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71.
72.
A case of an unusual degloving injury of the descending colon resulting from a crushing injury to the mid-torso is reported. The diagnosis was made at laparotomy for associated injuries. The colon was stripped of its muscle layers and mesentery for 10 cm without perforation. 相似文献
73.
M Aránzazu Partearroyo H Ostolaza F M Go?i E Barberá-Guillem 《Biochemical pharmacology》1990,40(6):1323-1328
The effects of a variety of detergents (non-ionic, ionic and bile derivatives) on B16 melanoma cells have been examined. Two main effects can be clearly differentiated: loss of cell viability and cell lysis. Under our conditions, cell-surfactant interaction is highly dependent on the nature of the amphiphile (more specifically, on its critical micellar concentration). Loss of cell viability occurs at surfactant concentrations below the critical micellar concentration, i.e. the incorporation of detergent monomers into the cell membranes is enough to impair their barrier function, so that Trypan Blue is no longer actively secreted outside the cell. On the other hand, cell lysis only occurs at or near the critical micellar concentration of the detergent, i.e. when the bilayer-micelle transition may take place. Comparative studies using B16 cells and phospholipid vesicles indicate that the amount of detergent required to induce cell lysis is the same that produces disruption of the lipid bilayer. Thus, our results suggest that membranes are the primary target for the toxicologic effects of surfactants on cells. Moreover, they provide a rationale for the interpretation of other studies in this field: previous results from different laboratories are shown to fit very well our data. 相似文献
74.
75.
Paul K Y Lam W K Ho Manwa L Ng William I Wei 《Otolaryngology--head and neck surgery》2007,136(3):440-444
OBJECTIVE: To justify the application of medialization thyroplasty in Chinese patients with symptomatic cancer-related unilateral vocal fold paralysis (UVFP). STUDY DESIGN AND SETTING: Retrospective chart review from February 2000 to March 2006. RESULTS: Eighty-seven Chinese patients undergoing medialization thyroplasty for UVFP were included; there were no significant differences between the cancer-related and benign groups in terms of the speech and swallowing rehabilitation outcome and the perioperative complication rate (P > 0.05). The median survival time of cancer-related UVFP patients from the date of medialization to death was 129 days. Age more than 65 years was identified as the only factor for a shorter survival period after medialization (P = 0.040). CONCLUSION: Medialization thyroplasty restores satisfactory speech and swallowing and has a low perioperative complication rate in Chinese patients with cancer-related UVFP. Postmedialization survival period was also reasonable. SIGNIFICANCE: Medialization thyroplasty is a justifiable treatment option for cancer-related UVFP. 相似文献
76.
77.
Anna Szymańska Elżbieta Korobowicz Wiesław Gołąbek 《European archives of oto-rhino-laryngology》2006,263(7):657-660
Nasopharyngeal angiofibromas occur predominantly in males in their puberty and adolescence; the incidence in other age groups and in women is exceptional. This report describes a case of a 57-year-old woman with nasopharyngeal angiofibroma presenting typical radiological findings in computed tomography, MR imaging and angiography. The tumour was successfully removed and histopathological examination confirmed the diagnosis. In 6 years follow-up the patient is free of symptoms. 相似文献
78.
Ngai Suk Wai; Tang Oi Shan; Lao Terence; Ho Pak Chung; Ma Ho Kei 《Human reproduction (Oxford, England)》1995,10(5):1220-1222
Intravaginal misoprostol has been shown to be effective forcervical priming before a surgically induced abortion. The objectivewas to investigate the effectiveness of oral misoprostol incervical dilatation prior to vacuum aspiration between the 6thand 12th weeks of pregnancy. The results showed that in nulliparouspatients, the median cervical dilatation in the treatment group(7.8 mm) was significantly greater than that in the placebogroup (3.7 mm). In multiparous patients, the difference wasalso statistically significant (9.8 versus 6.0 mm). The easeof dilatation, assessed subjectively by the operating surgeons,was significantly improved in the treatment group. There wasalso a significant reduction in the duration of the operationand in the mean blood loss in the treatment group. The side-effectsencountered in the treatment group were mild and well acceptedby the women. Oral misoprostol is an effective and safe methodfor cervical dilatation prior to vacuum aspiration in firsttrimester pregnancy. 相似文献
79.
Gert Jan Laarman Menco G. Niemeyer Albert V. G. Bruschke Fred J. Verzijlbergen T. Liam Go Ernst E. van der Wall Carl A. P. L. Ascoop 《European journal of nuclear medicine and molecular imaging》1989,15(5):239-243
To establish test specific normal limits for quantitative analysis of uptake and washout of 201Tl after dipyridamole infusion combined with low level exercise, 20 healthy volunteers were studied with low likelihood of coronary artery disease (CAD) assessed by a stepwise probability analysis based on age, sex, symptoms, resting electrocardiogram, and exercise electrocardiography. Likelihood of CAD in these volunteers was calculated as 1%. After dipyridamole infusion combined with low level exercise, one volunteer complained of headache; no other side effects were observed. There were no chest pain complaints. Maximal hemodynamic changes were achieved during the 6th and 7th min of the test. No ST segment depression was recorded. Visual analysis of the 201Tl scintigrams was normal in all volunteers. Mean regional washout at 4 h was 44.37%±2.11%. The regional washout in the 70° LAO view (46.65%±1.10%) was significantly higher than in the anterior and 30° LAO views (43.44%±1.50% and 43.02%±1.45%, respectively). Profiles of uptake and washout of 201Tl were different after dipyridamole infusion combined with low level exercise as compared to maximal exercise. Thus, in quantitative analysis of 201Tl scintigraphy after dipyridamole infusion in conjunction with low level exercise as applied in the present study, it is mandatory to use normal limits of uptake and washout of 201Tl derived from healthy volunteers who underwent the same combined protocol. 相似文献
80.
Effects of x-ray and CT image enhancements on the robustness and accuracy of a rigid 3D/2D image registration 总被引:2,自引:0,他引:2
A rigid body three-dimensional/two-dimensional (3D/2D) registration method has been implemented using mutual information, gradient ascent, and 3D texturemap-based digitally reconstructed radiographs. Nine combinations of commonly used x-ray and computed tomography (CT) image enhancement methods, including window leveling, histogram equalization, and adaptive histogram equalization, were examined to assess their effects on accuracy and robustness of the registration method. From a set of experiments using an anthropomorphic chest phantom, we were able to draw several conclusions. First, the CT and x-ray preprocessing combination with the widest attraction range was the one that linearly stretched the histograms onto the entire display range on both CT and x-ray images. The average attraction ranges of this combination were 71.3 mm and 61.3 deg in the translation and rotation dimensions, respectively, and the average errors were 0.12 deg and 0.47 mm. Second, the combination of the CT image with tissue and bone information and the x-ray images with adaptive histogram equalization also showed subvoxel accuracy, especially the best in the translation dimensions. However, its attraction ranges were the smallest among the examined combinations (on average 36 mm and 19 deg). Last the bone-only information on the CT image did not show convergency property to the correct registration. 相似文献