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11.
F Ribeiro-Dias M Russo FR Nascimento JA Barbuto J Timenetsky S Jancar 《Canadian Metallurgical Quarterly》1998,31(11):1425-1428
We describe a collective episode of psychogenic illness in an indigenous group (Embera) of Colombia, geographically isolated from its native homeland and surrounded by non-indigenous settlers. The condition, which affected three young adult men and six adolescent women, was attributed by them to a spell (maleficio). It was designated as ataques de locura (madness attacks) according to their traditional medical system; and as a conversive disorder with dissociative features by psychiatrists. Different therapeutic approaches, including antipsychotic medication, religious healers and traditional herbal remedies were unsuccessful. Contact with shamans of the same ethnic origin, on the other hand, proved to be an effective way of dealing with the symptoms. We interpret the situation as an expression of psychosocial stress secondary to cultural change. This medical problem bears close resemblance to other specific culture-bound syndromes such as ataques de nervios or possession syndromes and gives clues to ways of dealing with psychogenic expressions of cultural stress. 相似文献
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We report here an experience with five patients, aged 58 to 70, suffering gangrene of the left colon after spontaneous inferior mesenteric artery occlusion. All cases were the result of arteriosclerosis; in two, small aortic aneurysms were present and might have been responsible for emboli to the inferior mesenteric artery. The dead bowel was resected in all patients; three patients survived. No primary anastomoses were done and they are not recommended. Because ligation of the patent inferior mesenteric artery has been done so often without ill effects during aortic surgery, the collateral circulation to the left colon can be considered excellent. Gangrene is therefore rare and requires major interference with collateral circulation by emboli or arteriosclerotic occlusion. The clinical symptoms and signs may be confusing. 相似文献
14.
Venous thromboembolism is a leading cause of death and morbidity after extended surgery for early malignancies of the cervix and uterus. Two hundred eighty-one patients who underwent such surgery were retrospectively evaluated for associated risk factors, the incidence of clinically significant thromboembolic complications, and prophylactic value of low-dose heparin and antiembolism stockings. Significant thromboemboli were encountered in 7.8% of patients postoperatively and accounted for the only 4 postoperative deaths. Forty-five percent of patients who developed thromboemboli did so after discharge from the hospital. The preoperative risk factors found to be associated with thromboembolism, in order of statistical significance, were weight in excess of 85.5 kg, advanced clinical stage of malignancy, and radiation therapy within 6 weeks of the operative procedure. Low-dose heparin therapy and the use of antiembolism stockings as preventative measures did not appear to reduce the incidence of thromboembolic complications. A prospective study will be necessary to evaluate definitely the effectiveness of various therapeutic modalities on thromboembolism in gynecologic oncology patients. 相似文献
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To describe the contribution of garden dormice to the epizootiology of Lyme disease, we compared their reservoir capacity for these pathogens to that of other sympatric hosts. Garden dormice are trapped most abundantly during early spring and again during midsummer, when their offspring forage. They are closely associated with moist forests. Garden dormice serve as hosts to nymphal ticks far more frequently than do other small mammals. Spirochetal infection is most prevalent in dormice, and many more larval ticks acquire infection in the course of feeding on these than on other rodents in the study site. Mature dormice appear to contribute more infections to the vector population than juveniles do. Replete larval ticks generally detach while their dormouse hosts remain within their nests. The population of garden dormice contributes five- to sevenfold more infections to the vector population than the mouse population does. Their competence, nymphal feeding density, and preference for a tick-permissive habitat combine to favor garden dormice over other putative reservoir hosts of Lyme disease spirochetes. 相似文献
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J García-Arumí R Pascual MJ Fonseca FR Isart R Casaroli C Mateo B Corcostegui 《Canadian Metallurgical Quarterly》1997,211(6):344-350
Relationships from benefits-costs analyses in radiography are presented. The impact of several factors (equipment, frequency of examinations, ...) on the planning of a department and special financial aspects, e.g., leasing of equipment, are discussed. The cost relationships of conventional versus digital radiography are demonstrated for the example of a 1000-bed hospital. 相似文献
17.
Preservation of protein fluorescence in embedded human dendritic cells for targeted 3D light and electron microscopy 下载免费PDF全文
K. HÖHN J. FUCHS A. FRÖBER R. KIRMSE B. GLASS M. ANDERS‐ÖSSWEIN P. WALTHER H.‐G. KRÄUSSLICH C. DIETRICH 《Journal of microscopy》2015,259(2):121-128
In this study, we present a correlative microscopy workflow to combine detailed 3D fluorescence light microscopy data with ultrastructural information gained by 3D focused ion beam assisted scanning electron microscopy. The workflow is based on an optimized high pressure freezing/freeze substitution protocol that preserves good ultrastructural detail along with retaining the fluorescence signal in the resin embedded specimens. Consequently, cellular structures of interest can readily be identified and imaged by state of the art 3D confocal fluorescence microscopy and are precisely referenced with respect to an imprinted coordinate system on the surface of the resin block. This allows precise guidance of the focused ion beam assisted scanning electron microscopy and limits the volume to be imaged to the structure of interest. This, in turn, minimizes the total acquisition time necessary to conduct the time consuming ultrastructural scanning electron microscope imaging while eliminating the risk to miss parts of the target structure. We illustrate the value of this workflow for targeting virus compartments, which are formed in HIV‐pulsed mature human dendritic cells. 相似文献
18.
采用冷却速率为0.01~3K/s的差示扫描量热法(DSC)和冷却速率更高的淬火膨胀法研究铸态Al-7Si-0.3Mg合金淬火的析出行为。在合金冷却的过程中发生了两种析出反应,高温反应开始于淬火起始温度540℃,低温反应始于400℃左右。3K/s的淬火冷却速率已经显著抑制淬火过程中相的析出。合金T6态的硬度随着淬火速率的增快而增加,这是由合金过饱和固溶度增加而导致的。通过膨胀实验和硬度实验的结果可以估计临界冷却速率大约为60K/s。通过光学显微镜观察淬火态的铸态Al-7Si-0.3Mg合金的显微组织。结果表明:根据淬火冷却速率的不同合金的显微组织由铝一硅共晶组织、铝固溶体枝晶及枝晶间的析出相组成。 相似文献
19.
FR Margolin 《Canadian Metallurgical Quarterly》1992,1(1):1-10
The capability of high-quality mammography to discover early, preclinical breast cancer has demanded the development of a new relationship between radiologists, surgeons, and pathologists. It is only through mutual understanding and appreciation of the technical requirements and interpretive difficulties involved in the successful identification, preoperative localization, and excision of these lesions that the full benefits of this method of early cancer detection can be brought to all of our patients. 相似文献
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