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61.
We first examined relations between psychiatric disorder and coronary heart disease (CHD) in 77 patients presenting with chest pain. The coping profiles of chest pain patients with and without psychiatric disorder and CHD were then compared. Psychiatric patients with no medical illness (n = 129) were also studied. On the basis of previous research we hypothesized specific coping differences across the groups. As expected, chest pain patients without psychiatric disorder scored significantly higher on a problem-focused coping scale than chest pain patients with psychiatric disorder, who in scored higher on this scale than psychiatric patients with no medical illness. The opposite pattern occurred for a measure of wishful thinking. Scores of chest pain patients with psychiatric disorder were higher on a measure of avoidance and lower on a measure of seeking of social supports than those without psychiatric disorder. Scores on a self-blame measure were not different across the groups. The results are discussed in the context of illness behavior and somatization.  相似文献   
62.
The use of plane parallel ionization chambers with electron beams with high dose per pulse entails dose uncertainties due to the overestimation of the ion recombination factor, k, up to 20% if conventional dosimetric protocols are used. In this work MD-55-2 radiochromic films have been used as reference dosimeters to obtain dose to water per pulse DGAF(w) values for three Novac7 (Hitesys) electron beams of E0 = 5.8 MeV. However, the beam calibration by MD-55-2 films is time consuming and the use of plane parallel chambers is fundamental for a periodic quality control procedure. Three plane parallel chambers have been used and the general formula for the k determination has been tested using the calibration doses, DGAF(w). In particular, consistent ion recombination factors ksat(V0) (with the ion chamber polarized at V0), that follow the Boag theory, have been estimated at different dose per pulse values for the three plane parallel ionization chambers. This means that at present any ion chamber needs a specific ksat (V0) determination by using a reference dosimeter for which the response is independent of the dose rate. An accurate determination of ksat(V0), using a reference quality beam, can be used to determine the dose to water per pulse for electron beams of different quality and geometrical configuration.  相似文献   
63.
Summary The complete sequences of genomic and defective interfering (DI) RNAs of carnation Italian ringspot tombusvirus (CIRV) were determined. The genome (4760 nt) has an organization identical to that reported for other tombusviruses except that the pre-readthrough domain of the viral replicase encoded by the 5-proximal open reading frame (ORF) is larger. In particular, the N-terminal region of this protein differs from the corresponding region of the other members of the genusTombusvirus andCarmovirus. Two DI RNAs were found in infected tissues whose sequences were completely derived from genomic RNA. The smaller molecule (474 nt) is contained completely within the larger molecule (656 nt), which suggests that it is derived from the larger one.The nucleotide sequence data reported in this paper will appear in the EMBL, GenBank and DDBJ Nucleotide Database under the accession number X85215.  相似文献   
64.
Chediak‐Higashi syndrome (CHS) is a rare autosomal recessive disorder characterized by severe immunologic defects, reduced pigmentation, bleeding tendency, and progressive neurological dysfunction. Most patients present in early childhood and die unless treated by bone marrow transplantation. About 10–15% of patients exhibit a much milder clinical phenotype and survive to adulthood, but develop progressive and often fatal neurological dysfunction. Very rare patients exhibit an intermediate adolescent CHS phenotype, presenting with severe infections in early childhood, but a milder course by adolescence, with no accelerated phase. Here, we describe the organization and genomic DNA sequence of the CHS1 gene and mutation analysis of 21 unrelated patients with the childhood, adolescent, and adult forms of CHS. In patients with severe childhood CHS, we found only functionally null mutant CHS1 alleles, whereas in patients with the adolescent and adult forms of CHS we also found missense mutant alleles that likely encode CHS1 polypeptides with partial function. Together, these results suggest an allelic genotype–phenotype relationship among the various clinical forms of CHS. © 2002 Wiley‐Liss, Inc.  相似文献   
65.
A radio (51Cr) micro-tube leukocyte adherence inhibition assay is described. In this study, murine mononuclear cells were labeled with 51Cr, plated into tissue culture plates with different tumor extracts and counts/min (cpm) of the non-adherent cells were used as a parameter of adherence inhibition. This assay was used to measure anti-tumor immunity, in vitro, in 3 murine tumor systems: MCA-38 colon adenocarcinoma, L1210 lymphoma and P815 mastocytoma. Tumor immunity was detected using 3 doses (0.01-0.001 mg/ml) of tumor extract in the MCA-38 tumor model, and using 2 doses (0.1-0.05 mg/ml) of tumor extract in both the L1210 and P815 tumor models. It was observed that specific tumor-associated adherence inhibition could be measured in the MCA-38 tumor model between days 7 and 22 of tumor growth and in the L1210 and P815 tumor models between days 7 and 17 of tumor growth. The radio-LAI assay described is an easy, specific and reproducible way to measure tumor-associated adherence inhibition, in vitro.  相似文献   
66.
Early motherhood (less than 20 years of age) was found to be significantly correlated (r = .33) with the number of DSM-III symptoms of conduct disorder in a sample of 253 boys aged 6-13 years who had been referred to outpatient clinics. The following models were compared using path analysis: (a) Teenage motherhood, parental antisocial personality, and SES each contribute uniquely to the prediction of childhood conduct problems; (b) teenage motherhood mediates the association of SES and parental antisocial personality with child conduct problems; and (c) teenage motherhood is spuriously related with child conduct problems because of common associations with SES and parental antisocial personality. Model (c) best fit our data. Similar results were obtained whether maternal age at the birth of the firstborn child or the proband child was used to define maternal age and when teenage motherhood was defined as giving birth at less than 18 years.  相似文献   
67.
The 90-kDa antigen, previously identified by the monoclonal antibody 1G7 to be a stage-specific surface protein of metacyclic trypomastigotes of Trypanosoma cruzi, has been further characterized in this study. Experiments of metabolic labeling with [35S]methionine, [2H]mannose and [3H]galactose revealed that the 90-kDa antigen is the main glycoprotein synthesized by metacyclic forms (G strain). Through pulse-chase experiments with [35S]methionine-labeled metacyclic trypomastigotes, it was found that the antigen is synthesized as a 75-kDa precursor polypeptide that is rapidly processed to the mature 90-kDa molecule. When metacyclic trypomastigotes were treated with tunicamycin, the production of 90-kDa antigen was greatly diminished, and the 75-kDa species, which was also expressed on the cell surface, accumulated. Concanavalin A bound strongly to the 90-kDa antigen, but failed to recognize the 75-kDa polypeptide. Treatment of neuraminidase had no effect on the 90-kDa antigen, whereas digestion by endoglycosidase H generated a polypeptide of 82 kDa. Altogether these data indicate that the 90-kDa antigen is a glycoprotein containing N-linked oligosaccharide side chains of the high-mannose type. The 90-kDa glycoprotein may be involved in the process of host cell invasion, since the internalization of metacyclic forms into Vero cells was partially inhibited by monoclonal antibody 1G7.  相似文献   
68.
The influence of age and mammary gland differentiation on the incidence of tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA) was studied by correlating the development of the mammary glands of 20-180-day-old, virgin Sprague-Dawley rats with the number and type of tumors induced by DMBA administered at those various ages. The number of terminal end buds (TEBs), terminal ducts (TDs), and alveolar buds (ABs)/sq mm and their DNA-labeling indices (DNA-LI) were determined. Highest density of TEB occurred when the rats were 20 days old, decreasing thereafter. DNA-LI ranged between 25.2 and 29 in TEB of rats aged 30-55 days, which was coincident with the highest incidence of carcinomas. With aging, the number of TEBs and their DNA-LI decreased and the number of TDs and ABs increased, although with a low DNA-LI, which correlated with a lower incidence of carcinomas and higher incidence of benign lesions.  相似文献   
69.
Seventy-six hearts were studied having no direct communication between the right atrium and the ventricular mass. The different cardiac chamber combinations producing so-called "tricuspid atresia" were considered. The nature of the atrioventricular valve atresia, the morphology of the ventricular mass, the size and position of the interventricular communication, the ventriculoarterial connection, and the presence of subarterial outflow tract obstruction were all analyzed. The majority of cases were of the "classical" type, i.e., absent right atrioventricular connection with the left atrium connected to the left ventricle. In another group there was absence of the right atrioventricular connection but the left atrium drained into the morphologically right ventricle, which was left-sided. In a third group both atrial chambers connected with the ventricular mass but some structure, an imperforate valve or muscular partition, completely blocked the flow pathway through the right side of the heart. All the hearts described are candidates for the Fontan procedure with either an atrioventricular or an atriopulmonary conduit. The surgical options would not be affected by the observed variability at the atrioventricular junction but would be dictated by the feasibility of incorporating the subpulmonary ventricle within the pulmonary circulation.  相似文献   
70.
Altered circulating levels of free fatty acids (FFAs), namely short chain fatty acids (SCFAs), medium chain fatty acids (MCFAs), and long chain fatty acids (LCFAs), are associated with metabolic, gastrointestinal, and malignant diseases. Hence, we compared the serum FFA profile of patients with celiac disease (CD), adenomatous polyposis (AP), and colorectal cancer (CRC) to healthy controls (HC). We enrolled 44 patients (19 CRC, 9 AP, 16 CD) and 16 HC. We performed a quantitative FFA evaluation with the gas chromatography–mass spectrometry method (GC–MS), and we performed Dirichlet-multinomial regression in order to highlight disease-specific FFA signature. HC showed a different composition of FFAs than CRC, AP, and CD patients. Furthermore, the partial least squares discriminant analysis (PLS-DA) confirmed perfect overlap between the CRC and AP patients and separation of HC from the diseased groups. The Dirichlet-multinomial regression identified only strong positive association between CD and butyric acid. Moreover, CD patients showed significant interactions with age, BMI, and gender. In addition, among patients with the same age and BMI, being male compared to being female implies a decrease of the CD effect on the (log) prevalence of butyric acid in FFA composition. Our data support GC–MS as a suitable method for the concurrent analysis of circulating SCFAs, MCFAs, and LCFAs in different gastrointestinal diseases. Furthermore, and notably, we suggest for the first time that butyric acid could represent a potential biomarker for CD screening.  相似文献   
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