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991.
C P Crum Y S Fu R U Levine R M Richart D E Townsend C M Fenoglio 《American journal of obstetrics and gynecology》1982,144(1):77-83
We reviewed 65 intraepithelial lesions of the vulva and distal vagina and compared the presence of koilocytosis, abnormal mitoses, and parabasal or basal nuclear enlargement with DNA microspectrophotometric distribution patterns and the presence of human papillomavirus antigen as determined by immunoperoxidase. Abnormal mitoses and cytologically atypical nuclear enlargement were specific predictors of aneuploidy and were reliable for distinguishing vulvar intraepithelial neoplasia (VIN) from condylomas. Koilocytosis was present in 100% of condylomas and 71% of aneuploid (VIN) lesions, but there were qualitative and quantitative differences in the distribution of koilocytic cells in the two classes of lesions. On the basis of these findings, criteria for distinguishing between VIN and condyloma are proposed. 相似文献
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993.
David V. Viola Erin A. Mordecai Alejandra G. Jaramillo Seeta A. Sistla Lindsey K. Albertson J. Stephen Gosnell Bradley J. Cardinale Jonathan M. Levine 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(40):17217-17222
Ecologists have long observed that consumers can maintain species diversity in communities of their prey. Many theories of how consumers mediate diversity invoke a tradeoff between species’ competitive ability and their ability to withstand predation. Under this constraint, the best competitors are also most susceptible to consumers, preventing them from excluding other species. However, empirical evidence for competition–defense tradeoffs is limited and, as such, the mechanisms by which consumers regulate diversity remain uncertain. We performed a meta-analysis of 36 studies to evaluate the prevalence of the competition–defense tradeoff and its role in maintaining diversity in plant communities. We quantified species’ responses to experimental resource addition and consumer removal as estimates of competitive ability and resistance to consumers, respectively. With this analysis, we found mixed empirical evidence for a competition–defense tradeoff; in fact, competitive ability tended to be weakly positively correlated with defense overall. However, when present, negative relationships between competitive ability and defense influenced species diversity in the manner predicted by theory. In the minority of communities for which a tradeoff was detected, species evenness was higher, and resource addition and consumer removal reduced diversity. Our analysis reframes the commonly held notion that consumers structure plant communities through a competition–defense tradeoff. Such a tradeoff can maintain diversity when present, but negative correlations between competitive ability and defense were less common than is often assumed. In this respect, this study supports an emerging theoretical paradigm in which predation interacts with competition to both enhance and reduce species diversity. 相似文献
994.
Adam C Levine Joseph Becker Suzanne Lippert Stephanie Rosborough Kris Arnold 《Academic emergency medicine》2008,15(9):860-865
The subspecialty of international emergency medicine (IEM) continues to grow within the United States, just as the specialty of emergency medicine (EM) continues to spread to both developed and developing countries around the world. One of the greatest obstacles, however, faced by IEM researchers and practitioners alike, remains the lack of a high-quality, consolidated, and easily accessible evidence-base of literature. In response to this perceived need, members of the Emergency Medicine Resident Association (EMRA) International Emergency Medicine Committee, in conjunction with members of the Society for Academic Emergency Medicine (SAEM) International Health Interest Group, have embarked on the task of creating a recurring review of IEM literature. This publication represents the third annual review, covering the top 30 IEM research articles published in 2007. Articles were selected for the review according to explicit, predetermined criteria that included both methodologic quality and perceived impact of the research. It is hoped that this annual review will act as a forum for disseminating best practices, while also stimulating further research in the field of IEM. 相似文献
995.
David B. Levine M.D. 《HSS journal》2008,4(1):1-9
In January 1925, the Board of Managers of the New York Society for the Relief of the Ruptured and Crippled appointed William Bradley Coley, M.D., age 63, Surgeon-in-Chief of the Hospital for the Ruptured and Crippled (R & C) to succeed Virgil P. Gibney who submitted his resignation the month before. It would be the first time a general surgeon held that position at the oldest orthopedic hospital in the nation, now known as Hospital for Special Surgery (HSS). Coley had been on staff for 36 years and was world famous for introducing use of toxins to treat malignant tumors, particularly sarcomas. A graduate of Yale College and Harvard Medical College, Coley interned at New York Hospital and was appointed, soon after, to the staff of the New York Cancer Hospital (now Memorial Sloan Kettering Cancer Center) located at that time at 106th Street on the West Side of New York. With his mentor Dr. William Bull, Coley perfected the surgical treatment of hernias at R & C. He was instrumental in raising funds for his alma maters, Yale, Harvard and Memorial Hospital. His crusade in immunology as a method of treatment for malignant tumors later fell out of acceptance in the medical establishment. After his death in 1936, an attempt to revive interest in use of immunotherapy for inoperable malignancies was carried out by his daughter, Helen Coley Nauts, who pursued this objective until her death at age 93 in 2000. Coley's health deteriorated in his later years, and in 1933, he resigned as chief of Bone Tumors at Memorial Hospital and Surgeon-in-Chief at R & C, being succeeded at Ruptured and Crippled as Surgeon-in-Chief by Dr. Eugene H. Pool. William Bradley Coley died of intestinal infarction in 1936 and was buried in Sharon, Connecticut. 相似文献
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998.
Primary hyperparathyroidism (PHPT) is a common endocrine disorder in adults in whom the typical presentation is incidentally discovered as asymptomatic hypercalcemia. PHPT is much less common in children and adolescents, but has greater morbidity in this age group, as most young patients with PHPT will have symptomatic hypercalcemia or complications such as kidney stones, abdominal pain, and skeletal fragility. An important feature of PHPT in younger patients is the relatively high prevalence of germline inactivating mutations of the CASR gene, which encodes the calcium-sensing receptor. Biallelic CASR mutations cause neonatal severe hyperparathyroidism, a life-threatening condition that presents within days of life with marked hypercalcemia, respiratory distress, failure to thrive, and skeletal demineralization. By contrast, more common heterozygous CASR mutations are generally associated with a benign variant of PHPT termed familial hypocalciuric hypercalcemia. Appropriate management of PHPT in children and adolescents requires distinction between familial hypocalciuric hypercalcemia, which generally requires no specific treatment, and other forms of PHPT that are best treated by parathyroidectomy. 相似文献
999.
1000.