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排序方式: 共有594条查询结果,搜索用时 15 毫秒
41.
OBJECTIVE: Anthropologists with an interest in American Indian alcohol use have long held that how native people drink has been conditioned by aspects of the social organization of their societies prior to the disruptive influences of European colonialism. Our goal in this article was to explicitly test the importance of these factors in four contemporary American Indian cultural groups. METHOD: Using data on adolescent alcohol use drawn from the first full wave of the longitudinal Voices of Indian Teens Project (N = 1,651, 51% female), we tested whether patterns of quantity-frequency of alcohol use and the negative consequences of alcohol use predicted by social organzational variables were found among contemporary adolescents and, subsequently, whether these differences persisted when other, more proximal, variables were included. RESULTS: Cultural differences appeared to account for a small percentage of the variance in both quantity-frequency of alcohol use and negative consequences in the initial steps of our analyses, but the pattern in these data was not consistent with the predictions of existing theories regarding aboriginal social organization. Moreover, these cultural differences were no longer significant in the final step of our analyses, suggesting that the cultural differences that did exist were better explained by other factors, at least among these adolescents. CONCLUSIONS: Although these analyses did not indicate that culture was irrelevant in understanding adolescent alcohol use in American Indian communities, classic formulations of these effects were of limited utility in understanding the experiences of contemporary American Indian adolescents. 相似文献
42.
Beals RK 《Clinical orthopaedics and related research》2003,(406):109-115
Radiographic and clinical evaluation was done on 12 members of a kindred that included members with hip dislocation. Acetabular dysplasia was found in several members who did not have dislocation. This supports the concept that acetabular dysplasia is inherited and acts as a precursor to dislocation. Identification of infants with primary acetabular dysplasia may allow measures to prevent dislocation. 相似文献
43.
Van Bergeyk A Stotler W Beals T Manoli A 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2003,24(10):765-770
BACKGROUND: Osteonecrosis of the talar body is a challenging problem for both patient and surgeon. One reconstruction option is an arthrodesis of the tibia to the talar neck, as described by Blair, which has the theoretical advantages of salvaging some hindfoot height and motion of the subtalar joint. A few case series have been published describing outcome after modified Blair fusions, none with validated functional outcomes. The purpose of this article is to describe a modification of Blair's original technique, and report the functional outcomes in a series of patients undergoing this procedure. METHOD: A retrospective review of seven patients with talar osteonecrosis undergoing modified Blair tibiotalar arthrodesis was performed. The median patient age was 51 (range, 39-78). Median follow-up was 20 months (range, 12-112). Two patients required a repeat procedure for delayed/nonunion, with subsequent uneventful union. In all patients the procedure included compression screw fixation of the talar head to the anterior distal tibia, with the two repeat procedures and the most recent patient having an additional anterior compression plate and bone graft. Functional outcome measures using both the AOFAS ankle-hindfoot score and the SF-36 global health outcome measure were obtained at latest follow-up. In addition, radiographic assessment of bone union and time to union was determined. RESULTS: Median SF-36 physical and mental component scores were 46 and 61, respectively. The median AOFAS ankle-hindfoot score was 67 out of 100. Median visual analog scales for postoperative pain and function were 7.1 and 6.0 respectively, out of a best possible score of 10. CONCLUSION: Functional outcome scores after modified Blair arthrodesis are lower than similar scores after conventional tibiotalar fusion, and much lower than "normal" values; however, the procedure has similar, if not lower, complication rates to alternative complex hindfoot reconstructions, and this procedure is a valuable alternative in the management of talar osteonecrosis with arthrosis. 相似文献
44.
The Hajdu-Cheney syndrome includes short stature, characteristic facies, and a slowly progressive skeletal dysplasia which affects skull, spine, and long bones. Two patients with this syndrome are presented. In the first patient the most distinctive skeletal feature, acro-osteolysis, was shown to be absent at age 6 years but was present at age 11 years. Diagnosis was made in the second case in the absence of acroosteolysis because of otherwise typical findings. Abnormalities affecting vision, hearing, and dentition occur and these, along with the other characteristic physical and radiographic features of the syndrome, should enable diagnosis prior to the onset of acro-osteolysis. 相似文献
45.
Y Shenker M D Gross R J Grekin S G Rosen J A Sanfield B Shapiro B Samuels W Strodel N W Thompson T F Beals 《Journal of endocrinological investigation》1986,9(2):115-120
I-131-6 beta-iodomethylnorcholesterol (NP-59) was used to localize mineralocorticoid-secreting adrenocortical carcinomas in two patients and functioning metastases in a third patient studied after the removal of the primary tumor. The presence of sufficient NP-59 activity within these lesions for discernable imaging is unusual and would not have been expected based on previous experience with other functioning and nonfunctioning carcinomas of the adrenal cortex. These cases serve to illustrate the variable spectrum of iodocholesterol uptake into adrenocortical malignancies and suggest that scintigraphic studies, preoperatively for localization and postoperatively to confirm the presence of recurrence or metastases, might be useful to identify and characterize these rare neoplasms. 相似文献
46.
47.
S E Fligiel T F Beals D P Tashkin M G Paule A C Scallet S F Ali J R Bailey W Slikker 《Pharmacology, biochemistry, and behavior》1991,40(3):637-642
As part of a large multidisciplinary study, we examined lungs from 24 periadolescent male rhesus monkeys that were sacrificed seven months after daily marijuana smoke inhalation of 12 months duration. Animals were divided into four exposure groups: A) high-dose (one marijuana cigarette 7 days/week), B) low-dose (one marijuana cigarette 2 days/week and sham smoke 5 days/week), C) placebo (one extracted marijuana cigarette 7 days/week), and D) sham (sham smoke 7 days/week). Lungs, removed intact, were formalin inflated, sectioned and examined. Several pathological alterations, including alveolitis, alveolar cell hyperplasia and granulomatous inflammation, were found with higher frequency in all cigarette-smoking groups. Other alterations, such as bronchiolitis, bronchiolar squamous metaplasia and interstitial fibrosis, were found most frequently in the marijuana-smoking groups. Alveolar cell hyperplasia with focal atypia was seen only in the marijuana-smoking animals. These changes represent mostly early alterations of small airways. Additional follow-up studies are needed to determine their long-term prognostic significance. 相似文献
48.
Ultraviolet irradiation of blood prevents transfusion-induced sensitization and marrow graft rejection in dogs 总被引:1,自引:1,他引:0
In a canine model using DLA-identical littermate pairs, we have shown that a regimen of three transfusions of donor blood given 24, 17, and 10 days before transplant uniformly leads to marrow graft rejection, presumably due to sensitization to minor (non-DLA) histocompatibility antigens. Untransfused dogs uniformly achieve sustained engraftment. In the present study, we investigated whether the exposure of blood to ultraviolet (UV) light (220-300 nm) prior to transfusion prevented sensitization of the recipient and allowed for successful marrow engraftment. Ten dogs were each given three pretransplant transfusions from the marrow donor. Each transfusion consisted of 50 mL of whole blood exposed in vitro to UV light for a total of 1.35 J/cm2. All ten dogs achieved engraftment. In contrast, all four dogs that had received sham-exposed transfusions rejected their grafts. In vitro studies revealed that although cell viability was not affected, leukocytes contained in UV-exposed blood were unable to function as stimulator cells in mixed leukocyte cultures or as accessory cells in mitogen- stimulated cultures. These data are consistent with the hypothesis that accessory cells are involved in transfusion-induced sensitization. We conclude that in vitro exposure of blood to UV light before transfusion prevents sensitization and allows for subsequent marrow engraftment. 相似文献
49.
50.
Effect of angioplasty-induced endothelial denudation compared with medial injury on regional coronary blood flow 总被引:1,自引:0,他引:1
E R Bates M J McGillem T F Beals S F DeBoe J K Mikelson G B Mancini R A Vogel 《Circulation》1987,76(3):710-716
To determine the effect of angioplasty-induced arterial injury on regional coronary blood flow, resting and postocclusion reactive hyperemic flows were measured in the left anterior descending (LAD) and circumflex (LCx) coronary arteries of 32 dogs after one of four interventions in the LAD with a balloon angioplasty catheter: group A, no injury; group B, endothelial denudation; group C, medial injury; group D, pretreatment with 325 mg of aspirin 2 hr before medial injury. Resting flows did not change in any group. In group C, hyperemic flow decreased in both the LAD and LCx by 15% to 20% (p less than .001) over 30 to 90 min, suggesting that a circulating substance changed coronary resistance. Histologic and ultrastructural studies of the LADs demonstrated an intact endothelial cell layer in group A, endothelial disruption with a few adherent platelets in group B, medial injury with a dense layer of adherent platelets in group C, and medial injury with a few adherent platelets in group D. Thus endothelial denudation results in relatively mild platelet deposition and no change in resting or hyperemic coronary blood flow. In contrast, medial injury results in relatively marked platelet deposition and a significant decrease in hyperemic flow, both of which are prevented by platelet inhibition with aspirin. 相似文献