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51.
有机硒化合物对白三烯B4生物合成的影响   总被引:4,自引:0,他引:4  
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52.
53.
The advantages and disadvantages of intravenous and intra-arterial digital subtraction angiography of the arteries of the head and neck are discussed. The clinical applications of the two techniques are compared.  相似文献   
54.
BACKGROUND: This study analyzes the role of T lymphocytes and neutrophils (PMN) in intestinal ischemia and reperfusion injury (IRI) using either P-selectin blockade or elimination. METHODS: Using a model of severe mouse warm intestinal IRI, the following groups were performed: group 1: wild type C57BL6 no treatment; group 2: wild type treated with r-PSGL1-Ig; group 3: C57BL6 genetically deficient in P-selectin. Survival was assessed at day 7; intestine was assayed for histopathology, apoptosis, myeloperoxidase (MPO), inflammatory cytokines, hemoxygenase-1 (HO-1), and CD3 lymphocytes. Standard statistical comparison was undertaken. RESULTS: The survival was significantly (P < 0.01) improved in the treatment groups: group 1, 50%; group 2, 90%; group 3, 100%. Graded histopathology and crypt apoptosis were improved in groups 2 and 3. MPO and CD3 positive cells were significantly reduced in groups 2 and 3. A significant reduction in inflammatory/Th1-type cytokines was seen in groups 2 and 3 as compared to group 1. Conversely, a significant increase in Th2-type cytokines and HO-1 production was seen selectively in groups 2 and 3. CONCLUSIONS: This study demonstrates the importance of P-selectin signaling in warm, murine intestinal IRI in that either the blockade of or the genetic deficiency in P-selectin confers a survival advantage and reduction in tissue injury/inflammation. The mechanism involves a reduction of PMN and CD3 T cell infiltration and an alteration in the cytokine microenvironment in favor of a Th2 profile. These data implicate T lymphocyte as an important regulatory cell in this inflammatory process.  相似文献   
55.
Mechanisms by which gastroplasty for morbid obesity causes weight loss are poorly understood. We studied the role of altered gastric emptying in 50 patients before surgery, 1-4 weeks after surgery, and 2-24 months after surgery using technetium-99m pentetate in water for liquid meals and a Tc-99m styrene divinylbenzene copolymer resin in oatmeal for semisolid meals. We determined the emptying half-times of the stomach before and after surgery in the proximal and distal compartments. The proximal compartment emptied promptly in the early and late postoperative periods. The distal compartment emptied liquids at rates similar to those before surgery, while the late postoperative emptying of semisolids was significantly faster. The stoma connecting the two compartments thus permits rapid transit of liquids and semisolids without delay of distal compartment emptying. No correlation was seen between the emptying half-times or changes thereof and eventual weight loss. Delayed gastric emptying is therefore not the mechanism for satiety and weight loss after gastroplasty has been performed.  相似文献   
56.
In this paper we have assessed the extent to which two cohorts of medical students retained skills acquired in two of their basic science courses, i.e. physics and chemistry. It has been shown that a great deal of attrition takes place with respect to factual information and also, therefore, the capacity to apply this information in a relevant manner. It has been argued that this occurs, in part, because students do not appear to regard chemistry and physics as a useful part of their preparation as doctors and, in part, because of the methods used to teach these basic science subjects. Finally, some implications of this preliminary study have been discussed.  相似文献   
57.
BACKGROUND: Despite increasing adoption of clinical practice guidelines in psychiatry, there is little measurement of provider implementation of these recommendations, and the resulting impact on clinical outcomes. The current study describes one effort to measure these relationships in a cohort of public sector out-patients with bipolar disorder.METHOD:Participants were enrolled in the algorithm intervention of the Texas Medication Algorithm Project (TMAP). Study methods and the adherence scoring algorithm have been described elsewhere. The current paper addresses the relationships between patient characteristics, provider experience with the algorithm, provider adherence, and clinical outcomes. Measurement of provider adherence includes evaluation of visit frequency, medication choice and dosing, and response to patient symptoms. An exploratory composite 'adherence by visit' score was developed for these analyses.RESULTS: A total of 1948 visits from 141 subjects were evaluated, and utilized a two-stage declining effects model. Providers with more experience using the algorithm tended to adhere less to treatment recommendations. Few patient factors significantly impacted provider adherence. Increased adherence to algorithm recommendations was associated with larger decreases in overall psychiatric symptoms and depressive symptoms over time, but did not impact either immediate or long-term reductions in manic symptoms.CONCLUSIONS: Greater provider adherence to treatment guideline recommendations was associated with greater reductions in depressive symptoms and overall psychiatric symptoms over time. Additional research is needed to refine measurement and to further clarify these relationships.  相似文献   
58.
The application of electroencephalogram (EEG) biofeedback with reading disability and traumatic brain injury (TBI) is relatively recent. There are many studies regarding the effectiveness (improving attention and IQ scores) of EEG biofeedback in patients with attention deficit hyperactivity disorder, who are known to have a high rate of comorbidity for learning disabilities. This suggests the possibility that EEG biofeedback specifically aimed at remediating reading disability and TBI would be effective. This article provides strong initial support for this idea and provides reason to believe that assessment and training under task conditions are likely to be fruitful. Given the significance of these problems and the absence of very effective alternatives for remediation of these conditions, efforts to complete the needed research seem warranted. Clinical use of this intervention seems to be warranted with informed consent.  相似文献   
59.
OBJECTIVE: The purpose of this study was to evaluate the outcomes of introducing an educational program that teaches medical students how to approach taking relevant and sensitive gynecologic histories and to perform pelvic examinations with the use of role-play with well women from the general community. STUDY DESIGN: Medical students and the women recorded their perceptions of the program over a 2-year period. The outcomes of the program were evaluated by a comparison of medical student perceptions of confidence, competence, and anxiety; the mean number of pelvic examinations that were performed during their course both before and after the introduction of the program and results of students' continuous and summative assessment are given. RESULTS: In the year before the introduction of the program, students performed a mean of 2.6 pelvic examinations (95% CI, 2.1, 3.0) compared with 4.1 pelvic examination (95% CI, 3.8, 4.4) in the first year of implementation and 4.0 (95% CI, 3.7, 4.3) in the second year of implementation (P <.05). Students reported improved competence and reduced anxiety to perform a pelvic examination without supervision (P <.05). All students passed their continuous assessment. Between 92% and 100% of students and women agreed that the program had clear learning objectives, was well organized, and was a useful and appropriate method of teaching that helped prepare them for the clinical setting. CONCLUSION: This pelvic examination educational program has been evaluated positively by students and participant women and has resulted in a significant improvement in the amount of pelvic examination experience that medical undergraduates obtain.  相似文献   
60.
This study evaluated the effect of switching outpatients with schizophrenia and antipsychotic-induced sexual dysfunction to open-label quetiapine treatment. Secondary objectives were to compare the antipsychotic and prolactin-related effects of quetiapine versus prestudy antipsychotic treatment. Eight patients with at least moderately severe antipsychotic-induced sexual dysfunction (N = 7 taking risperidone, 4-6 mg/d; N = 1 taking haloperidol, 10 mg/d) were evaluated prospectively after they switched to 6 weeks of quetiapine treatment. The assessments that we used included evaluations of sexual functioning (Arizona Sexual Experience Scale [ASEX]; McGahuey et al., 2000), psychopathology (Positive and Negative Syndrome Scale [PANSS]; Kay, Fiszbeinm, & Opler, 1997), adverse events, and plasma prolactin levels. Quetiapine was associated with clinically and statistically significant improvement in ASEX total scores (p = 0.008) and significantly decreased PANSS total scores (p = 0.03). Plasma prolactin levels tended to decrease after the transition to quetiapine (p = 0.09). Quetiapine appears to offer an option to reduce antipsychotic-induced sexual dysfunction for outpatients with schizophrenia.  相似文献   
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