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991.
992.
A 27 year old female is described who had 46,XY chromosome complement, ambiguous external genitalia with elevated LH, slightly above normal FSH and low testosterone. Her plasma testosterone level increased 15-20 fold after HCG stimulation (5000 IU X 3). then returned to prestimulation level 3 months later. This was possibly due to the secretion of an abnormal LH molecule which is immunoreactive but biologically inactive in the human.  相似文献   
993.
In the cricket, Gryllus campestris, a branch of the nervus tegumentarius runs to the distal part of the optic lobe. This branch contains the axons of interommatidial hair receptors. The axon terminations extend forward into the trito- and deutocerebrum, and into the subesophageal- and prothoracic ganglia as shown with the cobalt sulfide staining technique. The possible relevance of these connections is discussed.  相似文献   
994.
Spontaneous regression of metastatic cancers occurs rarely and has been reported only once for pulmonary metastases from transitional cell carcinoma. Two cases of spontaneous complete regression of lung metastases from transitional cell carcinoma are presented. In one case, regression occurred after a course of radiation to the primary bladder cancer, but in the other patient, lung lesions disappeared without treatment to the primary or metastatic cancers. The factors that alter the tumor-host relationship to allow spontaneous regression of cancers are unknown, but observation of these phenomena may help reveal parameters that influence tumor progression in the majority of cancer patients.  相似文献   
995.
996.
In rat experiments a new silver chelate salt preparation is tested on scald wounds after standardized infection by Pseudomonas aeruginosa. 30% of the animals survive scalding and infection after treatment with the new cream. This percentage does not reach the gentamycin treated reference group (60%). After combining gentamycin and silver chelate salt in local therapy 75% of the animals survive. Combination of silver chelate salt and gentamycin seems to be a very successful local therapy of scald wounds.  相似文献   
997.
Hypotonic duodenography, duodenoscopy, and operative exploration were performed in an adult with double duodenal webs and symptoms suggesting gastric outlet obstruction. The spectrum of diagnostic features associated with this rare entity is described in this report.  相似文献   
998.
999.
This paper focuses on rough set models on two universes and reveals some new properties. A revised rough set model is proposed which provides a new selection of interval structures for uncertain reasoning using rough set theory and methods.  相似文献   
1000.
Initially recognized in 1982, acquired immunodeficiency syndrome (AIDS) has been the leading cause of death among young adults in the United States for much of this decade, and it has had a devastating impact on people in the developing world. It is estimated that 42 million people worldwide have been infected with human immunodeficiency virus (HIV), the virus that causes AIDS, and that almost 12 million people have died from AIDS-related diseases through 1997. Among these 12 million are 3 million children. Two thirds of the more than 30 million people with HIV or AIDS reside in sub-Saharan Africa. In the United States, 641,086 patients have been diagnosed with AIDS through 1997, and at least 385,000 have died. However, for the first time, new highly active antiretroviral therapies that include multiple drugs that attack the virus at several sites have slowed the progression from HIV to AIDS and from AIDS to death for those infected with HIV. The cumulative effect of these changes has been a reduction in both AIDS incident cases and AIDS deaths. Recent epidemiologic trends indicate that the proportion of AIDS incident cases and new HIV infections are increasing among women, African-Americans, and Hispanics, and the infections are more likely to be acquired through heterosexual transmission. The clinical management of HIV infection and AIDS has become increasingly complex in recent years. In addition to complete medical and social histories and physical examinations, hematologic, biochemical, serologic, and immunologic laboratory tests are required to predict the likelihood that patients will develop opportunistic infections and other complications related to HIV infection. Among the most important laboratory tests are measurements of HIV in plasma (viral load) in conjunction with peripheral blood CD4+ helper T lymphocyte counts. These tests are potent predictors of disease progression and their results have become markers for clinical response to therapy. The development of highly active antiretroviral therapy has had a profound impact on the epidemiology of AIDS and on the lives of individual patients. Through combinations of antiretroviral drugs, especially protease inhibitors, viral suppression can be achieved. However, adherence to these complex medical regimens and drug interactions have been problems for many patients. In addition, numerous questions remain unanswered, most importantly those regarding the timing of the initiation of treatment, the durability of viral suppression and clinical response, and the optimal "salvage" regimens for patients failing therapy either clinically or virologically.  相似文献   
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