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31.
Objective : To determine antibody levels to the Australian manufactured combined diphtheria, tetanus and pertussis (DTP) vaccine (Triple Antigen, CSL Ltd) in infante before and after their primary immunization course.
Methodology : Serosurvey (antibody prevalence study) in two groups: infants aged 5-9 weeks who had not received any immunizations ( n = 25), and infants aged 7-10 months who had received two ( n = 25) or three immunizations ( n = 57) with DTP, sampled from infants attending the Royal Children's Hospital, Melbourne, either as inpatients or outpatients between February and April 1993. The immunization history for each infant was determined from hospital records, the parent-held child health record, or the local council or family doctor who immunized the infant.
Results : Enzyme immunoassay (EIA) of antibodies to diphtheria and tetanus showed all infants to have adequate protective levels after two or three vaccinations (£0.01 IU/mL). All subjects who had received all three DTP vaccinations had detectable antibody to at least one pertussis antigen. Antibodies to the pertussis antigens filamentous haemagglutinin and pertussigen (pertussis toxin) were comparable to levels determined for whole cell pertussis vaccines used elsewhere in the world. EIA-determined antibodies to pertussis agglutinogen type 2 and agglutinogen type 3 showed substantially higher geometric mean titres when results for pre-immunization and post-immunization subjects were compared.
Conclusions : These data show that the Australian manufactured DTP vaccine has immunogenic properties similar to those of vaccines used elsewhere, and that antibody concentrations following immunization are at levels consistent with efficacy.  相似文献   
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The Department of Preventive Medicine and Community Health at the State University of New York, Health Science Center at Brooklyn (SUNY, HSCB) instituted an eight-week third world international health elective for fourth year medical students in 1980. Since that time, ninety students have participated. The purposes of this elective are to provide fourth year medical students with an opportunity to observe and study the structure and functions of a health care delivery system in a third world country, to provide medical service, and to have a crosscultural experience. The emphasis in this elective is on public health, preventive medicine, and primary care. There is a high level of student competition for this elective, with 46.9% of applicants having been accepted over a fifteen-year period. Although women comprise 40% of the average medical school class, they represent 50% of participants in this elective program. The percentage of African-American and Hispanic students has been 20%. These two minority groups represented from 8% to 10% of the student body during the period under study. Careful screening, including an examination of academic records and personal interviews, has resulted in the selection of highly motivated, adaptable, and dedicated students who have performed well at overseas sites. Student satisfaction levels with this elective are extremely high, with most rating it the best experience of their medical school years. Students undergo extensive preparation prior to going overseas. This covers issues related to individual health and safety, travel and lodging, and the nature of the host country culture, health care system, and assignment site. Our students are especially experienced at cross-cultural understanding because of the unusual diversity of the patients they treat in Brooklyn, and the ethnic diversity of local hospital staffs and the medical school class. This Brooklyn experience in cross-cultural understanding has been cited by many participants as having been the best preparation for functioning in a foreign culture. The Alumni Fund of the College of Medicine has strongly and consistently supported this elective both with philosophical commitment and financial grants to help defray travel costs. This type of support is unusual among medical schools in New York City. Overseas preceptors have willingly given of their time and institutional resources to make these experiences available and meaningful for students.  相似文献   
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研究表明:肿瘤坏死因子(TNF)可剂量依赖地引起牛肺动脉内皮细胞乳酸脱氢酶释放率(LDH%)升高,促进中性粒细胞向内皮细胞粘附,并可抑制内皮细胞增殖和DNA合成。蛋白激酶C(PKC)抑制剂1-(5-异喹啉磺酰基)-2-甲基哌嗪(H-7)和槲皮素一方面可剂量依赖地抑制TNF对内皮细胞的直接损伤,另方面又可通过抑制TNF诱导的中性粒细胞对内皮细胞粘附增加,减轻TNF对内皮细胞的间接损伤作用,同时还可抑制TNF对内皮细胞增殖和DNA合成的影响,从而间接加强内皮细胞对损伤的自我修复。  相似文献   
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Sider  L; Davis  TM  Jr 《Radiology》1987,164(1):107-109
Computed tomography (CT)-guided biopsies of 20 patients with hilar masses were performed after non-diagnostic bronchoscopic examination. Bronchoscopy included washings, brushings, routine biopsy, and, in many cases, transbronchial biopsy. In all but one case (95%), biopsy with a 22-gauge needle permitted a cytologic diagnosis of malignancy. In 14 of the 19 cases (74%), a diagnosis of primary lung carcinoma involving the hili was made, and in the remaining five of the 19 (26%), metastatic hilar adenopathy from an extrathoracic primary tumor was identified. A pneumothorax rate consistent with our average rate for CT-guided biopsies (25%) was obtained, and only one patient required chest tube placement. In this series, CT-guided biopsies of hilar masses were more consistently successful in obtaining tissue for diagnosis than were bronchoscopic biopsies. Transthoracic needle aspiration biopsy may be the preferred initial diagnostic procedure in many patients with hilar masses.  相似文献   
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BACKGROUND: One of South Africa's principal tourist attractions is the opportunity to encounter Africa's large mammals in the wild. Attacks by these mammals can be exceptionally newsworthy with potentially deleterious effects on tourism. Little is known about the risk of injury and death caused by wild mammals to visitors to South Africa's nature reserves. The aim of this study was to determine the incidence of fatal and nonfatal attacks on tourists by wild mammals in South Africa and to ascertain avoidable factors, if any. METHODS: Commercial press records covering all South African Newspapers archived at the Independent Newspapers' central library were systematically reviewed for a 10-year period, January 1988 to December 1997 inclusive, to identify all deaths and injuries to domestic and international tourists resulting from encounters with wild mammals in South Africa. All of these incidents were analyzed to ascertain avoidable factors. RESULTS: During the review period seven tourists, including two students from Thailand and a German traveler, were killed by wild mammals in South Africa. Three of the four deaths ascribed to lions resulted from tourists carelessly approaching prides on foot in lion reserves. A judicial inquiry found that the management of a KwaZulu-Natal Reserve was culpable for the remaining death. Tourist ignorance of animal behavior and flagrant disregard of rules contributed to the two fatalities involving hippopotami. The unusual behavior manifested by the bull elephant responsible for the final death, resulted from discomfort caused by a dental problem to this pachyderm. During the same period there were 14 nonfatal attacks on tourists, including five by hippo, three by buffalo, two by rhino, and one each by a lion, leopard, zebra and musth elephant. Only the latter occurred while the visitor was in a motor vehicle. Tourist ethological naivete and failure to determine the experience of trail guides prior to travel, resulted in inadvertent agonistic behavior, unnecessary risk-taking and avoidable injury. CONCLUSIONS: This retrospective study has shown that attacks on tourists by wild mammals in South Africa are an uncommon cause of injury and death. Sensible precautions to minimize this risk include remaining in a secure motor vehicle or adequately fenced precincts while in the vicinity of large mammals, rigidly observing nature reserve instructions, never approaching animals that appear ill, malnourished, displaying aggressive behavior traits or female wild mammals with young, and demanding adequately trained and experienced game rangers when embarking on walking trails. Any behavior that might be construed as antagonistic and which could provoke an attack by large mammals should be avoided (e.g., driving directly at a lion). Visitors need to be informed of classic signs of aggression, in particular in elephants, which will allow timely avoidance measures to be taken. The risk-enhancing effect of excessive alcohol intake is undesirable in the game reserve setting, as is driving at high speed after dusk in areas where hippos graze. Local advice on personal safety in wildlife reserves and the credentials of trail guides should be obtained from lodge or reserve management, tourism authorities or the travel industry prior to travel to game reserves.  相似文献   
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Carcinosarcomas are rare malignant biphasic tumours that contain intermingled carcinomatous and sarcomatous elements. Primary cutaneous carcinosarcomas (PCCS) are extremely rare. We present the 20th reported case and review the literature especially regarding histogenesis and clinical features such as diagnosis and management. PCCS resembles other non-melanocytic neoplasms of the skin. Diagnosis is obtained by primary excision with subsequent histologic and immunohistochemical examination. PCCS is a potentially lethal neoplasm, but radical surgery is successful in most cases.  相似文献   
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