /1.2 8± 0 .4 7respectively.After a single intratracheal instillation of papain,the expression of Fas/Fas L positive rate in the placebo group was increased in a tim e- dependent manner.SMI could inhibit the expression of Fas/ Fas L ,but aminophylline couldn't. The positive rate of apoptosis in the control group was 0 .87± 0 .32 .After a single intratracheal in- stillation of papain,the SASMC apoptosis positive rate in the placebo group was increased in a tim e- dependent manner.The SASMC apoptosis rate in all groups was declined after treatment with SMI,but the effect of am inophylline was notobvious.Itwas dem onstrated thatin the patho- genesis of emphysem a Fas/Fas L played an important role in the regulation of SASMC apoptosis. SMI influenced the expression of Fas/ Fas L and declined SASMC apoptosis by inhibiting the releas- ing of inflamm atory m edia and played an im portant role in the therapy of em physema.
文摘It is generally accepted that adult bone marrow(BM) contains both hematopoietic stem cells(HSCs) and mesenchymal stem cells (MSCs). Recently, a rare population of stem cells different from HSCs and MSCs were identified in murine BM and human cord blood (CB), named as very small embryonic like(VSEL) stem cells. These cells are tiny round and CXCR4^+ Sca-1^+ Lin^- CD45^-, expressing SSEA-1/4, Oct-4 and Nanog, which have potent of differentiation into all three germ-layer lineages, such as cardiornyocytes, neural and pancreatic ceils.
文摘Small cell lung carcinoma metastatic to the stomach,whether synchronous or metachronous,is a rare phenomenon accounting for<0.5%of lung cancers.Hence it can be overlooked by clinicians resulting in delayed diagnosis.This manuscript comments on Yang et al’s article which reported 3 such cases.The main diagnostic features are based on routine morphology comprised of small cells with hyperchromatic nuclei,scant cytoplasm,brisk mitoses and necrosis.This can be supplemented by immunohistochemistry demonstrating positivity for cytokeratin,thyroid transcription factor-1 and neuroendocrine markers as well as a high Ki-67 labelling index.Imaging modalities such as positron emission tomography/contrast computed tomography help to confirm lung origin and rule out the possibility of extra-pulmonary small cell carcinoma.The predominant mechanism of spread is most likely hematogeneous.Prognosis is generally poor since this represents stage 4 disease but survival can be improved by chemo/ra-diotherapy and palliative surgery in select cases.Though outcomes have not changed much in the last several decades,the recent Food and Drug Adminis-tration approval of immune checkpoint inhibitors was a significant milestone as was the delineation of small cell lung carcinoma molecular subtypes.Liquid biopsies are increasingly being used for biomarker studies in clinical trials to assess treatment response and prognosis.
文摘Small cell lung cancer(SCLC)is a common type of primary lung cancer that contributes to approximately 15%of cases.It is closely associated with tobacco risk factors.It is also known as a type of lung cancer that has a high mortality rate within a short time due to its rapid growth rate(with tumor doubling time of 30 days)and its tendency to metastasize early in the disease process.The primary sites of metastasis in SCLC are similar to those in other primary lung cancers and often include the brain,bones,adrenal glands,liver,and lymph nodes.However,there are a few clinical reports of uncommon metastases,such as gastric metastasis from SCLC.Although the incidence of this clinical presentation is very low,reported cases have generally resulted in early mortality due to inadequate treatment.The purpose of this letter is to discuss the knowledge related to gastric metastasis from SCLC and remind clinical doctors not to miss atypical symptoms,thereby providing the right attitude to improve the prognosis for these patients.
基金Yu-Qing Xia Famous Old Chinese Medicine Heritage Workshop of“3+3”Project of Traditional Chinese Medicine Heritage in Beijing,Jing Zhong Yi Ke Zi(2021),No.73National Natural Science Foundation of China,No.81973640+1 种基金Nursery Program of Wangjing Hospital,Chinese Academy of Traditional Chinese Medicine,No.WJYY-YJKT-2022-05China Academy of Traditional Chinese Medicine Wangjing Hospital High-Level Chinese Medicine Hospital Construction Project Chinese Medicine Clinical Evidence-Based Research:The Evidence-Based Research of Electrothermal Acupuncture for Relieving Cancer-Related Fatigue in Patients With Malignant Tumor,No.WYYY-XZKT-2023-20.
文摘BACKGROUND Small cell lung cancer(SCLC)is a common and aggressive subtype of lung cancer.It is characterized by rapid growth and a high mortality rate.Approximately 10%of patients with SCLC present with brain metastases at the time of diagnosis,which is associated with a median survival of 5 mo.This study aimed to summarize the effect of bevacizumab on the progression-free survival(PFS)and overall survival of patients with brain metastasis of SCLC.CASE SUMMARY A 62-year-old man was referred to our hospital in February 2023 because of dizziness and numbness of the right lower extremity without headache or fever for more than four weeks.The patient was diagnosed with limited-stage SCLC.He received 8 cycles of chemotherapy combined with maintenance bevacizumab therapy and achieved a PFS of over 7 mo.CONCLUSION The combination of bevacizumab and irinotecan effectively alleviated brain metastasis in SCLC and prolonged PFS.
基金Meat Processing Key Laboratory of Sichuan Province,No.22-R-16.
文摘BACKGROUND Small cell lung cancer(SCLC)exhibits a pronounced tendency for metastasis and relapse,and the acquisition of resistance to chemotherapy and radiotherapy,leading to complexity in treatment outcomes.It is crucial to tackle these challenges by advancing targeted therapeutic approaches in ongoing research endeavors.Variant RET fusions have been reported in several solid tumors,but are rarely reported in SCLC.CASE SUMMARY We present the first case of a KIF5B-RET fusion in a 65-year-old male patient with SCLC.To date,the patient has received the 4th line chemotherapy with anlotinib for one year and has shown a sustained favorable partial response.According to the results of next generation sequencing,this SCLC patient harbors the KIF5BRET fusion,suggesting that RET fusion could serve as a promising molecular target for SCLC treatment.Next-generation sequencing(NGS)plays a critical rolein comprehensively assessing the genotype and phenotype of cancer.CONCLUSION NGS can provide SCLC patients with personalized and targeted therapy options,thereby improving their likelihood of survival.
文摘Small cell lung carcinoma(SCLC)is an aggressive malignancy known for its propensity for early and extensive metastatic spread.Gastric metastasis,where cancer cells disseminate from the lung to the stomach,is a rare but increasingly recognized complication of SCLC.This review provides a comprehensive overview of gastric metastasis in SCLC,addressing its clinical significance,diagnostic challenges,management strategies,and prognosis.Additionally,it examines the broader metastatic patterns of SCLC and compares them with other malignancies known for gastric metastasis.Gastric metastasis in SCLC,though infrequent,is clinically significant and often indicates advanced disease with a poor prognosis.SCLC typically metastasizes to the liver,brain,bones,and adrenal glands,with the stomach being an unusual site.The incidence of gastric meta-stasis ranges from 1%to 5%in autopsy studies,although this may be underes-timated due to diagnostic difficulties and asymptomatic early lesions.Diagnosing gastric metastasis presents several challenges,including the asymptomatic nature of many cases,limitations of conventional imaging techniques,and difficulties in distinguishing metastatic lesions from primary gastric cancer via endoscopy.Histopathological diagnosis requires careful examination to identify SCLC cells through their characteristic small cell morphology and neuroendocrine markers.Management of gastric metastasis in SCLC typically involves a multidisciplinary approach.Systemic therapy,pri-marily chemotherapy,remains the cornerstone of treatment,with palliative care addressing symptoms and complications.Surgical intervention is usually reserved for specific cases requiring symptomatic relief.The prognosis for patients with gastric metastasis from SCLC is generally poor,reflecting the advanced stage of the disease.Median survival is significantly re-duced compared to patients without gastric metastasis.This review emphasizes the need for enhanced awareness and early detection to improve patient outcomes and highlights the importance of ongoing research into better diagnostic and therapeutic strategies.
文摘Background: Neuroendocrine neoplasms are those that develop from a neuroendocrine cell. They most commonly affect the lungs, gastrointestinal tract, and pancreas, being rare conditions in the female genital tract. When present, these neoplasms often manifest with nonspecific signs and symptoms such as pain, itching, swelling, single-focus lesions, bleeding, and enlargement of inguinal lymph nodes, in addition to the presence of progressively enlarging vulvar nodules. Consequently, the diagnostic investigation involves histopathological examination and confirmation through immunohistochemistry. Objective: To present a comprehensive understanding of this rarely studied pathology. The primary objective is to provide valuable insights that could aid in the future development of universally applicable treatment guidelines. Case Presentation: A 57-year-old female, with no prior comorbidities, menopause at 36, who presented with a left vulvar nodule accompanied by intense pain and swelling, later diagnosed with small cell neuroendocrine carcinoma in the vulva. Conclusion: This case report highlights the importance of enhancing our knowledge regarding small cell neuroendocrine carcinoma in the vulva, given its scarcity in medical literature. The information presented here underscores the need for standardized diagnostic and treatment approaches, paving the way for future consensus on managing this uncommon but challenging neoplasm.
文摘Small cell lung cancer (SCLC) is a poorly differentiated, highly malignant neuroendocrine tumor characterized by rapid growth, aggressiveness, and easy recurrence. It is usually found in late clinical stage and the opportunity for surgery is lost. Therefore, surgery is often not used in clinical treatment. Although it is sensitive to chemoradiotherapy, it has a high recurrence rate and lacks effective treatment methods at present. Following chemotherapy and radiotherapy, immunotherapy for small cell lung cancer has become the mainstream research direction. Immunotherapy is profoundly changing the approach to cancer treatment due to its tolerable safety profile, sustained treatment response due to the production of immune memory, and effectiveness in a broad patient population. Immunotherapy for small cell lung cancer is one of the effective treatment methods for small cell lung cancer, and relevant studies are not rare, but there are still shortcomings such as intolerance of side effects and inaccurate evaluation of treatment timing. This article reviews the history of immunotherapy, the mechanism of action of immunodrugs, and the current immunodrugs used in the first-line treatment of extensive small cell lung cancer.
文摘Small cell cancers were initially described in the lungs and later found to occur in a wide range of organs of the body, constituted a disease entity that is characterized by an aggrieve path/course and a huge disease related mortality. They are also called neuroendocrine tumors with peculiar histologic and biologic disease entity. Here we present two cases of small cell cancer of the prostate seen and managed in our facility with focus on their presentation, disease progression and outcome. The first patient was a 72-year-old retired military officer who presented with a progressively painful scrotal swelling of 3-month duration, and scrotal ulceration with contact bleeding of a month duration associated with a foul-smelling discharge. There was also history of progressive weight lost, loss of appetite and constipation. Patient was pale and lethargic on examination with a foul smelling exophytic scrotal mass. Serum PSA was 4 ng/l (within normal limit). Wedge biopsy and trucut prostate biopsy revealed small cell cancer of the prostate. Patient was resuscitated and prepared for chemoradiation, had a single dose of chemotherapy and died before the second dose. Second patient was a 63-year-old farmer who presented with lower urinary tract symptoms, progressive weight loss and constipation of two months duration, a known hypertensive and diabetic who has been regular on his medication. He was lethargic on examination, pale and unable to stand without support. Trucut prostate biopsy shows small cell cancer of the prostate. He was also resuscitated and being prepared for chemoradiation but died before commencement of treatment.
文摘Objective This study aims to investigate the feasibility of knockdown of Survivin gene with small interfering RNA and to observe the apoptosis in gliomas which is influenced by siRNA. Methods Survivin specific siRNA oligonucleotides were designed and synthesized artificially. This siRNA