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101.
102.
Colonoscopy and bacteraemia.   总被引:3,自引:0,他引:3       下载免费PDF全文
G P Coughlin  R N Butler  M H Alp    A K Grant 《Gut》1977,18(8):678-679
A prospective study was performed on 35 patients undergoing colonoscopy. Aerobic and anaerobic blood cultures before, during and after the investigation failed to demonstrate bacteraemia in any instance.  相似文献   
103.
BACKGROUND: Excessive first ray mobility has been implicated as the cause of many forefoot abnormalities. The association between hypermobility and forefoot pathology is controversial, and this is largely related to the difficulty in quantifying first ray motion. Manual examinations have been shown to be unreliable. Klaue etal. developed a device consisting of a modified ankle-foot orthosis with an attached micrometer to objectively measure first ray mobility. The purpose of this study was to evaluate the validity and reliability of this device. METHODS: Sixteen fresh-frozen, below-knee amputation specimens with hallux valgus were used for the study. The study was divided into two parts. Part I was an analysis of the validity of the Klaue device; first ray dorsal displacement was measured on lateral radiographs following manual manipulation, and values were statistically compared to the Klaue device measurements. Part II of the study was an evaluation of intraobserver and interobserver agreement. Two clinicians used the Klaue device on each of the cadaver limbs, and values of first ray sagittal mobility were recorded and compared. RESULTS: The mean value of first ray mobility measured with the Klaue device was 7.5 mm and the average displacement measured from the lateral radiographs was 7.4 mm. Paired t-testing showed no significant difference between the Klaue and radiographic measurements (p = 0.83). The mean first ray mobility by examiners 1 and 2 with the Klaue device were identical (10.5 mm), and statistical analysis showed no significant interobserver or intraobserver differences. CONCLUSIONS: The results confirm the validity of the Klaue device and limited variability of measurements between experienced users.  相似文献   
104.
BACKGROUND: The proximal crescentic osteotomy is an effective technique for correcting a widened 1-2 intermetatarsal angle associated with moderate to severe hallux valgus deformities. However, postoperative dorsal malunion at the osteotomy site from loss of fixation has been reported. The purpose of this study was to evaluate the biomechanical characteristics of a new custom-designed plate and compare it to the traditional screw and Kirschner wire construct. METHODS: Twenty identical Sawbone (Pacific Research Laboratories, Vashon, WA) models were used for the study. A proximal crescentic osteotomy was done on each specimen, and 10 were secured with a dorsomedial plate (group I). The remaining 10 models were fixed with a screw and Kirschner wire combination (group II). Physiologic cyclical testing was done using a mechanical testing machine to evaluate dorsal displacement of the metatarsal. Load-to-failure testing was then done on each specimen to evaluate ultimate failure and stiffness of the constructs. Groups I and II were statistically compared using paired t-testing. RESULTS: The mean dorsal displacement of the first metatarsal head after 1000 cycles was 0.19 mm (SD = 0.09 mm) for group I and 0.28 mm (SD = 0.15) for group II, and the difference was not statistically significant (p = 0.08). Group I demonstrated statistically superior ultimate failure strength (95.2 N) and stiffness (26.8 N/mm) compared to group II (73.7 N, 19.4 N/mm). CONCLUSIONS: Based on Sawbone models, dorsal plate fixation of proximal crescentic osteotomy provides a stronger construct than the traditional screw and Kirschner wire construct. The clinical use of the specially-designed plate described in this study may lower the incidence of dorsal malunions that occur postoperatively and may decrease the occurrence of transfer metatarsalgia. Its application may be particularly helpful in patients with poor bone quality.  相似文献   
105.
106.
Since the introduction of mediastinoscopy, there has been a great deal of discussion regarding indications for this technique and the significance of positive findings. We undertook this study to determine the role of clinical staging and the value of routine mediastinoscopy in the treatment selection of patients with primary lung cancer.From 1975 to 1983, 1,259 consecutive patients with proven and operable lung cancer underwent preresection mediastinoscopy. Nodes were sampled at three levels, and findings were recorded by location, invasiveness, and histology. There were no operative deaths, but 3 patients had a major complication.Mediastinoscopy was positive in 339 (27%) patients and negative in 920 (73%). In the group with positive findings, 303 patients had no operation because a curative resection was not possible (extranodal metastases, 180; location, 76; histology, 47). No patient survived 5 years, and only 4% survived 2 years. Of the 36 patients considered to have operable disease, 28 underwent resection with a projected 5-year survival of 18%. In the group with negative findings, 89% had a curative resection with a hospital mortality of 3.2% and 5-year survival of 53%. When results of mediastinoscopy were correlated with findings at thoracotomy, the sensitivity of the test was 93% on nodes in the superior mediastinum and the specificity, 100%.This study shows that mediastinoscopy is safe and is an accurate indicator of the presence or absence of tumor in superior mediastinal nodes. If positive nodes are found, a curative resection is generally not possible, thoracotomy is avoided, and the overall survival is low.  相似文献   
107.
A new approach to the problem of retinal neovascularization   总被引:3,自引:0,他引:3  
Tumor cells introduced into the rabbit vitreous produced a form of retinal neovascularization, but only when the tumor cells were in direct contact with the vascularized retina. This contrasted with the production of neovascularization at a distance of several millimeters in other angiogenesis models. An extract of adult rabbit vitreous was found to inhibit the growth of limbal neovascularization induced by tumors implanted in the rabbit corneal stroma. The experimental model of retrolental fibroplasia provides a bioassay to investigate further the apparent inhibitory substances in the vitreous.  相似文献   
108.
Temporal changes in tPA and PAI-1 after maximal exercise   总被引:1,自引:0,他引:1  
PURPOSE: Although fibrinolysis increases with acute exercise, it decreases rapidly during the postexercise period. Therefore, the time point at which blood samples are collected postexercise could affect reported tissue plasminogen activator (t-PA) and/or plasminogen activator inhibitor-1 (PAI-1) levels. The purpose of this study was to determine the time course of t-PA and PAI-1 changes after acute maximal exercise. METHODS: Eight healthy males performed a graded maximal exercise test on a treadmill. Venous blood samples were collected using an indwelling catheter before exercise and at 1, 2, 4, 6, 8, and 10 min postexercise. Mean differences in t-PA activity, t-PA antigen, and PAI-1 activity at each time point were assessed using a repeated measures ANOVA. Post hoc means comparisons were performed by contrasting the 1-min postexercise value against all other time points. RESULTS: Both t-PA activity and t-PA antigen significantly increased from pre- to postexercise (P < 0.05). t-PA activity did not change from 1 to 2 min postexercise but decreased significantly at 4 min postexercise. Likewise, t-PA antigen remained elevated from 1 to 2 min postexercise but decreased at 4 min postexercise. PAI-1 decreased from pre- to postexercise but did not change during the 10-min postexercise period. CONCLUSION: To accurately evaluate the t-PA response to acute exercise, blood samples should be collected within 2 min after the cessation of exercise.  相似文献   
109.
BACKGROUND: Historically, the Mississippi Delta region has been medically underserved. This may lead to lower cancer prevention efforts and higher breast or cervical cancer mortality rates. METHODS: Death rates for 1979 through 1998 were calculated for Mississippi Delta women and for women living elsewhere in the US. RESULTS: Breast cancer mortality in the Delta was similar to that elsewhere in the US in recent years for both black and white women, but rates were lower in the Delta in the early years of the study period. Overall, cervical cancer mortality was similar in the two areas but rates declined more rapidly elsewhere in the US than in the Delta. Breast and cervical cancer mortality was higher among black women than among white women in both areas. Cervical cancer mortality was higher among white rural and black urban women in the Delta than their counterparts elsewhere. CONCLUSION: These results can guide prevention activities for reducing mortality from these diseases.  相似文献   
110.
The purpose of the study was to determine breast and cervical cancer screening among women living in the Mississippi Delta region. Using data from the Behavioral Risk Factor Surveillance System for 1999--2000, we determined the prevalence of mammography (women 40 years and older, n = 6,028) and Pap testing (women 18 years and older, n = 6,502) within the past 2 or 3 years, respectively. We examined predictors of testing and compared results with those for women living elsewhere in the United States. Among Delta women, 69.4% (95% confidence interval [CI] 67.9% to 70.9%) had a mammogram and 85.5% (95% CI 84.3% to 86.6%) a Pap test. Mammography prevalence was lower among black and white Delta women than among black and white women elsewhere. Pap testingwas lower among older (65 years and older) Delta women or women who did not visit a doctor within the past year than among their counterparts elsewhere. Additional interventions are needed to meet the goals of Healthy People 2010 for all women.  相似文献   
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