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81.
[Ru(bzimpy)(2)]Cl(2), where bzimpy is 2,6-bis(benzimidazol-2-yl) pyridine was synthesized and characterized by ESI-MS, UV-Visible, (1)H NMR and fluorescence spectra. Absorption titration and thermal denaturation experiments indicate that the complex binds to DNA with moderate strength. Viscosity measurement shows that the mode of binding could be surface binding. Fluorescence study shows that the fluorescence intensity of the complex decreases with increasing concentrations of DNA, which is due to the photoelectron transfer from guanine base to (3)MLCT of the complex. Photoexcitation of the complex in the MLCT region in the presence of plasmid DNA has been found to give rise to nicking of DNA.  相似文献   
82.
Summary Ninety local cultivars and 124 induced grain shape mutants were screened for their protein content and the distribution of protein in their endosperm. The protein content varied widely from 4.2 to 12.1% in the local varieties and from 5.5 to 13.7% in the mutants. Some high protein lines like Chinnavadlu, Budumavadlu, etc. with more than 10.0% protein were identified. Protein distribution studies have shown that several mutants, such as IR-8-FG-28, IR-8-FG-33, etc., have a deeper distribution of protein bodies and some local cultivars, like Kakathya and Muchulu, have a relatively more uniform distribution of protein in the endosperm. The protein content at different milling levels revealed that at 12% milling the percentage retention of protein varied from about 79 to 96% irrespective of the percentage of protein, suggesting that the distribution of protein, in addition to the protein content, plays an important role in nutritive value of rice.  相似文献   
83.
BackgroundThe global epidemic of type 2 diabetes mellitus (T2DM) renders its prevention a major public health priority. A key risk factor of diabetes is obesity and poor diets. Food environments have been found to influence people’s diets and obesity, positing they may play a role in the prevalence of diabetes. Yet, there is scant evidence on the role they may play in the context of low- and middle-income countries (LMICs). We examined the associations of food environments on T2DM among adults and its heterogeneity by income and sex.Methods and findingsWe linked individual health outcome data of 12,167 individuals from a network of health surveillance sites (the South Asia Biobank) to the density and proximity of food outlets geolocated around their homes from environment mapping survey data collected between 2018 and 2020 in Bangladesh and Sri Lanka. Density was defined as share of food outlets within 300 m from study participant’s home, and proximity was defined as having at least 1 outlet within 100 m from home. The outcome variables include fasting blood glucose level, high blood glucose, and self-reported diagnosed diabetes. Control variables included demographics, socioeconomic status (SES), health status, healthcare utilization, and physical activities. Data were analyzed in ArcMap 10.3 and STATA 15.1. A higher share of fast-food restaurants (FFR) was associated with a 9.21 mg/dl blood glucose increase (95% CI: 0.17, 18.24; p < 0.05). Having at least 1 FFR in the proximity was associated with 2.14 mg/dl blood glucose increase (CI: 0.55, 3.72; p < 0.01). A 1% increase in the share of FFR near an individual’s home was associated with 8% increase in the probability of being clinically diagnosed as a diabetic (average marginal effects (AMEs): 0.08; CI: 0.02, 0.14; p < 0.05). Having at least 1 FFR near home was associated with 16% (odds ratio [OR]: 1.16; CI: 1.01, 1.33; p < 0.05) and 19% (OR: 1.19; CI: 1.03, 1.38; p < 0.05) increases in the odds of higher blood glucose levels and diagnosed diabetes, respectively. The positive association between FFR density and blood glucose level was stronger among women than men, but the association between FFR proximity and blood glucose level was stronger among men as well as among those with higher incomes. One of the study’s key limitations is that we measured exposure to food environments around residency geolocation; however, participants may source their meals elsewhere.ConclusionsOur results suggest that the exposure to fast-food outlets may have a detrimental impact on the risk of T2DM, especially among females and higher-income earners. Policies should target changes in the food environments to promote better diets and prevent T2DM.

Dian Kusuma and colleagues investigate the associations between exposure to the density and proximity of healthy and unhealthy food outlets and diabetes in Bangladesh and Sri Lanka.  相似文献   
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85.
Vesicular stomatitis virus (VSV) is an essentially nonpathogenic negative-stranded RNA virus, the replication of which is extremely sensitive to the antiviral effects of interferon (IFN). We demonstrate here that VSV selectively induces the cytolysis of numerous transformed human cell lines in vitro, with all the morphological characteristics of apoptotic cell death. Importantly, VSV can also potently inhibit the growth of p53-null C6 glioblastoma tumors in vivo without infecting and replicating in normal tissue. With our previous findings demonstrating that primary cells containing the double-stranded RNA-activated protein kinase PKR and a functional IFN system are not permissive to VSV replication, these results suggest that signaling by IFN may be defective in many malignancies. Thus VSV might be useful in novel therapeutic strategies for targeting neoplastic disease.  相似文献   
86.
Aspartic proteases of human malarial parasites are thought to play key roles in essential pathways of merozoite release, invasion and host cell hemoglobin degradation during the intraerythrocytic stages of their life cycle. Therefore, we have purified and characterized Plasmodium vivax aspartic protease, to determine if this enzyme can be used as potential drug target/immunogen, and its inhibitors as potential antimalarial drug. The P. vivax aspartic protease has been purified by a combination of ion exchange and size exclusion chromatographies and HPLC. Its properties were examined in order to define a role in the hemoglobin degradation process. The purified enzyme migrated as a single band on native PAGE and SDS/PAGE with a molecular mass of 40 kDa. Gelatin zymogram analyses revealed a clear zone of proteolytic activity corresponding to the band obtained on native PAGE and SDS/PAGE. The enzyme has an optimal pH of 4.0 and exhibits its highest activity at 37 degrees C. The enzyme is inhibited by pepstatin, but not by other inhibitors including o-phenanthroline, EDTA, PMSF or E-64, supporting its designation as an aspartic protease; its IC50 value was found to be 3.0 microM. A Lineweaver Burk double reciprocal plot with pepstatin shows that the inhibition is competitive with respect to the substrate. Ca2+ and Mg2+ ions enhance the protease activity, whereas Cu2+ and Hg2+ ions were found to be inhibitory. The pivotal role of aspartic protease in initiating hemoglobin degradation in P. vivax malaria parasite is also demonstrated.  相似文献   
87.
88.
Benign intracranial hypertension (BIH) or idiopathic intracranial hypertension (IIH) is a rare disorder of unknown etiology that is most often seen in obese women of reproductive age (19.3/100,000) and is reported only occasionally during pregnancy. Both pregnancy and exogenous estrogens are thought to promote IIH or worsen it. It can occur in any trimester during pregnancy, and the visual outcome is the same as for nonpregnant patients with IIH. There is no increase in fetal wastage; therapeutic abortion to limit its progression is not indicated, and subsequent pregnancies do not increase the risk of recurrence. Most therapies used during the nonpregnant state can also be used during pregnancy. The aim of treatment is to preserve vision and improve symptoms. Treatments include analgesics, diuretics, steroids, and serial lumbar punctures. When medical therapy fails, surgical procedures need to be considered. Although this condition has been reviewed often, the issue of mode of delivery, especially when papilledema has not resolved, is unclear. We report on 3 women with IIH during pregnancy and review the choice of therapy and mode of delivery.  相似文献   
89.
Cervical cancer is rated the second most common malignant tumour globally, and is aetiologically linked to human papillomavirus (HPV) infection. Here the cellular pathology under consideration of stem/progenitor cell carcinogenesis is reviewed. Of the three causative molecular mechanisms of cervical cancer, two are associated with HPV: firstly, the effect of the viral oncogenes, E6 and E7; and secondly, integration of the viral DNA into chromosomal regions of tumour phenotype. The third process involved is the repetitive loss of heterozygosity in some chromosomal regions. HPV can be classified into high- and low-risk types; the high-risk types encode two oncoproteins, E6 and E7, which interact with tumour suppressor proteins. The association results in the inactivation of tumour suppressor proteins and the abrogation of apoptosis. Apoptosis is referred to as programmed cell death, whereby a cell deliberately commits suicide, and thus regulates cell numbers during development and maintenance of cellular homeostasis. This review attempts to elucidate the role of apoptotic genes, and considers external factors that interact with HPV in the development and progression of cervical cancer. Therefore, an in-depth understanding of the apoptotic genes that control molecular mechanisms in cervical cancer are of critical importance. Useful targets for therapeutic strategies would be those that alter apoptotic pathways in a manner where the escape of HPV from surveillance by the host immune system is prevented. Such an approach directed at the apoptotic genes maybe useful in the treatment of cervical cancer.  相似文献   
90.
BACKGROUND: The recombinant antigen BmR1 has been extensively employed in both ELISA and immunochromatographic rapid dipstick (Brugia Rapid) formats for the specific and sensitive detection of IgG4 antibodies against the lymphatic filarial parasites Brugia malayi and Brugia timori. In sera of individuals infected with Wuchereria bancrofti the IgG4 reactivity to BmR1 is variable, and cross-reactivity of sera from individuals infected with Onchocerca volvulus or Loa loa was observed only in single cases. In order to characterize the homologs of the BmR1 antigen in W. bancrofti (Wb-BmR1), O. volvulus (Ov-BmR1) and L. loa (Ll-BmR1) the cDNA sequences were identified, the protein expressed and the antibody reactivity of patients' sera was studied. METHODS: PCR methodology was used to identify the cDNA sequences from cDNA libraries and/or genomic DNA of W. bancrofti, O. volvulus and L. loa. The clones obtained were sequenced and compared to the cDNA sequence of BmR1. Ov-BmR1 and Ll-BmR1 were expressed in E. coli and tested using an IgG4-ELISA with 262 serum samples from individuals with or without B. malayi, W. bancrofti, O. volvulus and L. loa infections or various other parasitic infections. BmR1, Ov-BmR1 and Ll-BmR1 were also tested for reactivity with the other three IgG subclasses in patients' sera. RESULTS: Wb-BmR1 was found to be identical to BmR1. Ov-BmR1 and Ll-BmR1 were found to be identical to each other and share 99.7% homology with BmR1. The pattern of IgG4 recognition of all serum samples to BmR1, Ov-BmR1 and Ll-BmR1 were identical. This included weak IgG4 reactivities demonstrated by L. loa- and O. volvulus-infected patients tested with Ov-BmR1 and Ll-BmR1 (or BmR1). With respect to reactivity to other IgG subclasses, sera from O. volvulus- and L. loa-infected patients showed positive reactions (when tested with BmR1, Ov-BmR1 or Ll-BmR1 antigens) only with IgG1. No reactivity was observed with IgG2 or with IgG3. Similarly, ELISAs to detect reactivity to other anti-filarial IgG subclasses antibodies showed that sera from individuals infected with B. malayi or W. bancrofti (active infections as well as patients with chronic disease) were positive with BmR1 only for IgG1 and were negative when tested with IgG2 and with IgG3 subclasses. CONCLUSIONS: This study demonstrates that homologs of the BmR1 antigen are present in W. bancrofti, O. volvulus and L. loa and that these antigens are highly conserved. Recognition of this antigen by patients' sera is similar with regard to IgG1, IgG2 and IgG3, but different for IgG4 antibodies. We conclude that the BmR1 antigen is suitable for detection of IgG4 antibodies in brugian filariasis. However, its homologs are not suitable for IgG4-based diagnosis of other filarial infections.  相似文献   
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