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1.
In order to assess the requirement for the Arg-Gly-Asp-Ser (RGDS) consensus adhesion sequence in von Willebrand factor (vWF) for vWF binding to platelets and endothelial cells, point mutations were introduced into this sequence by site-directed mutagenesis. A glycine to alanine substitution yielded RADS-vWF, while an aspartate to glutamate substitution resulted in RGES-vWF. Recombinant RADS-vWF and RGES-vWF, purified from transformed Chinese hamster ovary cells, were compared with recombinant wild type vWF (WT-vWF) in functional assays with platelets and human umbilical vein endothelial cells (HU-VECs). High molecular weight RADS-vWF and RGES-vWF multimers inhibited binding of 125I-vWF to a mixture of insolubilized native type I and III collagen and competed effectively with 125I-vWF for binding to formalin-fixed platelets in the presence of ristocetin, indicating functional collagen and platelet glycoprotein Ib binding. However, RADS-vWF and RGES-vWF were unable to displace the binding of 125I-vWF to thrombin or ADP-activated platelets. The attachment of HUVECs to either RADS-vWF or RGES-vWF coated surfaces was reduced and spreading was almost completely inhibited, compared with WT-vWF. We conclude that point mutations of the RGDS sequence in vWF selectively impair binding to platelet glycoprotein IIb/IIIa and the HUVEC vitronectin receptor.  相似文献   
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3.

Background

Peripheral artery disease (PAD) is an important global health problem and contributes to notable proportion of morbidity and mortality. This particular manifestation of systemic atherosclerosis is largely under diagnosed and undertreated. For sustainable preventive strategies in a country, it is mandatory to identify country-specific risk factors. We intended to assess the risk factors of PAD among adults aged 40–74 years.

Methods

This case control study was conducted in 2012–2013 in Sri Lanka. Seventy-nine cases and 158 controls in the age group of 40–74 years were selected for the study in order to have case to control ratio 1:2. The criterion for selecting cases and control was based on Ankle brachial pressure index (ABPI). Cases were selected from those who had ABPI 0.85 or less (ABPI ≤0.85) in either lower limb. Controls were selected from those ABPI score between 1.18 and 1.28 in both lower limbs. Only newly identified individuals with PAD were selected as cases. Controls were selected from the same geographical location and within the 5 year age group as cases.

Results

The history of diabetes mellitus more than 10 years (OR 5.8, 95% CI 2.2–14.2), history of dyslipidemia for more than 10 years (OR 4.9, 95% CI 2.1–16.2), history of hypertension for more than 10 years (OR 3.8, 95% CI 1.8–12.7) and smoking (OR 2.9, 95% CI 1.2–6.9), elevated HsCRP (OR 3.7, 95% CI 1.2–12.0) and hyperhomocysteinemia (OR 3.0, 95% CI 1.1–8.1) were revealed as country specific significant risk factor of PAD.

Conclusions

Diabetes mellitus, hypertension, dyslipidemia, smoking as well as elevated homocysteine and HsCRP found as risk factors of PAD. Longer the duration or higher level exposure to these risk factors has increased the risk of PAD. These findings emphasis the need for routine screening of PAD among patients with the identified risk factors.
  相似文献   
4.
Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system.  相似文献   
5.
In order to assess occupational exposure of hospital personnel involved in the preparation and administration of antineoplastic drugs, biological and environmental monitoring are essential to identify the main exposure routes and to quantify potential health risks. If workplace contamination cannot be completely avoided, it is of utmost importance to reduce exposure to the lowest possible levels. To this aim, not only do education and training of the exposed subjects play an important role, but accurate standardized sampling techniques and analytical methods are also required. A critical overview of the most significant methods available in the literature is presented and their value is discussed, especially with respect to their sensitivity and specificity. In addition, attention is given to validation procedures and, consequently, to their reliability. The results from the most important surveys carried out at hospital departments are also discussed, with a view to improving both monitoring strategies and moreover working conditions.  相似文献   
6.
The aim of this study was to investigate the prevalence of pelvic organ prolapse in urban and rural women and to identify possible related factors. They were 1749 participants; one thousand four hundred seventeen (81%) urban women and 332 rural residents (19%). The urban and rural women were congruently regarding to age, parity, using oral contraceptives and postmenopausal status. The urban women were more often obese (p < 0.01), estrogen replacement users (p < 0.001), smokers (p < 0.001), with mild (p < 0.001) and high (p < 0.001) education, and they were often divorced (p < 0.05) than rural women. Rural women were more often alcohol consumers (p < 0.001), with low level of education (p < 0.001) and more often married (p < 0.05) than rural examinees. There were no association between the presence of prolapse and: weight, menopausal status, oral contraceptives and estrogen replacement using, smoking, alcohol consuming and marital status. There were not observed differences in prevalence of prior hysterectomy, urinary incontinence, uroinfectio, sexual and bowel dysfunction between both groups. The prevalence of cystocele, rectocele and uterine prolapse were similar among urban and rural participants. In conclusion, a more complete picture of factors associated with genital prolapse would include in investigation, such as molecular and genetic ones.  相似文献   
7.
2,3-Diarylfuro[2,3-b]pyridine-4-amines are a novel class of potent and selective inhibitors of Lck. The discovery, synthesis, and structure activity relationships of this series of inhibitors are reported. The most promising compounds were also profiled to deduce their pharmacokinetic properties.  相似文献   
8.
De novo satellited non-acrocentric chromosomes are very rare findings in prenatal diagnosis. Here we report the first case of a de novo 18ps, associated with del(18p), detected at prenatal diagnosis. A 37 years old woman underwent Chorionic Villus Sampling (CVS) for advanced maternal age. Cytogenetic analysis on direct CVS preparation (CVSc) revealed a male karyotype with a nonfamilial satellited 18ps and a reciprocal translocation t(17;19)(P11.1;q11) of maternal origin. The mesenchimal CVS culture (CVSm) showed a mosaic of cell lines with various involvement of chromosome 18: 18ps [36/70]/ r(18) [25/70]/ del(18p) [3/70]/ -18 [6/70]. Amniotic fluid cells (AFC) confirmed the homogeneous karyotype found at CVSc. The molecular cytogenetic characterization, performed on AFC, allowed the following diagnosis: 46,XY, +15, dic(15;18)(p11.1;p11.2), t(17;19)(p11.1;q11)mat. ish dic(15;18)(tel 18p-, D15Z1+, wcp18-, wcp 18+, D18Z1+, tel 18q+). The foetal autopsy disclosed subtle facial dysmorphisms and corpus callosum hypoplasia. In case of prenatal detection of de novo terminal ectopic NORs an accurate cytogenetic and molecular analysis should be performed in order to rule out subtle unbalancements.  相似文献   
9.

Background

A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.

Methods

FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.

Results

LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.

Conclusion

Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.
  相似文献   
10.

Background

Persons with Chronic Obstructive Pulmonary Disease (COPD), performing some level of regular physical activity, have a lower risk of both COPD-related hospital admissions and mortality. COPD patients of all stages seem to benefit from exercise training programs, thereby improving with respect to both exercise tolerance and symptoms of dyspnea and fatigue. Physical inactivity, which becomes more severe with increasing age, is a point of concern in healthy older adults. COPD might worsen this scenario, but it is unclear to what degree. This literature review aims to present the extent of the impact of COPD on objectively-measured daily physical activity (DPA). The focus is on the extent of the impact that COPD has on duration, intensity, and counts of DPA, as well as whether the severity of the disease has an additional influence on DPA.

Results

A literature review was performed in the databases PubMed [MEDLINE], Picarta, PEDRO, ISI Web of Knowledge and Google scholar. After screening, 11 studies were identified as being relevant for comparison between COPD patients and healthy controls with respect to duration, intensity, and counts of DPA. Four more studies were found to be relevant to address the subject of the influence the severity of the disease may have on DPA. The average percentage of DPA of COPD patients vs. healthy control subjects for duration was 57%, for intensity 75%, and for activity counts 56%. Correlations of DPA and severity of the disease were low and/or not significant.

Conclusions

From the results of this review, it appears that patients with COPD have a significantly reduced duration, intensity, and counts of DPA when compared to healthy control subjects. The intensity of DPA seems to be less affected by COPD than duration and counts. Judging from the results, it seems that severity of COPD is not strongly correlated with level of DPA. Future research should focus in more detail on the relation between COPD and duration, intensity, and counts of DPA, as well as the effect of disease severity on DPA, so that these relations become more understandable.  相似文献   
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