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81.
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To date, only one complete genome screen for obsessive-compulsive disorder (OCD) has been published. That study identified a region of suggestive linkage (maximum lod score of 2.25) with a relatively small sample size (N = 56; 27 with OCD). Additional complete genome screens are needed to confirm this finding and identify other regions of linkage. We present the clinical characteristics and power to detect linkage of 11 multigenerational families with OCD and hoarding (N = 92; 44 with OCD), as well as heritability estimates for several quantitative traits. Families with at least two individuals with OCD were identified through probands with childhood-onset OCD. Expected lod scores were calculated for simulated genetic marker data under an additive and two dominant models assuming a dense SNP marker map. All affected individuals had an early age of onset (18 or younger). Hoarding was present in 46% of subjects. Obsessive-compulsive symptoms and hoarding were highly heritable. The maximum mean expected lod score was 3.31 for OCD and 1.39 for hoarding. We found reasonable power to detect regions of interest (lod = 2) for OCD in these families, but will need to expand our family collection to have adequate power to detect regions of interest for hoarding.  相似文献   
83.
Targeted therapy comes of age in scleroderma   总被引:3,自引:0,他引:3  
Systemic sclerosis (SSc, also known as scleroderma) has the highest case-specific mortality among the rheumatic diseases; however, advances in understanding of pathogenesis and an appreciation of the clinical heterogeneity of this disease, together with therapeutic advances in other areas, have raised the possibility of substantial improvements in its management. Key areas of advance include the development of clinical and laboratory methods for early detection of complications and the integration of vascular, immunomodulatory and antifibrotic therapies. Disease models have facilitated the identification of key mediators or processes that could be targeted therapeutically and have provided a platform for preclinical testing of novel candidate therapies. This review will consider current clinical aspects of SSc and the emergence of targeted therapy that is linked to key pathogenic processes or that targets pivotal mediators.  相似文献   
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Cloning and analysis of the murine Fanconi anemia group C cDNA   总被引:7,自引:1,他引:7  
Fanconi anemia (FA) is one of a group of disorders characterizedat the cellular level by a combination of hypersensitivity toDNA-damaging agents, chromosomal instability, and defectiveDNA repair. Clinical features of FA include pancytopenia, oftenaccompanied by specific congenital malformations, and a predispositionto leukemia. Since the hematological manifestations are thecritical defect in terms of prognosis, FA is a candidate diseasefor gene replacement therapy, and the development of a mousemodel system is essential for the initial stages of this work.Previously, we have cloned the gene defective in FA group Cby complementation of the intrinsic sensitivity of FA cellsto DNA cross-linking agents. We have now cloned the murine homologueof the human FACC cDNA. The mouse cDNA (Facc) shares 79% aminoacid sequence similarity with the human gene product. The expressionof the mouse cDNA in human FA(C) cells restores the cellulardrug sensitivity to normal levels. Thus, the function of theprotein has been conserved despite the significant sequencedivergence. PCR analysis of mouse tissue RNA reveals that thegene is expressed in all adult tissues, while in situ RNA hybridizationexperiments show tissue specific expression at late stages offetal development. Cross-hybridizing sequences exist in DNAfrom other mammals, chicken and Drosophila. These results supportthe hypothesis that the FACC gene product has a role in a basicaspect of cellular protection against DNA damaging agents andthat this function has been conserved during evolution.  相似文献   
87.
Isolation of rhinoviruses and coronaviruses from 38 colds in adults   总被引:10,自引:0,他引:10  
Nasal washings were collected from 27 normal adults during 38 naturally acquired colds. The washings were exhaustively tested using tissue cultures, organ cultures and electron microscopy. Washings yielding no identifiable agent were inoculated into human volunteers, and further specimens obtained from the latter were examined by the same techniques in vitro. Viruses were identified in association with 25 of the original 38 colds (65.7%). Fifteen were rhinoviruses (39.5%), seven coronaviruses (18.4%), two were para-influenza viruses, and one was influenza virus. Use of organ cultures and of volunteers significantly increased the isolation rate. No agent was cultivated from the remaining 13 specimens, although tests in volunteers showed that cold-producing agents were present in five of them (13%). Three specimens gave doubtful results in volunteers, and five others, all collected within a period of six weeks in December and January, apparently contained no infectious agent.  相似文献   
88.
Researchers have hypothesized that compulsive checkers suffer from impairment in explicit memory (e.g., Sher, Frost, & Otto, 1983 ), low confidence in explicit memory (e.g., McNally & Kohlbeck, 1993 ), or both. However, empirical findings have been equivocal, possibly due to variability in effect sizes produced by small samples. Combining data across studies may yield more meaningful conclusions than can be surmised from a narrative review. Following a brief review of the literature on checking and memory, we present meta-analytic results suggesting that checkers are impaired on many types of memory tasks (e.g., verbal free recall, verbal cued recall, and recall of actions) and are less confident in recognition than noncheckers. We discuss implications of these findings, suggestions for future research, and limitations of this analysis.  相似文献   
89.
Comorbidity measurements have recently been used to improve estimation of tolerance to allogeneic hematopoietic cell transplantation (HCT). We sought to determine the independent effect of comorbidity and performance status on HCT outcome and to devise a simple risk classification system for transplant-related mortality. We analyzed 105 consecutively enrolled patients who underwent HCT and received reduced intensity conditioning with fludarabine, melphalan, and alemtuzumab. Comorbid conditions were tabulated using 2 scales, the Charlson Comorbidity Index (CCI) and the Kaplan-Feinstein Scale (KFS). Comorbid conditions were found in 47% of patients by the KFS and in 27% by the CCI (P < .001). Using the Eastern Cooperative Oncology Group Performance Status (PS) scale, 34% had a PS score >0 (range, 0-2). A simple scale combining the KFS and PS enabled separation of high- from low-risk patients, with 6-month cumulative incidences 50% and 15%, respectively for transplant-related mortality (P = .001) and enhanced prognostic power over the CCI alone (P = .018). Prospective studies evaluating more comprehensive functional and comorbidity measurements are warranted.  相似文献   
90.
We have used a genetic approach to study the differentiation of B lymphocytes. The cultured murine cell line 70Z/3 resembles pre-B cells in containing the heavy chain of the immunoglobulin IgM, , as an internal protein in the absence of light chain, L. However, overnight incubation with the B cell mitogen lipopolysaccharide (LPS) induces the cells to mature to a B lymphocyte-like state by the induction of L chain synthesis and the appearance of IgM on the cell surface. We have used immunoselection against surface-bound IgM to isolate LPS uninducible variants of 70Z/3. These fall into two complementation groups, LPS A and LPS B. LPS A variants predominated and were found at a frequency of 1/1200. These cells were completely unresponsive to LPS. LPS B was represented by a single variant in which a subset of cells was induced to display wild-type levels of membranebound IgM, and the proportion of induced cells increased with prolonged incubation with LPS. We detected no structural defects in either variant group, but LPS B may represent a defect in the decision to differentiate in response to LPS.  相似文献   
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