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101.
102.
R Ginsburg 《Hospital practice (Office ed.)》1983,18(4):165-9, 173-6
Although coronary vasospasm may occur in vessels that arteriographically appear fully patent, histologically there is virtually always some evidence of atherosclerotic lesions. Whether or not atherosclerosis can be angiographically documented, all patients with coronary vasospasm require therapy. Calcium channel blockers may actually alter the course of the disease process as well as relieve symptoms. 相似文献
103.
The present study examined the concurrent and prospective relation between a select number of potential predictors and symptoms
of anxiety among a high-risk community sample of 149 predominately African American children. Parent and child reports of
anxiety were assessed in the first and seventh grade. Six domains of childhood risk factors (i.e., Loss-Death, Loss-Separation,
Social Adversity, Negative Family Environment, Academic Difficulties, and Peer Rejection) were assessed using multiple informants
in the first grade. Results indicated that children who experienced a more negative family environment, had a greater number
of losses and deaths, and experienced academic failures in the first grade exhibited higher levels of anxiety (concurrently
and/or at the six year follow-up). Findings provide empirical support to etiological models that posit both parental/familial
and environmental factors contribute to the development of heightened anxiety in children. 相似文献
104.
BACKGROUND: Neurosteroids with a 3 alpha-hydroxy orientation share pharmacological effects with ethanol, increase in brain after ethanol administration, and may mediate ethanol effects. 3beta-hydroxy neurosteroids antagonize in vitro and some, but not all in vivo effects of ethanol and 3 alpha-hydroxy neurosteroids. METHODS: We assessed the discriminative stimulus and rate altering effects of alphaxalone, a 3 alpha-hydroxy neurosteroid, and epiallopregnanolone, a 3beta-hydroxy neurosteroid, in rats trained to discriminate either 0.8 g/kg or 1.2 g/kg ethanol. The ability of epiallopregnanolone to antagonize the discriminative stimulus or rate-altering effects of ethanol or alphaxalone was also assessed. RESULTS: Ethanol had similar discriminative ED50s (0.5 g/kg) in both groups; however rats trained with the lower ethanol dose were more sensitive to rate-decreasing effects of ethanol. Alphaxalone occasioned ethanol-appropriate responding in both training groups, although less effectively in rats trained on the lower ethanol dose (maximum 65% versus 80% ethanol-appropriate responding). No difference in sensitivity to the rate-decreasing effects of alphaxalone was present between groups. Epiallopregnanolone did not reliably occasion ethanol-appropriate responding in either training group, and rats trained on the lower ethanol dose were slightly more sensitive to epiallopregnanolone rate decreasing effects. Epiallopregnanolone did not alter any effects of ethanol or alphaxalone. CONCLUSIONS: Our results agree with previous reports that 3 alpha-hydroxy neurosteroids occasion ethanol-appropriate responding, while 3beta-hydroxy neurosteroids do not; as well as reports showing no antagonism of the discriminative stimulus or rate-suppressant effects of ethanol or 3 alpha-hydroxy neurosteroids by 3beta-hydroxy neurosteroids. Results of the present study demonstrate that ethanol and 3 alpha-hydroxy neurosteroids share discriminative stimulus effects. However, these results are inconsistent with the hypothesis that such neurosteroids mediate the discriminative stimulus of ethanol. 相似文献
105.
Ginsburg PB 《The New England journal of medicine》2004,351(16):1591-1593
106.
Ginsburg S Schreiber M Regehr G 《Advances in health sciences education : theory and practice》2004,9(2):137-145
PURPOSE: The selection process for residency positions is sometimes seen as being "opaque" and unfair by students, and can be a significant source of student stress. Yet efforts to clarify the process may not have helped reduce student stress for a number of reasons. This paper examines the nature of the knowledge that students possess and describes the implications for future efforts at addressing this knowledge. METHODS: The current study assessed the perceptions of three groups (selection committee members, faculty advisors, and students) at a single institution using two evaluation methods (ranking of a context-free list of variables, and an assessment of the legitimacy of 20 "common language" opinion statements comparing the variables). RESULTS: For the context-free ranking of variables, ICC's were moderately high for all three groups (0.479-0.584) and the disattenuated correlations were very high (0.872 to 0.946). By contrast, when more contextually relevant opinion statements were evaluated, the ICC's were much more variable (less than 0 to 0.279), the correlations (where calculable) were lower (0.449 to 0.547), and inconsistencies of opinion regarding particular variables became apparent. CONCLUSIONS: To properly understand the true nature of the opinions that are being held by the various groups it is necessary to use statements that reflect the vernacular of the "rumour mills" that are the common source of student information. 相似文献
107.
Using two luminescence-inducing cocktails, two distinct patterns of inhibition of light by different anti-oxidants have been identified, comprising Group A, in which a complete inhibition of light emission which is then followed by re-emergence of light, forming apparent S-shaped curves or similar shapes. This light pattern is induced by the “classical” anti-oxidants, ascorbate, vitamin E, uric acid, thiols, deferoxamine, as well as by anti-oxidant agents present in plasma, saliva, urine and in extracts derived from black coffee, and Group B, in which a gradually emerging “mound”-shaped pattern of light was seen with extracts from the Tibetan plant mixture PADMA-28, elderberry (Sambucol), grape seeds, green and black teas, apple, parsimony, red wines, edible oils and SOD. While the results with the Group A agents point to the presence of probably a single, major, anti-oxidants relatively sensitive to oxidation, Group B agents probably include a mixture of anti-oxidants which are more resistant to oxidation. It was also shown that agents from Group B could protect agents from Group A against consumption by the oxidants generated by the cocktails. It is proposed that these simple to use cocktails which probably generate a multiplicity of oxidants mimicking those generated by activated phagocytes, can rapidly assess the total anti-oxidant capacities (TAOC) in body fluids derived from patients suffering of excessive oxidative stress. Also, this technique may be useful in determining the content of dietary anti-oxidants recommended as supplements to enhance the resistance against excessive oxidation of lipids. 相似文献
108.
109.
Randolph JF Ginsburg KA Leach RE Blacker CM Moghissi KS Diamond MP Reame NE 《Fertility and sterility》2003,80(2):320-327
OBJECTIVE: To determine whether women with rigorously defined unexplained infertility demonstrated altered GnRH secretion, as reflected by serum LH secretion patterns. DESIGN: Prospective observational study. SETTING: National Center for Infertility Research at Michigan. PATIENT(S): Nine women with rigorously defined unexplained infertility and 11 healthy, parous age-matched control women.Gonadotropin-releasing hormone (25 ng/kg) as a bolus injection. MAIN OUTCOME MEASURE(S): Daytime pulse patterns of LH secretion measured every 10 minutes; mean serum concentrations of LH, FSH, E(2), P, PRL, and cortisol; and response to a physiologic dose of GnRH in the early follicular, late follicular, mid-luteal, and late luteal phases of the same menstrual cycle. RESULT(S): Serum LH pulse frequency and pulse amplitude and LH secretion in response to a physiologic bolus of GnRH were not significantly different in unexplained infertility patients at any phase of the cycle. Luteinizing hormone pulse frequency and amplitude, as well as response to GnRH, varied significantly across the cycle. Mean early follicular serum LH and FSH concentrations were significantly higher in unexplained infertility patients than in fertile control subjects (LH: 5.31 +/-.51 vs. 4.03 +/-.33 [mIU/mL +/- SEM]; FSH: 5.81 +/-.63 vs. 3.80 +/-.45) but were not different at any other phase of the cycle. CONCLUSION(S): These data do not support the hypothesis that unexplained infertility is caused by an abnormality in pulsatile GnRH secretion or abnormal pituitary sensitivity to GnRH. However, the results are consistent with a difference in negative feedback from the ovary to the pituitary in unexplained infertility patients that is suggestive of diminished ovarian reserve. 相似文献
110.