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81.
HIV-related encephalitis presenting as convulsant disease   总被引:1,自引:0,他引:1  
Because of the growing incidence of neurological disorders in HIV-infected patients, an early detection of the disease seems to be of paramount importance, especially in asymptomatic subjects. By using electroencephalography coupled with computerized spectral analysis and "mapping" (EEG-CSA), paroxysmal sharp activity was detected in 26 patients belonging to different stages of HIV infection. Seven of them (27%) were also symptomatic, (table; see text) showing signs of convulsant disease. The presence of focal or generalized paroxysmal activity, often associated with seizures, might suggest an early localization of HIV in cortical structures.  相似文献   
82.
BACKGROUND AND PURPOSE: Long-term daily aspirin is of benefit in the years after ischemic stroke, and 2 large randomized trials (the Chinese Acute Stroke Trial [CAST] and the International Stroke Trial [IST]), with 20 000 patients in each, have shown that starting daily aspirin promptly in patients with suspected acute ischemic stroke also reduces the immediate risk of further stroke or death in hospital and the overall risk of death or dependency. However, some uncertainty remains about the effects of early aspirin in particular categories of patient with acute stroke. METHODS: To assess the balance of benefits and risks of aspirin in particular categories of patient with acute stroke (eg, the elderly, those without a CT scan, or those with atrial fibrillation), a prospectively planned meta-analysis is presented of the data from 40 000 individual patients from both trials on events that occurred in the hospital during the scheduled treatment period (4 weeks in CAST, 2 weeks in IST), with 10 characteristics used to define 28 subgroups. This represents 99% of the worldwide evidence from randomized trials. RESULTS: There was a highly significant reduction of 7 per 1000 (SD 1) in recurrent ischemic stroke (320 [1.6%] aspirin versus 457 [2. 3%] control, 2P<0.000001) and a less clearly significant reduction of 4 (SD 2) per 1000 in death without further stroke (5.0% versus 5. 4%, 2P=0.05). Against these benefits, there was an increase of 2 (SD 1) per 1000 in hemorrhagic stroke or hemorrhagic transformation of the original infarct (1.0% versus 0.8%, 2P=0.07) and no apparent effect on further stroke of unknown cause (0.9% versus 0.9%). In total, therefore, there was a net decrease of 9 (SD 3) per 1000 in the overall risk of further stroke or death in hospital (8.2% versus 9.1%, 2P=0.001). For the reduction of one third in recurrent ischemic stroke, subgroup-specific analyses found no significant heterogeneity of the proportional benefit of aspirin (chi(2)(18)=20. 9, NS), even though the overall treatment effect (chi(2)(1)=24.8, 2P<0.000001) was sufficiently large for such subgroup analyses to be statistically informative. The absolute risk among control patients was similar in all 28 subgroups, so the absolute reduction of approximately 7 per 1000 in recurrent ischemic stroke does not differ substantially with respect to age, sex, level of consciousness, atrial fibrillation, CT findings, blood pressure, stroke subtype, or concomitant heparin use. There was no good evidence that the apparent decrease of approximately 4 per 1000 in death without further stroke was reversed in any subgroup or that in any subgroup the increase in hemorrhagic stroke was much larger than the overall average of approximately 2 per 1000. Finally, there was no significant heterogeneity between the reductions in the composite outcome of any further stroke or death (chi(2)(18)=16.5, NS). Among the 9000 patients (22%) randomized without a prior CT scan, aspirin appeared to be of net benefit with no unusual excess of hemorrhagic stroke; moreover, even among the 800 (2%) who had inadvertently been randomized after a hemorrhagic stroke, there was no evidence of net hazard (further stroke or death, 63 aspirin versus 67 control). CONCLUSIONS: Early aspirin is of benefit for a wide range of patients, and its prompt use should be routinely considered for all patients with suspected acute ischemic stroke, mainly to reduce the risk of early recurrence.  相似文献   
83.
目的:观察CBN对脑缺血再灌注小鼠的线粒体损伤的影响。方法:分离提纯脑缺血再灌注小鼠脑的线粒体。用分光光度法检测线粒体的膜肿胀度,用激光拉曼光谱检测脑线粒体的生物大分子的变化。结果:小鼠脑缺血再灌注后。其线粒体出现膜肿胀,CBN50、100mg/kg iv对此有明显的抑制作用。各组脑线粒体的Raman和IR光谱基本一致。CBN组与假手术组比较接近。模型组只是在量上有一些差异。结论:CBN对脑缺血再灌注小鼠的线粒体损伤的有一定的保护作用。  相似文献   
84.
BACKGROUND AND PURPOSE: Anti-Helicobacter pylori triple therapy is effective for healing duodenal ulcer (DU) diseases and reducing disease recurrence. However, multifocal duodenal erosions or shallow ulcers may develop after triple therapy. The purpose of this study was to investigate the incidence and outcome of duodenal erosions that developed after triple therapy. METHODS: A total of 106 Taiwanese with active DU and with H. pylori infection were enrolled in this study. All patients received anti-H. pylori triple therapy (i.e., 2 weeks of antimicrobial agents combined with treatment for 4 to 6 weeks with acid suppression agents). Follow-up endoscopy was performed immediately after stopping treatment. The incidence of multifocal erosions or shallow ulcers over the bulb and/or second portion of the duodenum was studied. Additional acid suppression agent was given for 4 weeks whenever duodenal erosions or shallow ulcers were found. RESULTS: Out of 106 patients, 11 (10.4%) were found to have multifocal duodenal erosions and/or shallow ulcers on the duodenal bulb and/or second portion of the duodenum at the end of treatment. Ten of the 11 patients with newly developed erosions had healed DU in the S1 or S2 stage, and all 11 had successful H. pylori eradication. The duodenal erosions and/or shallow ulcers of these 11 patients were healed after an additional 4 weeks of histamine-2-receptor antagonist therapy. CONCLUSIONS: Multifocal duodenal erosions and/or shallow ulcers were noted in around 10% of Taiwanese DU patients who received anti-H. pylori triple therapy. An additional 4 weeks therapy with acid suppression agents healed these lesions.  相似文献   
85.
In the humoral immune response to an invasion of foreign antigens, B cells differentiate into low-affinity antibody-forming cells (AFCs) that mainly secrete IgM or, through germinal center (GC) formation, into high-affinity AFCs that secrete IgG-class antibodies with a higher affinity for the antigen. Previous studies have established the suppressive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on low-affinity antibody responses to antigens. However, whether and how TCDD affects the high-affinity antibody response to antigens has not yet been clarified. In this paper we investigate the effects of TCDD on GC formation, high-affinity AFC generation, and high-affinity antibody production in the primary humoral immune response. C57BL/6 mice were orally administered 0 or 20 microg/kg of TCDD and subsequently immunized with alum-precipitated ovalbumin (OVA) on day 0. Then the GC formation in the spleen and OVA-specific antibodies in the plasma, was evaluated until day 14 postimmunization. TCDD exposure reduced the production of OVA-specific IgG1 on days 10 and 14. GC formation in the spleen was also suppressed by TCDD exposure, and the suppression persisted from day 7 until day 14. In TCDD-administered mice, on day 7, cellular proliferation in the GCs was significantly suppressed, although apoptosis was not markedly affected. In order to measure high-affinity antibody and high-affinity AFCs, the mice were administered TCDD followed by immunization with alum-precipitated (4-hydroxy-3-nitrophenyl) acetyl linked to chicken gamma-globulin (NP-CG). The frequency of high-affinity NP-specific AFCs that bind to low-haptenated antigen was clearly shown to be reduced in the spleen on days 10 and 14. Furthermore, the high-affinity anti-NP IgG1 levels on days 10 and 14 postimmunization were significantly reduced by TCDD exposure. Taken together, the results of this paper demonstrate that TCDD exposure inhibits the generation of high-affinity AFCs and high-affinity antibody production during the primary humoral immune response and suggest that these alterations were caused by the suppression of antigen-responding B-cell proliferation induced by TCDD during GC formation.  相似文献   
86.
The SH2 domain-containing inositol 5'-phosphatase (SHIP) is crucial in hematopoietic development. To evaluate the possible tumor suppressor role of the SHIP gene in myeloid leukemogenesis, we examined primary leukemia cells from 30 acute myeloid leukemia (AML) patients, together with eight myeloid leukemia cell lines. A somatic mutation at codon 684, replacing Val with Glu, was detected in one patient, lying within the signature motif 2, which is the phosphatase active site. The results of an in vitro inositol 5'-phosphatase assay revealed that the mutation reduced catalytic activity of SHIP. Leukemia cells with the mutation showed enhanced Akt phosphorylation following IL-3 stimulation. K562 cells transfected with the mutated SHIP-V684E cDNA showed a growth advantage even at lower serum concentrations and resistance to apoptosis induced by serum deprivation and exposure to etoposide. These results suggest a possible role of the mutated SHIP gene in the development of acute leukemia and chemotherapy resistance through the deregulation of the phosphatidylinositol-3,4,5-triphosphate (PI(3,4,5)P3)/Akt signaling pathway. This is the first report of a mutation in the SHIP gene in any given human cancer, and indicates the need for more attention to be paid to this gene with respect to cancer pathogenesis.  相似文献   
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89.
为确立一种原发喉室的跨声门癌,选择肿瘤主体以喉室为中心经全喉切除手术的标本50例,火棉胶包埋,连续切片观察。结果发现①跨声门癌的肿瘤原发部位在喉室,50例中有T23例。②肿瘤以深层浸润为主占90%(45/50),易侵及声门旁间隙(82%,41/50)和甲状软骨(64%,32/50),临床分期与病理分期不符达48%(24/50)。结论:原发喉室的跨声门癌是声门上型癌的一种特殊类型。  相似文献   
90.
HPLC测定佛手增乳膏中阿魏酸的含量   总被引:4,自引:0,他引:4  
潘锡强  刘宇翔 《中成药》1998,20(11):12-13
佛手增乳膏经乙醚,2%碳酸钠液萃取后,用HPLC测定阿魏酸的含量。方法简便,快速,准确。  相似文献   
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