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21.
Archives of Sexual Behavior - Sex is integral to maintaining a satisfying long-term romantic relationship such as marriage. It is thus important to identify the factors that promote sexual...  相似文献   
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Summary The recognition of recurring sites of chromosome changes in malignancies has greatly facilitated the identification of genes implicated in the pathogenesis of human cancers. Based especially upon recent studies [1–4], it appears increasingly likely that a subset of recurring chromosome alterations will be recognized in human breast cancer. Currently recognized chromosome changes characterizing breast carcinoma include the recognition of cytologic features of gene amplification (e.g. double minutes [dmins] and homogeneously staining regions [HSRs]) [5–8]. As these and other chromosome regions are implicated in recurring abnormalities in breast cancer, it will become increasingly important to have band-or region-specific genomic libraries and probes in order to facilitate high resolution physical mapping and ultimately to clone breast cancer related genes [9]. Toward this end an important recent development in physical mapping has been the establishment of chromosome microdissection as a rapid and reproducible approach to rapidly isolate and characterize chromosome region-specific DNA, greatly facilitating the initial steps in positional cloning of disease-related genes [10–13]. In this brief report, we will highlight the application of chromosome microdissection to the generation of region-specific probes for both fluorescent in situ hybridization (FISH) and the generation of genomic microclone libraries. Additionally, efforts using this methodology to generate a microclone library encompassing the early onset breast/ovarian cancer (BRCA1) gene will be presented.Presented by Jeffrey M. Trent at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer.  相似文献   
24.
Clozapine has been reported to improve selected aspects of cognitive function in neuroleptic-resistant schizophrenia. In this study, we report the first direct comparison of the effect of clozapine and typical neuroleptic drugs on cognitive function in neuroleptic-responsive schizophrenia. Sixty-four patients with recent onset, neuroleptic-responsive schizophrenia or schizoaffective disorder were randomly assigned to either clozapine (n = 35) or typical neuroleptics (n = 29) and followed for 12 months. They were administered a comprehensive cognitive test battery at baseline and at 6 weeks, 6 months and 12 months after initiating drug treatment. Treatment with clozapine improved psychomotor speed and attention [Digit Symbol Substitution Test (DSST)] and verbal fluency [Category Instance Generation and Controlled Word Association Test (CWAT)] at 6 weeks. The improvement in these measures was maintained throughout the 12-month period. Treatment with typical neuroleptics produced no sustained improvement in any cognitive measure, except for a tendency to improve delayed recall memory (Verbal List Learning Test). The improvement in the DSST and CWAT was significantly greater with clozapine treatment compared to that with typical neuroleptics. These improvements were not related to improvement in psychopathology. These results suggest that clozapine is superior to typical neuroleptics in improving specific types of cognitive function in recent onset, neuroleptic-responsive schizophrenia.  相似文献   
25.
Echocardiographic left ventricular mass (LVM) estimates are strong predictors of subsequent mortality and cardiovascular events. It is known that blood pressure (BP), weight (WT), and age are significantly correlated with LVM. We hypothesized that stroke volume (SV) measured by Doppler echocardiography would also be correlated with LVM. Two hundred and thirteen patients referred for routine echocardiography had determination of LVM, cuff BP, and Doppler SV. Those with localized LV disease, valvular disease, or cor pulmonale were excluded. In both men and women, systolic BP (SBP) was more closely correlated with LVM than was diastolic blood pressure or mean arterial pressure, and SV was more closely correlated with LVM than cardiac output or cardiac index. Stepwise regression, followed by multiple regression showed that four variables (WT, SV, SBP, and AGE) explained 32.3% of the variability in LVM in men and 48.5% of the variability in LVM in women. WT and SV were significant determinants of LVM in both men and women. Age was also significant in men and SBP was also significant in women. For both men and women, SV was more significantly correlated with LVM than was SBP. The changes in LVM associated with 1 SD increments of SV and SBP, respectively, were 8 and 5 g for men and 13 and 11 g for women. We conclude that men and women have different patterns of variables influencing LVM. Doppler echocardiographic SV is a newly described determinant of LVM that has a greater correlation with LVM than does SBP. This study reemphasizes the importance of WT as the major determinant of LVM. (ECHOCARDIOGRAPHY, Volume 13, January 1996)  相似文献   
26.
There have been many reports of probable lithium-induced organic brain syndromes occurring when serum lithium levels are within or close to the therapeutic range. The authors report on five patients who developed clinical syndromes suggestive of severe neurotoxicity during lithium treatment. In all cases lithium levels were between .75 and 1.7 mEq/liter. The patients who developed neurotoxicity had markedly higher global ratings of psychotic symptomatology and anxiety in the pretoxic period than did patients who never deveoped neurotoxicity. When the acute manic state is characterized by marked psychotic symptoms and intense anxiety, it may be associated with increased vulnerability to the development of severe lithium neurotoxicity.  相似文献   
27.
Administration of imipramine plus serotonin (5-HT) to rats has been proposed as an animal model of Duchenne muscular dystrophy. We studied the skeletal muscle necrosis produced in male rats given 5-HT after pretreatment with imipramine, other tricyclic antidepressants, or antihistamines, which like the tricyclic antidepressants, can block neuronal reuptake of 5-HT. Following one of these agents plus 5-HT, 20 mg/kg subcutaneously (s.c.), necrosis was more severe in the soleus muscle than the quadriceps. There was no significant difference in the incidence of necrosis in the soleus and quadriceps muscles following one of these agents plus 5-HT, 100 mg/kg, intraperitoneally (i.p.). After one of these agents plus 5-HT i.p., but not 5-HT s.c., extensive necrosis was significantly more frequent and severe in the quadriceps muscle than after 5-HT s.c. Chlorpheniramine (CP) plus 5-HT, 2.5 mg/kg intravenously, produced less muscle necrosis than CP plus 5-HT s.c. or i.p. The necrosis produced by CP plus 5-HT s.c. was comparable ipsilateral and contralateral to the injection site. The necrosis following CP plus 5-HT i.p. was maximal at 24 hr and remained fairly constant until 5 days. Regeneration was prominent by 7 days. The muscle necrosis produced by CP plus 5-HT is blocked by some 5-HT blockers, e.g., methiotepin and methysergide. It is also partially blocked by denervation. The capacity of tricyclic antidepressants and antihistamines to block neuronal 5-HT reuptake tended to be negatively correlated with the capacity to potentiate the muscle necrosis they produced with 5-HT, which suggests that blockade of 5-HT uptake is not the mechanism of the pathology produced by the combined treatment. The tricyclic antidepressants and the antihistamines are "membrane stabilizers-labilizers". Other drugs which are "membrane stabilizers-labilizers" such as trihexyphenidyl and procaine also promoted skeletal muscle necrosis when given prior to 5-HT. It is proposed that the effects of imipramine plus 5-HT on skeletal muscle are not due to the blockade of neuronal uptake of 5-HT and subsequent vascular-induced ischemia, but reflect direct toxic effects of these agents on skeletal muscle.  相似文献   
28.
OBJECTIVE: The study examined the associations between several sociodemographic and psychosocial variables and unexplained chronic fatigue in the community before and after adjustment for psychiatric morbidity and determined the prevalence of fatigue and rate of disability resulting from fatigue in the general population. METHOD: The study is a secondary analysis of 1993 data from a household survey of psychiatric morbidity conducted by the Office for Population Censuses and Surveys in Great Britain. The survey included 12,730 subjects age 16-64 years. Unexplained chronic fatigue was used as the dependent variable in a logistic regression analysis, with various sociodemographic and psychosocial variables and psychiatric morbidity as the independent variables. Psychiatric morbidity was assessed by using the Revised Clinical Interview Schedule. Fatigue was measured by using the fatigue section of the Revised Clinical Interview Schedule. RESULTS: A total of 10,108 subjects agreed to cooperate (79.4% participation rate). The prevalence of unexplained chronic fatigue was 9%. Subjects with psychiatric morbidity had higher rates of fatigue. Adjustment for psychiatric morbidity had a minor effect on the associations between sociodemographic factors and chronic fatigue. After adjustment, older subjects, women, and couples with children had higher rates of fatigue. Single subjects, widowed subjects, adults living with parents, and economically inactive subjects had lower rates of fatigue. Fatigue was associated with considerable disability, but most of this disability was explained by the association between fatigue and psychiatric morbidity. CONCLUSIONS: Unexplained chronic fatigue is a common condition, strongly associated with psychiatric morbidity. The close relationship between fatigue and psychiatric morbidity should not obscure the possibility of differences as well as similarities in their etiologies.  相似文献   
29.
Sarcomas--like leukemias, which are also mesodermal malignancies--carry biological significance disproportionate to their clinical frequency. Identification of mutations and translocations associated with these tumors has illuminated aberrant signaling pathways that cause these diseases, determine their behavior, and are therapeutic targets. Activated receptor-associated tyrosine kinase c-kit, mutated in most gastrointestinal stromal tumors, has proven a clinically effective target for enzyme inhibition. A translocation involving a single gene family, consisting of EWS and related genes, has been identified in five different sarcomas, and its chimeric protein products could prove similarly amenable to inhibitors. Resolution of the histopathological complexity is being aided by data from molecular and chromosomal characterization. Improvements in imaging, definition of prognostic factors, and surgical and radiotherapeutic treatment have resulted in improved local control. Continued progress will depend on further adapting the rapidly evolving technologies of genomics and proteomics. It will also depend upon accurate histopathological diagnosis based on validated reagents and consistent methodologies applied to adequate tissue samples derived from patients with complete clinical data. Finally, multicenter, coordinated trials, such as those that occurred with assessment of imatinib mesylate in metastatic gastrointestinal stromal tumors, will assure the most rapid reductions in morbidity and mortality.  相似文献   
30.
Mutations in the transforming growth factor beta type II receptor (TGFbetaRII) gene have been detected in several human cancer types exhibiting microsatellite instability. Using intron primers previously reported for examination of the entire coding region of the TGFbetaRII gene, 29 sporadic gastric cancers were screened with non-radioactive single strand conformation polymorphism and subsequent DNA sequencing analysis. Mutations of the TGFbetaRII gene were detected in three out of 29 tumors (10%). Two cases showed deletions in a polyadenine tract in both alleles and was positively associated with replication error. One case had an insertion of GA dinucleotide sequence in one allele. Mutations of the TGFbetaRII gene were restricted to exon 3 and other coding regions were not affected. Loss of heterozygosity was detected by analyzing a polymorphic site in intron 2. Three out of nine (33%) informative cases, which were all of intestinal type and advanced cases, showed loss of heterozygosity but neither TGFbetaRII mutation nor replication error was found in these cases. Immunoreactivity of TGFbetaRII in tumor tissues was reduced to a different extent in the gastric cancer with genetically abnormal transforming growth factor. Although the numbers studied are small, homozygous (A)10 deletion or loss of heterozygosity of TGFbetaRII is involved in tumorigenesis and progression of at least some part of sporadic gastric cancer.   相似文献   
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