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91.
The association between perceptions about condom use among one's peers, beliefs about new HIV treatments, and HIV sexual risk behavior was examined in a large urban sample ( N = 454) of gay and bisexual men in the Southeast. Results partially confirmed the hypothesis that men who endorsed new HIV treatment beliefs would report lower norms for condom use and higher HIV sexual risk behaviors than men who failed to endorse HIV treatment beliefs but with casual, and not main, partners. Moreover, results confirmed the hypothesis that the association between HIV treatment beliefs and unprotected sex would be partially mediated by peer condom norms. Results suggest social interventions are needed to promote condom norms in the social context of new HIV treatments. © 2006 Wiley Periodicals, Inc. 相似文献
92.
93.
Roger Baker BA PhD FBPsS 《Journal of advanced nursing》1988,13(5):631-639
A ward-based token economy programme which formed one part of a larger rehabilitative service for long-stay psychiatric patients is described. The clinical effectiveness of the programme is examined by the use of various nursing, psychological and psychiatric assessments before and after the patients' treatment on the ward, and the progress of former patients is followed-up as they move to different parts of the rehabilitation service. Significant clinical gains in patients' psychiatric symptomatology and problem behaviour on the ward are reported, although there were indications that improvement was not fully maintained as the patients moved on to other parts of the service. Comparison of the present clinical programme with the earlier research programmes on the ward indicated that the present regime was superior. The advantages and problems of token economy as a rehabilitative facility are discussed, outlining the various different roles for token economy with psychiatric rehabilitation. Finally, the future of token economy for long-stay patients is considered, questioning whether it might more appropriately be replaced by other structured ward programmes. 相似文献
94.
Roger E. Kelley MD Alireza Minagar MD Bradford J. Kelley Regina Brunson RVT 《Journal of neuroimaging》2003,13(1):85-87
Meningovascular syphilis is now quite uncommon, but there have been increasing reports in patients immunocompromised with human immunodeficiency virus. The response of syphilis affecting the central nervous system to antibiotic therapy remains a challenge. This is an even greater challenge in patients who have underlying compromise of the immune system. The authors present a 46-year-old male with recurrent stroke who was found to have cerebrospinal fluid compatible with syphilitic involvement of the central nervous system and a cerebral arteriogram, which revealed focal narrowing of the right middle cerebral artery. The baseline transcranial Doppler study demonstrated increased mean and peak flow velocity within the right middle cerebral artery. Despite a 10-day course of intravenous penicillin, with substantial improvement in the cerebrospinal fluid results, this flow velocity elevation persisted, in a remarkably consistent pattern, over a 4-month follow-up period. Thus, the involved vessel remained patent following treatment, but no clear resolution of the stenotic lesion was observed. 相似文献
95.
Objective: Microvascular pericytes may contract in two different ways: In the first, a circumferential or radial mechanical force applied at right angles to the long axis of the vessel may constrict the underlying vessel affecting blood flow and transmural pressure. Retraction and elongation of pericyte processes may also occur tangentially and at right angles to the vessel axis and alter microvessel permeability by changing the amount of ablumenal surface covered or the openness of interendothelial junctions. In this study, cultured pericytes were utilized as a model experimental system to determine if vasoactive stimulation changes their shape in a manner consistent with this hypothesis. Methods: Pericytes cultured from isolated rate capillaries were subjected to angiotensin II and histamine. Their response was monitored by measuring the area of nonyielding substrate covered by the pericytes and the manner in which their shape changed. Shape changes were quantified by calculating the surface area: perimeter perimeter ratios. Results: Histamine significantly reduced surface area covered and the surface area: perimeter ratio. The pericyte processes retracted, resulting in elongated, spindle-shaped cells. These effects were nullified by the H1 blocker diphenhydramine suggesting a receptor-specific response. Angiotensin II also elicited contraction and reduced surface area, but the cells contracted laterally and longitudinally. The surface area: perimeter ratios also decreased. Conclusions: These results indicate that pericytes are capable of two types of contractile responses in culture, depending on the specific vasoactive stimulus. 相似文献
96.
Pierre E Wallemacq Arnaud Capron Roger Vanbinst Eric Boeckmans Jean Gillard Bertrand Favier 《American journal of health-system pharmacy》2006,63(6):547-556
PURPOSE: The permeability of 13 different gloves to 13 cytotoxic agents under controlled dynamic conditions is described. METHODS: Thirteen cytotoxic agents were prepared at the highest concentrations normally encountered by pharmacy personnel. Four glove types--neoprene, natural rubber latex, nitrile, and vinyl--were exposed to the cytotoxic agents for 15, 30, and 60 minutes. Tests were conducted using the middle finger of each glove. Linearity, reproducibility, and sensitivity were evaluated for each drug tested. Assays were run using liquid chromatographic tandem mass spectrometry (LC/MS/MS) and high-performance liquid chromatography with ultraviolet light (HPLC-UV). Permeability testing was conducted using an original system designed to evaluate dynamic constraints, such as rubbing, stretching, and tension. RESULTS: Linearity by LC/MS/MS and HPLC-UV was confirmed at concentrations up to 1000 ng/mL for all drugs. Most glove materials were permeable at rates below ASTM recommendations over the one-hour testing period. Vinyl was the most permeable material. Carmustine permeated the widest variety of materials. Due to the high sensitivity of the analytic methods, all materials displayed low but significant permeability for at least one drug after one hour. Higher resistance to permeation was recorded for all neoprene, some natural rubber latex, and one nitrile glove. CONCLUSION: Neoprene, natural rubber latex, and nitrile gloves displayed the highest resistance to permeation of the 13 cytotoxic agents studied. Additional factors, such as duration of exposure, glove thickness, and drug liposolubility and molecular weight, also affected permeability. 相似文献
97.
98.
Andrew J Lawrence Andrew D Blackwell Roger A Barker Francesca Spagnolo Luke Clark Michael R F Aitken Barbara J Sahakian 《Movement disorders》2007,22(16):2339-2345
Dopamine replacement therapy (DRT) for Parkinson's disease (PD) has recently been linked to the development of a number of nonmotor behavioral control problems. Punding, one of these nonmotor problems, is a term used to describe complex, purposeless stereotyped behaviors such as the repetitive handling or sorting of objects. A self-report questionnaire was adapted to assess punding in the context of dysfunctional hobby-related activities. We report the results of a survey of PD outpatients from a PD research clinic (n = 141) and non-PD controls (n = 103); conducted to identify clinical and psychological factors predictive of punding behaviors. The PD group reported hobbies and activities, which scored significantly higher on the Punding Scale than controls. Higher impulsivity, poorer disease-related quality of life, younger age of disease onset, and concomitant daily medication dosage from dopamine receptor agonists were independently predictive of higher Punding Scale scores in the PD group. These findings are similar to those seen in dopamine dysregulation syndrome, and provide further evidence for the role of impulsivity and age at disease onset in DRT-related nonmotor behavioral problems in PD. 相似文献
99.
100.