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51.
S J Williams C W Tyler L Clark L Coleman P Curran 《American journal of preventive medicine》1988,4(4):231-238
We provide 1985 estimates of the work force of epidemiologists in the United States, the number of graduates from training programs in epidemiology, and a projection of the future need for these health professionals. Our methods included a search of mailing lists from professional organizations, mail contact with graduate training programs, telephone interviews with experts, and a review of job announcements in professional journals. The study indicates that the current work force of epidemiologists in the United States is estimated to include 4,600 persons, more than half of whom are physicians; most epidemiologists are located in either a state with a major federal public health agency or one with a large population; and programs in epidemiology graduate an average of 475 persons with one or two years of master's level education and approximately 80 with doctoral-level education each year. After considering the factors that influence the supply of epidemiologists, we project a substantial need for more epidemiologists in the future than current sources will provide. 相似文献
52.
Hyperoxaluria may result in diffuse deposition of calcium oxalate crystals in multiple organs. A patient with primary hyperoxaluria presented with peripheral ischemia on this basis. Computed tomography clarified the diagnosis and helped to direct the appropriate management. 相似文献
53.
Preliminary results are presented for a general population-based cancer registry in Setif, Algeria, for 1986-88. Standardised incidence rates for all sites, excluding non-melanoma skin cancer, are 70.1 for men and 59.9 for women: these rates are lower than those reported for most populations. The most frequent cancers are lung, stomach and liver in men, and cervix, liver and breast in women. Nasopharyngeal carcinoma is frequent in both sexes. Incidence of cancers of the gallbladder and extrahepatic bile ducts in women appears particularly high. These results represent the first detailed incidence data for all cancers in an Algerian population. 相似文献
54.
Chronic bullous disease of childhood--another cause for potential misdiagnosis of sexual abuse? 总被引:1,自引:0,他引:1
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There have been several reports of unusual skin conditions producing genital lesions that can be mistaken for sexual abuse. We report on another unusual skin condition, well known to dermatologists, that can again lead to potential misdiagnosis of sexual abuse. 相似文献
55.
Oscillatory motion of the normal cervical spinal cord 总被引:2,自引:0,他引:2
56.
Periosteal Ewing sarcoma 总被引:3,自引:0,他引:3
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59.
In a prospective, randomized study of insemination with donor semen,
intracervical insemination by straw was compared with insemination using a
cervical cap with an intracervical reservoir. A total of 91 patients
completed 486 treatment cycles. There were no significant differences in
age, parity, indication for insemination by donor, or method of cycle
monitoring between women who became pregnant and those who did not conceive
with either insemination method. In 236 standard intracervical insemination
cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients
conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude
pregnancy rates and the cumulative pregnancy rates calculated by the
Kaplan-Meier life-table method were significantly different (chi(2)-test, P
< 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates
in artificial insemination with cryopreserved donor semen may be improved
by the use of a cervical cap when compared to cervical insemination by
straw. The use of the cervical cap may prolong the exposure of the
spermatozoa to the cervical mucus and prevent the backflow of semen into
the vagina.
相似文献
60.