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71.
A novel Denaturing High-Performance Liquid Chromatography (dHPLC)-based technique allows rapid high-resolution analysis of PCR products. We show the application of this PCR/dHPLC approach for direct detection and identification of bacterium from the Eubacterial PCR amplified products of aqueous and vitreous aspirates from patients with endopthalmitis and to differentially identify the culture negative cases and initiate appropriate therapy. The aim of this study is to identify culture negative PCR positive cases by the application of PCR based DNA sequencing. A total of 116 intraocular specimens were subjected for the study. Sixty-nine different bacteria were identified using dHPLC based DNA sequencing of which predominant ones were Gram-positive bacteria and cannot be cultured by conventional methods. Forty eight different bacteria detected in this study is being reported for the first time in infectious endopthalmitis.  相似文献   
72.
Leptin, the ob gene product, is a 167 amino acid polypeptide known to play a key role in regulating the fat stores of the body and is found in all eukaryotes, including mammals, aves, and also in invertebrates. To gain insight into the structure-function relation and origin of leptin, we have analyzed the amino acid sequence of leptin from 23 species by computing the frequency of occurrence of amino acids, their secondary structure, sequence homology, et cetera. Extensive conservation is observed within the leptin sequences of all the species, suggesting an evolutionary relatedness among them. It is interesting to note that human leptin shares a very high degree of homology with gorilla, chimpanzee, and orangutan indicative of a common function of leptin in them. Analysis of the codon bias in leptin from 11 species reveals that sminthopsis shows highest variation compared to human while less variation is observed in chimpanzee and orangutan, possibly reflecting the closeness in their evolution. Thus, understanding leptin's three-dimensional structure along with primary and secondary structure might enable us to understand the functional role played by this multifaceted adipocyte derived protein.  相似文献   
73.
Overnourishment during the suckling period [small litter (SL)] results in the development of adult-onset obesity. To investigate the mechanisms that underlie the development of insulin resistance in the skeletal muscle of young and adult female SL rats, the litter size was reduced to 3 female pups/dam (SL) while the control litter had 12 pups/dam from the postnatal Day 3 until Day 21. Protein content, mRNA expression and methylation status of the promoter region of key components in the insulin signaling pathway were determined in the skeletal muscle of SL rats. Overnutrition during the suckling period resulted in increased body weight gains, hyperphagia and adult-onset obesity as well as increased levels of serum insulin, glucose and leptin in SL rats. No differences in the expression of total protein as well as tyrosine phosphorylation of insulin receptor β and glucose transporter 4 (Glut4) were observed in skeletal muscle between two groups at both ages. A significant decrease of total insulin receptor substrate 1 (IRS-1) and an increase in serine phosphorylation of IRS-1 were observed in skeletal muscle from adult SL rats. Hypermethylation of specific cytidyl-3',5'phospho-guanylyl (CpG) dinucleotides in the proximal promoter region was observed for the Irs1 and Glut4 genes, which correlated with the reduction in Irs1 and Glut4 mRNA levels in skeletal muscle of adult SL rats. Our results suggest that epigenetic modifications of the key genes involved in the insulin signaling pathway in skeletal muscle could result in the development of insulin resistance in SL female rats.  相似文献   
74.
Calcium (Ca2+) release from the endoplasmic reticulum (ER) controls numerous cellular functions including proliferation, and is regulated in part by inositol 1,4,5-trisphosphate receptors (IP3Rs). IP3Rs are ubiquitously expressed intracellular Ca2+-release channels found in many cell types. Although IP3R-mediated Ca2+ release has been implicated in cellular proliferation, the biochemical pathways that modulate intracellular Ca2+ release during cell cycle progression are not known. Sequence analysis of IP3R1 reveals the presence of two putative phosphorylation sites for cyclin-dependent kinases (cdks). In the present study, we show that cdc2/CyB, a critical regulator of eukaryotic cell cycle progression, phosphorylates IP3R1 in vitro and in vivo at both Ser(421) and Thr(799) and that this phosphorylation increases IP3 binding. Taken together, these results indicate that IP3R1 may be a specific target for cdc2/CyB during cell cycle progression.  相似文献   
75.
Non-pathogenic soil bacteria living in association with roots of higher plants enhance their adaptive potential and thus could be beneficial for their growth. Here, we present the current status of the use of Bacillus subtilis in biocontrol. Rhizobacteria are found in the rhizosphere. Plant growth promoting rhizobacteria (PGPR) strains, such as Bacillus and Pseudomonas, were isolated by using Nutreint dextrose Agar medium or Potato Dextrose Agar medium. The selection of PGPR strains was done by duel culture methods against the potato pathogens. The interaction of PGPR (Bacillus) with potato seeds or vegetative parts show promising antagonism by virtue of producing siderophore and antibiotics against black scurf and stem canker diseases of potato caused by Rhizoctonia solani, thereby resulting in increase of potato yield. The effectiveness of PGPR strain (Bacillus spp.) in improving the yield of potato in greenhouse conditions and in the field was observed.  相似文献   
76.
TNBC is an aggressive breast cancer subtype that does not express hormone receptors (estrogen and progesterone receptors, ER and PR) or amplified human epidermal growth factor receptor type 2 (HER2), and there currently exist no targeted therapies effective against it. Consequently, finding new molecular targets in triple negative breast cancer (TNBC) is critical to improving patient outcomes. Previously, we have detected the expression of metabotropic glutamate receptor-1 (gene: GRM1; protein: mGluR1) in TNBC and observed that targeting glutamatergic signaling inhibits TNBC growth both in vitro and in vivo. In this study, we explored how mGluR1 contributes to TNBC progression, using the isogenic MCF10 progression series, which models breast carcinogenesis from nontransformed epithelium to malignant basal-like breast cancer. We observed that mGluR1 is expressed in human breast cancer and that in MCF10A cells, which model nontransformed mammary epithelium, but not in MCF10AT1 cells, which model atypical ductal hyperplasia, mGluR1 overexpression results in increased proliferation, anchorage-independent growth, and invasiveness. In contrast, mGluR1 knockdown results in a decrease in these activities in malignant MCF10CA1d cells. Similarly, pharmacologic inhibition of glutamatergic signaling in MCF10CA1d cells results in a decrease in proliferation and anchorage-independent growth. Finally, transduction of MCF10AT1 cells, which express c-Ha-ras, using a lentiviral construct expressing GRM1 results in transformation to carcinoma in 90% of resultant xenografts. We conclude that mGluR1 cooperates with other factors in hyperplastic mammary epithelium to contribute to TNBC progression and therefore propose that glutamatergic signaling represents a promising new molecular target for TNBC therapy.  相似文献   
77.
p21-activated kinase 1 (Pak1)—a key node protein kinase regulating various cellular process including angiogenesis—has been recognised to be a therapeutic target for multitude of diseases, and hence, various small molecule inhibitors targeting its activity have been tested. However, the direct toxic and anti-angiogenic effects of these pharmacologic agents have not been examined. In this study, we evaluate the translational efficacy of Pak1 inhibitor IPA-3 using zebrafish toxicity model system to stratify its anti-angiogenic potential and off-target effects to streamline the compound for further therapeutic usage. The morphometric analysis has shown explicit delay in hatching, tail bending, pericardial sac oedema and abnormal angiogenesis. We provide novel evidence that Pak1 inhibitor could act as anti-angiogenic agents by impeding the development of sub-intestinal vessel (SIV) and intersegmental vessels (ISVs) by suppressing the expression of vascular endothelial growth factor (VEGF), VEGF receptor 2 (VEGFR2), neurophilin 1 (NRP1) and its downstream genes matrix metalloproteinase (MMP)-2 and MMP-9. Knockdown studies using 2-O-methylated oligoribonucleotides targeting Pak1 also revealed similar phenotypes with inhibition of angiogenesis accompanied with deregulation of major angiogenic factor and cardiac-specific genes. Taken together, our findings indicate that Pak1 signalling facilitates enhanced angiogenesis and also advocated the design and use of small molecule inhibitors of Pak1 as potent anti-angiogenic agents and suggest their utility in combinatorial therapeutic approaches targeting anomalous angiogenesis.  相似文献   
78.
BackgroundGlucose-6-phosphate dehydrogenase (G6PD) deficiency is a common enzyme deficiency, prevalent in many malaria-endemic countries. G6PD-deficient individuals are susceptible to hemolysis during oxidative stress, which can occur from exposure to certain medications, including 8-aminoquinolines used to treat Plasmodium vivax malaria. Accordingly, access to point-of-care (POC) G6PD testing in Brazil is critical for safe treatment of P. vivax malaria.Methodology/Principal findingsThis study evaluated the performance of the semi-quantitative, POC STANDARD G6PD Test (SD Biosensor, Republic of Korea). Participants were recruited at clinics and through an enriched sample in Manaus and Porto Velho, Brazil. G6PD and hemoglobin measurements were obtained from capillary samples at the POC using the STANDARD and HemoCue 201+ (HemoCue AB, Sweden) tests. A thick blood slide was prepared for malaria microscopy. At the laboratories, the STANDARD and HemoCue tests were repeated on venous samples and a quantitative spectrophotometric G6PD reference assay was performed (Pointe Scientific, Canton, MI). G6PD was also assessed by fluorescent spot test. In Manaus, a complete blood count was performed.Samples were analyzed from 1,736 participants. In comparison to spectrophotometry, the STANDARD G6PD Test performed equivalently in determining G6PD status in venous and capillary specimens under varied operating temperatures. Using the manufacturer-recommended reference value thresholds, the test’s sensitivity at the <30% threshold on both specimen types was 100% (95% confidence interval [CI] venous 93.6%–100.0%; capillary 93.8%–100.0%). Specificity was 98.6% on venous specimens (95% CI 97.9%–99.1%) and 97.8% on capillary (95% CI 97.0%–98.5%). At the 70% threshold, the test’s sensitivity was 96.9% on venous specimens (95% CI 83.8%–99.9%) and 94.3% on capillary (95% CI 80.8%–99.3%). Specificity was 96.5% (95% CI 95.0%–97.6%) and 92.3% (95% CI 90.3%–94.0%) on venous and capillary specimens, respectively.Conclusion/SignificanceThe STANDARD G6PD Test is a promising tool to aid in POC detection of G6PD deficiency in Brazil.Trial registrationThis study was registered with ClinicalTrials.gov (identifier: NCT04033640).  相似文献   
79.
80.
Around 39 well characterised viruses affect cucurbits crops in developing countries and their viral diversity may be the consequence for genetic and ecological diversity of their hosts. Indeed, cucurbits are grown in variety of climatic, environmental and agricultural conditions, and this may provide more or less favourable conditions for the specific viruses or their hosts. The presence of various viral diseases caused by different viruses in Maharashtra was studied from the infected samples collected from cucurbits and melons during the survey conducted in 2009–2010 in different locations. The virus isolates collected from various cucurbitaceous crops were established and their host ranges were studied by sap transmission. The study revealed Cucumber Mosaic Virus (CMV), Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV) and Cucumber green mottle mosaic virus infections predominately found in Nashik region, and Watermelon bud necrosis virus (WBNV), CMV, ZYMV, WMV and Watermelon silver mottle virus (WSMoV) infections in Aurangabad and Paithan regions. In Sangamner region, the crop was mostly affected by WBNV, ZYMV and WSMoV, and CMV was found only in Sillod region. The protocols for performing sap transmission tests in assay hosts were standardised for ZYMV, CMV and WBNV. Using direct antigen-coating enzyme-linked immunosorbent assay, of all the plant parts, young leaves were found to have high concentration of virus and suitable for virus detection in screening programmes. CMV and ZYMV was found to have high concentration of virus and suitable for virus detection in screening programmes.  相似文献   
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