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991.
The Psychosomatic Symptom Checklist (PSC), a questionnaire assessing psychosomatic symptoms, was administered to two separate samples of college students. For Sample 1 (N=698),the questionnaire was readministered to three separate subsets at intervals of either 1 week (N=143),4 weeks (N=74),or 8 weeks (N=48).Each subset of subjects recompleted the PSC on only one of the three retest intervals. Based on the initial administration an analysis of the normative data revealed a mean total score of 23.7, suggesting a relatively low degree of psychosomatic symptoms in this group. Although total scores decreased slightly over time, test-retest correlations remained high (r>0.80, P<0.0001).Individual item correlations varied and also decreased across time; however, the majority of correlations was greater than r=0.50 throughout. Sample 2 (N=249)completed the PSC, Beck Depression Inventory (BDI), State-Trait Anxiety Inventory (STAI-X), and Rathus Assertiveness Scale (RAS), and intercorrelations were computed between these measures. This analysis revealed little overlap between the psychosomatic complaints assessed by the PSC and other commonly used measures of psychological distress. Finally, a factor analysis revealed one major factor on which all but 2 of the 17 questionnaire items loaded significantly. These results suggest that the PSC is sensitive to psychosomatic distress and remains reliable over time.This reaserch was supported in part by Grants NS-15235 and NS-16891 from NINCDS.  相似文献   
992.
Intravenous injection of t-butyl hydroperoxide rapidly killed Plasmodium vinckei in mice, and caused haemolysis. The same dose seemed harmless to unparasitized mice. Many parasites disintegrated inside circulating erythrocytes, so parasite death was not simply a passive consequence of haemolysis. Injection of desferrioxamine, which removes the traces of free iron that promote the dissociation of t-butyl hydroperoxide into radical species, prevented both parasite death and haemolysis. Lipid peroxidation, as measured by accumulation of malonyldialdehyde over 2 h in vitro, occurred in erythrocytes exposed to t-butyl hydroperoxide, and was particularly marked in erythrocytes from parasitized mice. These erythrocytes accumulated appreciable malonyldialdehyde even without exposure to t-butyl hydroperoxide. Desferrioxamine inhibited the accumulation of malonyldialdehyde, but did not prevent depletion of reduced glutathione by t-butyl hydroperoxide. This suggests that t-butyl hydroperoxide damaged parasites and erythrocytes by dissociating into radical species, rather than by decreasing intraerythrocyte anti-oxidant capacity. In earlier experiments we suggested that intraerythrocytic parasite death and haemolysis caused by alloxan were mediated by radical species, and these experiments with t-butyl hydroperoxide add weight to this interpretation. We regard both of these systems as models for macrophage-induced parasite death and host pathology in acute malaria.  相似文献   
993.
Cytogenetic studies on fetal blood cells obtained at 18–25 weeks gestation have provided information for decision making in 25 cases identified as being at high risk of having an abnormal fetus. In particular, in the 21 cases studied to consider the possibility of true mosaicism, confirmation in fetal blood was obtained in three, one of which presented as a pseudomosaic on the original amniotic fluid cell study. Fetal blood was also informative in two cases (one positive and the other negative) in which a diagnosis of the fragile X syndrome was being considered. Furthermore, when high risk pregnancies presented late in gestation (21–24 weeks), these methods allowed for a rapid cytogenetic diagnosis. The procedure has proved useful in most of these cases since the couples involved had indicated that they would probably have terminated the pregnancy without the reassurance of normal fetal lymphocyte studies. Since the technique carries a much higher risk of pregnancy loss than does amniocentesis, its use should only be considered when there are compelling indications.  相似文献   
994.
995.
Genetic mapping ofPim-1 putative oncogene to mouse chromosome 17   总被引:10,自引:0,他引:10  
Pim-1 is a putative oncogene activated in T-cell lymphomas induced by Moloney and AKR mink cell focus forming (MCF) viruses. We have determined the chromosomal localization of the Pim-1gene in mice by Southern blot analysis of DNAs obtained from a panel of mouse-Chinese hamster somatic cell hybrids. The Pim-1gene was localized on chromosome 17, a chromosome frequently aberrant in T-cell lymphomas. Two chromosomal regions, containing sequences homologous to regions within the Pim-1locus, were localized on chromosome 6 and 16.  相似文献   
996.
997.
We present two cases of a thrombus in the ascending aorta causing an acute myocardial infarction (AMI) and review the 10 other cases previously reported in the literature. This life-threatening condition appears to be more common in female smokers in their fifth decade. Suspicion should be raised in individuals at low risk for atherosclerotic disease with coronary angiographic findings not in keeping with the clinical presentation. The diagnosis may be obtained by transesophageal echocardiography, and we generally recommend surgical thrombectomy.  相似文献   
998.
C6, a Borrelia burgdorferi-derived peptide, is used as the antigen in the C6-Lyme disease diagnostic test. We assessed retrospectively whether a fourfold decrease or a decrease to a negative value in anti-C6 antibody titer is positively correlated with a positive response to treatment in a sample of culture-confirmed patients with either early localized (single erythema migrans [EM]; n = 93) or early disseminated (multiple EM; n = 27) disease. All of these patients had been treated with antibiotics and were free of disease within 6 to 12 months of follow-up. Results show that a serum specimen taken at this time was either C6 negative or had a ≥4-fold decrease in C6 antibody titer with respect to a specimen taken at baseline (or during the early convalescent period if the baseline specimen was C6 negative) for all of the multiple-EM patients (P < 0.0001) and in 89% of the single-EM patients (P < 0.0001). These results indicate that a decline in anti-C6 antibody titer coincides with effective antimicrobial therapy in patients with early localized or early disseminated Lyme borreliosis.  相似文献   
999.
Upper gastrointestinal complaints are common in Kenya. Though these have remained unchanged over the last 20 years, the pattern of upper gastrointestinal disease on endoscopic examination seems to be changing. There appears to be progressive increase in oesophagitis and cancer of the stomach. Peptic ulcer disease has remained stable while Cancer of the oesophagus is still common. The paper intends to report on endoscopic findings at the Centre for Clinical Research, Kenya Medical Research Institute (KEMRI) over the period October 1998 and May 2001. The sources of information are records made at the time of endoscopy and histology reports on biopsies taken. Seven hundred and sixty eight patients were endoscoped. The male to female ratio was 1.7:1 with mean age +/-SD of 40.8 +/-20.1 years and age range was 3 to 96 years. Majority of the patients had abnormal findings with gastritis being the most common ( 25.8%). It is concluded that gastritis is an important cause of morbidity in Kenya. Oesophagitis, mainly due to gastroesophageal reflux disease, seems to be on the increase. Gastric cancer is not as rare as previously thought and peptic ulcer disease is still common.  相似文献   
1000.
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