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191.
Twenty patients, aged 4 months to 58 years, were evaluated for liver transplantation by duplex sonography, and 15 transplantations were completed; 42 postoperative examinations were performed. Sonographic findings were correlated with seven preoperative and five postoperative angiographic evaluations. Preoperative duplex US findings included tumors, portal vein occlusion, varices, biliary obstruction, and variant vascular anatomy. Postoperative findings included hepatic artery occlusion, portal vein occlusions (one with cavernous transformation), portal vein stenosis, biliary obstruction, intrahepatic and extrahepatic fluid collections, and air in the portal vein due to ischemic bowel. Use of angiography allowed confirmation of the vascular abnormalities and demonstrated evidence of rejection in patients with normal Doppler waveforms. Duplex sonography is a valuable portable technique for evaluating these patients and can be used in triage of patients requiring angiography. 相似文献
192.
Greenlee MW; Koessler M; Cornelissen FW; Mergner T 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(3):253-267
Visual discrimination and short-term recognition memory for computer-
generated random patterns were explored in 23 patients with a postsurgical
lesion in one of the cortical hemispheres. Their results are compared with
those of 23 age-matched volunteers. In a same- different forced-choice
discrimination task, d' and log beta (measures of sensitivity and bias), as
well as reaction time (RT) were determined. All participants viewed
patterns defined either by luminance contrast or isoluminant red-green
color contrast, the amplitude of which was adjusted to be 10 times the
respective detection threshold level. Block patterns consisting of a 6 x 6
matrix of light and dark (red and green) checks were randomly configured on
each presentation. They were presented in pairs, randomly in two visual
quadrants for a duration of 200 msec. Three presentation conditions were
used: simultaneous presentation of reference and test stimulus, sequential
presentation with a short delay (interstimulus interval, ISI = 3 s), and
sequential presentation with a long delay (ISI = 6 s). The results indicate
that patients with a lesion in the occipitotemporal cortex, the superior
temporal cortex and the frontal cortex were significantly impaired on both
luminance-contrast and color-contrast pattern discrimination. Patients with
damage in the anterior inferotemporal cortex showed no overall impairment.
The results suggest that performance in visual discrimination and
recognition memory tasks rely on distributed neural processes with more
than one neocortical location.
相似文献
193.
Two cycles of MOPP and radiotherapy: effective treatment for stage IIIA and IIIB Hodgkin's disease 总被引:1,自引:0,他引:1
F B Hagemeister L M Fuller W S Velasquez P McLaughlin J R Redman F Swan M A Rodriguez L North D Dixon K Silvermintz 《Annals of oncology》1991,2(1):25-31
Two cycles of MOPP (mechlorethamine, vincristine (Oncovin), procarbazine, prednisone) and radiotherapy were used to treat 197 patients with stage III Hodgkin's disease. Prior to 1980, radiotherapy was delivered to the mantle, abdomen and pelvis; thereafter, pelvic irradiation was deleted for patients with stage III1 disease. Complete remission rates for IIIA and IIIB presentations were 91% and 89%. The 10-year freedom from tumor mortality (FTM) rate for all patients was 81%; for IIIA, it was 87% and for IIIB, it was 72%. Results were not significantly affected by gender, age, pathology, or deletion of pelvic radiotherapy. However, a subgroup of 28 patients with a tumor burden that included pelvic disease who also had B symptoms was identified as having a poor prognosis. Their FTM was 43%, compared with 87% for all other patients combined (P = 0.002). Based on this analysis, we conclude that limited chemotherapy in combination with radiation therapy can yield results similar to programs that use more chemotherapy for all patients with IIIA disease and for most patients with stage IIIB. However, patients with tumor burdens which include pelvic disease and B symptoms require a different approach. 相似文献
194.
J F Redman 《Urology》1987,29(2):166-169
It is frequently stated that extravasation of urine after intrarenal surgery is deleterious to renal wound healing causing fibrosis or granulation tissue. A study using dogs was designed to test the hypothesis that the contact of urine with incised renal parenchyma may cause altered wound healing. This study showed that exposure of the renal parenchyma to extravasated urine from open collecting structures did not alter renal healing. 相似文献
195.
196.
197.
Margaret Grigg M.Med.Sci. Jenny Bowman Ph.D. Sally Redman Ph.D. 《Preventive medicine》1996,25(6):748-756
Background.Dissatisfaction with body weight and the use of unhealthy weight reduction practices have been reported among adolescent females. There is a need for methodologically rigorous studies using large representative samples of adolescent females to accurately assess the prevalence of these behaviors and attitudes.Methods.Eight hundred sixty-nine Australian school girls ages 14–16 years were administered a self-report questionnaire to determine the prevalence of disordered eating behaviors, unhealthy dieting practices, and distorted body image. Anthropometric (height and weight) data were collected on each of these adolescent females.Results.The prevalences of disordered eating, unhealthy dieting, and distorted body image were 33, 57, and 12%, respectively. Over one-third (36%) of the total sample had used at least one “extreme” dieting method in the past month, i.e., “crash” dieting, fasting, slimming tablets, diuretics, laxatives, and/or cigarettes to lose weight. Of the total sample, 77% wanted to lose weight and 51% had tried to lose weight in the past month. Motivating factors for disordered eating and unhealthy dieting behaviors were peer pressure, media pressure, and the perception that extreme dieting strategies were harmless.Conclusion.The prevalence of disordered eating and dieting behaviors among adolescent females shown by this study suggests the need for preventive programs encouraging appropriate eating and dieting behaviors. 相似文献
198.
199.
We examined differences in approaches to HIV-related infection control practices in two university teaching hospitals in the United States and Nigeria. Health care workers (n = 202 in Nigeria and 186 in the USA) responded to a previously validated measure of infection control practices. There were significant differences in the estimated probability of treating a person with HIV disease (higher in USA), and a greater probability of peer ridicule as a way of enforcing group norms on infection control in Nigeria. Peer enforcement of norms was significantly lower in the USA. In both countries, more precautions would be taken if it was known that the patient was HIV infected. Infection control practices were more likely to be followed in the USA compared with Nigeria if they were praised for this activity, if appropriate facilities (sharps containers, gloves, etc.) were nearby, and if they felt that infection control procedures were effective. These data point to the importance of normative social pressures in Nigeria and of knowing the patient is HIV infected in the USA and feeling that infection control procedures are effective ways of avoiding occupational HIV infection. The role of normative pressures and assumptions about HIV infection status as well as cues and availability of facilities for infection control appear to differ between these health care workers in Nigeria and the USA. 相似文献
200.
Diagnostic tests for choreoacanthocytosis. 总被引:2,自引:0,他引:2
T E Feinberg C D Cianci J S Morrow J C Pehta C M Redman T Huima W J Koroshetz 《Neurology》1991,41(7):1000-1006
Two patients with striatal atrophy and a clinical syndrome consistent with choreoacanthocytosis had normal dried blood smears but their red cells demonstrated an abnormal sensitivity to various conditions known to promote discocyte-echinocyte transformation. Dilution in normal saline, in vitro aging, and contact with glass caused a great proportion of these patients' red cells to develop multiple spiny or rounded projections. Under identical conditions, such shape changes did not occur in normal patients or in those with Huntington's disease. Scanning electron microscopy showed that the age-induced increase in acanthocytic-appearing cells could be reversed with chlorpromazine. These data suggest that the red cells from these patients with striatal degeneration are deficient in their ability to preserve normal shape in the face of echinocytic stress and that this observation has diagnostic and, possibly, pathophysiologic significance. 相似文献