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排序方式: 共有9361条查询结果,搜索用时 125 毫秒
31.
Is colonoscopic screening appropriate in asymptomatic patients with family history of colon cancer? 总被引:1,自引:0,他引:1
Martin A. Luchtefeld M.D. Dale Syverson M.D. Mark Solfelt M.D. John M. MacKeigan M.D. Randall Krystosek M.D. James Waller M.D. Jeffrey W. Milsom M.D. 《Diseases of the colon and rectum》1991,34(9):763-768
Colonoscopy has been advocated by some investigators as the most appropriate means of screening asymptomatic patients with a positive family history of colorectal cancer. However, results of such screening have been widely disparate. The purpose of this study was to evaluate the yield of colonoscopy in a cohort of completely asymptomatic individuals with one or two first-degree relatives with a history of colorectal cancer and to compare this yield with that of colonoscopy in a group of patients with apparent anal bleeding. Patients with possible genetic disorders, such as familial polyposis, were excluded. A total of 160 asymptomatic patients and a comparison group of 137 patients with nonacute anorectal bleeding underwent colonoscopy. Colonoscopy was completed in 143 of the 160 study patients (89 percent) and in all of the comparison patients and did not result in any complications. Twenty-two adenomas were found in 17 study patients (10.6 percent); 16 of the 22 adenomas were less than 1 cm in size. In the comparison group, eight adenomas were identified (5.8 percent of patients). No cancers were identified. The difference in polyp frequency between groups was not significant. The relatively low yield of colorectal neoplasms discovered at colonoscopy in this study may in part be due to the small sample size or to the strict criteria used to define these asymptomatic patients but does not lend strong support to the notion that colonoscopy is an appropriate first step in screening the asymptomatic patient with one or two first-degree relatives with colon cancer. 相似文献
32.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
33.
34.
Robert G Kitchen Dale Mierau David Cassidy Pierre Dupuis 《The Journal of the Canadian Chiropractic Association》1988,32(1):11-15
Congenital dislocation of the hip (CDH) in an adult can accompany or cause mechanical low-back pain. This in turn, can create confusion in making the proper diagnosis. The mechanical alterations caused by CDH create an added strain to the lumbosacral spine. Manipulative treatment for back pain in these patients must not subject the dislocated hips to undue torque. 相似文献
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36.
The actions of dextromethorphan (DXM) on the 50 pS conductance state of theN-methyl-d-aspartate (NMDA) receptor-operated channel were studied using outside-out patches obtained from cultured rat hippocampal pyramidal neurons. DXM (5–50 μM) had no effect on the amplitudes of unitary currents but caused concentration-dependent reductions in channel mean open times and the frequency of channel openings. Channel open probability was reduced in a concentration-dependent manner by DXM and was one-half of the control value at a DXM concentration of 6 μM, with the patch potential held at −60 mV. An IC50 value of 4 μM was obtained for the reduction by DXM of NMDA-evoked rises in [Ca2+]i in cultured rat hippocampal pyramidal neurons loaded with Fura-2. The results were consistent with drug block of the open NMDA channel with an onward (blocking) rate constant of 7.7 × 106 M−1 · s−1 (at −60 mV). The estimated unblocking rate constant was about 10 s−1, a value considerably higher compared to the off-rate constant found for dizocilpine block of the NMDA channel. 相似文献
37.
The purpose of this study was to assess differences in bereavement outcomes between surviving spouses aged 50 and over who remarried within 4-5 years and those who did not. Fifteen bereaved respondents out of 192 in a longitudinal prospective study who later remarried were compared with 15 other matched nonremarried respondents. Analyses of sociodemographic data, standardized measures of depression, life-satisfaction, resolution of grief, and self-perceived ratings of coping, stress, self-esteem, health and social support were performed with correlated t-tests. Statistically significant differences indicated that over time, the remarried subjects displayed more positive outcomes. 相似文献
38.
39.
K E Sletnes F Wisl?ff N Moe P O Dale 《Acta obstetricia et gynecologica Scandinavica》1992,71(2):112-117
The significance of antiphospholipid antibodies in pre-eclamptic women has not been thoroughly elucidated. The purpose of this study was to determine the proportion of pre-eclamptic women who were antiphospholipid antibody positive, and to elucidate the significance of these antibodies regarding growth retardation and neonatal outcome. Positive levels of anticephalin antibodies, which are antiphospholipid antibodies, were detected in 7 (19%) out of 37 pre-eclamptic women, as compared with none of 40 in a control group of normotensive women at similar stage of pregnancy (p = 0.004). The birthweight percentiles of the neonates of anticephalin antibody positive women were significantly lower than those of the neonates of anticephalin antibody negative women (p = 0.018). Four of 7 infants of anticephalin antibody positive women were growth retarded (less than 2.5th percentile). This was a significantly larger proportion than that for anticephalin antibody negative women (3/30) (p = 0.004). The 95% confidence interval for the difference between the two proportions was 0.10 to 0.85. Two of the 7 neonates of anticephalin antibody positive women died during the neonatal period, compared with none of the 30 neonates of anticephalin antibody negative women (p = 0.003). Thus, our study suggests that positive levels of anticephalin antibodies in pre-eclamptic women increase the risk for growth retardation and neonatal death. 相似文献
40.
The use of medical records in research can yield information that is difficult to obtain by other means. When such records are released to investigators in identifiable form, however, substantial privacy and confidentiality risks may be created. These risks become more common and more serious as medical records move to an electronic format. In 1996, the state of Minnesota enacted legislation with respect to consent requirements for the use of medical records in research. This legislation has been widely criticized because--it is claimed--it creates an unnecessary impediment to research. In this article, we show that these arguments rest upon misinterpretation and/or misrepresentation of the 1996 legislation. A consent requirement had actually been present in Minnesota since 1976 (though codified in a patient rights statute rather than a privacy statute). The 1996 law does not require specific consent, as often claimed, but rather only a general authorization. The campaign against the Minnesota legislation appears to have been motivated by concern with respect to the then impending federal privacy rule. The HIPAA rule, as enacted, is in fact less stringent with respect to consent than the Minnesota consent law. On the other hand, the Minnesota consent law has not been effectively applied or enforced. As we change the way we manage sensitive medical information, new efforts are needed to provide protection against the confidentiality risks in research. Patient consent is an important tool in this regard. New instrumentalities are needed to solicit and document consent. 相似文献