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To determine if impaired energy metabolism might contribute to some aspects of Alzheimer disease (AD), including the vulnerability of the CA1 region of the hippocampal formation and the altered cytoskeleton evident in neurofibrillary tangles, we examined the effects of metabolic poisons on neuronal damage and cytoskeletal disruption in the hippocampal formation. Intrahippocampal injection of 3-nitropropionic acid (3-NP) and malonic acid resulted in neuronal death, particularly in CA1. Cytoskeletal disruption included loss of dendritic MAP2, but sparing of axonal τ. MK-801 (a noncompetitive NMDA receptor antagonist) did not atenuate the lesions produced by intrahippocampal injection of malonate. MK-801, however, was effective against intrastriatal malonate. Acute systemic 3-NP resulted in neuronal damage and cytoskeletal disruption in the CA1 region of the hippocampal formation, including an extensive loss of MAP2 immuno-reactivity, but sparing of τ. The neuronal loss in CA1 was delayed as compared to striatum. Chronic intraventricular infusion of 3-NP produced a different pattern of neuronal damage. Loss of τ-1 immuno-reactivity was observed in CA3 and CA1 s. oriens, whereas MAP2 immunostaining was preserved. These results demonstrate that chronic and acute administration of metabolic inhibitors produce distinct patterns of neuronal damage and cytoskeletal disruption. The results further suggest a differential involvement of the NMDA receptor in malonate-induced neuronal damage in striatum as compared to the hippocampus. The pattern of neuronal damage and cytoskeletal disruption observed following acute metabolic impairment resembled some aspects of neurofibrillary pathology in AD, but did not result in τ hyperphosphorylation.  相似文献   
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宫腹腔镜联合手术诊治不孕症150例分析   总被引:14,自引:0,他引:14  
目的:探讨宫腹腔镜联合手术在诊治不孕症中的应用。方法:对150例不孕症患者行宫腹腔镜联合手术,对不孕症病因进行诊断,同时行治疗。结果:盆腔粘连和输卵管阻塞是不孕症的主要原因。子宫内膜息肉和正常盆腔占次要比例。子宫内膜异位症和多囊卵巢也是主要病因。150例同时行宫腹腔镜输卵管通液和各种疾病的治疗。联合手术后妊娠率为48.8%。结论:腹腔镜联合手术,在一次麻醉下,可以对不孕的原因全面评价和明确诊断,在诊断同时进行治疗,对不孕症的诊断和治疗有重大的意义,值得推广。  相似文献   
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Felty's syndrome (FS), the association of rheumatoid arthritis (RA) and idiopathic neutropenia, remains an unexplained phenomenon. HLA-DR4 is found in over 90% of cases. Patients with FS may have a T cell lymphocytosis of CD3+CD8+CD57+ large granular lymphocytes (LGL syndrome). In this study of 47 patients with FS, 19% had clear evidence for LGL expansions, while in total 42% had variable evidence for the LGL syndrome using currently available techniques. Of these T cell expansions, 76% were clonal, as demonstrated by Southern blotting and analysis with T cell receptor (TCR) beta chain constant region probes. This technique may fail to detect clonal populations in some patients. Cytofluorographic analysis using antibodies specific for TCR V beta chains identified patients with clonal LGL expansions with results comparable to those obtained with Southern blotting. No evidence for shared V beta usage among expansions from different patients was seen. The role of LGL in RA and FS is currently unclear, but this technique offers a practical and accessible means of identifying patients with LGL expansions, as a starting point for further investigation.  相似文献   
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R O Barnard  J F Geddes 《Cancer》1987,60(7):1519-1531
A series of 241 gliomas (astrocytomas, oligodendrogliomas, glioblastomas, and subependymal giant-cell astrocytomas) was studied. This represents all the gliomas examined post mortem over 25 years at one hospital. Two hundred and one cases (85%) were apparently solitary tumors; of the 40 cases with multiple tumor foci, 23 (9.5%) were true multicentric gliomas. After excluding cases in which there was concomitant disease (neurofibromatosis, tuberose sclerosis, or multiple sclerosis), 18 cases of multicentric tumor (7.5%) remained. Multicentric tumors with different histologic appearances accounted for 2.9% of the series. Celloidin-embedded whole brain sections proved invaluable for the detection of microscopic neoplastic foci and unsuspected diffuse spread. The estimated incidence of multiplicity in gliomas is higher than in most series, but the findings suggest that detection of multifocal neoplastic change in these tumors is directly related to the extent to which the brain is sampled, and that figures obtained in this study may well underestimate the true incidence.  相似文献   
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A case of life-threatening respiratory distress during a Caesarean section under spinal anaesthesia is reported. Possible causes of the event including anaphylactoid reactions and the methods of their diagnosis are discussed. The most likely cause of the episode was felt to be an anaphylactoid reaction to Syntocinon.  相似文献   
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Amino acid concentrations were measured in the cord blood serum from neonates following 23-41 weeks gestation. These values were then correlated with the gestational age of the newborns. A significant (p less than 0.05) correlation was observed with the concentrations of six amino acids, and five of these correlations were negative. The significance of these normative data are discussed and compared with currently available cord blood aminogram data.  相似文献   
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