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81.
Regulation of the immune system by neuroendocrine hormones is receiving increased attention. Prolactin, a hormone normally associated with lactation, has been shown recently to reconstitute immunosuppressed hypophysectomized rats. The present studies demonstrate that prolactin administration to normal mice results in a biphasic stimulation of antibody production to sheep red blood cells. While 100 and 200 micrograms bovine prolactin/animal stimulated antibody production, 400 micrograms had no effect. Potentiation of lectin-induced T-cell mitogenesis by prolactin was also biphasic. As the concentration of prolactin increased the incorporation of [3H]thymidine into the cells first increased and then decreased. Decreasing serum prolactin levels with the dopaminergic agonist bromocriptine resulted in a reduction of antibody titers to sheep erythrocytes and a modulation of thymic weight. These data show that prolactin can stimulate the immune system in a biphasic manner and that a reduction in the basal levels of this hormone results in an attenuated immune response.  相似文献   
82.
Multiple sclerosis and the workplace: report of an industry-based cluster   总被引:2,自引:0,他引:2  
E C Stein  R B Schiffer  W J Hall  N Young 《Neurology》1987,37(10):1672-1677
Eleven cases of MS occurred within a 10-year period in a zinc-related manufacturing plant. The observed disease incidence was greater than expected from population data, using multiple approaches to statistical analysis (p less than or equal to 0.01). A case-control study, performed to examine several zinc parameters in blood, failed to indicate specific abnormalities among the MS patients, but all subjects (both MS and controls) working in the plant demonstrated higher serum zinc levels than all subjects (MS and controls) not working there.  相似文献   
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OBJECTIVES: Very low birth weight (VLBW) infants are vulnerable to nosocomial infections and subsequent morbidity; including infections caused by Staphylococcus aureus: 85% of nosocomial S. aureus infections are caused by capsular polysaccharide (CPS) types 5 and 8. Altastaph is a polyclonal investigational human immunoglobulin G (IgG) with high levels of opsonizing S. aureus CPS types 5 and 8 IgG. METHODS: A Phase 2 clinical trial to assess the safety and kinetics of Altastaph in VLBW infants. Neonates in this multicenter study were randomized to receive two identical 20 ml/kg i.v. infusions of either 0.45% NaCl placebo or 1000 mg Altastaph/kg. Each infant was followed for 28 days after the second infusion or until discharge. Serum S. aureus CPS types 5 and 8 IgG levels were measured preinfusion and at various times after each infusion. RESULTS: Of 206 neonates, 158 received both infusions. Adverse events were similar in the two treatment groups. Six subjects (3% in each group) discontinued owing to an adverse event. Geometric mean anti-type 5 IgG levels were 402 and 642 mcg/ml 1 day following infusion of the first (day 0) and Second (day 14) doses, respectively, in neonates < or =1000 g and slightly higher in neonates 1001 to 1500 g. Trough levels before second infusion were 188 mcg/ml. Type 8 IgG levels were similar. Geometric mean IgG levels among placebo recipients were consistently <2 and <5 mcg/ml for types 5 and 8 in both weight groups. Three episodes of S. aureus bacteremia occurred in each arm. CONCLUSIONS: Infusion of Altastaph in VLBW neonates resulted in high levels of specific S. aureus types 5 and 8 CPS IgG. The administration of this anti-staphylococcal hyperimmune globulin was well tolerated in this population.  相似文献   
84.
In a prospective, randomized study of insemination with donor semen, intracervical insemination by straw was compared with insemination using a cervical cap with an intracervical reservoir. A total of 91 patients completed 486 treatment cycles. There were no significant differences in age, parity, indication for insemination by donor, or method of cycle monitoring between women who became pregnant and those who did not conceive with either insemination method. In 236 standard intracervical insemination cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude pregnancy rates and the cumulative pregnancy rates calculated by the Kaplan-Meier life-table method were significantly different (chi(2)-test, P < 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates in artificial insemination with cryopreserved donor semen may be improved by the use of a cervical cap when compared to cervical insemination by straw. The use of the cervical cap may prolong the exposure of the spermatozoa to the cervical mucus and prevent the backflow of semen into the vagina.   相似文献   
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The periodontal disease syndromes present the practitioner with an extensive array of clinical conditions. However, by performing a careful examination and recording of findings, the clinician will provide order to this seemingly complex picture. This careful and reasoned approach is based on a logical sequence starting with clinical observations that lead to a diagnosis of the disease entity present. This correct diagnosis in turn will lead to establishment of the prognosis and the therapeutic approach. By following these precepts, the practitioner ensures a sound biologic basis for his or her efforts. The end result is the realization of the goal of dental therapy that her is for the patient to maintain dentition in health, comfort, and function for a lifetime and minimize the potential for urgent periodontal needs.  相似文献   
89.
The effects of functional endoscopic sinus surgery (FESS) on sinus and midfacial development remain unclear. The authors report five children who, at a median age of 30 months, underwent FESS for refractory sinusitis. Three of the children had cystic fibrosis, and two had asthma. Preoperative computed tomographic (CT) scanning showed symmetric maxillary sinus development with varying degrees of mucosal disease. At a mean of 42 months after surgery, CT scans were obtained to evaluate recurrent symptoms in the five children. The scans showed unilateral maxillary hypoplasia in four children and bilateral maxillary sinus hypoplasia in one child. No child had clinically apparent facial asymmetry or midfacial hypoplasia. The authors also discuss the factors involved in maxillary sinus pneumatization, the possible effects of sinus surgery on sinus development, and the clinical implications of “acquired” maxillary sinus hypoplasia. Laryngoscope, 106:1210-1213, 1996  相似文献   
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