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排序方式: 共有8378条查询结果,搜索用时 15 毫秒
61.
62.
Surgical management of facial palsy 总被引:1,自引:0,他引:1
Patients with facial palsy present with a multitude of different problems to which individual solutions must be carefully tailored. Although numerous surgical options exist, the results of reconstruction are rarely ideal. This article discusses different surgical procedures for reconstruction of the eye and mouth with special emphasis on the newer technique of microsurgical transfer of muscle tissue for reanimation. 相似文献
63.
Louis G. Martin M.D. Randy D. Cork James O. Wells 《Cardiovascular and interventional radiology》1993,16(2):76-80
Two hundred forty-four consecutive patients (mean age 61 years), including 123 who had technically valid renal vein renin
(RVR) analysis and 121 without RVR data, underwent technically successful percutaneous renal artery angioplasty (PTRA). They
were retrospectively examined to evaluate the utility of RVR analysis in identifying renal hypertension (RVH), predicting
benefit from PTRA, and determining if the lack of knowledge of renin levels significantly affected clinical outcome after
PTRA. Abnormal RVR values were associated with clinical benefit after PTRA in 62 of 93 patients (67% sensitivity, 20% specificity,
72% positive predictive value). Clinical improvement following PTRA occurred in 31 of 37 patients with normal pre-PTRA RVR
values (16% negative predictive value). RVR analysis correctly identified 86 of 117 patients with renovascular hypertension
(74% sensitivity, 16% negative predictive value). Improved blood pressure (BP) control occurred in 72% with abnormal RVR analysis
and 66% of the 121 patients without RVR data (p>0.1). We conclude that the very low negative predictive value significantly
limited the use of RVR analysis in this elderly (mean age 60 years) patient population with a high incidence of mild renal
functional impairment (mean serum creatinine 1.4 mg/dl) and bilateral renal artery stenosis (38%). The lack of pre-PTRA renin
data did not significantly affect clinical outcome. If RVR data were relied upon as the exclusive selection criterion in patients
of this type, many would be prevented from having the benefit of cure or improvement by PTRA. 相似文献
64.
Bronchiectasis developing following colectomy for ulcerativecolitis has been reported in a few cases. This may be the first reportof bronchiectasis developing after colectomy for Crohn's disease. Theclose temporal relationship to colectomy, lack of bacterial pathogensin the sputum, and an impressive response to oral steroids suggest adifference in pathogenesis from idiopathic bronchiectasis.
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65.
The use of different approaches to measurement in drug abuse treatment outcome studies has resulted in a lack of comparability across studies. This paper reviews different approaches to timing of baseline and follow-up periods and to dealing with time periods during which follow-up subjects are not "at risk" for drug use. Length and timing of baseline and follow-up periods are considered as well as periods of time within which specific drug use outcomes are measured. It is suggested that research focus on describing the natural course of drug use both prior to and following treatment, in order to determine the most appropriate length and timing of follow-up periods. It is recommended that investigators report drug use data from both "at risk" and "not at risk" periods, and that they choose methods of controlling for time "at risk" which do not eliminate important drug use data from analyses. 相似文献
66.
Detection bias in the diagnostic pursuit of lung cancer 总被引:2,自引:0,他引:2
Autopsy studies have shown that lung cancer is often not detected during life and that a correct antemortem diagnosis is made preferentially in patients with pulmonary symptoms, in smokers, and in men. The current research was done as a case-control study to determine whether the autopsy suggestions of detection bias in diagnostic pursuit of lung cancer were confirmed by the way that sputum Papanicolaou smears (Pap smears) were ordered in an inpatient setting. The cases were 385 hospitalized patients in whom sputum Pap tests had been newly performed from October 1977 to September 1980. Each case was matched by age, admission date, and admission diagnosis to a control patient who had not received a Pap test. Excluded from the study were patients in whom sputum Pap tests were obligatory (e.g., those with manifestations of hemoptysis) or unnecessary (e.g., those with a previous diagnosis of lung cancer or multiple previous sputum Pap tests). Demographic data, amount and duration of cigarette smoking, and details of clinical manifestations were extracted from the patients' medical records by research assistants blind to the study hypothesis. Compared with controls, the cases had distinctive elevations in odds ratios for chronic cough, recent cough, male sex, and cigarette smoking, which also showed a distinctive dose-response relation. In multivariate analyses, all four of these "risk factors" for selective ordering of a sputum Pap smear remained independently highly significant. In the extreme category, men who smoked and coughed were 22 times more likely to have a sputum Pap test ordered than were nonsmoking women who did not cough. Clinically, the results suggest that women and nonsmokers may be deprived of appropriate diagnosis and therapy unless a diagnostic workup for lung cancer is guided mainly by radiographic findings and presenting manifestations. Statistically, detection bias has probably led to an excessively elevated magnitude for the cigarette smoking-lung cancer association and to a falsely low estimate of incidence rates in women. 相似文献
67.
AIMS: To set up a network for remote consultation using static imaging telepathology via Internet connection between pathologists in different European countries, and to collect some numerical and subjective impressions on the usefulness of this form of telepathology. METHODS: A static image remote consultation network between 11 pathologists in nine European countries was set up; all pathologists were equipped with the same telepathology system. The pathologists formed three subject oriented subgroups concerned with prostate, melanoma, and soft tissue sarcoma pathology. Each pathologist sent and received a small number of cases, and data on each case were collected and analysed. The whole experiment was controlled through a World Wide Web site. RESULTS: A total of 56 case consultations on 34 different cases were exchanged. The average case document contained seven images, and contained 1.97 Mbytes of data. For cases in which data were recorded, average case preparation and remote consultation time was 55 minutes and 9.2 minutes, respectively. Transmission times averaged 3.9 minutes. In subjective impressions, reservations were expressed in several cases regarding the confidence that could be given to the diagnosis from the images presented. CONCLUSIONS: Remote consultation by telepathology via the Internet is now technically feasible and reasonably user friendly, but is only suitable as a method of disease diagnosis in some cases. 相似文献
68.
Immunosuppressive properties of the Mycoplasma arthritidis T-cell mitogen in vivo: inhibition of proliferative responses to T-cell mitogens. 总被引:1,自引:2,他引:1 下载免费PDF全文
We have previously shown that Mycoplasma arthritidis produces a soluble T-cell mitogen (MAM) which is active for most mouse strains that express the alpha chain of the I-E molecule (E alpha) encoded within the murine major histocompatibility complex. The lymphocytes from mice injected intravenously with the MAM exhibited a marked decrease in their ability to respond in vitro to MAM, to phytohemagglutinin, or to concanavalin A T-cell mitogens. Suppression could only be induced in MAM-responsive mouse strains and was most marked 1 to 4 days postinjection. Splenic and node cells and, to a lesser extent, thymic cells from MAM-injected mice could inhibit the ability of lymphocytes from normal mice to respond to MAM and lectin mitogens. A minimum of 2.5 x 10(4) viable cells was required for significant transfer of suppression, and no major histocompatibility complex restrictions were seen. Unlike concanavalin A-induced suppressor cells, which consist of a CD4-, CD8+ T-cell subset, suppressor cells induced by MAM were due to a CD4+ CD8- subset. We hypothesize that MAM may play a role in M. arthritidis-mediated disease by both its inflammatory and immunosuppressive properties. 相似文献
69.
70.
Owens EB Hinshaw SP Kraemer HC Arnold LE Abikoff HB Cantwell DP Conners CK Elliott G Greenhill LL Hechtman L Hoza B Jensen PS March JS Newcorn JH Pelham WE Severe JB Swanson JM Vitiello B Wells KC Wigal T 《Journal of consulting and clinical psychology》2003,71(3):540-552
Using receiver operating characteristics, the authors examined outcome predictors (variables associated with outcome regardless of treatment) and moderators (variables identifying subgroups with differential treatment effectiveness) in the Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD; MTA). Treatment response was determined using parent- and teacher-reported ADHD and oppositional defiant symptoms, with levels near or within the normal range indicating excellent response. Among 9 baseline child and family characteristics, none predicted but 3 moderated treatment response. In medication management and combined treatments, parental depressive symptoms and severity of child ADHD were associated with decreased rates of excellent response; when these 2 characteristics were present, below-average child IQ was an additional moderator. No predictors or moderators emerged for behavioral and community comparison treatments. The authors discuss conceptual and clinical implications of research on treatment moderators. 相似文献