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排序方式: 共有518条查询结果,搜索用时 31 毫秒
1.
2.
Hydrosalpinges adversely affect markers of endometrial receptivity 总被引:22,自引:10,他引:22
Meyer WR; Castelbaum AJ; Somkuti S; Sagoskin AW; Doyle M; Harris JE; Lessey BA 《Human reproduction (Oxford, England)》1997,12(7):1393-1398
While in-vitro fertilization (IVF) was initially developed in women with
tubal factor infertility, recent clinical studies have suggested that the
presence of hydrosalpinges lowers implantation and pregnancy rates. We
postulated that these hydrosalpinges cause impaired endometrial
receptivity. A total of 103 women with hydrosalpinges were prospectively
evaluated, and compared with 55 infertile and 44 fertile controls. All
women had endometrial biopsies during the window of implantation, analysed
by conventional histological criteria, and also stained for three integrin
markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha
vbeta3). Women with hydrosalpinges (cases) expressed significantly less of
the alpha vbeta3 integrin compared with controls. There was no difference
in expression of alpha1beta1 or alpha4beta1 among groups. A significantly
greater number of cases had out of phase histology and missing alpha vbeta3
(type I defects) and absent integrin expression despite normal histological
maturation (type II) defects, compared with controls. Of 20 women with
impaired endometrial receptivity who were also biopsied after hydrosalpinx
surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven
percent of type I and 57% of type II defects were corrected
postoperatively. Using markers of endometrial receptivity, this study
demonstrates that inflammatory hydrosalpinges have an adverse effect on
endometrial receptivity, which in some cases may be overcome by surgical
treatment of the hydrosalpinx.
相似文献
3.
Intratracheal administration of liposomal clodronate accelerates alveolar macrophage reconstitution following fetal liver transplantation 总被引:1,自引:0,他引:1
Everhart MB Han W Parman KS Polosukhin VV Zeng H Sadikot RT Li B Yull FE Christman JW Blackwell TS 《Journal of leukocyte biology》2005,77(2):173-180
To facilitate study of alveolar macrophages in vivo, we developed a method to rapidly and efficiently replace resident alveolar macrophages with macrophages of a different (donor) genotype. Chimeric mice were generated by lethal irradiation followed by fetal liver transplantation (FLT) using green fluorescent protein (GFP) transgenic reporter mice as donors. Kinetics of peripheral blood monocyte (PBM) and alveolar macrophage reconstitution was determined 4 and 10 weeks post-FLT by quantifying the percentage of GFP+ cells. To enhance the recruitment of donor monocytes into the lung after FLT, mice were treated with intratracheal administration of liposomal clodronate to deplete host alveolar macrophages at 6 weeks post-FLT. PBM reconstitution occurred by 4 weeks after FLT (85.7+/-1.6% of CD11b+/Gr-1+ monocytes were GFP+), and minimal alveolar macrophage repopulation was observed (9.5% GFP+). By 10 weeks following FLT, 48% of alveolar macrophages were GFP+ by immunostaining of macrophages on lung tissue sections, and 55.1 +/- 1.6% of lung lavage macrophages were GFP+ by fluorescein-activated cell sorter analysis. Clodronate treatment resulted in a significant increase in GFP+ alveolar macrophages 10 weeks after FLT. By immunostaining, 90% of macrophages were GFP+ on lung tissue sections and 87.5 +/- 1.1% GFP+ in lung lavage (compared with GFP-transgenic controls). The ability of newly recruited alveolar macrophages to clear Pseudomonas aeruginosa and activate nuclear factor-kappaB in response to Eschericia coli lipopolysaccharide demonstrated normal macrophage function. Optimizing this methodology provides an important tool for the study of specific genes and their contribution to alveolar macrophage function in vivo. 相似文献
4.
bcl-2 transgene expression promotes survival and reduces proliferation of CD3-CD4-CD8- T cell progenitors 总被引:16,自引:0,他引:16
Proliferative expansion and apoptotic cell death play prominent roles in T
cell development. The molecular control of cell cycle progression and
apoptosis appear to be inter-connected since the Bcl-2 protein can inhibit
apoptosis and slow cell cycle progression in cortical thymocytes and mature
T cells, particularly during the transition from the quiescent state into
the cell cycle. Here the impact of bcl-2 transgene expression on
CD3-CD4-CD8- T cell progenitors was assessed. Bcl-2 enhanced the survival
of these progenitors at all of the four major differentiation stages, CD25-
CD44+ (pro-T1), CD25 + CD44+ (pro- T2), CD25 + CD44- (pro-T3) and
CD25-CD44- (pro-T4). However, it reduced cell cycling and slowed turnover
only in the pro-T4 subset. From an analysis of bcl-2 transgenic mice
expressing a TCR transgene or bearing a mutation in the scid or rag-1 gene
we conclude that Bcl-2 inhibits proliferation only of T cell progenitors
that are activated via the pre- TCR, not those stimulated via c-Kit and the
IL-7 receptor.
相似文献
5.
James E. Everhart Deanna Kruszon-Moran Guillermo Perez-Perez 《Clinical and Vaccine Immunology : CVI》2002,9(2):412-416
Background serological assays for Helicobacter pylori are commonly used without knowledge of reliability. This information is needed to define the ability of serological tests to determine either new cases of infection or loss of infection in longitudinal studies. We evaluated the reproducibility and the interrelationships of serological test results for H. pylori and cytotoxin-associated gene product A (CagA) enzyme-linked immunoassays within a subset of participants in a population-based study. Stored samples from 1,229 participants in the third U.S. National Health and Nutrition Examination Survey were replicate serologically tested for H. pylori and CagA. Overall disagreement was 3.4% between duplicate tests for H. pylori (or 2.3% if equivocal results were disregarded). Six percent of samples positive on the first test had an immune serum ratio at least 30% lower on repeat testing. The odds ratio for H. pylori seropositivity on retesting was 2.8 (95% confidence interval [CI] = 1.8 to 4.5) when CagA serology was positive versus when it was negative. CagA antibody was found among 47.8% of H. pylori-equivocal and 7.0% of H. pylori-negative samples. CagA-positive yet H. pylori-negative samples were more likely to occur among Mexican Americans (odds ratio, 5.2; 95% CI = 2.4 to 11.4) and non-Hispanic blacks (odds ratio, 5.5; 95% CI = 2.3 to 13.0) than among non-Hispanic whites. Relying on repeated H. pylori serological tests over time to determine infection rates may result in misinterpretation due to limits in test reproducibility. CagA testing may have a role in verifying infection. 相似文献
6.
Mutations in the Ca(2+)-sensing receptor gene cause autosomal dominant and sporadic hypoparathyroidism 总被引:3,自引:0,他引:3
Baron J; Winer KK; Yanovski JA; Cunningham AW; Laue L; Zimmerman D; Cutler GB Jr 《Human molecular genetics》1996,5(5):601-606
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane
domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that
activating mutations in this receptor might cause autosomal dominant
hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified,
in two families with ADHP, heterozygous missense mutations in the
Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of
50 normal controls had either mutation. We also identified a de novo,
missense Ca(2+)-sensing receptor mutation in a child with severe sporadic
hypoparathyroidism. The amino acid substitution in one ADHP family affected
the N-terminal, extracellular domain of the receptor. The other mutations
involved the transmembrane region. Unlike patients with acquired
hypoparathyroidism, patients with these mutations had hypercalciuria even
at low serum calcium concentrations. Their greater hypercalciuria
presumably reflected activation of Ca(2+)-sensing receptors in kidney
cells, where the receptor negatively regulates calcium reabsorption. This
augmented hypercalciuria increases the risk of renal complications and thus
has implications for the choice of therapy.
相似文献
7.
Symptomatic peripheral arterial disease: the value of a validated questionnaire and a clinical decision rule
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Bianca LW Bendermacher Joep AW Teijink Edith M Willigendael Marie-Louise Bartelink Harry R Büller Ron JG Peters Jelis Boiten Machteld Langenberg Martin H Prins 《The British journal of general practice》2006,56(533):932-937
BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease. 相似文献
8.
R P Nath R A Upton E T Everhart P Cheung P Shwonek R T Jones J E Mendelson 《Journal of clinical pharmacology》1999,39(6):619-623
Buprenorphine is an effective new treatment for opiate dependence. This study compared the bioavailability of buprenorphine from a tablet to that from a reference solution. Six men experienced with, but not dependent on, opiates (DSM-III-R) were each administered 7.7 mg of buprenorphine in liquid form and 8 mg in tablet form 1 week apart in a balanced crossover design. Plasma levels were measured by electron capture capillary gas chromatography (GC), and concentration-time curves were constructed. Pharmacokinetic data were analyzed by analysis of variance. The bioavailability from the tablet was approximately 50% that from the liquid and was not affected by saliva pH. Lower bioavailability from the tablet may be due to slow dissolution. 相似文献
9.
Panganiban K Jacob P Everhart ET Tisdale EC Batki SL Mendelson JE Jones RT 《Journal of analytical toxicology》1999,23(7):581-585
Recent studies have demonstrated the utility of quantitative assays for benzoylecgonine in assessing the efficacy of cocaine-dependence-treatment programs to determine if the amount of cocaine consumed has been reduced. We describe a simple gas chromatographic method for determining benzoylecgonine concentrations in urine. BZE is extracted from urine as an ion pair with tri-n-propylsulfonium ion. Injection into the heated injection port of the gas chromatograph results in thermal conversion of the ion pair to the n-propyl ester of BZE. Using the structural analogue of BZE, m-toluylecgonine, as the internal standard, the analysis is carried out on a (5% phenyl)methylpolysiloxane capillary column with nitrogen-phosphorus detection. There was a good correlation between BZE concentrations determined by gas chromatography-mass spectrometry and concentrations determined by the method described in this paper. Application to cocaine-dependence-treatment programs is discussed. 相似文献
10.
Sichieri R Everhart JE Mendonça GA 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1996,12(1):53-59
A prospective ecological evaluation of mortality from common malignancies with dietary risk factors and alcohol consumption was carried out among 10 state capitals of Brazil. Regression analysis was used to examine the association of dietary intake with mortality rates of the most common cancers among adults age 30 years and older. Age-adjusted cancer mortality rates varied 2.4 to 3.3 fold across the state capitals. A positive relationship was observed between energy intake and colon, lung, and esophageal cancer (p=0.02 for each). Colon cancer mortality was positively associated with consumption of total fat, eggs, alcohol, mate tea, cereals, and vegetables (p=0.01). Lung cancer was positively associated with mate and cereal intake (p<0.05). Stomach cancer was associated with consumption of eggs (p=0.04); and negatively associated with consumption of high fiber foods, fruits, and vitamin A and C (p=0.05). Esophageal cancer was positively associated with fat intake, mate and cereals (p=0.05) and negatively associated with vitamin A (p=0.02); prostate cancer was negatively associated with vitamin C (p=0.007). Breast cancer was not associated with any of the factors studied. The marked variation in cancer mortality rates in Brazil may be partially related to the high variation in dietary components or other diet associated factors. 相似文献