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81.
Chlamydia trachomatis is currently the most common sexually transmitted disease in the United States. The prevalence in pregnant women ranges between 2% and 47%. It is well known that C trachomatis can be transmitted from the genital tract of an infected mother to her newborn infant, causing conjunctivitis or pneumonia or both, along with their longstanding complications. A review of the literature failed to show, however, conclusive evidence of transmission of infection to the newborn infant when the infant was born by cesarean section with intact amniotic membranes. We present a case of a young black woman with a history of chlamydia cervicitis during pregnancy whose infant was delivered by cesarean section because of failure to progress. She gave birth to a healthy term infant who developed ophthalmia neonatorum on the 3rd day of life. Examinations of conjunctival scrapings with direct fluorescent staining (chlamydia MicroTrak) performed on the 1st and 3rd day of life were positive. The initial test was performed because of the maternal history. The infant was mildly symptomatic at the time the study was repeated for confirmation. Our findings strongly suggest the possibility of either transmembrane or transplacental route of infection in the pathogenesis of neonatal chlamydia infection. Further study is needed to confirm this possibility.  相似文献   
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This communication describes the design and application of a receiver coil operating at liquid nitrogen temperature and intended as a surface coil in a whole-body imager. Its particular application is seen as the external receiver for parasitic internal or implanted detectors.  相似文献   
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Portion Sizes in Dietary Assessment: Issues and Policy Implications   总被引:5,自引:0,他引:5  
Accurate estimates of energy and nutrient intake of individuals and populations are contingent on the reliability of information obtained about food intake, food composition, and portion size. This article reviews issues related to the definition, determination, and use of portion sizes in dietary assessment and public education.  相似文献   
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The term spasticity is used to describe many relatively unrelated syndromes and, because they share few common pathophysiologic mechanisms, it is not possible to define the physiology or pharmacology of spasticity. In patients with spastic paresis, it is the latter negative symptom (rather than the spasticity) that accounts for almost all the functional disability. Clinical neurophysiologic techniques are useful for categorization of patients with clinically identical syndromes into subgroups which respond to different therapies. Fusimotor or spindle primary afferent hyperactivity have not been demonstrated in spastic patients; reduction in central inhibitory mechanisms probably accounts for spastic hyper-reflexia. Increased passive muscle stiffness may also be clinically significant. Therapies for spasticity include elimination of causative or enhancing factors, frequent muscle stretching, surgical approaches and chemotherapy. The latter includes dantrolene (which weakens muscles), baclofen (particularly useful for reduction of flexor spasms and flexor dystonia in patients with spinal lesions) and diazepam.  相似文献   
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