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991.
Kenneth S. Kendler Ellen E. Walters Kim R. Truett Andrew C. Heath Michael C. Neale Nicholas G. Martin Lindon J. Eaves 《Behavior genetics》1995,25(6):499-515
Self-report symptoms of anxiety are widely used in mental health and social science research as an index of current psychiatric
state. Previous twin studies have suggested that genetic factors account for a significant proportion of the variance in these
symptoms. To replicate and extend these findings, we examined self-report symtoms of panic-phobia and somatization in the
“Virginia 30,000” twin-family sample. Model fitting applied to 80 unique relationships in the twin-family pedigree produced
the following major results: (i) genetic effects were significant for both symptom factors, accounting for between 25 and
49% of the total variance, with the exception of symptoms of panic-phobia in females, where they accounted for 15–16% of the
variance; (ii) familial environmental effects were absent for symptoms of somatization, while for symptoms of panic-phobia
they accounted for a very small proportion of variance in males (≤1.2%) and a modest proportion in females (6–17%) (iii) spousal
correlations were present for both factors, ranging from +0.05 to +0.20; (iv) genetic factors which influenced symptoms were
generally the same in males and females, although their effect was greater in males; (v) heritability estimates were lower
in the population-based than in the volunteer sample; and (vi) when test-retest reliability was included in the model, results
suggest that genetic factors account for at least half of the stable variance for all symptom factors, except panic-phobia
in females. Our results support the validity of previous twin studies of self-report symptoms of anxiety and suggest that
genetic factors significantly influence these symptoms but familial-environmental factors play little or no etiologic role. 相似文献
992.
Ethanol has various effects on male sexual activity under the influence of direct and indirect, in acute and chronic alcohol ingestion. However, whether acetaldehyde, a principal metabolite of ethanol, may affect penile erection directly has still not been elucidated. This present study was, therefore, designed to clarify the pharmacologic effects of the acetaldehyde on corpus cavernosal smooth muscle. Corpus cavernosal strips were prepared from rabbit penises. Isometric tension changes of rabbit corpus cavernosal strips to various drugs and electrical field stimulation (EFS) in an organ chamber were recorded with a pressure transducer after active muscle tone had been induced by phenylephrine (10(-5) mol/L). At the concentrations employed, acetaldehyde had no effect on the pH of the bathing medium. Acetaldehyde in each concentration did not significantly affect resting tone of the smooth muscle during 30 min incubation. Acetaldehyde suppressed contractility induced by phenylephrine and KCI at 10(-4) mol/L, and relaxation induced by EFS and bethanechol at 10(-3) mol/L and 10(-4) mol/L respectively, but acetaldehyde enhanced relaxation induced by ATP at high acetaldehyde level. Sodium nitroprusside-induced relaxation was not affected at any employed acetaldehyde concentration. This suggests that increasing the acetaldehyde level may contribute to male erectile dysfunction mainly by the inhibition of nitric oxide formation. 相似文献
993.
Increased expression of glucose transporter1 (GLUT1) has been reported in many human cancers. We hypothesized that the degree of GLUT1 might provide a useful biological information in gastric adenocarcinoma. RT-PCR and immunostaining were used to analyze GLUT1 expression in gastric cancer. RT-PCR showed GLUT1 expression was not largely detected in normal gastric tissue but was detected in cancerous gastric tissue of counterpart. By immunohistochemistry, GLUT1 protein was absent in normal gastric epithelium and intestinal metaplasia. 11 of 65 patients with gastric adenocarcinoma had specific GLUT1 immunostaining in a plasma membrane pattern with varied intensities. GLUT1 protein did not show any significant correlation with tumor stage and nodal metastasis (p>0.05 by Mann-Whitney test). However, the positive immunostaining for GLUT1 is associated with intestinal differentiation (p=0.003). Our results suggest that GLUT1 protein is associated with intestinal type of gastric cancer. 相似文献
994.
Two cases of chronic pancreatitis with pseudocyst complicated by obstructive jaundice 总被引:2,自引:0,他引:2
Cho HG Min HY Jang DS Shin YW Kwon KS Kim YS Kim MY Kim KR 《Yonsei medical journal》2000,41(4):522-527
We recently treated two cases of chronic pancreatitis with obstructive jaundice due to compression of the common bile duct by pancreatic pseudocyst. The two cases were males admitted with the complaint of icteric skin color. The first, a 46-year-old male, admitted with the complaint of icteric skin color. He was treated by operative cystojejunostomy after percutaneous drainage of the pseudocyst and percutaneous transhepatic biliary drainage. The other case was a 58 year-old male who admitted with the complaint of icteric skin color. He had an infected pseudocyst in the pancreas and was endoscopically treated. Both of them were discharged with favorable clinical course and normal laboratory findings after the treatment. The former patient remained well 11 months after treatment, but the latter patient died from necrotizing pancreatitis and septic shock 6 months after treatment. Most cases of obstructive jaundice associated with pseudocysts appear to be due to fibrotic stricture of the intrapancreatic portion of the common bile duct rather than due to compression of the bile duct by the pseudocyst. In a patient with secondary pancreatic infection or obstructive jaundice following pancreatic disease, differentiating between these two conditions is an important aspect of accurate diagnosis and therapy. Herein we report two unusual cases of chronic pancreatitis with pseudocyst complicated by obstructive jaundice. 相似文献
995.
Schachinger H Hegar K Hermanns N Straumann M Keller U Fehm-Wolfsdorf G Berger W Cox D 《Journal of behavioral medicine》2005,28(6):587-594
Although both diabetes and the efficacy of medical management are international issues, psycho-educational interventions might
be culturally bound. Blood Glucose Awareness Training (BGAT) is a psycho-educational program for patients with type 1 diabetes
mellitus. It is focused on improving recognition and management of extreme blood glucose levels, and is the best documented
American psycho-educational program for this purpose. A randomized controlled clinical trial of BGAT's long-term benefits
in a non-American setting has been lacking. One hundred and eleven adults with type 1 diabetes mellitus from Switzerland and
Germany participated. After a 6 months baseline assessment, subjects were randomly assigned to receive either 2 months of
BGAT (n = 56) or a physician-guided self-help control intervention (n = 55). BGAT improved recognition of low (p = 0.008), high (p = .03), and overall blood glucose (p = 0.001), and reduced frequency of severe hypoglycemia (p = 0.04), without compromising metabolic control. BGAT reduced both the external locus of control (p < 0.02) and fear of hypoglycemia (p < 0.02). BGAT was efficacious in reducing adverse clinical events and achieving clinically desirable goals in a European,
as well as American setting. 相似文献
996.
We have developed a method for obtaining pneumococcal lipoteichoic acid (LTA) with none, one, or two acyl chains. Anion-exchange chromatography at pH 9.5 yields pneumococcal LTA (labeled LTA-9.5) that has a mass spectrum identical to that of pre-ion-exchange LTA and loses 500 mass units after deacylation by alkali hydrolysis. Anion exchange at pH 10.5 produces LTA (labeled LTA-10.5) with mass peaks that are 264 mass units lower than those of pre-ion-exchange LTA, and deacylation of LTA-10.5 by alkali hydrolysis reduces the mass by only 239 mass units. This result indicates that LTA-10.5 has lost one of the two acyl chains, whereas LTA-9.5 has both acyl chains. When the biological properties of LTA-9.5 and LTA-10.5 are examined with mouse cells, only LTA-9.5 (and not LTA-10.5) is able to stimulate mouse cells to produce tumor necrosis factor alpha, interleukin-1beta, and nitric oxide. In contrast, both LTA-9.5 and LTA-10.5 can stimulate human cells. LTA became inactive when both acyl chains were removed. Thus, acyl chains are critical for LTA function, and small variations in acyl chains can alter biological properties of LTA. 相似文献
997.
BACKGROUND: Young adults with early-onset major depressive disorder (MDD) may be at high risk of progression to bipolar disorder. Although hypomanic symptoms are common in young people with depression, many do not reach the strict DSM-IV and ICD-10 criteria for hypomania. We used an emerging innovative framework for bipolar spectrum to evaluate this question. METHODS: Consecutive referrals to a psychiatric outpatient clinic at a university health service were assessed for recurrent episodes of depression. DSM-IV diagnoses were based on a SCID-1 interview. We used two approaches to delineate bipolar spectrum. The first focused on bipolar spectrum disorder (BSD, as defined by Ghaemi et al. [Can. J. Psychiatry 47 (2002) 125]), and the second on a symptoms perspective based on MDD with a history of hypomanic symptoms, using a 15-point hypomanic symptoms checklist with a cut-off > or =8 or more symptoms (modified from J. Affect. Disord. 73 (2003) 39 and J. Affect. Disord. 73 (2003) 73). Data were also obtained on family history of affective disorder, course and number of episodes of depression, symptom severity, psychosocial functioning, suicidality and deliberate self-harm, and drug and alcohol use. RESULTS: High rates of bipolar and bipolar spectrum disorder were identified. Under DSM-IV, 14 subjects (16.1%) had bipolar affective disorder and 73 subjects (83.9%) had recurrent MDD. Depending on the method used to diagnose bipolar spectrum, between 47.1% and 77.0% of the total cohort could be so diagnosed. Hypomanic symptom counts, irrespective of duration, yielded the highest estimates for bipolar spectrum. High rates of pharmacological hypomania were also identified: 12 subjects (16.4%) with recurrent MDD group reported this, and all could be diagnosed with bipolar spectrum. LIMITATIONS: The reliability of using the 15-point hypomanic scale for the diagnostic assignments was not tested. All subjects were recruited from a university health service and, given the affluence of their parents, findings may not generalise to other populations. Most importantly, because bipolar family history and pharmacological hypomania were part of the diagnostic criteria of the BSD group, they could not be used as external validators for Ghaemi's BSD construct. CONCLUSIONS: Bipolar disorders emerge as extremely common in this cohort of young adults with recurrent depression. Antidepressant-induced hypomania and high scores on a hypomanic symptoms checklist help to identify patients who are likely to have a bipolar spectrum illness, but who do not meet DSM-IV criteria for bipolar disorder. This is a preliminary study, and further evidence from external validating strategies are needed to verify the bipolar status of these patients in a larger and unselected cohort representing a broader socio-economic demographic profile. 相似文献
998.
Transforming growth factor-beta1 increases CXCR4 expression, stromal-derived factor-1alpha-stimulated signalling and human immunodeficiency virus-1 entry in human monocyte-derived macrophages 总被引:3,自引:0,他引:3
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Chen S Tuttle DL Oshier JT Knot HJ Streit WJ Goodenow MM Harrison JK 《Immunology》2005,114(4):565-574
Stromal-derived factor-1 (SDF-1/CXCL12) and its receptor CXCR4 play crucial roles in leukocyte migration and activation, as well as embryogenesis, angiogenesis, cancer and viral pathogenesis. CXCR4 is one of the major human immunodeficiency virus-1 (HIV-1) coreceptors on macrophages. In many tissues macrophages are one of the predominant cell types infected by HIV-1 and act as a reservoir for persistent infection and viral dissemination. In patients infected by HIV-1, blood and tissue levels of transforming growth factor-beta1 (TGF-beta1) are increased. The purpose of this study was to evaluate the effects of TGF-beta1 on CXCR4 expression and function in primary human monocyte-derived macrophages (MDMs) and rat microglia. TGF-beta1 up-regulated CXCR4 and enhanced SDF-1alpha-stimulated ERK1,2 phosphorylation in these cells. The increased CXCR4 expression in human MDMs resulted in increased susceptibility of the cells to entry by dual-tropic CXCR4-using HIV-1 (D-X4). In contrast, TGF-beta1 failed to increase CCR5 expression or infection by a CCR5-using virus in MDMs. Our data demonstrate that TGF-beta1 enhances macrophage responsiveness to SDF-1alpha stimulation and susceptibility to HIV-1 by selectively increasing expression of CXCR4. The results suggest that increased expression of CXCR4 on macrophages may contribute to the emergence of dual-tropic X4 viral variants at later stages of HIV-1 infection. 相似文献
999.
The nonstinging house ant, Monomorium pharaonis (pharaoh ant), was recently identified as a cause of respiratory allergy. This study was performed to evaluate the extent of sensitization to pharaoh ant, and its clinical significance in asthmatic patients. We carried out skin prick tests in 318 patients with asthma. Specific IgE (sIgE) to pharaoh ant was measured by ELISA, and cross-reactivity was evaluated by ELISA inhibition tests. Bronchial provocation testing was performed using pharaoh ant extracts. Fifty-eight (18.2%) of 318 patients showed positive skin responses to pharaoh ant, and 25 (7.9%) had an isolated response to pharaoh ant. Positive skin responses to pharaoh ant were significantly higher among patients with non-atopic asthma than among those with atopic asthma (26.0% vs. 14.9%, p<0.05). There was significant correlation between sIgE level and skin responses to pharaoh ant (rho=0.552, p<0.001). The ELISA inhibition tests indicated that pharaoh ant allergens had various pattern of cross-reactivity to house dust mites and cockroaches. Bronchial provocation tests to pharaoh ant were conducted for 9 patients, and eight showed typical asthmatic reactions. In conclusion, pharaoh ant is an important source of aeroallergens, and it should be included in the skin test battery for screening the causative allergens in patients with asthma. 相似文献
1000.