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991.
BACKGROUND: Previous studies on assortment for psychiatric disorders have reported discrepant findings. We aimed to test whether there is a significant association for psychiatric diagnoses, including alcoholism, generalized anxiety disorder, major depressive disorder, panic disorder and phobias between husbands and wives in two population-based samples. We further evaluated whether marital resemblance occurs primarily within or across psychiatric disorders and if assortment for psychopathology is primary or secondary to assortment for correlated variables. METHODS: A model for mate selection addressed whether the correlation between mates for psychiatric disorders arises from direct assortment (primary homogamy) or through correlation with other variables for which assortment occurs (secondary homogamy) or through cross-variable assortment. The model accounted for within-person co-morbidity as well as across-spouse data. RESULTS: Findings suggested that a moderate degree of assortment exists both within and across psychiatric diagnoses. Only a small amount of the observed marital resemblance for mental illness could be explained by assortment for correlated variables such as age, religious attendance and education. Similar results were obtained for the two samples separately and confirmed in their joint analysis, revealing that the co-morbidity and assortment findings, except for the marital correlation for age, religious attendance and education, replicate across samples. CONCLUSIONS: Significant but moderate primary assortment exists for psychiatric disorders. The bias in twin studies that have ignored the small amount of assortment is negligible.  相似文献   
992.
993.
The asymmetry of the aortic valve and aortic root may influence their biomechanics, yet was not considered in previous valve models. This study developed an anatomically representative model to evaluate the regional stresses of the valve within the root environment. A finite-element model was created from magnetic-resonance images of nine human valve-root specimens, carefully preserving their asymmetry. Regional thicknesses and anisotropic material properties were assigned to higher-order elastic shell elements representing the valve and root. After diastolic pressurization, peak principal stresses were evaluated for the right, left, and noncoronary leaflets and root walls. Valve stresses were highest in the noncoronary leaflet (538 kPa vs right 473 kPa vs left 410 kPa); peak stresses were located at the free margin and belly near the coaptation surfaces (averages 537 and 482 kPa for all leaflets, respectively). Right and noncoronary sinus stresses were 21% and 10% greater than the left sinus. In all sinuses, stresses near the annulus were higher than near the sinotubular junction. Stresses vary across the valve and root, likely due to their inherent morphologic asymmetry and stress sharing. These factors may influence bioprosthetic valve durability and the incidence of isolated sinus dilatation.  相似文献   
994.
995.
PATIENTS AND METHODS: We conducted a randomized, multicenter study of intravenous cyclophosphamide 500 mg/m2 plus fluorouracil 500 mg/m2 combined with either mitoxantrone (Novantrone, Lederle Cyanamid Canada Ltd, Willowdale, Ontario) 10 mg/m2 (CNF) or doxorubicin (Adriamycin, Adria Laboratories of Canada Ltd, Mississauga, Ontario) 50 mg/m2 (CAF) every 3 weeks in advanced breast cancer. RESULTS: The response rate in 249 randomized patients was 36% with CNF (44 of 121) and 48% with CAF (62 of 128) (P = .054), with complete remissions in 10 patients (8.3%) on CNF and in 13 (10.2%) on CAF. If only fully assessable patients are considered, the response rate was 48% (44 of 91) with CNF and 60% (62 of 103) with CAF (P = .098). At time of analysis, all except 10 patients (one CNF and nine CAF) had died. The median survival time with CAF was longer than with CNF (15.2 v 10.9 months; P = .003), and time to progression was also longer with CAF (5.3 v 3.2 months; P < .03). Survival differences remained significant (P = .006) if patients who failed to meet all eligibility criteria were excluded. Favorable prognostic factors for survival in a Cox regression model included good performance status (P < .0001); less than two organ systems involved by tumor (P < .0001); no involvement of lung, liver, or brain (P < .003); involvement of bone or bone marrow (P < .009), prior surgery for breast cancer (P < .006); being premenopausal (P < .03); > or = 3 years from diagnosis until randomization on this study (P < .03); and treatment with CAF (P < .03). Alopecia > or = grade 3 was reported in 55% of patients with CAF and 12% of patients with CNF (P < .001), while other > or = grade 3 toxicities did not differ significantly. Priestman-Baum quality-of-life assessment was comparable on the two study arms. CONCLUSION: In patients with advanced breast cancer, CAF was associated with longer survival than was CNF, with an increase in alopecia, but not in other toxicities.  相似文献   
996.
Mucus hypersecretion is a common characteristic of asthma. Acute severe asthma is often associated with neutrophilic infiltration into airways. Neutrophils contain elastase, a potent secretagogue in airways. Therefore, we hypothesized that instillation of ovalbumin in sensitized guinea pigs causes goblet cell secretion by releasing elastase from recruited neutrophils. When we instilled ovalbumin into the trachea of ovalbumin-sensitized guinea pigs, early recruitment of neutrophils identified by 3,3'- diaminobenzidine staining, and goblet cell degranulation measured with a semiautomatic computer-based imaging system occurred. The Leumedin NPC 15669 (a drug that inhibits leukocyte recruitment) and an antibody to intercellular adhesion molecule-1 (ICAM-1) both prevented neutrophil recruitment and goblet cell degranulation, implicating leukocytes in the response. Using immunofluorescence we showed that the leukocytes recruited early after antigen challenge were CD-16-positive, implicating neutrophils. Pretreatment with the selective neutrophil elastase inhibitor ICI 200,355 also prevented ovalbumin-induced goblet cell degranulation, implicating elastase. We conclude that ovalbumin-induced goblet cell degranulation is due to neutrophil recruitment and elastase release.  相似文献   
997.
This report summarizes results from an initial clinical evaluation of radioimmunodetection (RAID) in patients with pancreatic cancer using murine monoclonal antibody Nd2, directed against mucins from pancreatic cancer. Nd2 (2 mg) was labeled with 111In (2 mCi) and injected into 19 patients suspected of having pancreatic cancer. Planar scintigrams were taken 3 days post-infusion. As for final diagnoses after surgery, 14 cases were pancreatic cancer, and one case each was chronic pancreatitis, neurilemmoma, islet cell carcinoma, cholangioma, and apparent absence of suspected recurrent lesion of pancreatic cancer. Of 14 patients with pancreatic cancer, RAID was positive in 10 cases (71.4%). Cases other than pancreatic cancer were all negative, so the specificity was 100%. These results demonstrate that RAID using 111In-Nd2 can be useful in differentiating exocrine pancreatic cancer from benign conditions and other types of carcinomas in the pancreatoduodenal regions.  相似文献   
998.
In viral meningitis the inflammatory response involves activated T cells and monocytes which are recruited into the subarachnoid space. To identify the chemotactic signals attracting the cells to the site of infection in the meninges, we measured the levels of two CXC chemokines, interferon-gamma (IFN-gamma) inducible protein (IP)-10 and monokine induced by IFN-gamma, four CC chemokines, monocyte chemotactic protein (MCP)-1, RANTES, macrophage inflammatory protein (MIP)-1 alpha and MIP-1 beta, as well as the cytokines interleukin (IL)-15 and IL-16 in the cerebrospinal fluid (CSF) of patients suffering from viral meningitis. The results point to an involvement of two chemokines, MCP-1 and IP-10, since (1) unlike the other cytokines, MCP-1 and IP-10 were present in 97% and 79% of the CSF, respectively, at concentrations sufficient to induce chemotaxis of mononuclear cells; (2) more than 90% of the CSF of viral meningitis induced chemotaxis of peripheral blood mononuclear cells (PBMC) and all of them induced chemotaxis of activated T cells, and (3) the CSF-mediated chemotaxis of PBMC was inhibited by anti-MCP-1 antibodies and chemotaxis of activated T cells was abolished by the combination of anti-MCP-1 and anti-IP-10 antibodies. Our data provide evidence that MCP-1 and IP-10 lead to accumulation of activated T cells and monocytes in the CSF compartment in viral meningitis.  相似文献   
999.
1000.
Chitin, the second most abundant polysaccharide on earth, is degraded by chitinases and chitobiases. The structure of Serratia marcescens chitobiase has been refined at 1.9 A resolution. The mature protein is folded into four domains and its active site is situated at the C-terminal end of the central (beta alpha)8-barrel. Based on the structure of the complex with the substrate disaccharide chitobiose, we propose an acid-base reaction mechanism, in which only one protein carboxylate acts as catalytic acid, while the nucleophile is the polar acetamido group of the sugar in a substrate-assisted reaction. The structural data lead to the hypothesis that the reaction proceeds with retention of anomeric configuration. The structure allows us to model the catalytic domain of the homologous hexosaminidases to give a structural rationale to pathogenic mutations that underlie Tay-Sachs and Sandhoff disease.  相似文献   
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