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21.

Background  

Colorectal cancer, if detected early, has greater than 90% 5-year survival. However, survival has been shown to vary across racial/ethnic groups in the United States, despite the availability of early detection methods.  相似文献   
22.
We compared nicotine dependence and withdrawal in male alcoholic and control ever-smokers, controlling for relevant demographic and clinical variables. Alcoholics were more likely to meet criteria for moderate or severe nicotine dependence and endorse more nicotine dependence symptoms. Symptoms reported more frequently by alcoholics included: (a) using nicotine in larger amounts or over a longer time than intended; (b) continued use despite problems caused or exacerbated by nicotine; (c) marked tolerance; and (d) experiencing characteristic nicotine withdrawal symptoms. Alcoholics also smoked more heavily. Other than “headaches,” and “decreased heart rate,” alcoholics consistently endorsed nicotine withdrawal symptoms at a higher rate. After controlling for demographic and clinical variables and level of nicotine dependence, only “feel depressed” differed significantly between groups. Our research supports previous findings suggesting that nicotine dependence is more severe in those with a history of alcohol dependence. As a result, alcoholics may experience greater discomfort from nicotine withdrawal upon smoking cessation.  相似文献   
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To define the underlying mechanism of neuromuscular transmission failure induced by anticholinesterases, we simultaneously performed surface recordings of compound muscle action potentials (CMAPs) and intracellular recordings of miniature end-plate potentials (MEPPs), miniature end-plate current (MEPCs), and end-plate potential (EPPs) in rat diaphragms exposed in vitro to 1 × 10?4 to 2 × 10?2 mmol/L neostigmine methylsulfate. At low concentrations of neostigmine, repetitive stimulation of the phrenic nerve resulted in decrement followed by complete recuperation of CMAP amplitudes. This bimodal pattern was associated with maximal end-plate depolarization at the beginning of the stimulation period, increased MEPP amplitudes, and prolonged time constants of MEPC decays. Higher concentrations of neostigmine resulted in a unimodal decline of amplitudes of CMAPs and EPPS, reduced MEPP amplitudes, and a double exponential time course of MEPC decays. These results indicate that low concentrations of anticholinesterases impaired neuromuscular transmission by producing transient depolarization of the end-plate region. Higher concentrations induced desensitization and direct blockade of the end-plate receptor channel, probably in its open conformation. © 1993 John Wiley & Soncs, Inc.  相似文献   
25.
Study Objectives . To determine self-evaluated professional knowledge and competency, functions, demographic information, lifelong learning, degree and training status, practice sites, involvement in pharmacy teaching programs, and salary for recent pharmacy graduates. Design . A survey of recent Bachelor of Science (B.S.) pharmacy graduates of the University of Wisconsin School of Pharmacy. Measurements and Main Results . A total of 371 B.S. pharmacy graduates (55% response rate) provided information. Graduates who had an advanced degree or training (from many programs) after completing their B.S. pharmacy degree, and those who were teaching in pharmacy programs generally had higher self-rated levels of knowledge and competencies. Hospital pharmacists spent less of their work time in dispensing activities (33.82% ± 30.39%) than community pharmacists (61.04% ± 19.97%; t =8.78, df = 288, p<0.001); community pharmacists spent twice as much of their work time counseling and educating patients (16.65% ± 10.47% vs 7.13% ± 7.39%; t = 9.06, df = 288, p<0.001). The amount of time pharmacists spent in dispensing functions had a negative association with knowledge and competencies in the sections on pharmacokinetic and disease process (r=−0.277, p<0.01), patient communications (r=−0.272, p<0.01), and administrative and economic aspects of practice (r=−0.210, p<0.01) for all respondents. Pharmacists reported that they spent 13.78 ± 14.06 hours per month outside work in professional lifelong learning. There was a negative association between the time pharmacists spent dispensing and the time they spent in professional lifelong learning (r=−0.239, p<0.001), and a positive relationship between the time spent in such learning and the time providing information to prescribers and other health care professionals (r=0.214, p<0.001), monitoring patients (r=0.216, p<0.001), and performing primary care activities (r=0.176, p<0.001). Graduates reported a mean yearly salary of $46,879 ± $8183. More hospital pharmacists were involved in teaching (48, 37%) than those practicing in a community setting (19, 12%). Conclusions . Practice site, advanced degree or training, lifelong learning, involvement in teaching programs, and time spent in various professional functions were associated with pharmacists' self-rated knowledge and competencies. (Pharmacotherapy 1994;14(6):712–723)  相似文献   
26.
A technique for transperineal high-dose-rate (HDR) prostate brachytherapy and needle biopsy in a standard 1.5 T MRI scanner is demonstrated. In each of eight procedures (in four patients with intermediate to high risk localized prostate cancer), four MRI-guided transperineal prostate biopsies were obtained followed by placement of 14-15 hollow transperineal catheters for HDR brachytherapy. Mean needle-placement accuracy was 2.1 mm, 95% of needle-placement errors were less than 4.0 mm, and the maximum needle-placement error was 4.4 mm. In addition to guiding the placement of biopsy needles and brachytherapy catheters, MR images were also used for brachytherapy treatment planning and optimization. Because 1.5 T MR images are directly acquired during the interventional procedure, dependence on deformable registration is reduced and online image quality is maximized.  相似文献   
27.
The brains of pathogen-free autoimmune MRL/lpr, NZBWF1 and NZB mice were examined for central nervous system (CNS) inflammation in premoribund 8-week-old animals and at ages when active systemic lupus erythematosus (SLE) was present. CNS inflammation was observed only in MRL/lpr mice. Immunohistochemical studies of brains from young MRL/lpr mice found that infiltrates were composed primarily of CD4+ cells. Older MRL/lpr mice (22 and 26 weeks of age) had CD4+ cells predominantly, but CD8+ and B220+ cells were also present. Perivascular leakage of IgG was a prominent and unexpected finding in the MRL/lpr model. Congenic MRL/+ mice with late-onset autoimmunity had no inflammatory cells in brain tissue, and there was no perivascular staining with IgG or albumin. Our findings suggest that MRL/lpr mice are a useful model for studies of lupus-associated CNS inflammatory disease, and perivascular leakage may be a primary mechanism for entry of IgG into the brain.  相似文献   
28.
Although not extensively researched, psychologic factors have attributed to the growing number of performed breast augmentation procedures. The reported a 293% increase in the cases of cosmetic surgery since 1997. The percent increase in breast augmentation procedures performed in 2003 was up 12 (280 procedures up to 401). As the number of women seeking breast augmentation surgery continues to rise, an increasing number of healthcare professionals are likely to be confronted with questions, concerns, and complications that often accompany the procedure. Consequently, it is important that healthcare providers comprehend the degree to which self-esteem and/or sexuality may affect their patients' outcomes. Healthcare professionals must ascertain specific nursing skills and attitudes while caring for the cosmetic surgical patient. Therefore, the purpose of this research is to gain an understanding of the changes that occur in the levels of self-esteem and sexuality following the breast augmentation. Test of the study hypotheses 1 through 4 failed to be rejected, thereby supporting significant positive relationships between the variables. Statistical analysis of Hypothesis 5 found positive significance between breast augmentation, self-esteem, and the demographic variables-educational level and history of previous cosmetic surgery.  相似文献   
29.
A dry powder aerosol formed of human growth hormone (hGH), lactose and dipalmitoylphosphatidylcholine was assessed for systemic delivery of the hormone in rats. The fate of the protein locally in the deep lung was examined post-delivery. The powder was prepared by spray-drying and presented a primary particle diameter of 4.4 microm and a tap density of 0.069 g/cm(3). The mass median aerodynamic diameter was 4.4 micron in the multi-stage liquid impinger at 60 l/min using a Spinhaler device. The emitted dose and fine particle fraction were 89% and 58%, respectively. Varying the airflow rate from 30 to 90 l/min had limited impact on aerosolization properties in vitro. No hGH dimers or glycation adducts were produced during formulation of the powder. hGH absorbed into the bloodstream with a time to peak of 23 and 52 min and with an absolute bioavailability of 23% and 8% following intratracheal insufflation of the dry powder and intratracheal spray-instillation of a solution of the hormone, respectively. Confocal imaging of rat lung revealed an intense uptake of fluorescein isothiocyanate (FITC)-hGH by alveolar macrophages as early as 1 h post-delivery. A dry powder aerosol made of selected GRAS excipients improved absorption of hGH from the lung over a simple solution.  相似文献   
30.
Due to the shortage of human organs, xenotransplantation is being explored as an alternative to allotransplantation, but immune rejection remains a major hurdle to its implementation. We tested the ability of human CD4+CD25+ T cells (Treg cells) to suppress CD4+ T cell-mediated anti-porcine xenoresponses usingin vitroassays. Human Treg cells were hyporesponsive to porcine cell stimulation and suppressed the proliferative response of CD4+CD25- T cells in a dose-dependent manner, and comparison of the allo- and xenoresponses indicated that more Treg cells might be required to suppress the xenogeneic response than the allogeneic response. Stimulation of CD4+CD25- T cells with porcine cells resulted in secretion of IFN-gamma, TNF-alpha, IL-10, IL-6 and IL-2, and Treg cells suppressed the secretion of these cytokines, as well as the CD4+CD25- T-cell cytolytic response against porcine cells. These results suggest a potential role for Treg cells in promoting xenograft survival.  相似文献   
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