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101.
Russell S. Kirby 《分娩》2004,31(2):148-151
Commentary on: Zhang J, Yancey MK, Henderson CE. U.S. national trends in labor induction, 1989–1998. J Reprod Med 2002;47:120–124.
MacDorman MF, Mathews TJ, Martin JA, Malloy MH. Trends and characteristics of induced labour in the United States, 1989–98. Paediatr Perinat Epidemiol 2002;16:263–273.
Kozak LJ, Weeks JD. U.S. trends in obstetric procedures, 1990–2000. Birth 2002;29:157–161. Abstract: Three recent studies examined the national trend in labor induction in the United States. All show a doubling in the rate of induction during the 1990s, although vital statistics data show a consistently higher trend than that obtained from national hospital discharge data. Neither data source adequately documents the full range of indications for induction, its timing, hospital staffing considerations, and other factors that may play a role. Although rates of induction of labor may be leveling off, despite a lack of scientific evidence for its widespread use, rates are likely to remain at current levels for the next few years.  相似文献   
102.
The cattle major histocompatibility complex (MHC) class II DR gene product is a heterodimer encoded by the BoLA-DRA and -DRB3 genes. Several groups have isolated cDNA and genomic clones for these genes, but their full genomic organization has not been described. We used a combination of long-range polymerase chain reaction (PCR), cloning and sequencing to define the organization of the DRB3 gene on existing genomic clones and in genomic DNA. We estimate the size of the coding region to be 11.4 kbp. Sequencing of full-length PCR clones from two different haplotypes confirmed that they carried complete DRB3 genes and allowed the design of probes and primers to isolate and characterize the DRB3 promoter and 3' end. Fragments carrying the 5' end of the DRB3 gene and its promoter were identified on bacterial artificial chromosome (BAC) clones carrying the BoLA-DR genes. A 10-kbp promoter fragment was subcloned from one clone and a 1.7-kbp region including exon 1 and the promoter was sequenced. A 3-kbp fragment encoding exons 4-6 and the entire 3' untranslated region of the DRB3 gene was isolated from lambda clone A1 and sequenced. This provides us with improved characterization of the DRB3*0101 and DRB3*2002 alleles, and also subcloned 5' and 3' flanking regions of the polymorphic DRB3 gene for use in functional studies.  相似文献   
103.
BACKGROUND: Abnormalities in the limbic-hypothalamic-pituitary-adrenal (LHPA) axis have been implicated in the pathogenesis of obsessive-compulsive disorder (OCD). To our knowledge, however, no prior study has measured pituitary gland volume in OCD. METHODS: Volumetric magnetic resonance imaging studies were conducted in 31 psychotropic drug-na?ve children (10 boys, 21 girls) aged 8-17 years and 31 case-matched healthy comparison subjects. RESULTS: Pituitary volume was significantly smaller in patients with OCD as compared with healthy control subjects (11% smaller). Smaller pituitary volume in patients with OCD was associated with increased compulsive but not obsessive symptom severity. Boys with OCD had smaller pituitary gland volumes compared with control boys (20% smaller). No significant differences in pituitary volume were observed between girls with OCD and control girls. Boys with OCD had significantly smaller pituitary volumes than girls with OCD (31% smaller), whereas control boys also had smaller pituitary gland volumes compared with control girls (21% smaller). CONCLUSIONS: These findings provide new evidence of reduced pituitary volume in pediatric OCD that seems to be more prominent in male patients. The observed alterations in pituitary volume are consistent with neuroendocrine studies that have reported abnormalities in the LHPA axis in OCD.  相似文献   
104.
We have examined the actions of vasoactive intestinal peptide (VIP) and certain other known immune modulators on a nuclear pool(s) of protein kinase C (PKC) in isolated rat splenocyte nuclei. Rat splenocyte nuclei pure by enzymatic and electron microscope criteria demonstrated a time- and concentration-dependent activation of nuclear PKC (nPKC) by VIP. A biphasic pattern of three bell-shaped curves was observed with peak phosphorylation at 10−15, 10−9 and 10−6M VIP. The phosphorylation of endogenous nuclear substrates was characterized as a PKC-mediated event by use of three known PKC inhibitors, 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7), sphingosine, and staurosporine, which produced similar phosphate incorporation measurements. Also, this activity was blocked with the addition of a monoclonal antibody to PKC. Inhibitors of the ability of VIP to activate nPKC included somatostatin, 8-bromo-cAMP, peripheral benzodiazepine receptor modulators, and the PKC inhibitors, sphingosine and staurosporine. These data have direct relevance to our knowledge of cell-mediated immunity.  相似文献   
105.
This paper reviews the important concepts about varicella-zoster virus (VZV) infection, varicella (chickenpox), and herpes zoster (shingles, zoster) during pregnancy and the peripartum period. The majority of the U.S. population has had chickenpox during childhood, leaving only about 10% of adults over the age of 15 susceptible to the virus. However, nonimmune adults, including pregnant women, are at greater risk for complications and mortality when they contrac varicella. The virus is also teratogenic. The implication of VZV infection during pregnancy and the perinatal period are presented. Risks such as varicella pneumonia and congenital defects can be serious even though the incidence during pregnancy is low, one to five per 10,000 pregnancies. Management and treatment plans are presented. Counseling and education aimed at prevention or modification of the infection in the mother and baby is outlined.  相似文献   
106.
107.
Engineering of a variety of rodent tumour cells to secrete either interleukin 2 (IL-2), or interleukin 4 (IL-4), has been demonstrated to reduce their tumorigenicity. However the mechanisms of action of secreted IL-2 and IL-4 have not been compared in a single rodent tumour. Here we demonstrate that the weakly immunogenic murine fibrosarcoma FS29 had reduced growth rate and in some cases was rejected by syngeneic animals, when modified to secrete either IL-2 or IL-4, but not IL-5. Immunohistochemical analysis of tumour nodules undergoing regression showed stimulation of a largely lymphocytic infiltrate by IL-2 and a macrophage and granulocyte infiltrate, with a small number of lymphocytes by IL-4. Indeed, secretion of low levels of IL-2 and IL-4 in combination resulted in optimal rejection, suggesting that the two cytokines might mobilise different and complementary effector cell mechanisms. Both IL-2 and IL-4-secreting cells failed to induce the rejection of admixed, unmodified FS29 cells. The loss of cytokine secreting cells from such admixtures occurred more rapidly for IL-2-secreting cells. Injection of IL-4-secreting, but not IL-2-secreting FS29 cells could protect mice from a delayed challenge with unmodified FS29 cells. These data suggest that IL-4 secretion stimulates the better long-term host anti-tumour response.  相似文献   
108.
109.
The effect of attention on memory was examined in three studies. In all three, the subjects were instructed to remember the items of one color from an array that contained items of two colors. Subsequently, the subjects were asked to reproduce items of both colors. Almost all of the items that the subjects remembered were those to which they had attended. The parameters of sex, color, and mode of presentation (verbal and drawing) were not significant. Head injury did not disrupt this effect. On the basis of this effect, it was theorized that the strength of a memory store is related directly to the strength of attention.  相似文献   
110.
K L Margolis  K L Nichol  G A Poland  R E Pluhar 《JAMA》1990,264(9):1139-1141
Concern about side effects constitutes a major deterrent to patient compliance with influenza vaccination, yet there is a paucity of data about the occurrence of adverse reactions in the population targeted for immunization. We conducted a randomized, double-blind, crossover trial to compare the frequency of adverse reactions following administration of 1988-1989 trivalent split-antigen influenza vaccine and saline placebo. Outpatient veterans 65 years of age or over (n = 336) were recruited by mail and were randomly assigned to receive vaccine followed 2 weeks later by placebo injection or placebo followed 2 weeks later by vaccine. There was no significant difference between influenza vaccine and placebo with respect ot the proportion of subjects reporting disability or systemic symptoms.  相似文献   
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