Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CA...Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical fertilizer.Compared with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior kernels.These effects were largely due to the improved filling and starch accumulation of inferior kernels.However,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most cases.Leaf area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or OFCF2.Compared with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and DMA.Moreover,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N uptake.Analyses showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position effect.In conclusion,the combined application of 15-30%organic fertilizer and 70-85%chemical fertilizer alleviated the kernel position effect in summer maize by improving post-silking N uptake and DMA.These results provide new insights into how CAOFCF can be used to improve maize productivity.展开更多
BACKGROUND Intracranial hemorrhage after spinal surgery is a rare and devastating complication.AIM To investigate the economic burden,clinical characteristics,risk factors,and mechanisms of intracranial hemorrhage aft...BACKGROUND Intracranial hemorrhage after spinal surgery is a rare and devastating complication.AIM To investigate the economic burden,clinical characteristics,risk factors,and mechanisms of intracranial hemorrhage after spinal surgery.METHODS A retrospective cohort study was conducted from January 1,2015,to December 31,2022.Patients aged≥18 years,who had undergone spinal surgery were included.Intracranial hemorrhage patients were selected after spinal surgery during hospitalization.Based on the type of spinal surgery,patients with intracranial hemorrhage were randomly matched in a 1:5 ratio with control patients without intracranial hemorrhage.The patients'pre-,intra-,and post-operative data and clinical manifestations were recorded.RESULTS A total of 24472 patients underwent spinal surgery.Six patients(3 males and 3 females,average age 71.3 years)developed intracranial hemorrhage after posterior spinal fusion procedures,with an incidence of 0.025%(6/24472).The prevailing type of intracranial hemorrhage was cerebellar hemorrhage.Two patients had a poor clinical outcome.Based on the type of surgery,30 control patients were randomly matched in 1:5 ratio.The intracranial hemorrhage group showed significant differences compared with the control group with regard to age(71.33±7.45 years vs 58.39±8.07 years,P=0.001),previous history of cerebrovascular disease(50%vs 6.7%,P=0.024),spinal dura mater injury(50%vs 3.3%,P=0.010),hospital expenses(RMB 242119.1±87610.0 vs RMB 96290.7±32029.9,P=0.009),and discharge activity daily living score(40.00±25.88 vs 75.40±18.29,P=0.019).CONCLUSION The incidence of intracranial hemorrhage after spinal surgery was extremely low,with poor clinical outcomes.Patient age,previous stroke history,and dura mater damage were possible risk factors.It is suggested that spinal dura mater injury should be avoided during surgery in high-risk patients.展开更多
The Ni-based self-fluxing alloy coating containing RE was acquired by the technique of vacuum melting on the hypoeutectoid steel (Fe-0.45%C) matrix. By X-ray diffraction, SEM and EDX, the microstructure and phase stru...The Ni-based self-fluxing alloy coating containing RE was acquired by the technique of vacuum melting on the hypoeutectoid steel (Fe-0.45%C) matrix. By X-ray diffraction, SEM and EDX, the microstructure and phase structure of section of coating and the microstructure near the interface between coating and matrix were investigated, and the effect of RE on microstructure of coating was also discussed. The results show that the microstructure of the NiCrBSi alloy coating is composed of Ni-based solid solution and a lot of massive, globular and needle secondary phases CrB, Ni_3B, Cr_7C_3, Cr_(23)C_6 among the solid solution. The metallurgical binding between steel matrix and coating is realized. RE makes needle phase of alloy coating vanish. New phases of NiB and Cr_(6.5)Ni_(2.5)Si are precipitated from alloy coating, and secondary phases of alloy coating are sphericized. Consequently, RE also hinders the diffusion of Ni, Cr and Si atoms from coating to matrix and Fe atoms from matrix to coating, holds back the dilution of Fe for NiCrBSi alloy coating, and assures the chemical composition of the alloy coating.展开更多
Impaired amyloid-β clearance from the brain is a core pathological event in Alzheimer's disease.The therapeutic effect of current pharmacotherapies is unsatisfactory,and some treatments cause severe side effects.The...Impaired amyloid-β clearance from the brain is a core pathological event in Alzheimer's disease.The therapeutic effect of current pharmacotherapies is unsatisfactory,and some treatments cause severe side effects.The meningeal lymphatic vessels might be a new route for amyloid-β clearance.This study investigated whether promoting dural lymphangiogenesis facilitated the clearance of amyloid-β from the brain.First,human lymphatic endothelial cells were treated with 100 ng/m L recombinant human vascular endothelial growth factor-C(rh VEGF-C) protein.Light microscopy verified that rh VEGF-C,a specific ligand for vascular endothelial growth factor receptor-3(VEGFR-3),significantly promoted tube formation of human lymphatic endothelial cells in vitro.In an in vivo study,200 μg/m L rh VEGF-C was injected into the cisterna magna of APP/PS1 transgenic mice,once every 2 days,four times in total.Immunofluorescence staining demonstrated high levels of dural lymphangiogenesis in Alzheimer's disease mice.One week after rh VEGF-C administration,enzyme-linked immunosorbent assay results showed that levels of soluble amyloid-β were decreased in cerebrospinal fluid and brain.The Morris water maze test demonstrated that spatial cognition was restored.These results indicate that the upregulation of dural lymphangiogenesis facilities amyloid-β clearance from the brain of APP/PS1 mice,suggesting the potential of the VEGF-C/VEGFR-3 signaling pathway as a therapeutic target for Alzheimer's disease.展开更多
Recent studies have shown that nitric oxide (NO) can induce migraine attacks at three possible sites of action: nitroxidergic nerves, the vascular endothelium, and the central nervous system. Most previous studies ...Recent studies have shown that nitric oxide (NO) can induce migraine attacks at three possible sites of action: nitroxidergic nerves, the vascular endothelium, and the central nervous system. Most previous studies have focused on the former two sites of action. Several experiments using exogenic NO donors have suggested that nitroglycerin may induce migraine via central mechanisms. However, few studies have investigated the source of the NO involved in the central mechanisms of migraine. The present study used a cat model of migraine to represent migraine attacks in humans. We performed immunochemical staining of successive frozen sections of the brainstem and upper cervical spinal cord, and then used c-Fos protein expression to label nerve cell activation. We observed the effects of N^ω-nitro-L-arginine methyl ester (L-NAME), a non-selective nitric oxide synthase (NOS) inhibitor, and 7-nitroindozole (7-NI), a selective neuronal NOS inhibitor, on c-Fos and nNOS expression, which were induced by electrical stimulation to the dura mater near the superior sagittal sinus. The results demonstrated that c-Fos or nNOS immunoreactive cells was concentrated in the superficial layers (laminae Ⅰ and Ⅱ) of the spinal nucleus of trigeminal nerve. L-NAME and 7-NI pre-treatment significantly decreased c-Fos and neurogenic NOS expression; and there was a significant linear correlation between c-Fos and NOS expression (r = 0.858 2, P 〈 0.01). These findings suggest that neurogenic NO could facilitate migraine nociceptive transmission to second-order neurons of the trigeminal nerve. However, L-NAME and 7-NI may block the activation of neurons in the spinal nucleus of the trigeminal nerve by inhibiting NO synthesis, and thereby attenuate acute migraine attacks.展开更多
With chromium-hematoxylin staining, we found evidence for the existence of novel age-dependent network structures in the dura mater of rat brains. Under stereomicroscopy, we noticed that chromium-hematoxylin-stained t...With chromium-hematoxylin staining, we found evidence for the existence of novel age-dependent network structures in the dura mater of rat brains. Under stereomicroscopy, we noticed that chromium-hematoxylin-stained threadlike structures, which were barely observable in 1-weekold rats, were networked in specific areas of the brain, for example, the lateral lobes and the cerebella, in 4-week-old rats. In 7-week-old rats, those structures were found to have become larger and better networked. With phase contrast microscopy, we found that in 1-week-old rats, chromium-hematoxylin-stained granules were scattered in the same areas of the brain in which the network structures would later be observed in the 4- and 7-week-old rats. Such age-dependent network structures were examined by using optical and transmission electron microscopy, and the following results were obtained. The scattered granules fused into networks with increasing age. Cross-sections of the age-dependent network structures demonstrated heavily-stained basophilic substructures. Transmission electron microscopy revealed the basophilic substructures to be clusters with high electron densities consisting of nanosized particles. We report these data as evidence for the existence of age-dependent network structures in the dura mater, we discuss their putative functions of age-dependent network structures beyond the general concept of the dura mater as a supporting matrix.展开更多
BACKGROUND: This paper describes histomorphologic studies on arachnoid granulations in rats, which have not been investigated in China to our knowledge. OBJECTIVE: To observe the distribution of intracranial arachno...BACKGROUND: This paper describes histomorphologic studies on arachnoid granulations in rats, which have not been investigated in China to our knowledge. OBJECTIVE: To observe the distribution of intracranial arachnoid granulations in rats. DESIGN, TIME AND SETTING: The observational experiment was performed in the Academy of Life Sciences of Shandong Taishan Medical College from May to August 2004. MATERIALS: Thirty healthy adult Wistar rats (3-4 months old) of SPF grade, equal numbers of each sex, were selected for this study. Methylene blue parenteral solution was provided by Jiangsu Jichuan Pharmaceutical Company (China), and an optical microscope (Type: CH20; Olympus Co. Ltd., Japan) was used for observation of the histomorphology of the arachnoid granulations. METHOD: Injection of methylene blue parenteral solution into the cerebellomedullary cistern of rats. MAIN OUTCOME MEASURE: The blue stained parts of the lateral sinus were sectioned, stained by hematoxylin and eosin, and then observed under the microscope. RESULTS: The cavitas subarachnoidealis had extensive blue staining after methylene blue injection, while the arachnoid and dura were without dye accumulation. The blue dye indicated the location of the arachnoid granulations. The location of these granulations was fixed, mainly in the lateral sinus at both sides of confluence within 4 mm of the internal jugular vein. CONCLUSION: The arachnoid granulations of the rat were located mainly in the lateral sinuses of the dura mater.展开更多
To explore the effect of the location of a visual stimulus on neural responses in the primary visual cortex (V1), a micro-electromechanical system-based microelectrode array with nine channels was implanted on the c...To explore the effect of the location of a visual stimulus on neural responses in the primary visual cortex (V1), a micro-electromechanical system-based microelectrode array with nine channels was implanted on the cerebral dura mater of V1 in adult cats. 2 Hz pattern reversal checkerboard stimul were used to stimulate the four visual quadrants (i.e., upper left, upper right, lower left, and lower right fields). The results showed that there was a N75 component of the visual evoked potential around 50-80 ms after the onset of a checkerboard stimulus, and the onset of these N75 peaks varied with different stimulus locations. The checkerboard stimuli Jnduced shorter latencJes in the contralateral V1 than in the ipsilateral V1, while the checkerboard stimulus in the upper half visual field induced shorter latencies for N75. These results suggested that the pattern-reversal stimuli induced neural activities in V1 that can be recorded with multichannel microelectrodes, and more detailed temporal and spatial properties can be measured.展开更多
The 19 strains of Panicillium cyclopium were isolatedfrom the cereals of Linxian were cultured in Raulin-Thomliquid medium,25℃ incubated 14 daies still condition.The liquids and membrans of the cultures were extracte...The 19 strains of Panicillium cyclopium were isolatedfrom the cereals of Linxian were cultured in Raulin-Thomliquid medium,25℃ incubated 14 daies still condition.The liquids and membrans of the cultures were extractedrespectively.the extracts were examinated in 4 mutationtasts as follows.展开更多
BACKGROUND Rhabdomyosarcoma(RMS)is a rare malignant tumor of mesenchymal origin that mainly affects children.Spindle cell/sclerosing RMS(SSRMS)is even rarer.It is a new subtype that was added to the World Health Organ...BACKGROUND Rhabdomyosarcoma(RMS)is a rare malignant tumor of mesenchymal origin that mainly affects children.Spindle cell/sclerosing RMS(SSRMS)is even rarer.It is a new subtype that was added to the World Health Organization disease classification in 2013.To the best of our knowledge,this is the first reported case of adult SSRMS disease classification originating in the temporal muscle.CASE SUMMARY SSRMS originating in the temporal muscle of a male adult enlarged rapidly,destroyed the skull,and invaded the meninges.The tumor was completely removed,and the postoperative pathological diagnosis was SSRMS.Postoperative recovery was good and chemotherapy and radiotherapy were given after the operation.Followed up for 3 mo,no tumor recurred.CONCLUSION RMS is one of the differential diagnoses for head soft tissue tumors with shortterm enlargement and skull infiltration.Preoperative computed tomography or magnetic resonance imaging is necessary for early detection of tumor invasion of the skull and brain tissue.展开更多
Acidium mandelicum(AM) was used as an urinaryantiseptics in the 1930’.Recently,through laboratoryexperiment and clinical use,we have found AM tohave spermicide effect and possess special contra-ceptive mechanism.Thus...Acidium mandelicum(AM) was used as an urinaryantiseptics in the 1930’.Recently,through laboratoryexperiment and clinical use,we have found AM tohave spermicide effect and possess special contra-ceptive mechanism.Thus,it may be a reliable contra-ceptive.As any mutagenicity-positive material展开更多
The Fe-Ti-N mater alloy was prepared through the in-situ reaction of nitrogen gas with the Fe-Ti melt.Scanning electron microscope results show that the particles uniformly distributed in the iron matrix were TiN.The ...The Fe-Ti-N mater alloy was prepared through the in-situ reaction of nitrogen gas with the Fe-Ti melt.Scanning electron microscope results show that the particles uniformly distributed in the iron matrix were TiN.The deliberately prepared Fe-Ti-N master alloy was employed for the 409L ferritic stainless steel in an attempt to refine the as-cast solidification structure.It was found that the effectiveness of Fe-Ti-N master alloy on refining of the as-cast 409L ferritic stainless steel was affected by addition level,holding time and melts temperature.It was found that the average equiaxed grain size decreased from 1 503μm to 303μm,the proportion of equiaxed grain zone increased from 14%to 100%with increasing the Fe-Ti-N master alloy addition level to 2.5%.The proportion of equiaxed grain decreased from 85%to 4%as the solidification temperature increased from 1 803 K to 1 883 K.When the holding time reached to 8min,the solidification structures of 409L ferritic stainless steel show extreme points in the proportion of equiaxed grain.It is clear that the grain refining efficiency gradually fade away with the increasing of the holding time at the very beginning.However,when the holding time continues to increase and exceeds the extreme point, the grain refining efficiency of the Fe-Ti-N master alloy recovered to a certain degree.The experimental results mentioned above have been analyzed in terms of thermodynamics.Under appropriate conditions,the Fe-Ti-N master alloy used for grain refinement of the solidification structure of 409L ferritic stainless steel may have good prospects for industrial applications.展开更多
The dura mater is of similar embryological origin to the fascial organ. It contains several fibroblasts which make the dura mater a flexible structure. Dura mater is the outermost of the three layers of meninges, a th...The dura mater is of similar embryological origin to the fascial organ. It contains several fibroblasts which make the dura mater a flexible structure. Dura mater is the outermost of the three layers of meninges, a thick and rigid inelastic membrane that covers the brain and spinal cord and that is impermeable to the cerebrospinal fluid. The cranial dura mater in certain respects differs anatomically from the dura material in the spinal cord, and it is important to classify them separately. This article reviews the anatomical structure of spinal and cranial dura mater and its anatomy with muscle, fascia, bone structure and ligaments. Dura mater is a structure in the body that is connected with systemic functions.展开更多
Intradural disc herniation is rare and often diagnosed during surgery. We present two patients with the disease, one with an intra-arachnoid type, the other with an extra-arachnoid location. The teaching point of thos...Intradural disc herniation is rare and often diagnosed during surgery. We present two patients with the disease, one with an intra-arachnoid type, the other with an extra-arachnoid location. The teaching point of those cases is that this very frequent pathology can take a variety of forms, depending on the structures that are infiltrated. The key point in correctly diagnosing the intradural disc herniation is to look at the angle between the fragment and the dura. Is it pushing it (as in the usual disc herniation), embedded in it (those with the extra-arachnoid type) or does it go through to fall into the CSF (In the intra-arachnoid type)? It could be diagnosed on MRI preoperatively. Contrary to many published cases of intradural disc herniation, the two patients could be managed non-surgically.展开更多
BEIJING Universityls one ofthe better-known Institutesof higher learning in China,an educational and research centerdealingwith a variety of subjects,Including science and technology,the humanities,sociology,adminis-t...BEIJING Universityls one ofthe better-known Institutesof higher learning in China,an educational and research centerdealingwith a variety of subjects,Including science and technology,the humanities,sociology,adminis-tration and pedagogy.Founded 95years ago,it is alma mater to severalgenerations of fine scholars.The Birth of BeijingUniversityImperial College,the predecessor of Beliing University,founded inthe Reform Movement of 1898,wasa combination of Chinese and West-展开更多
Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis...Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis Omega3 DuraTM). In an ovine model a craniotomy under general anaesthesia was performed. A defect was produced in the dural covering of approximately 1 × 2 cm and closed with an onlay technique, with Kerecis Omega3 Dura. The bone defect was covered with the bony flap and the overlying tissues closed in layers. At 2, 5, 8 and 11 weeks the sheep underwent MRI scanning followed by euthanasia, necropsy and histological assessment. MRI images taken at 2, 5, 8 and 11 weeks showed initially moderate inflammatory response, which diminished over time, and at 11 weeks no evidence of inflammation existed. There was evidence of cerebrospinal fluid leakage at no time point. Necropsy revealed some adhesions at 5 and 8 weeks, in particular at 5 weeks, but at 11 weeks there were no adhesions found. From 2 - 11 weeks, there was evidence of initially an inflammatory reaction followed by neodura formation at the defect site through cellular ingrowth and remodeling of the acellular fish skin. Histology showed a histiocytic foreign body reaction initially that subsided over time. As early as 8 weeks there was evidence of neodura formation and by 11 weeks there was a minimal inflammatory response with an intact neodura formed. In this pilot study the Kerecis Omega3 Dura patches performed in a safe and efficacious manner. This new material needs to be fully assessed and compared with other products that are currently on the market in a larger scale animal study.展开更多
基金financially supported by the HAAFS Science and Technology Innovation Special Project China(2022KJCXZX-LYS-9)the Natural Science Foundation of Hebei Province China(C2021301004)the Key Research and Dvelopment Program of Hebei Province China(20326401D)。
文摘Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical fertilizer.Compared with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior kernels.These effects were largely due to the improved filling and starch accumulation of inferior kernels.However,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most cases.Leaf area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or OFCF2.Compared with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and DMA.Moreover,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N uptake.Analyses showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position effect.In conclusion,the combined application of 15-30%organic fertilizer and 70-85%chemical fertilizer alleviated the kernel position effect in summer maize by improving post-silking N uptake and DMA.These results provide new insights into how CAOFCF can be used to improve maize productivity.
基金“Xue Ke Xin Xing”of Beijing Jishuitan Hospital,Beijing,China,No.XKXX201611。
文摘BACKGROUND Intracranial hemorrhage after spinal surgery is a rare and devastating complication.AIM To investigate the economic burden,clinical characteristics,risk factors,and mechanisms of intracranial hemorrhage after spinal surgery.METHODS A retrospective cohort study was conducted from January 1,2015,to December 31,2022.Patients aged≥18 years,who had undergone spinal surgery were included.Intracranial hemorrhage patients were selected after spinal surgery during hospitalization.Based on the type of spinal surgery,patients with intracranial hemorrhage were randomly matched in a 1:5 ratio with control patients without intracranial hemorrhage.The patients'pre-,intra-,and post-operative data and clinical manifestations were recorded.RESULTS A total of 24472 patients underwent spinal surgery.Six patients(3 males and 3 females,average age 71.3 years)developed intracranial hemorrhage after posterior spinal fusion procedures,with an incidence of 0.025%(6/24472).The prevailing type of intracranial hemorrhage was cerebellar hemorrhage.Two patients had a poor clinical outcome.Based on the type of surgery,30 control patients were randomly matched in 1:5 ratio.The intracranial hemorrhage group showed significant differences compared with the control group with regard to age(71.33±7.45 years vs 58.39±8.07 years,P=0.001),previous history of cerebrovascular disease(50%vs 6.7%,P=0.024),spinal dura mater injury(50%vs 3.3%,P=0.010),hospital expenses(RMB 242119.1±87610.0 vs RMB 96290.7±32029.9,P=0.009),and discharge activity daily living score(40.00±25.88 vs 75.40±18.29,P=0.019).CONCLUSION The incidence of intracranial hemorrhage after spinal surgery was extremely low,with poor clinical outcomes.Patient age,previous stroke history,and dura mater damage were possible risk factors.It is suggested that spinal dura mater injury should be avoided during surgery in high-risk patients.
文摘The Ni-based self-fluxing alloy coating containing RE was acquired by the technique of vacuum melting on the hypoeutectoid steel (Fe-0.45%C) matrix. By X-ray diffraction, SEM and EDX, the microstructure and phase structure of section of coating and the microstructure near the interface between coating and matrix were investigated, and the effect of RE on microstructure of coating was also discussed. The results show that the microstructure of the NiCrBSi alloy coating is composed of Ni-based solid solution and a lot of massive, globular and needle secondary phases CrB, Ni_3B, Cr_7C_3, Cr_(23)C_6 among the solid solution. The metallurgical binding between steel matrix and coating is realized. RE makes needle phase of alloy coating vanish. New phases of NiB and Cr_(6.5)Ni_(2.5)Si are precipitated from alloy coating, and secondary phases of alloy coating are sphericized. Consequently, RE also hinders the diffusion of Ni, Cr and Si atoms from coating to matrix and Fe atoms from matrix to coating, holds back the dilution of Fe for NiCrBSi alloy coating, and assures the chemical composition of the alloy coating.
基金supported by the National Natural Science Foundation of China,No.31371130 and 31600836the Special Foundation of Education Department of Guangdong Province of China+1 种基金the Medical Scientific Research Foundation of Guangdong Province of China,No.2013-159the Foundation of Medical Science and Technology Research of Guangdong Province of China,No.A2016273
文摘Impaired amyloid-β clearance from the brain is a core pathological event in Alzheimer's disease.The therapeutic effect of current pharmacotherapies is unsatisfactory,and some treatments cause severe side effects.The meningeal lymphatic vessels might be a new route for amyloid-β clearance.This study investigated whether promoting dural lymphangiogenesis facilitated the clearance of amyloid-β from the brain.First,human lymphatic endothelial cells were treated with 100 ng/m L recombinant human vascular endothelial growth factor-C(rh VEGF-C) protein.Light microscopy verified that rh VEGF-C,a specific ligand for vascular endothelial growth factor receptor-3(VEGFR-3),significantly promoted tube formation of human lymphatic endothelial cells in vitro.In an in vivo study,200 μg/m L rh VEGF-C was injected into the cisterna magna of APP/PS1 transgenic mice,once every 2 days,four times in total.Immunofluorescence staining demonstrated high levels of dural lymphangiogenesis in Alzheimer's disease mice.One week after rh VEGF-C administration,enzyme-linked immunosorbent assay results showed that levels of soluble amyloid-β were decreased in cerebrospinal fluid and brain.The Morris water maze test demonstrated that spatial cognition was restored.These results indicate that the upregulation of dural lymphangiogenesis facilities amyloid-β clearance from the brain of APP/PS1 mice,suggesting the potential of the VEGF-C/VEGFR-3 signaling pathway as a therapeutic target for Alzheimer's disease.
文摘Recent studies have shown that nitric oxide (NO) can induce migraine attacks at three possible sites of action: nitroxidergic nerves, the vascular endothelium, and the central nervous system. Most previous studies have focused on the former two sites of action. Several experiments using exogenic NO donors have suggested that nitroglycerin may induce migraine via central mechanisms. However, few studies have investigated the source of the NO involved in the central mechanisms of migraine. The present study used a cat model of migraine to represent migraine attacks in humans. We performed immunochemical staining of successive frozen sections of the brainstem and upper cervical spinal cord, and then used c-Fos protein expression to label nerve cell activation. We observed the effects of N^ω-nitro-L-arginine methyl ester (L-NAME), a non-selective nitric oxide synthase (NOS) inhibitor, and 7-nitroindozole (7-NI), a selective neuronal NOS inhibitor, on c-Fos and nNOS expression, which were induced by electrical stimulation to the dura mater near the superior sagittal sinus. The results demonstrated that c-Fos or nNOS immunoreactive cells was concentrated in the superficial layers (laminae Ⅰ and Ⅱ) of the spinal nucleus of trigeminal nerve. L-NAME and 7-NI pre-treatment significantly decreased c-Fos and neurogenic NOS expression; and there was a significant linear correlation between c-Fos and NOS expression (r = 0.858 2, P 〈 0.01). These findings suggest that neurogenic NO could facilitate migraine nociceptive transmission to second-order neurons of the trigeminal nerve. However, L-NAME and 7-NI may block the activation of neurons in the spinal nucleus of the trigeminal nerve by inhibiting NO synthesis, and thereby attenuate acute migraine attacks.
基金supported by Global Ph.D.Fellowship Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2014H1A2A1020588)by Korea Atomic Energy Research Institute,by a Korean Pharmacopuncture Foundation Grant funded by the Korean Pharmacopuncture Institute(KPI-2014-010)by the grant K13290 of KIOM and by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future Planning(2013R1A1A2021577)
文摘With chromium-hematoxylin staining, we found evidence for the existence of novel age-dependent network structures in the dura mater of rat brains. Under stereomicroscopy, we noticed that chromium-hematoxylin-stained threadlike structures, which were barely observable in 1-weekold rats, were networked in specific areas of the brain, for example, the lateral lobes and the cerebella, in 4-week-old rats. In 7-week-old rats, those structures were found to have become larger and better networked. With phase contrast microscopy, we found that in 1-week-old rats, chromium-hematoxylin-stained granules were scattered in the same areas of the brain in which the network structures would later be observed in the 4- and 7-week-old rats. Such age-dependent network structures were examined by using optical and transmission electron microscopy, and the following results were obtained. The scattered granules fused into networks with increasing age. Cross-sections of the age-dependent network structures demonstrated heavily-stained basophilic substructures. Transmission electron microscopy revealed the basophilic substructures to be clusters with high electron densities consisting of nanosized particles. We report these data as evidence for the existence of age-dependent network structures in the dura mater, we discuss their putative functions of age-dependent network structures beyond the general concept of the dura mater as a supporting matrix.
文摘BACKGROUND: This paper describes histomorphologic studies on arachnoid granulations in rats, which have not been investigated in China to our knowledge. OBJECTIVE: To observe the distribution of intracranial arachnoid granulations in rats. DESIGN, TIME AND SETTING: The observational experiment was performed in the Academy of Life Sciences of Shandong Taishan Medical College from May to August 2004. MATERIALS: Thirty healthy adult Wistar rats (3-4 months old) of SPF grade, equal numbers of each sex, were selected for this study. Methylene blue parenteral solution was provided by Jiangsu Jichuan Pharmaceutical Company (China), and an optical microscope (Type: CH20; Olympus Co. Ltd., Japan) was used for observation of the histomorphology of the arachnoid granulations. METHOD: Injection of methylene blue parenteral solution into the cerebellomedullary cistern of rats. MAIN OUTCOME MEASURE: The blue stained parts of the lateral sinus were sectioned, stained by hematoxylin and eosin, and then observed under the microscope. RESULTS: The cavitas subarachnoidealis had extensive blue staining after methylene blue injection, while the arachnoid and dura were without dye accumulation. The blue dye indicated the location of the arachnoid granulations. The location of these granulations was fixed, mainly in the lateral sinus at both sides of confluence within 4 mm of the internal jugular vein. CONCLUSION: The arachnoid granulations of the rat were located mainly in the lateral sinuses of the dura mater.
基金the National High Technology and Development Program of China, No. 2007AA04Z324the National Natural Science Foundation of China, No. 30970758, 31070882
文摘To explore the effect of the location of a visual stimulus on neural responses in the primary visual cortex (V1), a micro-electromechanical system-based microelectrode array with nine channels was implanted on the cerebral dura mater of V1 in adult cats. 2 Hz pattern reversal checkerboard stimul were used to stimulate the four visual quadrants (i.e., upper left, upper right, lower left, and lower right fields). The results showed that there was a N75 component of the visual evoked potential around 50-80 ms after the onset of a checkerboard stimulus, and the onset of these N75 peaks varied with different stimulus locations. The checkerboard stimuli Jnduced shorter latencJes in the contralateral V1 than in the ipsilateral V1, while the checkerboard stimulus in the upper half visual field induced shorter latencies for N75. These results suggested that the pattern-reversal stimuli induced neural activities in V1 that can be recorded with multichannel microelectrodes, and more detailed temporal and spatial properties can be measured.
文摘The 19 strains of Panicillium cyclopium were isolatedfrom the cereals of Linxian were cultured in Raulin-Thomliquid medium,25℃ incubated 14 daies still condition.The liquids and membrans of the cultures were extractedrespectively.the extracts were examinated in 4 mutationtasts as follows.
文摘BACKGROUND Rhabdomyosarcoma(RMS)is a rare malignant tumor of mesenchymal origin that mainly affects children.Spindle cell/sclerosing RMS(SSRMS)is even rarer.It is a new subtype that was added to the World Health Organization disease classification in 2013.To the best of our knowledge,this is the first reported case of adult SSRMS disease classification originating in the temporal muscle.CASE SUMMARY SSRMS originating in the temporal muscle of a male adult enlarged rapidly,destroyed the skull,and invaded the meninges.The tumor was completely removed,and the postoperative pathological diagnosis was SSRMS.Postoperative recovery was good and chemotherapy and radiotherapy were given after the operation.Followed up for 3 mo,no tumor recurred.CONCLUSION RMS is one of the differential diagnoses for head soft tissue tumors with shortterm enlargement and skull infiltration.Preoperative computed tomography or magnetic resonance imaging is necessary for early detection of tumor invasion of the skull and brain tissue.
文摘Acidium mandelicum(AM) was used as an urinaryantiseptics in the 1930’.Recently,through laboratoryexperiment and clinical use,we have found AM tohave spermicide effect and possess special contra-ceptive mechanism.Thus,it may be a reliable contra-ceptive.As any mutagenicity-positive material
文摘The Fe-Ti-N mater alloy was prepared through the in-situ reaction of nitrogen gas with the Fe-Ti melt.Scanning electron microscope results show that the particles uniformly distributed in the iron matrix were TiN.The deliberately prepared Fe-Ti-N master alloy was employed for the 409L ferritic stainless steel in an attempt to refine the as-cast solidification structure.It was found that the effectiveness of Fe-Ti-N master alloy on refining of the as-cast 409L ferritic stainless steel was affected by addition level,holding time and melts temperature.It was found that the average equiaxed grain size decreased from 1 503μm to 303μm,the proportion of equiaxed grain zone increased from 14%to 100%with increasing the Fe-Ti-N master alloy addition level to 2.5%.The proportion of equiaxed grain decreased from 85%to 4%as the solidification temperature increased from 1 803 K to 1 883 K.When the holding time reached to 8min,the solidification structures of 409L ferritic stainless steel show extreme points in the proportion of equiaxed grain.It is clear that the grain refining efficiency gradually fade away with the increasing of the holding time at the very beginning.However,when the holding time continues to increase and exceeds the extreme point, the grain refining efficiency of the Fe-Ti-N master alloy recovered to a certain degree.The experimental results mentioned above have been analyzed in terms of thermodynamics.Under appropriate conditions,the Fe-Ti-N master alloy used for grain refinement of the solidification structure of 409L ferritic stainless steel may have good prospects for industrial applications.
文摘The dura mater is of similar embryological origin to the fascial organ. It contains several fibroblasts which make the dura mater a flexible structure. Dura mater is the outermost of the three layers of meninges, a thick and rigid inelastic membrane that covers the brain and spinal cord and that is impermeable to the cerebrospinal fluid. The cranial dura mater in certain respects differs anatomically from the dura material in the spinal cord, and it is important to classify them separately. This article reviews the anatomical structure of spinal and cranial dura mater and its anatomy with muscle, fascia, bone structure and ligaments. Dura mater is a structure in the body that is connected with systemic functions.
文摘Intradural disc herniation is rare and often diagnosed during surgery. We present two patients with the disease, one with an intra-arachnoid type, the other with an extra-arachnoid location. The teaching point of those cases is that this very frequent pathology can take a variety of forms, depending on the structures that are infiltrated. The key point in correctly diagnosing the intradural disc herniation is to look at the angle between the fragment and the dura. Is it pushing it (as in the usual disc herniation), embedded in it (those with the extra-arachnoid type) or does it go through to fall into the CSF (In the intra-arachnoid type)? It could be diagnosed on MRI preoperatively. Contrary to many published cases of intradural disc herniation, the two patients could be managed non-surgically.
文摘BEIJING Universityls one ofthe better-known Institutesof higher learning in China,an educational and research centerdealingwith a variety of subjects,Including science and technology,the humanities,sociology,adminis-tration and pedagogy.Founded 95years ago,it is alma mater to severalgenerations of fine scholars.The Birth of BeijingUniversityImperial College,the predecessor of Beliing University,founded inthe Reform Movement of 1898,wasa combination of Chinese and West-
文摘Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis Omega3 DuraTM). In an ovine model a craniotomy under general anaesthesia was performed. A defect was produced in the dural covering of approximately 1 × 2 cm and closed with an onlay technique, with Kerecis Omega3 Dura. The bone defect was covered with the bony flap and the overlying tissues closed in layers. At 2, 5, 8 and 11 weeks the sheep underwent MRI scanning followed by euthanasia, necropsy and histological assessment. MRI images taken at 2, 5, 8 and 11 weeks showed initially moderate inflammatory response, which diminished over time, and at 11 weeks no evidence of inflammation existed. There was evidence of cerebrospinal fluid leakage at no time point. Necropsy revealed some adhesions at 5 and 8 weeks, in particular at 5 weeks, but at 11 weeks there were no adhesions found. From 2 - 11 weeks, there was evidence of initially an inflammatory reaction followed by neodura formation at the defect site through cellular ingrowth and remodeling of the acellular fish skin. Histology showed a histiocytic foreign body reaction initially that subsided over time. As early as 8 weeks there was evidence of neodura formation and by 11 weeks there was a minimal inflammatory response with an intact neodura formed. In this pilot study the Kerecis Omega3 Dura patches performed in a safe and efficacious manner. This new material needs to be fully assessed and compared with other products that are currently on the market in a larger scale animal study.