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Milieu relationships provide the critical background presence to staff's attempts to motivate, regulate, and teach patients how to cope with stress. Forging a connection with hospitalized children and adolescents demands attention to how they respond to adults and engage with staff around milieu expectations. Assessment guides that deal with these issues are presented. Important aspects of children's relatedness are presented in the context of their working models of adults and the influence of these representations on their response to staff. Coping skills are explained with particular emphasis on behavioral coping strategies. Tied to the assessment process are interventions that emphasize staff's role in helping patients manage strong affects and avoid the use of nonproductive behavior regulation strategies.  相似文献   
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Purpose: Increasingly, evidence has shown that human papillomavirus (HPV) plays a role in the induction of certain carcinomas. The presence of HPV sequences in 56 previously untreated oral and pharyngolaryngeal carcinomas was examined by the polymerase chain reaction (PCR).Materials and Methods: After DNA extraction, samples underwent 40 replication cycles with specific oligonucleotide primers corresponding to sequences from the E6 open-reading frame of HPV-6b, HPV-16, and HPV-18. To determine the E6 genomic integration, positive samples were processed with specific primers for the corresponding HPV L1 genes. Genomic HPV DNA cloned into PBR 322 was used as positive control.Results: HPV E6 DNA of the 6b and 16 types was detected in 14 patients (25%). The L1 gene was not present.Conclusion: Detected HPV E6 DNA might be integrated into the cell genome in the positive cases as indicated by the absence of the L1 gene-coding for the viral capside. Histological and clinical parameters, such as tumor location, degree of differentiation, stage, recurrence, and survival rates, were unrelated to the presence of HPV.  相似文献   
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Kaposi's sarcoma tumor cells preferentially express Bcl-xL.   总被引:10,自引:0,他引:10       下载免费PDF全文
Several recently identified proteins such as Bcl-2 and Bcl-x have been found to regulate programmed cell death (i.e., apoptosis). In this report, we examined the levels of expression of proteins that can either prevent apoptosis (i.e., Bcl-2 or the long form of Bcl-x, designated Bcl-x1) or promote apoptosis (i.e., Bax or the short form of Bcl-x, designated Bcl-xs) in proliferating benign and malignant endothelial cells (ECs). In normal skin with quiescent ECs, no detection by immunohistochemical staining was observed for Bcl-xL, Bcl-xs, or Bcl-2. However, in diseased skin samples that feature a prominent angiogenic response such as in psoriasis or pyogenic granulomas, the proliferating ECs markedly overexpressed Bcl-xL, with little to no Bcl-2. In an acquired-immune-deficiency-syndrome-related neoplasm, Kaposi's sarcoma, the spindle-shaped tumor cells also overexpressed Bcl-xL compared with Bcl-2. These in vivo studies were extended in vitro using cultured ECs and Kaposi's sarcoma tumor cells that were examined by flow cytometry and immunoblot analysis. Both cultured ECs and Kaposi's sarcoma tumor cells express significantly higher levels of Bcl-xL than Bcl-2. Such overexpression of cell survival gene products may contribute to prolonging the longevity of EC-derived cells in several different benign and neoplastic skin disorders that are characterized by a prominent angiogenic tissue response.  相似文献   
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OBJECTIVE: To compare the clinical efficacy and safety of trimethoprim-sulfamethoxazole (TMP-SMX) with pentamidine in the therapy of Pneumocystis carinii pneumonia (PCP) in patients with AIDS. PATIENTS, PARTICIPANTS: TMP-SMX (TMP, 20 mg/kg/day plus SMX, 100 mg/kg/day) was compared with pentamidine (4 mg/kg/day), both administered intravenously for 21 days in a prospective randomized treatment trial of 163 patients diagnosed with PCP between November 1984 and May 1988. RESULTS: Ninety-two evaluable patients received TMP-SMX as initial therapy; 68 received pentamidine. Failure to complete therapy was common. Of those receiving TMP-SMX, 39 (42%) required change in therapy because of failure to respond, and an additional 31 (34%) because of drug toxicity. This compared with 27 (40%; P = 0.733) and 17 (25%; P = 0.235), respectively, in the pentamidine-treated group. The overall survival rates were similar in the two groups, 62 out of 92 (67%) initially administered TMP-SMX versus 50 out of 68 (74%) initially administered pentamidine (P = 0.402). The survival rates for patients requiring a change in therapy because of failure to respond was 46% (18 out of 39) for the TMP-SMX group compared with 56% (15 out of 27) for the pentamidine group. When a change in therapy was made because of toxicity, survival rates were 97% (30 out of 31) for those receiving TMP-SMX versus 94% (16 out of 17) for those receiving pentamidine. CONCLUSION: TMP-SMX and pentamidine are of equivalent efficacy as initial therapies for PCP in patients with AIDS.  相似文献   
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1. Angiotensin II (AII) binding density and the effect of chronic AII receptor blockade were examined in the rat model of hypoxia-induced pulmonary hypertension. 2. [125I]-[Sar1,Ile2]AII binding capacity was increased in lung membranes from rats exposed to hypoxia (10% fractional inspired O2) for 7 days compared to normal rats (Bmax 108 +/- 12 vs 77 +/- 3 fmol mg-1 protein; P < 0.05), with no significant change in dissociation constant. Competition with specific AII receptor subtype antagonists demonstrated that AT1 is the predominant subtype in both normal and hypoxic lung. 3. Rats treated intravenously with the AT1 antagonist, GR138950C, 1 mg kg-1 day-1 rather than saline alone during 7 days of exposure to hypoxia developed less pulmonary hypertension (pulmonary arterial pressure: 21.3 +/- 1.7 vs 28.3 +/- 1.1 mmHg; P < 0.05), right ventricular hypertrophy (right/left ventricle weight ratio: 0.35 +/- 0.01 vs 0.45 +/- 0.01; P < 0.05) and pulmonary artery remodelling (abundance of thick-walled pulmonary vessels: 9.6 +/- 1.4% vs 20.1 +/- 0.9%; P < 0.05). 4. The reduction in cardiac hypertrophy and pulmonary remodelling with the AT1 antagonist was greater than that achieved by a dose of sodium nitroprusside (SNP) that produced a comparable attenuation of the rise in pulmonary arterial pressure during hypoxia. 5. The data suggest that AII, via the AT1 receptor, has a role in the early pathogenesis of hypoxia-induced pulmonary hypertension in the rat.  相似文献   
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Follistatin and activin A production by the male reproductive tract   总被引:1,自引:0,他引:1  
Follistatin is a binding protein for the activin and inhibin family of hormones, regulating their biological activity. In the male reproductive tract, the interaction of these factors is likely to be involved in the regulation of the proliferation of several cell types. We have investigated the presence of follistatin and activin A in seminal plasma using specific immunoassays and have localized follistatin and activin/inhibin subunits in the adult human testis, prostate and seminal vesicle to establish their likely sources. High concentrations of immunoreactive follistatin were present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in peripheral plasma) and were similar in men with oligo/azoospermia and following vasectomy. Follistatin immunoreactivity was localized to both Leydig and Sertoli cells of the testis, and to epithelial cells of the prostate gland and seminal vesicle, which are likely to be the predominant sources of the hormone in seminal plasma. Activin A was also present in seminal plasma in normal men but was undetectable following vasectomy, thus deriving from the testis. Consistent with this finding, the betaA-subunit was immunolocalized in Sertoli and Leydig cells but was not present in seminal vesicle or prostate gland. The functional significance of the high concentrations of follistatin secreted into seminal plasma by the prostate gland and/or seminal vesicle is uncertain, but they may regulate the biological activity of testis-derived activin A and inhibin B.   相似文献   
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