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181.
Summary Throughout history, different etiologies have been suggested for torus palatinus. In more recent years, however, torus palatinus has been attributed to heredity; a case which confirms this is presented. The relevant literature is reviewed.  相似文献   
182.
The purpose of this study was to develop and evaluate a measure of perceived disruption during rebuilding following a disaster. Two eight-item scales, which measured intensity of disruption during the entire repair phase (Intensity-RP) and intensity of disruption during the past month (Intensity-PM) were developed and administered to 135 survivors of Hurricane Andrew. At 9 to 12 months postdisaster, Intensity-RP and Intensity-PM were both significantly associated with scores on the Global Severity Index of the SCL-90-R, and with scores on the Impact of Event-Intrusion Scale; Intensity-PM alone was significantly associated with PTSD scores. Regression analyses indicated that each scale contributed significant unique variance in predicting mental health symptoms, even after controlling for relevant demographic and initial disaster exposure variables.  相似文献   
183.
High pressure liquid chromatography (HPLC) was used to fractionate redissolved polyethylene glycol (PEG) precipitates isolated from the sera of normal volunteers and from patients with IgA nephropathy (IgAN) and systemic lupus erythematosus (SLE), 2 diseases characterized by elevated levels of circulating immune complexes. The individual fractions were analyzed by solid phase ELISA for IgA, IgM, C3, IgG, and complexes of IgG-IgA and IgG-C3. Although PEG precipitates were enriched for high molecular weight IgA and IgG (presumably bound within CIC), significant amounts of IgM, unbound IgG and C3 were also present. The quantities of the PEG-precipitable proteins did not correlate with their serum concentrations. IgG-IgA and IgG-C3 complexes were found in all precipitates examined, but the levels of complexes were higher in both patient groups. These results indicate that PEG precipitates a considerable quantity of proteins not bound in immune complexes. There appeared to be greater protein precipitation from sera of the patient groups compared to the amount precipitated from the normal sera. These results suggest that an understanding of the mechanism of PEG precipitation may be important in defining abnormalities in IgAN, SLE and perhaps other diseases characterized by elevated levels of CIC. In addition, the possibility of undetected CIC in PEG precipitable material must be considered.  相似文献   
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185.
Targeted mutagenesis of the retinoic acid receptor alpha (RAR alpha) gene has revealed its essential role in spermatogenesis. Although cells in all stages of spermatogenesis were detected in RAR alpha(-/-) testes, there was an increase in degenerating pachytene spermatocytes and a temporary developmental arrest in step 8-9 spermatids in the first wave of spermatogenesis, a delay in the onset of the second wave, and a temporary arrest in preleptotene to leptotene spermatocytes in the first, second, and third waves. A striking aspect of the mutant phenotype was the failure of spermatids to align at the tubular lumen at stage VIII. Furthermore, there were missing or decreased numbers of the predicted cell types in tubules, and they exhibited a profound asynchrony of mixed spermatogenic cell types. In vivo bromodeoxyuridine labeling revealed a significant decrease in germ cell proliferation in both juvenile and adult RAR alpha(-/-) testes and confirmed the arrest at step 8-9 spermatids. Retinoid signaling through RAR alpha, thus, appears to be critical for establishment of synchronous progression of spermatogenesis and the subsequent establishment of correct cellular associations.  相似文献   
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187.
The growth at — 1.5°C of Lactobacillus delbrueckii, a meat spoilage organism, was evaluated on vacuum‐packaged lamb legs obtained from animals immunized against that organism. Growth was significantly lower than that on similarly treated legs obtained from non‐immunized lambs. These findings suggest that immunization against spoilage organisms may contribute toward increasing the chilled storage life of fresh meat.  相似文献   
188.
An accurate prediction of birth weight during gestation can provide useful information for assessing fetal and newborn health status, enabling the clinician to better predict infant morbidity and mortality. Two previously reported standard methods for birth-weight estimation used data collected in utero to derive formulas by least-squares linear regression. The rationale for the inclusion of particular variables in these equations, however, has not been clearly defined. This study was undertaken to examine the efficacy of some previously used variables as well as some new variables in estimating fetal birth weight. The authors used measurements of femur length, biparietal diameter, and abdominal circumference from 107 fetuses (2500 to 4000 g) as variables to compare the two standard methods of birth-weight estimation. A new formula is presented that is derived from a simple model based on the known relationship between volume and weight. The head is represented as a sphere and the body as a cylinder. This study presents a more systematic approach to formula development in which statistical biases are minimized by examining the underlying distributions of the variables used to predict birth weight.  相似文献   
189.
The development of selective irreversible ligands has proven to be an invaluable technique for the isolation, purification and characterization of many receptor proteins. An isothiocyanato-derivative of the muscarinic antagonist aprophen was synthesized and evaluated as a potential irreversible ligand for muscarinic receptors. This compound (aprophit) displaced [3H]N-methylscopolamine binding from rat cerebral cortex with a Ki of 3.1 x 10(-7) M. The inhibition was concentration-dependent and could not be reversed by extensive washing. Aprophit inhibited the acetylcholine-stimulated release of catecholamines from isolated, perfused guinea pig adrenal glands in a concentration-dependent manner. This inhibition was not reversed by perfusing the tissue with Locke's solution and was not due to a non-selective acylation by the isothiocyanate function. The data suggest that aprophit is selectively acylating muscarinic receptor proteins and thus may be useful in their further characterization.  相似文献   
190.
HLA-DR expression in neuroendothelial cells (NEC) was studied during the course of SIV encephalitis in rhesus monkeys. HLA-DR determinants were detected on NEC in monkeys with SIV encephalitis, but not in control animals. In situ hybridization with an SIV probe indicated that HLA-DR expression was not a consequence of SIV replication within NEC. Cultured rhesus NEC stimulated with gamma interferon expressed HLA-DR to a higher degree than cultured brain fibroblasts or astrocytes. These data support the contention that NEC participate in retrovirus-induced inflammation and autoimmunity within the central nervous system.  相似文献   
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