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61.
62.
Thirty-four adults were vaccinated with 1/50 of the usual dose of meningococcal polysaccharide vaccine (1 microg of A, C, Y, and W135 polysaccharides, given intramuscularly). This dose was selected as a probe to assess B cell memory. The probe elicited meningococcal C bactericidal antibody responses in all 18 adults who had been vaccinated 4 years earlier with an investigational meningococcal A and C oligosaccharide-protein conjugate vaccine and in the majority of the 11 subjects vaccinated for the first time. In contrast, the responses of the 5 adults given a full dose of licensed polysaccharide vaccine 4 years earlier were <1/10 of those of the other 2 groups. Thus, adults previously given a full dose of meningococcal polysaccharide vaccine show evidence of immunologic refractoriness to group C polysaccharide, whereas refractoriness is not observed after conjugate vaccination. These findings have implications for the use of meningococcal polysaccharide vaccine when the risk of disease is low.  相似文献   
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64.
A case of pulmonary Mycobacterium avium (M. avium) disease associated with idiopathic CD4+ T lymphocytopenia is reported. A rapidly growing pulmonary nodule was detected on a chest roentgenogram in a young man. Bronchoscopic examination revealed M. avium infection. Hematological studies showed a low CD4+ cell count in the absence of any identifiable immunodeficiency, including human immunodeficiency virus (HIV) infection. With the combination of chemotherapy and surgery, he had a good clinical outcome. Idiopathic CD4+ T lymphocytopenia should be considered in patients with unexplained opportunistic infection.  相似文献   
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66.
The primary goal in the medical management of ventricular septal defect complicating myocardial infarction is to support cardiac function and control symptoms, if possible, for a period of 4 to 6 weeks. If the patient survives this period, surgical correction of the defect is technically easier and safer. In many cases, However, cardiac function is severly compromised, intractable biventricular failure develops,early operation is necessary and the likelihood of successful repair is diminished.  相似文献   
67.
All of 16 infants with neonatal meningitis treated during a 30-month period were found to have accompanying ventriculitis at the time of the initial ventricular puncture. Fifteen of these infants were caused by gramm-negative organisms. All infants received antibiotics systemically and intraventricularly via an implanted ventriculostomy reservoir or by direct ventricular injection. Antibiotic concentrations within the ventricular fluid were monitored during chemotherapy; the complications encountered during treatment are discussed. Fifteen infants survived the infection; of these, seven infants were normal at follow-up examinations. In our experience intraventricular chemotherapy as an adjunct to systemic administration of antibiotics has greatly reduced the mortality rate in neonatal meningitis.  相似文献   
68.
Fecal neutral steroids and bile acids were measured in patients with familial polyposis, family controls who are immediate relatives of patients, and controls other than relatives. All subjects were consuming a mixed Western diet at the time of collection of stool specimens. Although the total fecal neutral sterol concentrations were not different between the groups, the patients with familial polyposis excreted a high amount of cholesterol and low levels of coprostanol and coprostanone compared with other groups. Patients with familial polyposis excreted levels of total bile acids in their feces comparable to those excreted by controls; lithocholic acid excretion was decreased in patients with familial polyposis. These findings suggest that analysis of stools for cholesterol and its metabolites be useful in screening the siblings of polyposis families for latent disease.  相似文献   
69.
Malignant melanoma of the mucous membranes is rare and has a very poor prognosis. When localized in the nose, the tumor becomes apparent late in the course of the disease with nasal obstruction and epistaxis. Distant metastases are uncommon, but any organ of the body can be involved. A case of a malignant melanoma of the nasal mucosa with metastasis to the small intestine is presented, and the natural history of the metastatic disease is discussed.  相似文献   
70.
Analysis of measurements from the tali of 21 individual fossil primates from Africa shows that the specimens fall into five clearly defined groups. Accordingly, these specimens have been included as groups along with extant species in a subsequent canonical analysis thus allowing the fossils to play their part in the determination of the canonical separations. The results of this procedure show that the five fossil groups lie in a part of the canonical space not occupied by any extant African primate. Their positions are between the envelope of Asiatic apes (Hylobates and Pongo) and the envelope of African forms near the edge which contains Pan and Papio. One fossil group is so similar to Hylobates that its talus may have functioned in locomotion in a parallel manner. Others lie near to Pongo in directions proceeding towards Pan and Papio and it is possible that this similarity may indicate remnants of morphological adaptation for climbing in these fossils. At the same time, however, individual specimens are closer to one or another of the extant groups and this considerable spread suggests that the locomotor adaptations as evidenced by talar morphology, of the primate fauna in Africa, may have been very different from those of the present day. This would not the inconsistent with the different habitats, floras and non-primate faunas that may have characterized the East African scene at these earlier times. Particular fossils from Olduvai and Kromdraai that are supposed to be australopithecine and therefore bipeds, are confirmed (Oxnard, '72; Lisowski et al., '74) as being totally different from man in their talar morphology and essentially rather similar to the majority of the other fossil tali examined.  相似文献   
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