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51.
Because the significant health risks related to postmenopausal osteoporosis can be reduced by estrogen replacement therapy (ERT), this study assessed women's attitudes toward ERT to assess factors that might increase its use. Results showed that women taking ERT were more likely to know that decreased estrogen levels lead to osteoporosis, to perceive that menopause is a medical condition, to believe that natural approaches to menopause are less preferable, to be seeing a gynecologist for care, and to believe that women should take ERT for hot flashes. The study suggests that a systematic educational approach could influence women's willingness to take ERT, especially if the recommended therapy does not cause withdrawal bleeding. 相似文献
52.
Chun Yuan Jay S. Tsuruda Kirk N. Beach Cecil E. Hayes Marina S. Ferguson Charles E. Alpers Thomas K. Foo D. Eugene Strandness 《Journal of magnetic resonance imaging : JMRI》1994,4(1):43-49
Atherosclerotic cardiovascular disease is the most common cause of death in the United States. Investigation of atherosclerotic plaque morphology and composition is important because the findings may be useful in predicting prognosis or response to therapy. This study presents high-resolution magnetic resonance (MR) imaging techniques developed on a 1.5-T whole-body imager with a custom-built surface coil, for characterizing the composition and morphology of plaque removed at carotid endarterectomy. The initial comparison of MR imaging and histologic results showed good correlation. In conjunction with MR angiography, these techniques could be used in in vivo imaging to define the size, location, and contents of atherosclerotic plaque at the carotid bifurcation. 相似文献
53.
Photosensitivity disorders in childhood frequently can be diagnosed and managed in the general dermatology clinic. Occasionally, when diagnostic doubt exists, referral to a specialist unit is required for diagnostic phototesting. Light testing equipment is fickle by nature, making such units uncommon. Phototesting using monochromator or provocation systems takes approximately 45 minutes. Immediate and delayed readings over the following 48 hours as appropriate are required to cover the diagnostic possibilities. Individual diseases are characterized by particular patterns of wavelength dependency and evolution of the abnormal response. Other investigations that may be required are autoantibodies to exclude lupus erythematosus, a porphyrin scan leading to full studies and, on occasion, cell mutation or survival, and chromosome studies for the rarer genophotodermatoses. Good investigative data frequently help clarify the common clinical variants. 相似文献
54.
Inhibitory actions of GABA on rabbit urinary bladder muscle strips: mediation by potassium channels. 总被引:2,自引:1,他引:1
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1. The actions of gamma-aminobutyric acid (GABA) upon rabbit urinary bladder muscle were investigated to determine whether they were mediated through potassium channels. 2. In vitro experiments were undertaken in which bladder muscle strips were caused to contract with carbachol. Addition of GABA or baclofen reduced the size of such evoked contractions in the case of GABA by 20.7 +/- 3.2%, in the case of baclofen by 22.4 +/- 2.2%. 3. Electrical stimulation of autonomic nerves in bladder wall strips also evoked contractions which were significantly smaller in potassium-free Krebs solution. The size of contractions produced by carbachol on the other hand were unaffected by the absence of potassium in the Krebs solution. 4. The inhibitory actions of GABA and baclofen on carbachol-induced contractions of bladder muscle were detected at much lower concentrations in potassium-free compared with potassium containing solutions. 5. The inhibitory effects of baclofen were completely reversed by tetraethyl ammonium chloride between 1 and 5 mM, caesium chloride between 0.5 and 3 mM and barium chloride between 0.5 and 2.5 mM. The actions of baclofen were only partially reversed by 4-amino-pyridine between 1 and 5 mM. 6. It was concluded that the GABAB receptor-mediated inhibitory actions on rabbit urinary bladder smooth muscle cells were produced by activation of potassium channels. 相似文献
55.
R. E. Grant J. A. Schneider E. J. Ferguson P. B. Cummings 《Journal of the National Medical Association》1997,89(8):530-532
More than 250 cases of Cornelia de Lange syndrome have been reported in the medical literature, but not have described the use of hip reconstruction to correct the congenital dysplasia that may be associated with this condition. This article reports the application of a bipolar hemiarthroplasty and acetabular allograft reconstruction for a 32-year old woman with congenital dysplasia and degenerative joint disease of the hip secondary to de Lange''s syndrome. On admission, she was in considerable pain and unable to bear weight on the affected extremity. Her Harris hip score was 25. Following surgical intervention and a well-designed plan of rehabilitation, the patient''s functional status improved markedly. Her Harris hip score was 72, and her pain was alleviated. 相似文献
56.
57.
The characteristics of 254 cadaveric kidneys were evaluated and the incidence of immediate function identified. The Belzer perfusate was used primarily (n = 140) and secondarily (n = 14) in combination with pulsatile machine perfusion. These two groups were compared with a previous group of kidneys machine-perfused with silica gel (cryoprecipitated human plasma). The incidence of immediate function of the group primarily perfused with Belzer perfusate was statistically significantly improved over that of the silica gel. The secondarily perfused Belzer group, "imported" kidneys previously preserved with simple cold storage, had notably longer periods of preservation and higher resistances on the machine. However, 100% of this group functioned immediately. Other findings in this study show that the Belzer perfusate allows for improved parenchymal function posttransplant, as noted by a more rapid clearance of serum creatinine posttransplant. When comparing the immediate function group with those suffering early dysfunction, there is a statistically significant increased resistance on the machine in the latter group. This allows for prediction of immediate function based on perfusion characteristics of the kidney. The Belzer perfusate, composed of metabolic substrates for high-energy phosphate production, improves the incidence of immediate function in machine-perfused kidneys, as well as improved qualitative function posttransplant. It also is effective as a "rescue" mechanism in previously simple cold-stored (ATP-depleted) kidneys. 相似文献
58.
The effect of antigen deprivation on thymus-dependent and thymus-independent lymphocytes in the small intestine of the mouse 总被引:11,自引:4,他引:11
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Isografts of foetal small intestine, implanted under the kidney capsules of adult mice grow normally and, despite the lack of intraluminal antigenic stimulation, are populated by thymus-dependent and thymus-independent lymphocytes. The Peyer's patches in these grafts are very small, lack germinal centres and can be shown to have small thymus-dependent areas.
Quantitative intraepithelial lymphocyte counts were carried out in normally sited small intestine of immunologically intact and thymus-deprived mice, and in grafts implanted in intact and thymus-deprived mice. Counts were also performed in a group of neonatally thymectomized and control mice. The results show a significant depletion of intraepithelial lymphocytes in neonatally thymectomized mice, and a profound reduction in numbers of intraepithelial lymphocytes in grafts, deprived of antigen, when compared with normally sited intestine of the same age.
相似文献59.
D. J. P. Ferguson A. A. McColm D. M. Ryan P. Acred 《Virchows Archiv : an international journal of pathology》1986,410(1):43-48
Summary The initial colonization, byStaphylococcus aureus, of the catheter damaged aortic valve and aorta of the rabbit, was examined by light and electron microscopy at 15 min, 3 h and 24 h post inoculation (PI). At 15 min PI, the majority of bacteria (80%) were located on the lateral surfaces of the thrombic vegetations while 20% were attached directly to the connective tissue of the aortic valve and aorta in areas where the endothelial lining was disrupted. By 3 h the bacteria on the thrombic vegetations were covered by fibrin. At this time, the bacteria both within the vegetations and on the surface of the vasculature were undergoing multiplication to form small groups. The precipitation of thrombus around the bacteria attached to the surface of the aorta to form microscopic infected vegetations had occurred by 24 h PI. The colonizing bacteria did not elicit any phagocytic response. The colonization of the cardiovasculature byStaph. aureus did not necessarily require pre-existing vegetations. 相似文献
60.
2-Hour cytomegalovirus pp65 antigenemia assay for rapid quantitation of cytomegalovirus in blood samples
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Of 109 blood samples tested for cytomegalovirus (CMV) antigenemia, 18 (16.5%) were positive. CMV Brite detected 13 and CMV Brite Turbo detected 16 of the 18 positives. There was no significant difference in the number of positive cells detected per sample. The seven discrepant samples contained a median of only one positive cell. 相似文献