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1.
We have previously shown that sera from patients with Alzheimer’s disease (AD) contain antibodies to the cell bodies (perikarya; PK) of purely cholinergicTorpedo neurons, and that repeated immunization of rats with this neuronal preparation for over a year induces learning and memory impairments. In the present study, we examined the brain morphology of cholinergic PK immunized rats relative to controls. Immunohistochemical studies of the brains of these rats revealed the accumulation of IgG in specific areas, such as, the hippocampus. Parallel histochemical studies demonstrated significant changes in the hippocampus, and in white matter areas. They included large vacuoles and necrotic nuclei in the granular layer of the dentate gyrus, tangle-like appearance in some pyramidal neurons of the hippocampus, and vacuolar degeneration accompanied by oligodendroglia hypertrophy in white matter tracts, such as, the corpus callosum and fimbria. In contrast, immunization withTorpedo cholinergic nerve terminals, that has no cognitive effects on the rat, also did not induce brain morphological changes. These findings suggest that the learning and memory deficits induced by immunizing rats with cholinergic PK are related to the observed brain morphological changes, and support the hypothesis that the antibodies to cholinergic neurons found in the sera of AD patients may play a role in neuronal degeneration in this disease.  相似文献   
2.
Dichloromethane extracts of the root bark and stem bark of Kigelia pinnata collected from Zimbabwe exhibited antitrypanosomal activity against Trypanosoma brucei brucei in vitro. Activity-guided fractionation led to the isolation of four naphthoquinones from both the root and stem bark of the plant. The compounds were identified as 2-(1-hydroxyethyl)-naphtho[2,3-b]furan-4,9-quinone (1), isopinnatal (2), kigelinol (3), and isokigelinol (4). Subsequently, the compounds were assessed for antitrypanosomal activity against T. brucei brucei and T. brucei rhodesiense bloodstream form trypomastigotes in vitro. Compound 1 with a furanonaphthoquinone structure was found to possess pronounced activity against both parasites with IC50 values of 0.12 and 0.045 microM, respectively, although it was less active than the standard drug pentamidine. Compounds 2, 3, and 4 also exhibited activity against the parasites, although to a lesser extent. The activities of the compounds were further assessed by comparison with the cytotoxic activities obtained against KB cell lines.  相似文献   
3.
BACKGROUND: The aim of this study was to compare the histomorphologic appearance of atherosclerosis in amputated legs of diabetic and non-diabetic patients. METHODS: Twenty-eight legs amputated below the knee for chronic ischaemia were studied. Fourteen legs were amputated in patients with diabetes (10 Type II, 4 nonclassified) and 14 in non-diabetics. The mean age of patients at the time of the amputation was 63.3 years in diabetics and 63.9 years in non-diabetics. Samples were taken from the main arteries at the following levels: the midleg, 5 cm above the ankle, 3 cm below the ankle and 10 cm below the ankle. Cross-sections of the arteries were examined with light microscopy and the severity of the occlusive disease determined using morphometric analysis. Medial calcification and chronic inflammation were assessed semiquantitatively. RESULTS: Arteries at 5 cm above the ankle were more severely stenotic in diabetics than in non-diabetics (p<0.05). In both diabetics and non-diabetics the posterior tibial and plantar arteries appeared to be the most stenotic. Medial calcification tended to be more prominent in diabetics than in non-diabetics. Chronic inflammation in the arterial wall occurred at the same degree in diabetics and non-diabetics. In non-diabetics chronic inflammation was more severe in the posterior tibial and plantar arteries than in the anterior tibial and dorsalis pedis arteries (p<0.04). Chronic arterial inflammation correlated with the severity of chronic arterial occlusive disease (p<0.0002). CONCLUSIONS: In diabetics occlusive disease in amputated legs is more severe in arteries above the ankle than in non-diabetics. However, no difference was demonstrated in this series in arteries of the ankle and foot. Diabetics are likely to have more medial calcification in the arteries than non-diabetics. Chronic inflammation in the arterial wall is associated with more severe stenosis.  相似文献   
4.
The case described is of a 7-year-old boy with recurrent long-segment left ventricular outflow tract obstruction. Due to previous pulmonary artery band stenosis and subsequent repair with a prosthetic patch, the pulmonary root was not intact. In this complicated Ross-Konno operation, the prosthetic patch was replaced with autologous tissue and the repaired pulmonary root was used successfully as an autograft.  相似文献   
5.
6.
Chronic dislocation is considered a rare complication after total hip arthroplasty. We have treated a patient with a complication related to chronic dislocation—protrusion of the prosthetic femoral head through the skin. This 86-year-old bedridden patient with a known dislocated total hip arthroplasty presented with fever and protrusion of an artificial femoral head after 2 months of a nonhealing pressure sore. The care of this patient was partial removal of the prosthetic components and intravenous antibiotics. Chronic dislocation is rarely reported, yet it may cause severe complications in debilitated and demented patients. Special attention should be warranted to these patients as they might benefit from earlier surgical treatment.  相似文献   
7.
The purpose of this study was to determine patients' survival after undergoing an early or delayed operation. We retrospectively assessed 1849 files of patients operated for proximal femoral fracture, divided into two diagnostic groups: intracapsular (n = 640) and extracapsular (n = 1209). 1163 (63%) were treated within 48 h from hospital admission and 686 (37%) were treated > 48 h afterwards. Delayed operation in patients with intracapsular fractures was associated with a 1.8-fold excess risk for 1-year mortality (HR = 1.83, P = 0.008), while no effect was observed for patients with extracapsular fractures. Males had a higher HR for mortality in both diagnostic groups. Early surgical intervention is beneficial for intra-capsular femoral fractures; male gender and a high ASA score are associated with an increased mortality hazard risk.  相似文献   
8.
OBJECTIVE: The objective of this study was to retrospectively assess whether there was increased morbidity associated with the addition of selective pelvic and periaortic lymphadenectomy to hysterectomy in patients with endometrial carcinoma. STUDY DESIGN: From 1977 through 1988, 196 patients undergoing selective pelvic and periaortic lymphadenectomy plus hysterectomy were compared with 104 patients who underwent hysterectomy alone for endometrial adenocarcinoma. RESULTS: Only after adjusting for covariates was selective pelvic and periaortic lymphadenectomy associated with a higher estimated blood loss, which increased linearly with weight and was higher for black than for white women. The transfusion rate was similar for the two groups (selective pelvic and periaortic lymphadenectomy 6%, hysterectomy 10%). The mean blood loss was significantly different among the four gynecologic oncology surgeons (range 343 to 652 ml). The operating time primarily depended on patient weight and race, surgeon, and estimated blood loss. Postoperative hospital stay increased significantly with age, surgeon, wound infections, thrombotic events, and serious complications. Selective pelvic and periaortic lymphadenectomy had no effect on wound infections, which were directly related to operating time. Seventy-five (38%) of the selective pelvic and periaortic lymphadenectomy group and 19 (18%) of the hysterectomy group (p < 0.01) received whole-pelvic radiation with no difference in bowel complications (selective pelvic and periaortic lymphadenectomy 2/75, hysterectomy 1/19). The risk of serious complications was associated only with increasing age. CONCLUSION: Selective pelvic and periaortic lymphadenectomy in patients with endometrial carcinoma does not significantly add to morbidity from hysterectomy, which is related primarily to other factors such as patient weight, age, and race; operating time; and surgeon.  相似文献   
9.
A prospective study was conducted to test the hypothesis that the absence of an intrauterine gestational sac when the serum level of human chorionic gonadotropin (hCG) is above 6500 mIU/mL is indicative of ectopic pregnancy. A total of 383 patients who were clinically suspected to have ectopic pregnancies had pelvic ultrasound examinations with serum hCG determinations on the day of the scan. There were 217 (57%) intrauterine gestations, 104 (27%) ectopic pregnancies, and 62 (16%) spontaneous abortions. Forty-one percent of patients had an hCG level above 6500 mIU/mL. The absence of an intrauterine gestational sac at an hCG concentration above this level had a sensitivity of 100%, a specificity of 96%, a positive predictive value of 86%, a negative predictive value of 100%, and was 98% efficient, based on a 19.4% prevalence of ectopic pregnancies among this group.  相似文献   
10.
The half-life of hCG was measured retrospectively in paired blood samples from 108 pregnancies with falling hCG levels. hCG levels fell significantly more slowly in women who had an ectopic pregnancy (41 cases) than in women who had spontaneous abortions (67 cases). When the hCG half-life was greater than or equal to 7 days, 86% of cases had ectopic pregnancies, a third of which had ruptured. By contrast, when the hCG half-life was less than 1.4 days, only 7.6% (2/26) of cases had an ectopic pregnancy (both of which were unruptured), and villi were identified in only 10% of curettage specimens from (presumed) cases of spontaneous abortion. When the half-life of hCG was between 1.4 and 6.9 days, 34% of the cases had ectopic pregnancies, 14% of which had ruptured: chorionic villi were recovered from 76% of the women who had a curettage, and failure to detect villi was more than 80% predictive of an ectopic pregnancy.  相似文献   
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