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61.
Dog pancreatic islets isolated by an enzymatic digestion method were encapsulated in an alginate-poly L-lysine-alginate membrane. These microencapsulated pancreatic islets were cultured in vitro to study their ability of insulin secretion. Portions of these in vitro-cultured microencapsulated pancreatic islets were taken out for a viability dye exclusion study as well as for pathologic studies to correlate them with insulin secretion ability. We found that there was a strong correlation between them. Good insulin-secreting microcapsules showed well-preserved cell membranes and beta-cell granules. An in vitro culture for one to two days in RPMI-1640 made the islets more stable, the cellular surface became smoother and the beta-granules were in better shape. The microencapsulated pancreatic islets were also injected into the peritoneum of streptozotocin-induced diabetic CDF1 mice. Blood glucose levels dropped and stayed low for up to 60 days. But, when non-encapsulated dog pancreatic islets were used, the blood glucose levels remained low for only about 14 days. A small portion of the injected microcapsules were washed out at specific times for pathologic study. Up to 28 days after injection, only a few of the injected microcapsules showed pericapsular cellular infiltrate. However, after 56 days, most of the microcapsules showed dense pericapsular cellular infiltrate. Immunohistochemical analysis of these infiltrates showed that the majority of cells were fibroblasts and macrophages. Most of the cells located in the inner portion of the infiltrate were fibroblasts, while the macrophages were located mainly on the outer portion. Both scanning and transmission electron microscopy showed that the surface of the microcapsule outer wall was much smoother than the inner wall. The size of the microcapsules was approximately 0.6-0.8 mm and the thickness of the wall measured around 10 nm. The smaller the microcapsule is, the less chance there is of rupture with release of the xenographic islets. Once the wall of the transplanted microcapsules was ruptured, the inner surface showed more increased inflammatory cell and fibroblast infiltration than the outer surface.  相似文献   
62.
We report a patient with a posterior inferior cerebellar artery (PICA) aneurysm and an incidental facial nerve schwannoma at the cerebellopontine angle (CPA). A 46-year-old woman presented with the sudden onset of a severe headache, nausea, and vomiting. She had no other abnormal neurological symptoms and signs. Computed tomography (CT) showed hemorrhage in the fourth ventricle. Cerebral angiography demonstrated an aneurysm arising from the tonsillomedullary segment of the left PICA. A facial nerve schwannoma was incidentally found as the aneurysm was being clipped. The aneurysm was clipped via a left transcondylar approach. Subsequently, the schwannoma (2 x 3 x 2 mm) was resected from the facial nerve fascicles, and the facial nerve was preserved. Postoperatively, the patient developed mild to moderate dysfunction of the facial nerve (House-Brackmann grade III [H-B III]) but her hearing was intact. Both a facial nerve schwannoma involving the CPA and an aneurysm involving the PICA can be managed through the transcondylar approach. An asymptomatic facial nerve schwannoma can be resected safely with minimal facial nerve dysfunction.  相似文献   
63.
BACKGROUND CONTEXT: Although crystal deposition in cartilage and synovial fluid has received much attention, crystal formation and the role that crystal deposits play are virtually unexplored in the intervertebral disc. In articular cartilage matrix, crystal deposits are associated with altered extracellular matrix (ECM) and cell phenotypic features, but crystal deposition in the human intervertebral disc has received much less attention. PURPOSE: To determine the incidence of crystal deposits in the annulus and to evaluate associated disc cell and ECM features. STUDY DESIGN/SETTING: Human intervertebral disc annulus tissue was obtained in a prospective study of the presence of crystals in the disc ECM. Human Subjects Institutional Review Board approved experimental studies. PATIENT SAMPLE: Two hundred eight sequential disc specimens were submitted from surgical disc procedures performed on individuals with herniated discs, degenerative disc disease, or recurrent disc herniation. During this same time period, three disc specimens were received from nonsurgical donors and added to the study population. OUTCOME MEASURES: Histologic features with special attention to crystal deposition. METHODS: Specimens were processed undecalcified and examined for the histologic presence of crystal deposits and ECM features around the crystals. RESULTS: The proportion of specimens containing crystals was determined to be 14.7%; crystals displayed varying sizes, morphology, and polarized light birefringence features. Pyrophosphate crystals were most common, but oxalate-like crystals were also present. ECM in crystal regions showed previously recognized alterations. CONCLUSIONS: This study shows that the incidence of crystal deposits in discs is approximately 15% and is thus a relatively common occurrence. These data are important because masses of crystals not only disrupt disc ECM but may also accelerate preexisting degenerative changes via an elevation in matrix metalloproteinases (as previously recognized in cartilage). Because failure of the structural integrity of the disc can result in annular tears and subsequent disc herniation, the mechanisms of crystal formation and the relationship between crystals and disc degeneration merit further investigations.  相似文献   
64.
458例尿路结石成分分析   总被引:4,自引:1,他引:3  
目的 探讨西安地区尿路结石的成分状况,为临床防治提供帮助。方法对458例尿路结石标本进行化学成分测定,并结合临床资料进行比较。结果尿路结石男性发病多于女性,男、女比为2.1:1,20一50岁为高发年龄,上尿路结石明显多于下尿路结石,上、下尿路结石之比为10.5:1。结石成分以混合结石占多数,为325例(71%),其中以草酸钙,磷酸钙与尿酸的混合结石为主。对比混合性结石及单纯性结石发现,各种成分所占比例基本一致。结论结石成分分析对于了解结石成因、预防结石形成和复发具有重要的意义。  相似文献   
65.
颅内生殖细胞瘤综合治疗   总被引:4,自引:0,他引:4  
报告50例颅内生殖细胞瘤,手术治疗19例,放射治疗43例。综合治疗后临床症状改善41例,无效2例。随访32例,其中恢复正常工作或学习者14例,生活能自理12例,生活部分需人帮助4例,死亡2例。5年生存率为50%。推荐放疗为首选治疗手段,并对合并颅内压增高及多发性、复发性肿瘤的治疗作了讨论。  相似文献   
66.
The blocking effects of d-diltiazem, its metabolites, deacetyl-d-diltiazem (d-M1), deacetyl-N-demethyl-d-diltiazem (d-M2), deacetyl-O-demethyl-d-diltiazem (d-M4) and deacetyl-N, O-demethyl-d-diltiazem (d-M6) and 1-diltiazem were investigated on the voltage-gated calcium current (ICa) of an Achatina neurone. Based on the IC50 values, the order of potency was: d-diltiazem (0.426 mM), d-M2 (0.456), d-M1 (0.491), 1-diltiazem (0.759) greater than d-M4 (1.212) greater than d-M6 (greater than 2.000). Assuming that the IC50 reflects the KD for resting Ca2+ channels (Kr), steady state activation studies gave KD values for the inactivated channels (Ki) and Kr/Ki ratios of 0.122 mM (Ki) and 3.52 (Kr/Ki) (d-diltiazem), 0.112 and 6.98 (1-diltiazem), 0.083 and 6.07 (d-M1) and 0.156 and 2.97 (d-M2). All drugs tested showed a certain degree of voltage-dependence. The further percentage reduction in the normalized ICa after high frequency stimulation demonstrated the use-dependence of: 1-diltiazem (27.5%), d-diltiazem (26.3) greater than d-M2 (19.2) greater than d-M1 (16.7) greater than d-M6 (9.8). The voltage- and use-dependence of these drugs are consistent with their Ca2+ antagonistic properties.  相似文献   
67.
孙世荣  孙晓庆 《河北医学》1996,2(4):299-301
在山羊MODS的模型上,观察了血浆TNF与MODS的关系,32只山羊分为三组:失血性休克组(H);门静脉毒素血症组(E);失血性休克+内毒素血症组(M)。结果表明,三组动物血浆TNF均见升高,M组最明显。动物死亡率及MODS的发生率也是M组最高。可以认为TNF持续升高导致MOD发生发展的重要因素之一。  相似文献   
68.
A tissue equivalent phantom was used in the study and absored x-ray doses.It measuring for some important organs of head and neck by four routive sialography methods (panoramic conventional x-ray radioagraphy,tomography,fluoroscope,CT) and also the X-ray absorbed doses of thyroid and len when lead containing loop and spectacles of head containing glass were used for prevention.All the data were processed statistically and a compartive study of absorbed x-ray doses of four sialography methods:Doses of submandibular gland were higher in CT,tomography and fluoroscope among them,CT was the highest indicating that it was superior to other methods for accurately locating that it was superior to other methods for accurately locating the within-gland tumor.Fluoroscope will be use more frequently in clinic,because it can observe the living gland panoramic and normal radiography can be used routinely because they had the minimum doses in measured organs.2.The absorbed x-ray doses of len and thyroid decreased by 93%-% when prevention was taken in CT or fluoroscope,65%-85% doses was decreased in normal radiography or panoramic with prevention.  相似文献   
69.
为了探索单疱病毒性角膜炎的发病机制和快速诊断HSK。方法应用多聚酶链反应对感染的HSK的20只纯新西兰白兔和60例HSK患者的角膜进行了单疱病毒-1-DNA检测。结果急性感染期的5只兔角膜和12只人角膜均阳性;用稳定期45d的兔角供体行部分穿透性角膜移植术,术后50d10只兔角膜中7只阳性,稳定期6个月-6年的18只人角膜片,12只阳性;30例临床可疑HSK角膜刮取物,26例阳性;5只未感染HSK  相似文献   
70.
Chronic Ethanol Inhibits Inositol Metabolism in Specific Brain Regions   总被引:1,自引:0,他引:1  
Many neurotransmitters and hormones in the nervous system transmit signals through receptors coupled to the poly-phosphoinositide (PI) signaling pathway. In this study, an in vivo protocol with (3H]inositol was used to examine the effect of chronic ethanol administration on inositol metabolism and poly-PI turnover in the cerebral cortex, hippocampus, and cerebellum of mouse brain. C57BL/6 mice were given a nutritionally complete liquid diet containing either ethanol (5%, w/v) or isocaloric sucrose for 2 months. Mice were injected intracerebrally with rH]inositol; after 16 or 24 hr, they were injected intraperitoneally with lithium (8 mEq/kg body weight) to inhibit the inositol monophosphatase (IP1) activity. All mice were decapitated 4 hr after lithium injection. Labeled inositol phospholipids accounted for 16 to 23% of total labeled inositol in different regions of control mouse brain, and the percentages in the hippocampus were consistently higher than the cerebral cortex and cerebellum. In control mice, the percentages of labeled IP, after a 4-hr lithium treatment were 11.5%, 9.9%, and 3.7% for cerebral cortex, hippocampus, and cerebellum, respectively. Chronic ethanol feeding resulted in a significant (p < 0.05) decrease in the percent of labeled IP1 and inositol phospholipids, and this effect was observed in the cerebral cortex and, to a lesser extent, hippocampus but not cerebellum. When ratios of labeled IP1 were expressed against labeled inositol phospholipids as an index of the poly-PI turnover activity, significant decreases in IP/lipid ratios were observed in the cerebral cortex, but not the hippocampus or cerebellum. Although mice killed 24 + 4 hr after the last ethanol feeding would have experienced an 8-hr period of ethanol withdrawal, compared with the 16 + 4-hr group, no differences in IP/lipid ratios were observed between the two time groups. These results illustrate regional differences in the effect of chronic ethanol on inositol metabolism in the brain, but no difference in poly-PI turnover in brain due to ethanol withdrawal.  相似文献   
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