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31.
The frequency of deletion of short arm satellites has been examined in various populations. Four out of 2509 males in psychiatric institutions and prisons had Dps- or Gps- (1·6 per 1000), and five out of 6187 persons in the general population had Dps- or Gps- (0·8 per 1000). The difference is not significant.

The segregation rate of the chromosome with lack of short arm satellite material did not deviate from unity in the few families where such calculations were possible. There was no increase in abortions or non-disjunction in the families with an acrocentric chromosome lacking short arm satellite material.

The study indicates that the frequency of Dps- and Gps- in the population is between 0·5 and 1·0 per 1000 and that the lack of short arm satellite material is without any deleterious effect on phenotype.

  相似文献   
32.
Zusammenfassung Es gibt zahlreiche Ursachen der Subarachnoidalblutungen. Naturgemäß müssen dieselben in Gefäßveränderungen gesucht werden.Eine sog. idiopathische, spontane, essentielle Blutung haben viele Autoren (insbesondereHess) dadurch begründet, daß jede erkennbare Gefäßveränderung oder sonstige äußere Beeinflussung in einer großen Anzahl von Fällen, besonders bei Jugendlichen, nicht nachgewiesen werden kann. Diese Fälle wurden mit einer angioneurotischen Diathese begründet.Sicher gibt es derartige Fälle; jedoch ist diese Krankheitsform mit großer Vorsicht und Kritik zu bewerten, da verborgene Ursachen verschiedener Art, besonders das Basalaneurysma, vorhanden sein können.D. 8.  相似文献   
33.
The quality parameters for the detection of microsporidia in identical sets of 50 stool samples were determined for six laboratories where technicians used light microscopy and for six laboratories where technicians used PCR. The average overall sensitivities were 67% (89% for patient samples only) for the PCR laboratories and 54% (80% for patient samples only) for the light microscopy laboratories. Specificities were 98 and 95%, respectively. Differences in results were most apparent between the individual laboratories rather than between the two major methods used.  相似文献   
34.
A radioimmunoassay (RIA) which depends on the property of protein A ofStaphylococcus aureus to combine with the Fc-fragment of immunoglobulins was developed.This technique was employed to measure antibodies in human and various animal sera. It could be demonstrated that the staphylococcal RIA was at least as sensitive as the previously described radioimmunoprecipitation technique in detecting antibodies toM.pneumoniae in human sera. In addition, antibodies toM.pneumoniae could be demonstrated in sera of hamsters intranasally inoculated with the organisms. Antibodies could also be demonstrated in rabbit sera after immunization withM.pneumoniae. The test proved to be considerably more sensitive than conventional tests for detection of antibodies to the organisms. The test requires only small amounts of reagents and is relatively inexpensive.The results were presented in a preliminary form at the annual meeting of the Local Branch of the American Society for Microbiology, Frankfurt, March 1976 and the 77th ordinary meeting of the Society for General Microbiology, Glasgow, September 1976  相似文献   
35.
Mammalian embryos cannot survive without the placenta. Development of the human placenta requires trophoblast proliferation, differentiation, and invasion as well as highly coordinated modulation of the maternal uterus. HtrA1 is a member of the recently identified mammalian HtrA (high temperature requirement factor A) serine protease family with a high level of expression in the placenta. In this study, we examined whether HtrA1 expression (mRNA and protein) is associated with placental development in the human. HtrA1 is up-regulated in both endometrial glands and decidual cells during endometrial preparation for embryo implantation and during first-trimester pregnancy at placentation. HtrA1 expression was also detected in certain trophoblast subtypes during early pregnancy. The villous syncytiotrophoblast and cytotrophoblast showed the strongest expression while the interstitial extravillous trophoblast showed the lowest or no expression of HtrA1. The distinct distribution of HtrA1 at the maternal-trophoblast interface suggests that HtrA1 may play a role in placental development.  相似文献   
36.
Murine plasmacytoid dendritic cells (pDCs) have been credited with a unique ability to express indoleamine 2,3-dioxygenase (IDO) function and mediate immunosuppression in specific settings; yet, the conditions of spontaneous versus induced activity have remained unclear. We have used maneuvers known to up-regulate IDO in different cell types and have examined the relative efficacy and mechanisms of the induced activity in splenic pDCs, namely, after specific receptor engagement by CTLA-4-Ig, CD200-Ig or CD28-Ig, the latter in combination with silenced expression of the suppressor of cytokine signaling 3 (SOCS3) gene. We found that pDCs (CD11c+ mPDCA-1+ 120G8+) do not express IDO and are not tolerogenic under basal conditions. B7-1 engagement by CTLA-4-Ig, CD200R1 engagement by CD200-Ig and B7-1/B7-2 engagement by CD28-Ig in SOCS3-deficient pDCs were each capable of initiating IDO-dependent tolerance via different mechanisms. IFN-gamma was the major cytokine responsible for CTLA-4-Ig effects, and type I IFNs for those of CD200-Ig. Immunosuppression by CD28-Ig in the absence of SOCS3 required IFN-gamma induction and IFN-like actions of IL-6. Therefore, although pDCs do not mediate IDO-dependent tolerance constitutively, multiple ligands and cytokines will contribute to the expression of a tolerogenic phenotype by pDCs in the mouse.  相似文献   
37.
Enterohemorrhagic Escherichia coli (EHEC) produces Shiga-like toxins (SLT), potent protein synthesis inhibitors. To further dissect the role of SLT-II in the course of disease, we have constructed E. coli TUV86-2, an isogenic SLT-II-negative mutant of EHEC strain 86-24. The slt-ii gene was inactivated by suicide vector mutagenesis. We also isolated derivatives of strain 86-24 that were cured of the phage carrying the toxin genes.  相似文献   
38.
39.
BACKGROUND: Human cytomegalovirus (CMV) is the most common cause of viral intrauterine infection. Primary CMV infection in early pregnancy bears a high risk of fetal damage. Accurate measurement of CMV-specific IgG avidity may help to improve the serodiagnosis of CMV-infected women by determining the time of infection and fetal outcome. OBJECTIVES: To study the performance of the CMV avidity assay with the fully automated Vidas analyzer (bioMérieux) as a function of the concentration of CMV-specific IgG present in the serum sample. STUDY DESIGN: Eighty-two serum samples were investigated from 3 clinical scenarios: 18 individuals with sera negative for CMV-specific IgG and IgM (control group), 20 pregnant women (44 samples) containing CMV-specific IgG- and IgM-antibodies suggesting acute or recent primary infection and 20 patients with evidence of past infection (CMV-IgG positive and CMV-IgM negative). RESULTS: In the group with presumed acute or recent primary infection 12 of 44 sera had CMV-specific IgG values above 100 arbitrary units (AU, bioMérieux)/ml and in these cases an increase in AI was measurable upon dilution of the serum sample. In two cases, AI's were shifted towards or above the cut-off value of AI>or=0.8, indicative of past infection. Dilution of sera which were CMV-specific IgM positive and had specific IgG concentrations of 相似文献   
40.
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