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In October 1989 a representative sample consisting of 359 women (response rate = 77.9%) and 400 men (response rate = 76.3%) aged 16-20 years old was interviewed by the professional interviewer staff of the Institute for Social Research. The purpose of the investigation was to illustrate whether AIDS and "Safe sex"-campaigns have influenced young people. This paper consider the attitudes to contraception among teenagers. Generally, the reports are in accordance with an increasing popularity of the condom. Almost all answered that it was all right for a girl to bring a condom. The majority (313 (89.4%) among women and 311 (78.7%) among men) reported both partners to be responsible in relation to contraception. Still, it is commonly the female who brings up the question. Communication about contraception between the female and the male partner is of importance in order to impede sexually transmitted diseases and reduce the number of legally induced abortions among teenagers. The widespread attitude towards contraception as being a joint concern forms an appropriate basis to attain equality between the sexes in relation to communication about contraception.  相似文献   
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One of the diagnostic possibilities to consider when a patient presents with cough, fever, dyspnea, or pulmonary infiltrates is hypersensitivity pneumonitis. Some of the problems encountered in diagnosis of diffuse lung disease are illustrated in two case reports. In one of the cases, interstitial pneumonitis of insidious onset was attributed to inhalation of thermophilic organisms in moldy silage. In the other, the outstanding pathologic feature was bronchiolitis obliterans, and circumstantial evidence pointed to a home humidifier as the source of the problem.  相似文献   
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The authors present clinical and case material on two male triplets with aberrant gender identity. Their findings coincide with those of the few family studies reported in which there were two or more transsexual members; they also reveal patterns generally in keeping with the psychological determinants of transsexualism suggested by Stoller.  相似文献   
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Invasive group A streptococcus (GAS) infections are emerging diseases; however, person-to-person transmission of invasive GAS producing life-threatening infection has been observed rarely. We report a small intrafamilial cluster of life-threatening GAS infections. A previously healthy 47-year-old father developed necrotizing fasciitis of the neck. Two days later, his 16-year-old daughter developed streptococcal angina, pneumonia, and pleural empyema. Both patients had signs of streptococcal toxic shock syndrome. Pulsed field gel electrophoresis revealed that the M6 strains of GAS isolated from the father and daughter had identical patterns. Cases of person-to-person transmission of invasive GAS infection reported in the literature are also reviewed.  相似文献   
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Initiation of Myxococcus xanthus multicellular development requires integration of information concerning the cells' nutrient status and density. A gain-of-function mutation, sasB7, that bypasses both the starvation and high cell density requirements for developmental expression of the 4521 reporter gene, maps to the sasS gene. The wild-type sasS gene was cloned and sequenced. This gene is predicted to encode a sensor histidine protein kinase that appears to be a key element in the transduction of starvation and cell density inputs. The sasS null mutants express 4521 at a basal level, form defective fruiting bodies, and exhibit reduced sporulation efficiencies. These data indicate that the wild-type sasS gene product functions as a positive regulator of 4521 expression and participates in M. xanthus development. The N terminus of SasS is predicted to contain two transmembrane domains that would locate the protein to the cytoplasmic membrane. The sasB7 mutation, an E139K missense mutation, maps to the predicted N-terminal periplasmic region. The C terminus of SasS contains all of the conserved residues typical of the sensor histidine protein kinases. SasS is predicted to be the sensor protein in a two-component system that integrates information required for M. xanthus developmental gene expression.  相似文献   
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