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Mycobacterium tuberculosis decaprenylphosphoryl-β-d-ribose oxidase (MtbDprE1) acts in concert with decaprenylphosphoryl-β-d-ribose 2-epimerase (MtbDprE2) and catalyzes the epimerization of DPR into DPA. DPA is the sole precursor for synthesis of arabinogalactan and lipoarabinomannan in the mycobacterial cell wall. MtbDprE1 is a unique antimalarial drug target and many covalent and non-covalent inhibitors against MtbDprE1 have been studied for their antituberculosis activities. In the current study, we have purified MtbDprE1 enzyme and synthesized six sulfur-rich 2-mercaptobenzothiazole and 1, 2, 3-triazole conjugated ligands and performed binding analysis with MtbDprE1. All ligands have shown competitive binding, as observed for other covalently and noncovalently bound MtbDprE1 inhibitors. Molecular docking analysis of six ligands with MtbDprE1 shows that they occupy the substrate binding pocket of MtbDprE1 and are stabilized by hydrogen bonds and van der Waals interactions. Our study shows that sulfur-rich 2-mercaptobenzothiazole ligands act as specific inhibitors against MtbDprE1 and could be used as antituberculosis agents.  相似文献   
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Corridor design is a centripetal conservation tool to facilitate movement between fragmented patches. Increases in anthropogenic activity have caused degradation in forest connectivity, influencing animal movement to a small degree. Laljhadi-Mohana wildlife corridor (LMWC), a corridor between Shuklaphanta National Park (Nepal) and Dudhwa National Park (India) created to be used by Panthera tigris and Elephas maximus in western Nepal, is under pressure of anthropogenic change. Using current knowledge, we analyzed land cover changes (LCC) of LMWC between 2002 and 2012. We used ERDAS IMAGINE 9.2 and Arc GIS 9.2 to process satellite images, and occupancy survey to assess status of corridor. We classified land cover into dense forest, sparse forest, cultivation, water bodies, grassland, expose surfaces, and sand bank as structural attributes of the corridor. Our analysis found dense forest area was reduced by 18.35% in a decade while cultivation and sparse forest increased by 10.15% and 8.89%, respectively. Illegal forest encroachment, resource extraction, grazing pressure, invasive species, and flood were major drivers of forest change. The null occupancy model estimated the highest detection probability of Elephas maximus (0.48 ± 0.08) and the lowest of Axis axis (0.20 ± 0.08). Incorporating site covariates improved occupancy estimates of Sus scrofa (0.82), Axis axis (0.76), Elephas maximus (0.76), Boselaphus tragocamelus (0.66), and Panthera pardus (0.55). Distance to cultivation was the most influential covariate, supported by the expansion of cultivated land in the corridor. LMWC is a functional wildlife corridor despite a decline in forest cover. This decline influenced the number and detection rates of large mammals, instigating crop raiding and conflict. Mitigation measures on LCC drivers, particularly forest encroachment, can improve the functional status of LMWC and raise detection rates of large mammals in future studies.  相似文献   
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A family history of atherosclerosis is independently associated with an increased incidence of cardiovascular events. The genetic factors underlying the importance of inheritance in atherosclerosis are starting to be understood. Genetic variation, such as mutations or common polymorphisms has been shown to be involved in modulation of a range of risk factors, such as plasma lipoprotein levels, inflammation and vascular calcification. This review presents examples of present studies of the role of genetic polymorphism in atherosclerosis.  相似文献   
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Maternal oxidative stress during pregnancy may impair fetal growth and help in the development of diseases in adulthood. The aim of current study was to assess total oxidation status (TOS), related parameters and their relationship to DNA damage (%) and homocysteine level in normal pregnant women in low-income participants. In a cross-sectional study healthy women were grouped as normal, while age matched nulliparous and singleton pregnancies were included for first, second and third trimester groups. TOS (P < 0.01), melanodialdehyde (MDA) (P < 0.001), aspartate aminotransferase (AST) (P < 0.01), triiodothyronine (T3) (P < 0.01), thyroxine (T4) (P < 0.01), and homocysteine (P < 0.001), in pregnant women were significantly higher as compared to normal healthy women. While serum total proteins (P < 0.01), albumin (P < 0.01) and total antioxidant status (TAS) (P < 0.001) decreased significantly as compared to normal healthy women. Women in third trimester showed a significantly high level of body temperature (P < 0.01), triglyceride (P < 0.01), LDL-cholesterol (P < 0.05), AST (P < 0.01), T3 (P < 0.01), homocysteine (P < 0.001), TOS (P < 0.01) and MDA (P < 0.001) but a lower concentration of serum proteins, albumin and TAS at the end of the pregnancy. Pearson correlation indicated a positive relationship of homocysteine with triglycerides (P < 0.027), TOS (P < 0.01), MDA (P < 0.035) and had a negative relationship with total protein (P < 0.026). DNA damage was strongly related with T3 (P < 0.008), TOS (P < 0.02), MDA (P < 0.037) and MBI (P < 0.048) profiles of pregnant women. These changes were considered normal for pregnant women having optimum blood pressure and normal child birth. Hormonal influences and hemodilution may contribute towards the observed changes in this study.  相似文献   
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BackgroundPatellar dislocation can lead to instability, pain, limited function, and recurrent dislocations. Medial patellofemoral ligament (MPFL) reconstruction leads to favorable patient reported outcomes, but many patients fail to return to previous activity levels. The purpose of this study is to determine how well patients do after MPFL reconstruction and to determine the most important factors for evaluation of patellar instability following MPFL reconstruction.MethodsAfter IRB approval, a retrospective chart review was performed on all patients who underwent MPFL reconstruction from January 2006 to January 2014 by two board-certified sports orthopaedic surgeons. Patients were then contacted to complete a follow-up questionnaire about satisfaction, functional status, pain, and patellar stability. Patients with at least one-year of follow-up data, a complete data set, and a completed questionnaire were included in the final analysis. Charts of 100 patients were reviewed and 54 patients met all criteria for inclusion in the study. Chi-square analysis, t-tests, and multivariate and univariate logistic regression models were used to estimate the effects of multiple variables on return to activity, satisfaction, and function while controlling for covariates with p<0.05 considered significant.ResultsWhen asked about subluxation, 20% (11/54) reported recurrent patellar subluxation (without re-dislocation). Of the 11 patients who reported re-subluxation, 54% (6/11) reported being highly satisfied (rating of 9-10/10) with the outcome of their knee. Of the 54 patients, 54% (29/54) did not return to previous levels of activity, nevertheless, 31% (9/29) of these 29 patients reported being highly satisfied with the outcome of their knee.ConclusionPatients report high levels of satisfaction even if they have recurrent instability or are unable to return to prior activity levels. Current scoring systems do not accurately depict patients’ post-operative outcomes after MPFL Reconstruction. Level of Evidence: III  相似文献   
39.
CHILL-COMA TOLERANCE, A MAJOR CLIMATIC ADAPTATION AMONG DROSOPHILA SPECIES   总被引:1,自引:1,他引:1  
Abstract.— Most drosophilid species can be classified either as temperate or tropical. Adults of species were submitted to a cold treatment (0°C) and then brought back to ambient temperature. They generally exhibited a chill coma and the time needed to recover was measured. We found in a set of 26 temperate species that recovery was rapid (average 1.8 min, range 0.15–4.9). In contrast, a long recovery time (average 56 min, range 24–120) was observed for 48 tropical species. A few species, like Drosophila melanogaster, are cosmopolitan and can proliferate under temperate and tropical climates. In 9 of 10 such species, slight genetic differences were found: a shorter recovery in temperate than in tropical populations. Comparing physiological data to phylogeny suggests that chill‐coma tolerance has been a recurrent adaptation that is selected for in cold climates but tends to disappear under a permanently warm environment. This major climatic adaptation, evidenced in drosophilids, seems to occur in other insect groups also.  相似文献   
40.
Xylarinase is a bi-functional fibrinolytic metalloprotease isolated from the culture filtrate of endophytic fungus Xylaria curta which is monomeric with a molecular mass of ~33.76?kDa. The enzyme displayed both plasmin and tissue plasminogen activator like activity under in vitro conditions. It hydrolyses Aα and Bβ chains of the fibrinogen. Optimal fibrinolytic activity of xylarinase is observed at 35?°C, pH 8. Ca2+ stimulated the fibrinolytic activity of xylarinase while Fe2+ and Zn2+ inhibited suggesting it to be a metalloprotease. The Km and Vmax values of xylarinase were 240.9?μM and 1.10?U/ml for fibrinogen and 246?μM and 1.22?U/ml for fibrin, respectively. Xylarinase was found to prolong the activated partial thromboplastin time and prothrombin time. The N-terminal sequence of xylarinase (SNGPLPGGVVWAG) did not show any homology with previously known fibrinolytic enzymes. Thus xylarinase is a novel fibrinolytic metalloprotease which could be possibly used as a new clot busting enzyme.  相似文献   
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