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排序方式: 共有1438条查询结果,搜索用时 343 毫秒
1.
我院从1973年到1991年收治股骨干骨折446例,其中227例用中西医结合的方法治疗收到了满意的疗效,现总结报告如下: 1 一般资料 227例股骨干骨折中年龄最小2岁,最大61岁。以18~40岁者发病率最高。受伤原因主要是冒顶偏帮塌落的块煤砸伤和矿车挤伤。少部分是车祸。儿童以摔伤多见。 2 治疗对于227例股骨干骨折采用闭合手法复位,夹板或纸板外固定,配合牵引。受伤初期采用重量牵引特别是斜型骨折;粉碎型骨折牵引重量是体重1/6kg。利用牵引恢复肢体轴线,减少再损伤。为尽快消肿止痛,配合应 相似文献
2.
我院自1968年至1984年共施行连续硬膜外麻醉15000人次,其中穿破硬膜12人次(0.08%)。采用硬膜外自家血充填法,防治刺破硬膜后并发头痛取得良好效果,现介绍如下。自家血液配制:以10ml注射器抽蒸溜水4ml。再抽自家血6ml,充分摇动,使红细胞溶解,避免血液凝固形成小的凝血块。 相似文献
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Cultured hippocampal slices prepared from apolipoprotein E (apoE)-deficient mice were exposed to an inhibitor of cathepsins B and L and then processed for an ultrastructural analysis of neuronal features for pyramidal cell bodies. Electron microscopy showed that the nuclei of pyramidal cells from treated hippocampal slices were more eccentrically located than those from untreated slices. In addition, increased numbers of vesicles were associated with the Golgi complex while microtubules were less frequent in the proximal dendrites. Consistent with previous studies in rats, treated apoE-deficient slices had increased numbers of lysosomes and multivesicular bodies. Finally, there were reductions in the number of synapses around the cell body, a finding similar to that found in the brains from Alzheimer's disease patients. These results provide ultrastructural data indicating that partial lysosomal dysfunction in apoE-deficient brains rapidly induces characteristic features of the aged human brain. 相似文献
5.
Bi X Gatanaga H Tanaka M Honda M Ida S Kimura S Oka S 《Journal of acquired immune deficiency syndromes (1999)》2005,38(1):1-4
The Dynabeads method showed the potential for enumerating CD4 T lymphocytes (CD4 count) in HIV-1-infected individuals. The large volume of Dynabeads required for 1 sample and complex procedure made the method expensive and not easy for use, however. To decrease the cost and simplify the procedure, we reduced the volume of the Dynabeads, added wash times, and skipped over the staining step so as to count the CD4 cells directly under an optical microscope. The CD4 count of 246 blood samples using our modified Dynabeads method (DynabeadsCD4) showed a significant correlation with that obtained by flow cytometry (FlowcytoCD4) (r = 0.91 [P < 0.0001]; slope = 1.03, intercept = -16). The sensitivity and specificity for a CD4 count less than 200 cells/microL were 79% and 94%, and for a CD4 count less than 350 cells/microL, the sensitivity and specificity were 95% and 88%, respectively. The positive and negative predictive values for a CD4 count less than 350 cells/microL were 97% and 83%, respectively. The systematic error was 8 cells/microL (95% confidence interval [CI]: 0.4-16). The cost of Dynabeads for 1 sample was less than $1.00; thus, the estimated cost per DynabeadsCD4 test is less than $3.00, including the cost of other disposable materials. Our modified method is simple, economic, and accurate enough to monitor antiretroviral therapy in resource-limited situations. 相似文献
6.
Regionally selective changes in brain lysosomes occur in the transition from young adulthood to middle age in rats 总被引:1,自引:0,他引:1
The possibility that brain aging in rats exhibits regional variations of the type found in humans was studied using lysosomal chemistry as a marker. Age-related (two vs 12months; male Sprague-Dawley) differences in cathepsin D immunostaining were pronounced in the superficial layers of entorhinal cortex and in hippocampal field CA1, but not in neocortex and field CA3. Three changes were recorded: an increase in the intraneuronal area occupied by labeled lysosomes; clumping of immunopositive material within neurons; more intense cytoplasmic staining. Western blot analyses indicated that the increases involved the active forms of cathepsin D rather than their proenzyme. Shrinkage of cathepsin-D-positive neuronal cell bodies was observed in entorhinal cortex but not in neocortical sampling zones. Age-related lysosomal changes as seen with cathepsin B immunocytochemistry were considerably more subtle than those obtained with cathepsin D antibodies. In contrast, a set of glial and/or vascular elements located in a distal dendritic field of the middle-aged hippocampus was much more immunoreactive for cathepsin B than cathepsin D. The areas exhibiting sizeable changes in the present study are reported to be particularly vulnerable to aging in humans.The results thus suggest that aspects of brain aging common to mammals help shape neurosenescence patterns in humans. 相似文献
7.
Correlation of AIB1 overexpression with advanced clinical stage of human colorectal carcinoma 总被引:7,自引:0,他引:7
AIB1, a member of the steroid receptor coactivator 1 family, has been cloned on 20q12 and is a candidate oncogene in human breast cancer. It is commonly amplified and overexpressed in several types of human cancers. In this study, we examined the expression of AIB1, as related to clinicopathologic features, in 85 human colorectal cancers (CRCs). The status of the number of AIB1 copies, p53 expression, and DNA ploidy was also analyzed. The overexpression of AIB1 was detected in 35% of CRCs. Amplification of AIB1 was observed in 10% of CRCs. In addition, the overexpression of AIB1 was observed more frequently in CRCs in later clinical stages (T3 N1 M0/T3 N0 2M1), compared with that in T3 N0 M0 stage (P < .05). These results suggest that overexpression of AIB1 might provide a selective advantage for the developmental growth and/or progression of subsets of CRCs. In addition, a significant correlation (P < .05) of overexpression of AIB1 with p53 overexpression as well as with aneuploid DNA content was observed in these CRCs. The overexpression of p53 was also correlated significantly with CRC DNA ploidy (P < .05). Furthermore, there was a substantial population of CRCs showing overexpression of both AIB1 and p53 protein and all had aneuploid DNA content; most of these were in the later clinical stage. These findings suggest a possible convergence of AIB1 with a pathway involving p53, which might induce chromosomal instability and affect the clinical phenotype of a subset of CRCs. 相似文献
8.
Onody P Bertrand F Muzeau F Bièche I Lidereau R 《Archives of pathology & laboratory medicine》2001,125(6):746-750
BACKGROUND: HER-2/neu (ERBB2) gene amplification and/or overexpression is a major event in human breast tumorigenesis. HER-2/neu gene alterations have been the most frequently assessed prognostic factors during the last 10 years in breast cancer and have recently emerged as a management decision tool and a therapeutic target. There is still controversy over the best method to determine whether a tumor is HER-2/neu positive. Because of the increasing demand for HER-2/neu gene status determination in clinical practice, we compared HER-2/neu gene alterations at the DNA level (gene amplification) and the protein level (overexpression) in a panel of patients with lymph node-negative breast cancer who had received local radiotherapy alone, with no adjuvant therapy. METHODS: We tested 100 excised lymph node-negative breast tumors, using fluorescence in situ hybridization (FISH) with a biotinylated HER-2/neu DNA probe and immunohistochemical assays (IHC) with 2 different antibodies. RESULTS: The FISH frequency of HER-2/neu gene amplification was 15%, and the IHC frequency of overexpression was 21%. CONCLUSION: Although HER-2/neu amplification by FISH and HER-2/neu overexpression by IHC correlated well in this panel of lymph node-negative breast carcinomas, there were a number of discordant cases, pointing to the important need for determining HER-2/neu alteration for the future management of HER-2/neu-based clinical applications. 相似文献
9.
Uptake and pathogenic effects of amyloid beta peptide 1-42 are enhanced by integrin antagonists and blocked by NMDA receptor antagonists 总被引:4,自引:0,他引:4
Many synapses contain two types of receptors - integrins and N-methyl-D-aspartate (NMDA) receptors - that have been implicated in peptide internalization. The present studies tested if either class is involved in the uptake of the 42-residue form of amyloid beta peptide (Abeta1-42), an event hypothesized to be of importance in the development of Alzheimer's disease. Cultured hippocampal slices were exposed to Abeta1-42 for 6 days in the presence or absence of soluble Gly-Arg-Gly-Asp-Ser-Pro, a peptide antagonist of Arg-Gly-Asp (RGD)-binding integrins, or the disintegrin echistatin. Abeta uptake, as assessed with immunocytochemistry, occurred in 42% of the slices incubated with Abeta peptide alone but in more than 80% of the slices co-treated with integrin antagonists. Uptake was also found in a broader range of hippocampal subfields in RGD-treated slices. Increased sequestration was accompanied by two characteristics of early stage Alzheimer's disease: elevated concentrations of cathepsin D immunoreactivity and activation of microglia. The selective NMDA receptor antagonist D-(-)-2-amino-5-phosphonovalerate completely blocked internalization of Abeta, up-regulation of cathepsin D, and activation of microglia. Our results identify two classes of receptors that cooperatively regulate the internalization of Abeta1-42 and support the hypothesis that characteristic pathologies of Alzheimer's disease occur once critical intraneuronal Abeta concentrations are reached. 相似文献
10.