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61.
Antibodies to an intercellular substance of epidermis and other stratified squamous epithelia demonstrable by immunofluorescent staining have been reported to occur in the sera of patients with pemphigus vulgaris. Using sera of patients with bullous pemphigoid, antibodies to a component of the basement zone of skin had been found by the same technique. In the present study these observations have been confirmed and extended. In addition to the above mentioned immunofluorescent staining reactions, another type of antibody directed to a cytoplasmic or perinuclear component of epidermal cells was found in a variety of pathologic sera. This observation points to the need for differentiating other skin-reactive antibodies from those found only in pemphigus. Guinea-pig lip sections appeared to be satisfactory for these studies. Mixed immunofluorescence was found to yield staining reactions identical to those observed by the indirect staining method, and gave titres the same as or lower than those obtained by the indirect staining procedure. Using the indirect method with guinea-pig lip sections it was found that eight of ten sera of patients with pemphigus contained intercellular antibodies while 102 control sera failed to yield reactions of this type. The titres of antibodies appeared to be proportional to the severity of the disease process. Sera of two out of three patients suffering from bullous pemphigoid yielded immunofluorescence staining of the basement zone while 109 controls were negative for this antibody.  相似文献   
62.
According to the reformulated learned helplessness model of depression, causal attributions are an important mediator of the effects on mood of positive and negative experiences. Adaptive attributions for negative events are assumed to be external, unstable, and specific. In the present study, subjects exposed to one of two attribution training procedures or a control condition made attributions for hypothetical events under neutral and adaptive instructional sets. Attributions were rated by subjects and coders blind to the purpose of the study. Results indicated that subjects' views of adaptive causal attributions were congruent with predictions from the learned helplessness model. The ratings of the objective coders indicated that subjects' attributions really did change in response to the adaptive instructions in the predicted direction. Implications of these results for the reformulated learned helplessness model and depression therapies that include an attribution retraining component are discussed.The authors would like to thank Dan Russell for his very helpful comments on earlier drafts of this paper.  相似文献   
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Serotonergic mechanisms of cocaine effects in humans   总被引:1,自引:0,他引:1  
The objective of this study was to investigate the role of serotonin (5-HT) in mediating the effects of cocaine in humans. To accomplish this, 12 subjects each participated in two randomized, double-blind test sessions separated by 1 week. In one session, subjects underwent acute depletion of the 5-HT amino acid precursor tryptophan (TRP), followed by a test dose of intranasal cocaine. In the other session, the cocaine test dose was preceded by sham depletion. Subject ratings of cocaine high were significantly lower following active TRP depletion than after the sham procedure. Subjects also showed an earlier but less sustained rise in self-rated nervousness during active TRP depletion. These findings are consistent with the hypothesis that 5-HT may be involved in mediating the euphorigenic and modulating the anxiogenic effects of cocaine in humans, either directly or through actions on other (e.g., dopaminergic) systems.  相似文献   
67.
Cervical secretory immunoglobulin A in adolescent girls.   总被引:5,自引:0,他引:5  
PURPOSE: To determine whether there are differences in levels of cervical secretory immunoglobulin A (sIgA) between adolescent girls in the secretory and proliferative phases of their menstrual cycle. METHODS: Sexually active adolescent girls (n = 117) at health maintenance organization (HMO) based adolescent medical clinic were recruited into the study. In addition to demographic and clinical data, cervical specimens were collected for sIgA measurement and gonorrhea culture, urine for chlamydia ligase chain reaction, and blood for progesterone levels. Subjects were classified as being in the proliferative phase or secretory phase of the menstrual cycle on the basis of their progesterone levels. RESULTS: The mean age of the subjects was 17.2 years old. There was no difference in the sIgA levels between those in the proliferative phase of their cycle (n = 45; mean sIgA level, 0.0055 mg/mL) and those in the secretory phase (n = 40; mean sIgA level, 0.0032 mg/mL) (p > .10). CONCLUSIONS: The secretory phase of the menstrual cycle does not appear to be associated with higher levels of sIgA in adolescent girls. These results suggest that adolescents with anovulatory cycles, i.e., those who lack a secretory phase, may not be at increased risk for genital tract infections such as chlamydia or gonorrhea.  相似文献   
68.
A case-control study of 19 patients with HIV-associated mania and 57 HIV-seropositive control patients matched by CD4 cell count, age, and year of treatment was undertaken to investigate associations with risk factors for human immunodeficiency virus (HIV) infection, treatment, and disease. There was no significant difference between groups for HIV exposure category, baseline health status, or drugs other than antiretrovirals. Zidovudine therapy provided a significant protective effect against the development of mania, whether administered at or prior to diagnosis of mania. In a 3-year follow-up study, incident AIDS dementia was significantly more common in patients with mania, despite no apparent difference in survival between cases and controls. These findings strengthen the evidence of an etiological association of HIV neuropathology with AIDS mania by demonstrating a protective effect of an antiretroviral agent able to penetrate the central nervous system.  相似文献   
69.
Summary A flow-throught system was used to study the cellular pharmacokinetics of 5-fluorouracil (5-FU) in four human cell lines (squamous-cell carcinoma HEp-2, colon carcinoma WiDr, hepatoma Hep G2, and breast carcinoma MCF-7) as well as in the rat hepatoma H35 cell line and in freshly isolated rat hepatocytes. The system made it possible to restrict the decrease in the concentration of 5-FU in the medium, to keep the volume in which the metabolites accumulated relatively small, and to study the dynamics of a response during and after a change in the composition of the eluent. Clearance of 5-FU from the eluent was achieved predominantly (>95%) by its catabolism to dihydrofluorouracil in the tumor cell lines and to 2-fluoro--alanine in the hepatocytes. Not only rat hepatocytes but also HEp-2 cells showed relatively high clearance values. A concentration-dependent 5-FU elimination was observed, indicating saturation of 5-FU elimination according to Michaelis-Menten kinetics (Km 14–22 M). The maximal velocity (Vmax) values ranged from 0.025 to 0.13 nmol 5-FU/106 cells per minute. For HEp-2 cells, high-concentration pulse injections of 5-FU, thymine, uridine, or uracil immediately led to a reduction in 5-FU conversion, followed by recovery within 5 min. The flow-through system proved to be adequate for the study of the non-linear pharmacokinetics of 5-FU in different intact cells and for the comparison of various manipulations of these pharmacokinetics.Abbreviations 5-FU 5-fluorouracil - FUR 5-fluorouridine - F-DHU dihydrofluorouracil - F--ala 2-fluoro--alanine - F-UPA -fluoroureidopropionic acid - HEPES 4-(2-hydroethyl)-1-piperazine-ethane sulfonic acid - MEM modified minimal essential medium - HBSS Hanks' balanced salt solution - HPLC high-performance liquid chromatography Supported by grant IKA 87-16 from the Netherlands Cancer Foundation. One author (G. J. P.) is the recipient of a senior research fellowship from the Royal Netherlands Academy of Arts and Sciences (KNAW)  相似文献   
70.
PURPOSE: The purpose of this research was to evaluate toxicity, response, and changes in oxygenation (pO(2)) in patients with locally advanced breast cancer (LABC) treated with concurrent taxol, hyperthermia (HT), and radiation therapy (RT) followed by mastectomy. EXPERIMENTAL DESIGN: Eighteen patients with LABC were enrolled from October 1995 through February 1999. Treatment consisted of taxol (175 mg/m(2)) given every 3 weeks for three cycles. Radiation therapy included the breast and regional nodes with a dose of 50 Gy, followed by a boost to 60-65 Gy for those not undergoing surgery. Mastectomy was performed for patients deemed resectable after this neoadjuvant program. HT was administered twice per week. Oxygenation was measured before the first HT treatment and 24 h after the first HT treatment. RESULTS: Fifteen of 18 patients responded, 6 with a clinical complete response, 9 with a partial clinical response, and 3 nonresponders. Thirteen underwent mastectomy with 3 pathological complete responses. Tumor hypoxia was present in 8 of 13 patients (pO(2) = 4.7 +/- 1.2 mmHg). Five patients had well-oxygenated tumors (pO(2) = 27.6 +/- 7.8 mmHg). Patients with well-oxygenated tumors before treatment as well as those with significant reoxygenation had a favorable clinical response. Tumor reoxygenation appeared to be temperature dependent and associated with the lower thermal doses. CONCLUSIONS: This novel therapeutic program resulted in a high response rate in patients with LABC. Hyperthermia may offer a strategy for improving tumor reoxygenation with consequent treatment response. However, the effect of hyperthermia on tumor reoxygenation appears to depend on thermal dose and requires additional investigation.  相似文献   
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