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31.
A prospective study of dehydroepiandrosterone sulfate, mortality, and cardiovascular disease 总被引:12,自引:0,他引:12
It has been postulated that dehydroepiandrosterone (DHEA) and its sulfate ester, dehydroepiandrosterone sulfate (DHEAS), the major secretory products of the human adrenal gland, may be discriminators of life expectancy and aging. We examined the relation of base-line circulating DHEAS levels to subsequent 12-year mortality from any cause, from cardiovascular disease, and from ischemic heart disease in a population-based cohort of 242 men aged 50 to 79 years at the start of the study. Mean DHEAS levels decreased with age and were also significantly lower in men with a history of heart disease than in those without such a history. In men with no history of heart disease at base line, the age-adjusted relative risk associated with a DHEAS level below 140 micrograms per deciliter was 1.5 (P not significant) for death from any causes, 3.3 (P less than 0.05) for death from cardiovascular disease, and 3.2 (P less than 0.05) for death from ischemic heart disease. In multivariate analyses, an increase in DHEAS level of 100 micrograms per deciliter was associated with a 36 percent reduction in mortality from any causes (P less than 0.05) and a 48 percent reduction in mortality from cardiovascular disease (P less than 0.05), after adjustment for age, systolic blood pressure, serum cholesterol level, obesity, fasting plasma glucose level, cigarette smoking status, and personal history of heart disease. Our conclusions are limited by the single determination of DHEAS levels, but the data suggest that the DHEAS concentration is independently and inversely related to death from any cause and death from cardiovascular disease in men over age 50. 相似文献
32.
Cytochrome P450 1A1 and manganese superoxide dismutase genes polymorphisms in ankylosing spondylitis
OBJECTIVES: To investigate the associations of cytochrome p450 1A1 (CYP1A1) and manganese superoxide dismutase (MnSOD) genes polymorphisms with the susceptibility to AS in Taiwan. METHODS: The polymorphisms of CYP1A1 and MnSOD genes were determined in 70 patients with ankylosing spondylitis (AS) and 93 healthy controls by polymerase chain reaction (PCR)/restriction fragment length polymorphisms (RFLP) methods. RESULTS: The genotype frequency of CYP1A1 4887C/A was significantly lower in patients with AS than in controls. The phenotype frequency of CYP1A1 4887A also tended to be decreased in patients with AS. There were no significant differences in the genotype, allele, and phenotype frequencies of MnSOD gene polymorphisms between patients with AS and controls. CONCLUSION: CYP1A1 4887A may be a protective factor for the development of AS in Taiwan. However, MnSOD gene polymorphisms are not associated with the susceptibility to AS. 相似文献
33.
This study compared depressive symptomatology among Chinese psychiatric outpatients versus the general Chinese population, and across 3 cultural groups--Chinese, Chinese American, and Caucasian American students--by use of the Center for Epidemiological Studies-Depression Scale (CES-D; L. S. Radloff, 1977) and the Chinese Depression Scale (N. Lin, 1989), translated from the CES-D. Results indicate that Chinese patients (n = 112) endorsed a higher proportion of somatic symptoms than nonpatients (n = 112). The intercultural comparison found that Chinese students (n = 98) had the lowest levels of somatic depressive symptom endorsement compared to both U.S. groups (n = 198). These findings seem to suggest that the tendency toward somatic symptom reporting is not any greater among Chinese populations but may be a function of having a mental illness or of help seeking in China. 相似文献
34.
Chlamydia trachomatis is an obligate intracellular parasite of eucaryotic cells. Little is known about the role of the host in supporting chlamydial replication beyond the facts that host cells provide ATP and that de novo host protein synthesis is not required for bacterial growth. To further explore potential contributions of host nuclear function to chlamydial development, we questioned whether murine C. trachomatis could grow in mouse L cells that had been enucleated with cytochalasin B. Following enucleation, cells were infected with chlamydiae and analyzed morphologically and biochemically. Late in infection, substantial numbers of chlamydiae of all developmental stages were seen within large cytoplasmic inclusions that were indistinguishable from those seen in infected intact cells. Normal numbers of infectious progeny particles were produced from enucleated cultures. We conclude that active host cell nuclear function is not required to support the growth of chlamydiae. 相似文献
35.
H.-H. Wang L.-N. Liao C.-L. Lin L.-L. Yen Y.-M. Hsiao J.-L. Ko 《Transfusion Clinique et Biologique》2021,28(1):44-50
BackgroundPlatelet transfusion is required to treat haemo-oncology or trauma patients. Platelet apheresis (PA) performed with apheresis equipment has increased rapidly in recent years. Leucocyte-reduced platelet apheresis (LRPA) can reduce the risk of platelet refractoriness and febrile nonhemolytic transfusion reactions (FNHTRs) for transfusion. Accordingly, this study aimed to investigate and compare the platelet metabolic and functional responses between PA performed with Haemonetics and LRPA performed with Trima Accel cell separator.MethodsThe qualities of platelets collected through PA and LRPA were evaluated in terms of visual appearance, morphology, platelet-aggregation changes, metabolic activities, and bacterium-screening test during 5-day storage. Statistical analyses included two-sample t-test and generalised estimating equation(GEE) method.ResultsDuring 5-day storage in LRPA, residual leucocytes were all <1.0×106, and the parameters of platelet function were as follows: platelet aggregated to agonists such as adenosine 5′-diphosphate (ADP) and collagen, and the extent of shape change and pO2 showed no statistically significant difference between PA and LRPA. The hypotonic shock reaction (HSR) on days 0, 1, and 3 were significantly higher in LRPA than in PA (71.78±6.92 vs. 64.10±7.42; P=0.002; 71.53±8.98 vs. 62.96±9.84; P=0.007; 68.05±7.28 vs. 57.76±6.80; P<0.0001, respectively). Values of mean platelet volume (MPV) were statistically larger in PA than in LRPA on days 0, 1, and 3. On day 5, the swirling score was higher in LRPA than in PA. The mean lactate levels had no statistically significant difference between PA and LRPA. Moreover, no growth was observed through bacterium-screening test conducted on 40 samples.ConclusionComparison of LRPA and PA products collected from the Trima Accel and Haemonetics automated blood-collection systems, respectively, revealed that both products possessed good platelet qualities even though additional processes are needed to reduce leucocytes. Furthermore, investigating the outcomes of other apheresis instruments with focus on the safety of donors, products, and recipients is necessary. 相似文献
36.
N Weidner K R Geisinger R T Sterling T R Miller T S Yen 《American journal of clinical pathology》1986,85(4):395-401
Five cases of benign lymphoepithelial cysts (BLCs) of the parotid gland are reported, and the histologic, aspiration cytologic, and ultrastructural findings are described in detail. These uncommon parotid lesions contain epithelium-lined cystic spaces encased by abundant lymphoid tissue with germinal centers. The epithelium was "mucoepidermoid" in three of our cases and squamous in two. Familiarity with the morphologic features of BLCs should make it possible to distinguish them from similar-appearing cystic lesions, especially low-grade cystic mucoepidermoid carcinoma and cystic types of benign lymphoepithelial lesion (so-called Mikulicz's disease). These distinctions, however, are difficult on aspiration cytology specimens. 相似文献
37.
X-box binding protein 1 (XBP1) C--116G polymorphisms in bipolar disorders and age of onset 总被引:2,自引:0,他引:2
X-box binding protein 1 (XBP1), a critical gene in the endoplasmic reticulum stress response, is located on chromosome 22q12, which has been linked with bipolar disorders in several studies. Recently, associations have been reported between a polymorphism (-116C --> G) in the promoter region of XBP1, and bipolar disorders in both case-control study and family-based association study, however, this finding is not yet confirmed by other research using independent sample populations. To replicate this finding and determine the association between onset age of bipolar disorders and the XBP1 C--116G polymorphism, we investigated the prevalence of this polymorphism in a Chinese population (153 bipolar disorder patients and 174 controls). We were unable, however, to demonstrate a significant association between the C--116G polymorphism and bipolar disorders (P = 0.674 for genotype and P = 0.436 for allele frequency) or age at onset (P = 0.563). Further, no association was demonstrated between this polymorphism and family history in bipolar disorder patients. These negative findings suggest that the XBP1 C--116G polymorphism does not play a major role in the pathogenesis of bipolar disorders in Chinese populations. 相似文献
38.
The anatomy of the cardiac conduction system in normal and malformed hearts reconstructed from histological serial sections is reviewed. The sinus node and its arterial supply are located in the right superior cavoatrial junction except in hearts with left-sided juxtaposition of the atrial appendages, mirror-image, and isomeric arrangements of the atria. In the presence of normally positioned atrial and ventricular septal structures, the triangle of Koch is a useful guide to the location of the atrioventricular node and the penetrating bundle. In hearts with isolated ventricular septal defects, it is necessary to distinguish between a perimembranous defect and a muscular inlet defect. The conduction axis runs in the area of fibrous continuity at the posteroinferior edge of a perimembranous defect but in the anterosuperior rim of a muscular inlet defect. In most hearts with tetralogy of Fallot, the danger area is the region of aortic-mitral-tricuspid fibrous continuity where the axis penetrates. In hearts with atrioventricular septal defects, the lack of contiguity between atrial and ventricular septum results in a posterior displacement of the nodal triangle and coronary sinus and an elongation of the nonbranching bundle. Hearts with abnormally located atrioventricular nodes and conduction axes are mainly those with atrioventricular discordance, ambiguous atrioventricular connection in presence of left-hand pattern ventricular topology, hearts with univentricular atrioventricular connection to a morphologically left or indeterminate ventricle, and hearts with a straddling tricuspid valve. The location of the atrioventricular node is governed by the orientation of the ventricular septum and by the pattern of ventricular topology.
Supported by the British Heart Foundation. 相似文献
Resumen Se revisa la anatomía del sistema de conducción cardiaca en los corazones normales y con malformaciones a la luz de la reconstrucción a partir de cortes histológicos seriados. El nódulo sinusal y su irrigación arterial está ubicado en la unión cavoatrial derecha, excepto en corazones con yuxtaposición izquierda de las auriculillas o con alteraciones en imagen en espejo e isoméricas de las aurículas. En presencia de estructuras septales atriales y ventriculares normalmente ubicadas, el tríangulo de Koch es una guía útil para la localización del nódulo atrioventricular y la penetración del haz. En corazones con defectos septales ventriculares aislados es necesario distinguir entre un defecto perimembranoso y un defecto del tracto muscular de entrada. El haz de conducción avanza en el área de continuidad fibrosa sobre el borde posteroinferior de un defecto perimembranoso, en el filo anterosuperior de un defecto del tracto muscular de entrada. En la mayoría de los corazones con tetralogía de Fallot el área de peligro se encuentra en la región del trígono fibroso aórticomitral y tricuspídeo sobre el cual penetra el haz de conducción. En corazones con defectos septales atrioventriculares la falta de continuidad entre el septo atrial y el ventrícular resulta en un desplazamiento posterior del triángulo de Koch y del seno coronario y en una elongación del haz no ramificado. Corazones con nódulos atrioventriculares y haces de conducción anormalmente ubicados son principalmente aquellos con discordancia atrioventricular, con conexión atrioventricular ambigua en presencia de un patrón izquierdo de arquitectura ventricular, corazones con conexión atrioventricular univentricular a un ventrículo morfológicamente izquierdo o indeterminado y corazones con válvula tricuspídea cabalgante. La ubicación del nódulo atrioventricular está determinada por la orientación del septo ventricular y por el patrón de la arquitectura ventricular.
Résumé L'anatomie du système de conduction du coeur normal et du coeur siège de malformations reconstituée à partir de coupes sériées histologiques est exposée. Le sinus nodal et sa vascularisation sont situés au niveau de la partie supérieure de la jonction auriculo-ventriculaire droite sauf dans certains cas: coeur avec juxtaposition des auricules du côté gauche, image en miroir et dispositions isomères des oreillettes. Lorsque les cloisons auriculaire et ventriculaire occupent une situation normale, le triangle de Koch constitue un repère utile pour localiser le noyau auriculo-ventriculaire et le faisceau de His. En cas de défects septaux ventriculaires isolés, il est nécessaire de distinguer les défects périmembraneux et les défects musculaires. L'axe nerveux conducteur chemine dans la zone de continuité fibreuse au bord postéroinférieur du défect périmembraneux mais il chemine au bord antéro-supérieur du défect musculaire. En cas de tétralogie de Fallot, le danger se situe souvent au niveau de la zone fibreuse de continuité aortique-mitrale-tricuspide où pénètre l'axe conducteur. En cas de coeur porteur d'un défect septal auriculo-ventriculaire, le défaut de continuité entre la cloison ventriculaire et la cloison auriculaire entraîne le déplacement postérieur du triangle nodal et du sinus coronaire ainsi que l'élongation du faisceau. Les coeurs qui présentent une anomalie du siège des noyaux auriculo-ventriculaires et des nerfs conducteurs sont principalement ceux qui sont le siège d'une anomalie auriculo-ventriculaire, d'une connexion auriculo-ventriculaire ambiguë en cas d'une disposition ventriculaire de type gauche, d'une connexion auriculo-ventriculaire univentriculaire avec une morphologie ventriculaire gauche ou indeterminée, d'une valve tricuspide en fourche. Le siège du noyau auriculo-ventriculaire est fonction de l'orientation du septum ventriculaire et de l'architecture ventriculaire.
Supported by the British Heart Foundation. 相似文献
39.
The protective effect of "San-fang-feng" derived from the root of Echinops grijsii Hance on CCl4-induced hepatotoxicity has been studied. This crude drug was found to possess a marked hepatoprotective effect. A comparison of the protective effect with "Lou-lu" derived from the root of E. latifolius Tausch and "Pei-chai-hu" original Bupleurum chinense showed that E. grijisii and E. latifolius were more effective than B. chinense as reported previously. The results suggested that both E. grijisii and E. latifolius could correct the hepatocyte necrosis and functional disorder induced by the CCl4 treatment. 相似文献
40.
Laparoscopically assisted full thickness skin graft for reconstruction in congenital agenesis of vagina and uterine cervix 总被引:1,自引:0,他引:1
Lee CL Wang CJ Liu YH Yen CF Lai YL Soong YK 《Human reproduction (Oxford, England)》1999,14(4):928-930
In patients with agenesis of the vagina and cervix but with a functional endometrium, the traditional treatment is hysterectomy with construction of a neovagina. We report successful treatment by laparoscopically assisted full thickness skin graft for reconstruction in a patient with congenital agenesis of the vagina and uterine cervix concomitant with haematometra and ovarian endometrioma in a 12 year old girl. Postoperatively, the vaginal skin graft healed well, and menstruation first appeared 4 weeks later. In our opinion, a combined laparoscopic and vaginal procedure with full thickness skin graft is an efficacious alternative in managing such genital defects. 相似文献