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991.
Motorcycle riding is a significant cause of serious injuries to young males. Little is known about the psychological and social characteristics of these riders, despite such knowledge being potentially important for the targeting of appropriate injury prevention interventions. Using problem-behaviour theory to broadly guide and structure the research, the present study focused on identifying predictors of motorcycle riding. Previous research investigating differences between riders and non-riders has tended to be inconclusive, methodologically limited, and lacking in explicit theoretical foundations. The present research was based on the birth cohort enrolled in the Dunedin Multidisciplinary Health and Development Study (DMHDS), a comprehensive New Zealand longitudinal study of health, development, attitudes, and behaviours. Logistic regression models were built using prior measures of health risk behaviour, other psychological and social factors, and motorcycle riding history as potential predictors of any motorcycle use at the age of 18 years. The strongest predictors were early motorcycle riding, including illegal on-road driving at age 13 (OR 4.0; 95% CI 1.7, 9.1), below average reading skills (OR 2.4; 95% CI 1.3, 4.6) and fighting in a public place at age 15 (OR 2.9; 95% CI 1.2, 6.9). It was of particular interest that this profile tended to fit less well those subgroups of riders with greatest exposure to on-road motorcycle driving. Although based on small numbers, this finding was consistent with earlier cross-sectional research that linked casual and unlicensed driving with less protective motorcycling opinions and behaviours. Some implications for injury prevention and public policies regarding motorcycling are discussed. In particular, stricter enforcement of present licensing regulations and stronger penalties for their violation could help to reduce the number of less responsible riders.  相似文献   
992.
Injury resulting from participation in sporting and physical recreational activities is a major contributor to the overall incidence of injury in the developed world. If sports injuries are to be reduced, a comprehensive approach must be taken to define the nature and magnitude of the problem, to establish models of relationships between risk factors, protective factors and injury experience, and to address injury through well designed intervention and evaluation programmes. The Rugby Injury and Performance Project (RIPP) is a prospective cohort study designed to examine the risk and protective factors for rugby injury. Data were collected on potential risk and protective factors from the RIPP cohort pre-season. Data on exposure to rugby, injury events and medical treatments were collected from the players each week during the season through telephone interviews. Pre-season measures were repeated post-season. A key feature of the design was that data were collected on both injured and non-injured players, allowing a longitudinal comparison of the injury experience of players with and without the factors of interest. A wealth of information was collected on each cohort member during the pre-season interview. A contact rate of 90% was achieved during the weekly follow-up phase. Post-season questionnaires were completed by 76% of the players and 88% of the coaches. Recommendations are made for the use of this methodology by other researchers and future directions for RIPP are described.  相似文献   
993.
Sponsored by the US Department of State and the US Army Pacific as part of a Medical Readiness Training Exercise, 17 physicians from Tripler Army Medical Center traveled to Outer Mongolia during September 1995 to examine the practice of medicine in the country. The obstetrical care observed was delivered at Third Women's Hospital in Ulanbataar. Prenatal care in Mongolia is provided mainly by family physicians, with the family doctor visiting each pregnant patient every month for the first 5 months, increasing to weekly visits at 7 months. The patient is taken to an obstetrical or women's and children's hospital when she reaches term or goes into labor. The staff at Third Women's Hospital deliver approximately 2000 babies annually and perform approximately 1000 pregnancy terminations through sharp curettage. The cesarean section rate is reported to be 10%. The hospital has no laboratory or X-ray capability, but can send out for such tests on rare occasions. During labor, patients are fully ambulatory on an as-needed basis. Fetal monitoring is not routinely available, except for occasional auscultation, patients in labor were not given IV fluid, delivery rooms were bleak and with only antiquated equipment, lighting was poor, and gloves were reused until they were too tattered for reuse. The authors discuss their experience with 3 cesarean sections and 1 ectopic pregnancy performed while in the country.  相似文献   
994.
Earlier studies by other investigators have shown that S-adenosylmethionine (SAM) has the capacity to attenuate liver injury in experimental animals. In a recent study in this laboratory, it was shown that when supplemental dietary betaine was given to control and ethanol-fed rats at the level of 0.50% (W/V), SAM levels were doubled in the livers of control animals and increased fivefold in livers of ethanol-fed rats. The increased levels of SAM in the livers of ethanol-fed animals protected the livers from fatty infiltration due to ethanol feeding. In this study, an attempt was made to determine the minimum level of dietary betaine that protects against the fatty infiltration. Levels of betaine at 0.05%, 0.10%, 0.25%, and 0.50% in semiliquid control and alcohol diets were tested in rats for 30 days. When hepatic betaine, SAM, and triglyceride levels were determined, it was demonstrated that only the dietary level of betaine at 0.50% supplied enough hepatic betaine to generate the level of SAM that was required to protect against the alcoholic steatosis resulting from the dietary ethanol. These results suggest that betaine, when given in sufficient amounts, may be a promising therapeutic agent in the treatment of liver disease.  相似文献   
995.
Lumbosacral defects on 20 patients were covered with a perforator-based flap. Cutaneous perforators derived from the 9th and 10th intercostal arteries, the 4th lumbar artery, and multiple gluteal perforators that penetrate the gluteus maximus muscle were used as vascular pedicles. Minor complications occurred in five cases. Using this method, minimal morbidity of the donor site is expected because the gluteus maximus need not be sacrificed. Accordingly, perforator-based flaps are especially indicated for ambulatory patients, but for paraplegic patients as well. Even in the event of recurrence, another perforator-based or musculocutaneous flap can be elevated from the ipsilateral side because of the presence of multiple perforators in the lumbosacral and gluteal regions.  相似文献   
996.
Malignant rhabdoid tumor (MRT) is a rare, enigmatic childhood cancer characterized by extreme aggressiveness and resistance to chemotherapy. To understand better the origin of the tumor and the mechanisms by which it develops and resists treatment, five cell lines were established from patients presenting with MRT (two renal and three extrarenal tumors). All of the cell lines display the light microscopic and ultrastructural features, as well as the variable immunohistochemical profile, characteristic of MRT. All are capable of forming tumors in nude mice. Three of the cell lines have detectable abnormalities of chromosome 22: one a t(22, 22) unbalanced translocation and two others a loss of heterozygosity of polymerase chain reaction-based microsatellite markers. Northern blot analysis showed that overexpression of the c-myc message was a consistent characteristic of the five MRTs evaluated. Although mutations of the p53 gene were not detectable by sequence analysis, all of the cell lines showed nuclear accumulation of the p53 protein by an immunocytochemical analysis in a minority of the cells. This result suggests that dysfunction in a p53-dependent apoptotic pathway might play a role in the multiple drug resistance phenotype of these tumors.  相似文献   
997.
Four disease genes (NBCCS, ESS1, XPAC, FACC) map to 9q22.3-q31. A fine map of this region was produced by linkage and haplotype analysis using 12 DNA markers. The gene for nevoid basal cell carcinoma syndrome (NBCCS, Gorlin) has an important role in congenital malformations and carcinogenesis. Phase-known recombinants in a study of 133 meioses place NBCCS between (D9S12/D9S151) and D9S176. Haplotype analysis in a two-generation family suggests that NBCCS lies in a smaller interval of 2.6 cM centromeric to D9S287. These flanking markers will be useful clinically for gene tracking. Recombinants also map FACC (Fanconi anemia, group C) to the same region, between (D9S196/D9S197) and D9S287. The recombination rate between (D9S12/D9S151) and D9S53 in males is 8.3% and 13.2% in females, giving a sex-specific male:female ratio of 1:1.6 and a sex-averaged map distance of 10.4 cM. No double recombinants were detected, in agreement with the apparently complete level of interference predicted from the male chiasmata map.  相似文献   
998.
999.
A 53-yr-old woman with a history of hepatic cystadenoma 25 yr before presented with a simple hepatic cyst, which evolved over 9 yr into a complex cystadenoma with septations and internal bleeding. She was treated with a left hepatectomy. Review of the literature shows that hepatic cystadenomas, although rare, frequently can recur years later and have potential for malignant transformation. Histologic similarities of one variant with ovarian stroma raises interesting possibilities regarding the origin of these lesions. The best treatment results are obtained with radical excision.  相似文献   
1000.
We have previously reported on the secretion of a family of high Mr plasminogen activators (PAs) by a human lung cancer cell line [Harvey et al. (1991) Biochim. Biophys. Acta 1078, 360-368]. We have now extended these studies to several human cancer cell lines and a human embryonic lung cell line. In the present study with HPL-SK-1 lung cancer, A431 epidermoid cancer, ovarian carcinoma, and embryonic lung cell lines, we show that the 900- and the 660-kDa PAs are disulfide-bonded multiprotein oligomeric complexes. They are functionally and immunologically related to human urinary PA (uPA). Their size and PA activity are not destroyed by strong denaturants such as 8 M urea or 2% sodium dodecyl sulfate (SDS), suggesting that the uPA moiety is covalently associated with the rest of the molecule. It is only under strong denaturing conditions with 1.4 M beta-mercaptoethanol and 2% SDS that the uPA moiety could be released as a 21- to 23-kDa fragment along with two major polypeptide chains of 70 and 40 kDa, respectively. The presence of the uPA active center in the reduced PA660 was demonstrated by [3H]diisopropylphosphorofluoridate labeling and by Western blot using a monoclonal antibody to uPA B chain. N-terminal amino acid sequencing of the 70- and 40-kDa polypeptides, respectively, showed homology to the neural cell adhesion molecule and the beta chain of haptoglobin. A minor fragment of 18 kDa obtained under strong reduction conditions was also sequenced and shown to share homology with the alpha chain of haptoglobin. Western blot analysis of the reduced PAs with monoclonal antibody to the neural cell adhesion molecule and rabbit anti-haptoglobin confirmed the homologies obtained by the sequence data. Further, immobilized monoclonal antibodies to the neural cell adhesion molecule, uPA B chain, and rabbit anti-haptoglobin bound the multiprotein complexes with uPA activity, from A431, ovarian cancer, and embryonic lung cell lines. The bound material, after dissociation, exhibited PA activity that was inhibited by monoclonal antibody to the uPA B chain. These data suggest that in tumor and embryonal cell lines, in addition to proper folding and assembly of proteins by intramolecular disulfide bond formation in the endomembrane compartment, intermolecular disulfide bonds could also occur, producing multiprotein oligomers as in the present case. Formation of such oligomers may have a selective advantage for such cells in the focalization of proteolytic activity through the interaction of the neural cell adhesion molecule domain with the extracellular matrix and in immunosuppression of lymphocytes by the haptoglobin portion of the complex.  相似文献   
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