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ISSR Analysis of Hybrid Descendants of Roses 被引量:1
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作者 Che Dai-di Su Cheng-yuan +4 位作者 Zhang Jin-zhu Chen Xue Ma Xue Wang Na Li Wen-tian 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第1期1-4,共4页
Four different rose hybrid populations were analyzed by ISSR technique with nine polymorphic primers. All of the primers produced 64 bands, of which 59 were polymorphic. The average of polymorphic bands was 6.6 for ea... Four different rose hybrid populations were analyzed by ISSR technique with nine polymorphic primers. All of the primers produced 64 bands, of which 59 were polymorphic. The average of polymorphic bands was 6.6 for each primer. The percentage of polymorphism ranged from 57.1% to 100%, with an average of 92.3%. An UPGMA dendrogram showed five groups. The primer numbered with PI9 and PI11 had relatively high resolution in identifying the F1 offspring in this research. 展开更多
关键词 ROSE hybrid descendants ISSR genetic diversity
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Pursuing Sustainable Development for our Descendants
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《China Today》 1997年第8期7-7,共1页
关键词 Pursuing Sustainable Development for our descendants
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Roles of Upper-Level Descending Inflow in Moat Development in Simulated Tropical Cyclones with Secondary Eyewall Formation
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作者 Nannan QIN Liguang WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1100-1114,共15页
This study investigated the effects of upper-level descending inflow(ULDI)associated with inner-eyewall convection on the formation of the moat in tropical cyclones(TCs)with secondary eyewall formation(SEF).In our num... This study investigated the effects of upper-level descending inflow(ULDI)associated with inner-eyewall convection on the formation of the moat in tropical cyclones(TCs)with secondary eyewall formation(SEF).In our numerical experiments,a clear moat with SEF occurred in TCs with a significant ULDI,while no SEF occurred in TCs without a significant ULDI.The eyewall convection developed more vigorously in the control run.A ULDI occurred outside the inner-eyewall convection,where it was symmetrically unstable.The ULDI was initially triggered by the diabatic warming released by the inner eyewall and later enhanced by the cooling below the anvil cloud.The ULDI penetrated the outer edge of the inner eyewall with relatively dry air and prevented excessive solid-phase hydrometeors from being advected further outward.It produced extensive sublimation cooling of falling hydrometeors between the eyewall and the outer convection.The sublimation cooling resulted in negative buoyancy and further induced strong subsidence between the eyewall and the outer convection.As a result,a clear moat was generated.Development of the moat in the ongoing SEF prevented the outer rainband from moving farther inward,helping the outer rainband to symmetrize into an outer eyewall.In the sensitivity experiment,no significant ULDI formed since the eyewall convection was weaker,and the eyewall anvil developed relatively lower,meaning the formation of a moat and thus an outer eyewall was less likely.This study suggests that a better-represented simulation of inner-eyewall convective structures and distribution of the solid-phase hydrometeors is important to the prediction of SEF. 展开更多
关键词 tropical cyclone secondary eyewall formation upper-level descending inflow eyewall convection
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Carotid versus axillary artery cannulation for descending aorta remodeling in type A acute aortic dissection
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作者 Qin Jiang Tao Yu +3 位作者 Ke-Li Huang Ke Liu Xi Li Sheng-Shou Hu 《World Journal of Cardiology》 2024年第10期564-573,共10页
BACKGROUND Arterial cannulation sites for the surgical repair of type A aortic dissection(AAD)have evolved from right axillary artery(AA)cannulation to bilateral carotid artery(CA)based of femoral artery(FA)cannulatio... BACKGROUND Arterial cannulation sites for the surgical repair of type A aortic dissection(AAD)have evolved from right axillary artery(AA)cannulation to bilateral carotid artery(CA)based of femoral artery(FA)cannulation.Postoperative descending aorta remodeling is closely linked to the false lumen area ratio(FLAR),defined as false lumen area/aortic area,as well as to the incidence of renal replacement therapy(RRT).AIM To investigate the effect of the updated arterial cannulation strategy on descending aortic remodeling.METHODS A total of 443 AAD patients who received FA combined cannulation between March 2015 and March 2023 were included in the study.Of these,209 received right AA cannulation and 234 received bilateral CA cannulation.The primary outcome was the change in FLAR,as calculated from computed tomography angiography in three segments of the descending aorta:Thoracic(S1),upper abdominal(S2),and lower abdominal(S3).Secondary outcomes were the incidence of RRT and the serum inflammation response,as observed by the levels of high sensitivity C reaction protein(hs-CRP)and Interleukin-6(IL-6).RESULTS The postoperative/preoperative ratio of FLAR in S2 and S3 was higher in the AA group compared to the CA group(S2:0.80±0.08 vs 0.75±0.07,P<0.001;S3:0.57±0.12 vs 0.50±0.12,P<0.001,respectively).The AA group also had a significantly higher incidence of RRT(19.1%vs 8.5%,P=0.001;odds ratio:2.533,95%CI:1.427-4.493)and higher levels of inflammation cytokines 24 h after the procedure[hr-CRP:117±17 vs 104±15 mg/L;IL-6:129(103,166)vs 83(69,101)pg/mL;both P<0.001]compared to the CA group.CONCLUSION The CA cannulation strategy was associated with better abdominal aorta remodeling after AAD repair compared to AA cannulation,as observed by a greater change in FLAR and lower incidence of RRT. 展开更多
关键词 Acute type A aortic dissection Bilateral carotid arterial cannulation Descending aortic remodeling False lumen area ratio PROGNOSIS
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Lateral circumflex femoral artery perforator flap for the reconstruction of head soft tissue defects:Cross-region venous anastomosis
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作者 Gongxue Zhang Wenhu Jin +3 位作者 Ziyang Zhang Lei Shi Rui Yang Dali Wang 《Chinese Journal of Plastic and Reconstructive Surgery》 2024年第3期111-115,共5页
Background:Owing to its unique characteristics,the lateral circumflex femoral artery perforator(LCFAP)flap is often preferred for repairing head wounds with exposed skulls.However,given the vascular distribution in th... Background:Owing to its unique characteristics,the lateral circumflex femoral artery perforator(LCFAP)flap is often preferred for repairing head wounds with exposed skulls.However,given the vascular distribution in the head,particularly the veins,can lead to postoperative complications such as venous congestion of the flap.The rates of vascular exploration and necrosis in these flaps are significantly higher than in other body regions.Therefore,it is crucial to identify a safe and effective method for venous anastomosis of free flaps in the head region.Methods:This retrospective case series study included 10 patients with large head soft tissue defects treated at the Burn and Plastic Surgery Department of the Affiliated Hospital of Zunyi Medical University from January 2020 to December 2022.The head defects were reconstructed using LCFAP flaps,with flap veins anastomosed to the external jugular vein in the neck,either directly or via a bridging technique.Results:Among the 10 adult patients with massive head wound defects,7(70%)were men.The patients’mean age was 53.0 years(48–59 years).The wound defects were caused by trauma in 6(60%)patients and by tumors in 4(40%)patients.Postoperatively,no significant complications occurred,and all LCFAP flap survived without necrosis.Conclusion:The descending branch of the LCFAP flap effectively repairs massive head wound defects.The venous anastomosis method for this flap is associated with a low incidence of venous complications and a high patency rate,making it a clinically valuable reference. 展开更多
关键词 Descending branch of lateral External jugular vein Wound repair Perforator flap
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Therapeutic efficacy of methylprednisolone sodium succinate via diverse administration routes for mid-to high-frequency sudden sensorineural hearing loss
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作者 Xiang-Da Meng Ting-Ting Li Li-Min Deng 《World Journal of Clinical Cases》 SCIE 2024年第18期3321-3331,共11页
BACKGROUND Sudden sensorineural hearing loss(SSNHL),characterized by a rapid and unexplained loss of hearing,particularly at moderate to high frequencies,presents a significant clinical challenge.The therapeutic use o... BACKGROUND Sudden sensorineural hearing loss(SSNHL),characterized by a rapid and unexplained loss of hearing,particularly at moderate to high frequencies,presents a significant clinical challenge.The therapeutic use of methylprednisolone sodium succinate(MPSS)via different administration routes,in combination with conventional medications,remains a topic of interest.AIM To compare the therapeutic efficacy of MPSS administered via different routes in combination with conventional drugs for the treatment of mid-to high-frequency SSNHL.METHODS The medical records of 109 patients with mid-to high-frequency SSNHL were analyzed.The patients were divided into three groups based on the route of administration:Group A[intratympanic(IT)injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection],Group B(intravenous injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection),and Group C(single IT injection of MPSS).The intervention effects were compared and analyzed.RESULTS The posttreatment auditory thresholds in Group A(21.23±3.34)were significantly lower than those in Groups B(28.52±3.36)and C(30.23±4.21;P<0.05).Group A also exhibited a significantly greater speech recognition rate(92.23±5.34)than Groups B and C.The disappearance time of tinnitus,time to hearing recovery,and disappearance time of vertigo in Group A were significantly shorter than those in Groups B and C(P<0.05).The total effective rate in Group A(97.56%)was significantly greater than that in Groups B and C(77.14%and 78.79%,χ^(2)=7.898,P=0.019).Moreover,the incidence of adverse reactions in Groups A and C was significantly lower than that in Group B(4.88%,3.03%vs 2.57%,χ^(2)=11.443,P=0.003),and the recurrence rate in Group A was significantly lower than that in Groups B and C(2.44%vs 20.00%vs 21.21%,χ^(2)=7.120,P=0.028).CONCLUSION IT injection of MPSS combined with conventional treatment demonstrates superior efficacy and safety compared to systemic administration via intravenous infusion and a single IT injection of MPSS.This approach effectively improves patients'hearing and reduces the risk of disease recurrence. 展开更多
关键词 Sudden loss of hearing at middle-and high-frequency of the descending type Methylprednisolone sodium succinate Intratympanic injection Intravenous injection
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Extensively infarcted giant solitary hamartomatous polyp treated with endoscopic full-thickness resection:A case report
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作者 Lu Ye Ji-Hong Zhong +4 位作者 Yong-Pan Liu Dan-Dan Chen Si-Yi Ni Fa-Quan Peng Shuo Zhang 《World Journal of Clinical Cases》 SCIE 2023年第8期1782-1787,共6页
BACKGROUND Solitary hamartomatous polyps(SHPs)are rare lesions.Endoscopic full-thickness resection(EFTR)is a highly efficient and minimally invasive endoscopic procedure that benefits from complete lesion removal and ... BACKGROUND Solitary hamartomatous polyps(SHPs)are rare lesions.Endoscopic full-thickness resection(EFTR)is a highly efficient and minimally invasive endoscopic procedure that benefits from complete lesion removal and high safety.CASE SUMMARY A 47-year-old man was admitted to our hospital after experiencing hypogastric pain and constipation for over fifteen days.Computed tomography and endoscopy revealed a giant pedunculated polyp(approximately 18 cm long)in the descending and sigmoid colon.This is the largest SHP reported to date.Having considered the condition of the patient and mass growth,the polyp was removed using EFTR.CONCLUSION On the basis of clinical and pathological evaluations,the mass was considered an SHP. 展开更多
关键词 Solitary hamartomatous polyp Endoscopic full-thickness resection DIAGNOSIS TREATMENT Descending colon Case report
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Variant of Wellen’s syndrome in type 1 diabetic patient: A case report
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作者 Mukosolu Florence Obi Manjari Sharma +4 位作者 Vikhyath Namireddy Paul Gargiulo Chelsea Noel Cho Hyun Blossom De Gale 《World Journal of Cardiology》 2023年第9期462-468,共7页
BACKGROUND Wellen’s syndrome is a form of acute coronary syndrome associated with proximal left anterior descending artery(LAD)stenosis and characteristic electro-cardiograph(ECG)patterns in pain free state.The abnor... BACKGROUND Wellen’s syndrome is a form of acute coronary syndrome associated with proximal left anterior descending artery(LAD)stenosis and characteristic electro-cardiograph(ECG)patterns in pain free state.The abnormal ECG pattern is classified into type A(biphasic T waves)and type B(deeply inverted T waves),based on the T wave pattern seen in the pericodial chest leads.CASE SUMMARY We present the case of a 37-year-old male with history of type 1 diabetes mellitus(T1DM),gastroparesis,mild peripheral artery disease and right toe cellulitis on IV antibiotics who presented to the emergency department with nausea,vomiting and abdominal pain for 3 d and as a result couldn’t take his insulin.Noted to have fasting blood sugar 392 mg/dL.Admitted for diabetic gastroparesis.During the hospital course,the patient was asymptomatic and denied any chest pain.On admission,No ECG and troponin draws were performed.On day 2,the patient became hypoxic with oxygen saturation 80%on room air,intermittent mild right-sided chest pain which he attributed to vomiting from his gastroparesis.Initial ECG done was significant for Biphasic T wave changes in leads V2 and V3 and elevated high sensitivity troponin.Patient was transitioned to cardiac intensive care unit and cardiac catheterization performed with result significant for extensive coronary artery disease.CONCLUSION This case highlights an exceptional manifestation of Wellen's syndrome,wherein the right coronary artery and circumflex artery display a remarkable 100%constriction,alongside a proximal LAD stenosis of 90%-95%.Notably,this occurrence transpired in a patient grappling with extensive complications arising from T1DM.Moreover,it underscores the utmost significance of promptly recognizing the presence of Wellen's syndrome and swiftly initiating appropriate medical intervention. 展开更多
关键词 Wellens’s syndrome Biphasic T waves Deeply inverted T waves Precordial leads Left anterior descending artery Pseudo-normalization Right coronary artery Left circumflex artery Case report
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Existence and Concentration of Sign-Changing Solutions of Quasilinear Choquard Equation
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作者 Die Wang Yuqi Wang Shaoxiong Chen 《Journal of Applied Mathematics and Physics》 2023年第4期1124-1151,共28页
In this paper, we study the following quasilinear equation of choquard type: where A(x,t) is given real functions on R<sup>N</sup> × R and with N ≥ 3, 1 p N, max{N-2p,1} α N, , and ε > 0 is a sm... In this paper, we study the following quasilinear equation of choquard type: where A(x,t) is given real functions on R<sup>N</sup> × R and with N ≥ 3, 1 p N, max{N-2p,1} α N, , and ε > 0 is a small parameter, I<sub>α</sub> is the Riesz potential. We establish for small ε the existence of a sequence of sign-changing solutions concentrating near a given local minimum point of the bounded potential function V by using the method of invariant sets of descending flow, perturbation method and truncation technique. . 展开更多
关键词 Quasilinear Choquard Equation The Method of Invariant Sets of Descending Flow TRUNCATION Sign-Changing Solutions
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赵学敏亲族考
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作者 李健 张卫 +1 位作者 梁飞 张瑞贤 《中药与临床》 2015年第2期101-103,共3页
本文对清代药学家赵学敏的亲属进行了文献调查,对其父亲、兄弟、儿子、外甥、岳父、内兄、表戚、门人、仆人等进行了梳理,以冀对今后研究赵学敏及其著作《本草纲目拾遗》、《串雅内外编》等有所帮助。
关键词 ZHAO Xuemin RELATIVES descendants VERIFICATION
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Prophylactic captopril reduces perioperative myocardial ischemia in dogs
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作者 王士雯 陈鸣和 谭端军 《中国介入心脏病学杂志》 1998年第4期194-194,共1页
Perioperative myocardial ischemia(PMI) is mainly caused by increasesin sympathetic nervous system activity due to stress,which results incoronary endothelial dysfunction,hence that it is hypothesized thatcaptopril may... Perioperative myocardial ischemia(PMI) is mainly caused by increasesin sympathetic nervous system activity due to stress,which results incoronary endothelial dysfunction,hence that it is hypothesized thatcaptopril may improve PMI.In our study,twenty mongrel dogs wererandomized for four groups;group Ⅰ:control,group Ⅱ:myocardialinfarction (MI) model,Group Ⅲ:MI+partial gastrectomy,group Ⅳ:MI+captopril+partial gastrectomy.Myocardial infarction wasproduced by ligation of left anterior descending coronary artery exceptthe group Ⅰ.In the group Ⅲ and Ⅳ,the hemodynamics,plasmaendothelin (ET) and nitric oxide (NO) on baseline,pre-andpostoperation were investigated two weeks after MI All animals werekilled by overdose anesthetic and their cardiac samples of non-infarction area taken for examining nitric oxide synthase (NOS)mRNA expression levels in vascular endothelial cells.Results:ingroup Ⅲ,the operation decreased the maximal rate of left ventricularpressure rise (LV+dP/dtmax),cardiac index (CI) and plasma No level,and increased left ventricular end diastolic pressure (LVEDP),time-course of isovolumic pressure fall (T constant),total peripheralresistance (TPR) and the levels of ET.In group Ⅳ,40 minutes afteradminstration of captopril,the TPR was decresed,and the t constantwas incresed significantly.The operation attenuated the TPR and Tconstant,but didn’t affect the other values.In situ hybridization it wasshowed that the expression levels of NOS mRNA was the highest ingroup Ⅰ,lower in groups Ⅱ and Ⅳ,and the lowest in group Ⅲ.Conclusions:1.Partial gastrectomy performed after myocardialinfarction may induce left ventricular systolic and diastolic dysfunction,and may produce coronary endothelial dysfunction;2.captopril canimprove left ventricular dysfuction and endothelial dysfunctioninduced by noncardiac operation. 展开更多
关键词 gastrectomy DESCENDING SYMPATHETIC DIASTOLIC LVEDP minutes baseline systolic examining attenuated
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The Alienation and Loneliness in Orpheus Descending
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作者 陈瑶琼 《海外英语》 2016年第23期164-165,共2页
Orpheus Descending is written by American famous playwright Tennessee Williams. According to the portrayal of a series marginalized people, this drama presents the solitude in human beings' heart and the estrangem... Orpheus Descending is written by American famous playwright Tennessee Williams. According to the portrayal of a series marginalized people, this drama presents the solitude in human beings' heart and the estrangement in interpersonal relations. This paper tries to analyze the solitude theme in this drama from philosophic aspect and realistic aspect, combining alienation theory and existentialism theory to analyze the reason and the manifestation of solitude. 展开更多
关键词 ALIENATION LONELINESS Orpheus Descending
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The hypothalamic-spinal dopaminergic system:a target for pain modulation 被引量:10
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作者 Michelino Puopolo 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第6期925-930,共6页
Nociceptive signals conveyed to the dorsal horn of the spinal cord by primary nociceptors are subject to extensive modulation by local neurons and by supraspinal descending pathways to the spinal cord before being rel... Nociceptive signals conveyed to the dorsal horn of the spinal cord by primary nociceptors are subject to extensive modulation by local neurons and by supraspinal descending pathways to the spinal cord before being relayed to higher brain centers. Descending modulatory pathways to the spinal cord comprise,among others, noradrenergic, serotonergic, γ-aminobutyric acid(GABA)ergic, and dopaminergic fibers.The contributions of noradrenaline, serotonin, and GABA to pain modulation have been extensively investigated. In contrast, the contributions of dopamine to pain modulation remain poorly understood.The focus of this review is to summarize the current knowledge of the contributions of dopamine to pain modulation. Hypothalamic A11 dopaminergic neurons project to all levels of the spinal cord and provide the main source of spinal dopamine. Dopamine receptors are expressed in primary nociceptors as well as in spinal neurons located in different laminae in the dorsal horn of the spinal cord, suggesting that dopamine can modulate pain signals by acting at both presynaptic and postsynaptic targets. Here, I will review the literature on the effects of dopamine and dopamine receptor agonists/antagonists on the excitability of primary nociceptors, the effects of dopamine on the synaptic transmission between primary nociceptors and dorsal horn neurons, and the effects of dopamine on pain in rodents. Published data support both anti-nociceptive effects of dopamine mediated by D2-like receptors and pro-nociceptive effects mediated by D1-like receptors. 展开更多
关键词 A11 nucleus DESCENDING modulation dopamine DORSAL horn DORSAL root GANGLIA D2 RECEPTORS D1 RECEPTORS NOCICEPTORS pain SPINAL cord
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Gustiness and Coherent Structure of Strong Winds and Their Role in Dust Emission and Entrainment 被引量:7
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作者 曾庆存 程雪玲 +1 位作者 胡非 彭珍 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第1期1-13,共13页
After the passage of a cold front, spring in northern China, the outbreak of strong wind is often accompanied by dust emissions. Through analyses of data in the atmospheric boundary layer during a typical case, it is ... After the passage of a cold front, spring in northern China, the outbreak of strong wind is often accompanied by dust emissions. Through analyses of data in the atmospheric boundary layer during a typical case, it is revealed there are rather regular gust wave packets superimposed on the basic strong wind flow. The gust-wind wave packets have a period equal to around 3 6 rains and possess coherent structure. As the vertical transport of momentum is decomposed into separate parts by (a) basic flow, (b) gust-wind, and (c) turbulence, they are all in a downwards direction at the lower levels of the atmospheric boundary layer during strong wind periods. However, (a) is the largest, while (b) and (c) are comparable. All these are very different from the case of normal weather. Besides, the friction velocity at the ground surface is also much larger than that of normal weather and should be corrected by taking the contributions of the basic flow and gust-wind into account.The strong basic flow with descending motion is very favorable for soil erosion and sand/dust emissions, but suppresses the entrainment of dust particles by keeping them within the bottom levels of the atmospheric boundary layer. Owing to the coherent structure of gust-wind, dust particles can effectively overcome the systematic descending air motion and penetrate into the middle and upper levels of the atmospheric boundary layer, and then propagate further and diffuse into the troposphere where ascending air motion prevails. 展开更多
关键词 gust-wind coherent structure descending motion dust storm soil erosion dust entrainment
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Coronary collateral circulation: Effects on outcomes of acute anterior myocardial infarction after primary percutaneous coronary intervention 被引量:7
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作者 Bin Wang Ya-Ling Han Yi Li Quan-Min Jing Shou-Li Wang Ying-Yan Ma Geng Wang Bo Luan Xiao-Zeng Wang 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2011年第2期93-98,共6页
Background To investigate the effects of collateral coronary circulation on the outcome of the patients with anterior myocardial infarction (MI) with left anterior desending artery occlusion abruptly. Methods Data o... Background To investigate the effects of collateral coronary circulation on the outcome of the patients with anterior myocardial infarction (MI) with left anterior desending artery occlusion abruptly. Methods Data of 189 patients with acute anterior MI who had a primary percutaneous coronary intervention (PCI) in the first 12 h from the onset of symptoms between January 2004 and December 2008 were retrospective analyzed. Left anterior descending arteries (LAD) of all patients were occluded. LADs were reopened with primary PCI. According to the collateral circulation, all patients were classified to two groups: no collateral group (n = 111), patients without angiographic collateral filling of LAD or side branches (collateral index 0) and collateral group (n = 78), and patients with angiographic collateral filling of LAD or side branches (collateral index 1, 2 or 3). At one year' s follow-up, the occurrence of death, reinfarctlon, stent thrombosis (ST), target vessel revascularization and readmission because of heart failure were observed. Results At one year, the mortality was lower in patients with collateral circulation compared with those without collateral circulation (1% vs. 8%, P = 0.049), whereas there Were no differences in the occurrence of reinfarction, ST, target vessel revascularization and readmission because of heart failure. The occurrence of composite of endpoint was lower in patients with collateral circulation compared with those without collateral circulation (12% vs. 26%; P = 0.014). Conclusions Pre-exist collateral circulation may prefigure the satisfactory prognosis to the patients with acute anterior MI after primary PCI in the first 12 h of MI onset. 展开更多
关键词 collateral circulation myocardial infarction MORTALITY left anterior descending artery
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Shift control method for the local time at descendi ngnode based on sun-synchronous orbit satellite 被引量:5
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作者 Yang Yong'an Feng Zuren +1 位作者 Sun Linyan Tan Wei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第1期141-145,共5页
This article analyzes the shift factors of the descending node local time for sun-synchronous satellites and proposes a shift control method to keep the local time shift within an allowance range. It is found that the... This article analyzes the shift factors of the descending node local time for sun-synchronous satellites and proposes a shift control method to keep the local time shift within an allowance range. It is found that the satellite orbit design and the orbit injection deviation are the causes for the initial shift velocity, whereas the atmospheric drag and the sun gravitational perturbation produce the shift acceleration. To deal with these shift factors, a shift control method is put forward, through such methods as orbit variation design, orbit altitude, and inclination keeping control. The simulation experiment and practical application have proved the effectiveness of this control method. 展开更多
关键词 space engineering sun-synchronous orbit satellite local time of descending node drift control method.
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Negative pressure catheter drainage and jejunal feeding for descending necrotizing mediastinitis by interventional techniques:a retrospective study 被引量:6
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作者 Gang Wu Meipan Yin +6 位作者 Yi Fang Gang Liu Yonggang Luo Weihong Xie Yaozhang Dai Jin Shi Xinwei Han 《Journal of Interventional Medicine》 2018年第2期106-111,共6页
Purpose: Descending necrotizing mediastinitis(DNM) is a lethal and acute suppurative disease. This report aimed to summarize our experience in the treatment of DNM with continuous negative pressure catheter drainage a... Purpose: Descending necrotizing mediastinitis(DNM) is a lethal and acute suppurative disease. This report aimed to summarize our experience in the treatment of DNM with continuous negative pressure catheter drainage and transnasal jejunal feeding by interventional techniques. Materials and Methods: We retrospectively analyzed relevant clinical data of patients with DNM who underwent continuous negative pressure catheter drainage and transnasal jejunal feeding. All drainage catheters and jejunal feeding tubes were inserte d by interventional techniques. Results: In total, 21 patients were diagnosed with DNM by esophagography and computed tomography(CT). Catheters for the drainage of mediastinal abscesses as well as transnasal jejunal feeding tubes were successfully placed in all patients, indicating a 100% success rate. Of all patients, 13 underwent insertion of abscess drainage catheters through percutaneous puncture under DynaCT guidance, while eight had drainage catheter insertion through fistula orifices in the posterior nasopharyngeal wall or esophagus under fluoroscopic guidance. In total, 26 drainage tubes were inserted. One patient with diabetes died of sepsis and diabetic ketoacidosis 5 days postoperatively, while the remaining 20 patients showed good recovery with successful removal of the drainage catheters. Durations of catheterization were 45.2±50.44 days. The overall clinical success rate was 95.2%. Conclusion: The above described methods are non-surgical, minimally invasive and efficacious, and may be alternative therapeutic tools for patients who are not eligible for surgical operation, have a high postoperative risk, or are more likely to choose minimally invasive techniques. 展开更多
关键词 DESCENDING NECROTIZING MEDIASTINITIS drainage INTERVENTIONAL RADIOLOGY Intensive care
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Laparoscopic right hemicolectomy for ascending colon cancer with persistent mesocolon 被引量:3
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作者 Atsushi Tsuruta Akimasa Kawai +4 位作者 Yasuo Oka Hideo Okumura Hideo Matsumoto Toshihiro Hirai Masafumi Nakamura 《World Journal of Gastroenterology》 SCIE CAS 2014年第18期5557-5560,共4页
Persistent ascending or descending mesocolon is an embryological anomaly that occurs during the final process of intestinal development in organogenesis.Specifically,the primitive dorsal mesocolon fails to fuse with t... Persistent ascending or descending mesocolon is an embryological anomaly that occurs during the final process of intestinal development in organogenesis.Specifically,the primitive dorsal mesocolon fails to fuse with the parietal peritoneum in the fifth month of gestation.Herein,we describe a case of ascending colon cancer with persistent ascending and descending mesocolon treated by laparoscopic right hemicolectomy.Preoperative computed tomography imaging of the abdomen demonstrated that the descending colon shifted at the midline of the abdomen and the sigmoid colon was located under the ascending colon.The detailed preoperative imaging examination revealed malpositioning of the large intestine and aided in the procedural planning.Because persistent mesocolon may result in the formation of abnormal adhesions,an accurate preoperative diagnosis is essential.We propose that it is important to consider this anomaly when making the preoperative imaging diagnosis to ensure a safe operation. 展开更多
关键词 Laparoscopic surgery Colon cancer Persistent descending mesocolon Persistent ascending mesocolon Mobile cecum
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创伤性下行性小脑幕裂孔疝的CT研究
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作者 刘慧敏 段承祥 《中国医学影像技术》 CSCD 1992年第4期19-21,共3页
下行性小脑幕裂孔疝(descending transtentorial herniation DTH)是颅脑创伤发展过程中一种紧急而严重的情况。CT可直接显示DTH的类型及脑干受损的严重程度,为及时诊断和治疗提供了依据。现将我们对99例由创伤引起的DTH的CT检查所见分... 下行性小脑幕裂孔疝(descending transtentorial herniation DTH)是颅脑创伤发展过程中一种紧急而严重的情况。CT可直接显示DTH的类型及脑干受损的严重程度,为及时诊断和治疗提供了依据。现将我们对99例由创伤引起的DTH的CT检查所见分析报告如下。 展开更多
关键词 小脑幕裂孔疝 CT研究 HERNIATION descending 中线结构移位 侧脑室 弥漫性脑肿胀 脑池 环池 脑挫裂伤
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Neural network based on adaptive chaotic gradient descending optimization algorithm and its application in matte converting process 被引量:3
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作者 胡志坤 彭小奇 桂卫华 《Journal of Central South University of Technology》 EI 2004年第2期216-219,共4页
An adaptive chaotic gradient descending optimization algorithm for single objective optimization was presented. A local minimum judged by two rules was obtained by an improved mutative-step gradient descending method.... An adaptive chaotic gradient descending optimization algorithm for single objective optimization was presented. A local minimum judged by two rules was obtained by an improved mutative-step gradient descending method. A new optimal minimum was obtained to replace the local minimum by mutative-scale chaotic search algorithm whose scales are magnified gradually from a small scale in order to escape local minima. The global optimal value was attained by repeatedly iterating. At last, a BP (back-propagation) neural network model for forecasting slag output in matte converting was established. The algorithm was used to train the weights of the BP neural network model. The simulation results with a training data set of 400 samples show that the training process can be finished within 300 steps to obtain the global optimal value, and escape local minima effectively. An optimization system for operation parameters, which includes the forecasting model, is achieved, in which the output of converter increases by 6.0%, and the amount of the treated cool materials rises by 7.8% in the matte converting process. 展开更多
关键词 matte converting chaotic search gradient descending neural network
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