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In the present study, methanolic extracts of roots of Vitex negundo L. and extracts of leaves of Vitex negundo L., Ricinus communis L. and Aegle marmelos Corr. were explored for possible antifilarial effect against Brugia malayi microfilariae. It was observed that among the herbal extracts, root extract of Vitex negundo L. and leaves extract of Aegle marmelos Corr. at 100 ng/ml concentration showed complete loss of motility of microfilariae after 48 hr of incubation. Thin layer chromatography of the extracts revealed the presence of alkaloids, saponin and flavonoids in the roots of Vitex negundo L. and coumarin in the leaves of Aegle marmelos Corr.  相似文献   
14.
Abstract The members of the cation diffusion facilitator (CDF) family transport heavy metal ions and play an important function in zinc ion homeostasis of the cell. A recent structure of an Escherichia coli CDF transporter protein YiiP has revealed its dimeric nature and autoregulatory zinc transport mechanism. Here, we report the cloning and heterologous production of four different CDF transporters, two each from the pathogenic mesophilic bacterium Salmonella typhimurium and from the hyperthermophilic bacterium Aquifex aeolicus, in E. coli host cells. STM0758 of S. typhimurium was able to restore resistance to zinc ions when tested by complementation assays in the zinc-sensitive GG48 strain. Furthermore, copurification of bicistronically produced STM0758 and cross-linking experiments with the purified protein have revealed its possible oligomeric nature. The interaction between heavy metal ions and Aq_2073 of A. aeolicus was investigated by titration calorimetry. The entropy-driven, high-affinity binding of two Cd2+ and two Zn2+ per protein monomer with Kd values of around 100 nm and 1 μm, respectively, was observed. In addition, at least one more Zn2+ can be bound per monomer with low affinity. This low-affinity site is likely to possess a functional role contributing to Zn2+ transport across membranes.  相似文献   
15.

Background

The present pilot study investigating the minimum dose for short-course single and double-dose treatment of kala-azar with an apparently new liposomal formulation of amphotericin B, Fungisome, led to identification of immunological components for early detection of success and/or failure to cure.

Methods

Patients were treated with 5, 7.5 (single-dose) and 10 mg/kg body weight (5 mg/kg double-dose) of Fungisome. Immunological investigations involving plasma cytokines and antigen-specific lymphoproliferation and cytokine responses from PBMCs were carried out before, 1 week after Fungisome treatment, at the time of relapse, and again after conventional amphotericin B treatment.

Results

At 1-month follow-up all the patients showed 100% initial cure. However, total doses of 5, 7.5 and 10 mg/kg Fungisome showed 60%, 50% and 90% cure, respectively, at 6-months posttreatment. Patients successfully cured demonstrated downregulation of IL-12 and IL-10 in plasma, and two-fold or more elevation of IFN-γ, IL-12 and TNF, and significant down-regulation of IL-10 and TGF-β in culture supernatants 1-week posttreatment irrespective of drug-dose. A differential immune profile, involving insignificant decline in IL-10 and IL-12 in plasma and negligible elevation of IFN-γ, IL-12 and TNF, and persistence of IL-10, despite decline in TGF-β in culture supernatants, in apparently cured individuals, corresponded with relapse within 6-months of treatment.

Conclusion

Immunological investigations revealed significant curative and non-curative immunomodulation 1-week posttreatment, correlating with successful cure and relapse, respectively. Although immune-correlation was dose-independent, almost consistent curative response in patients treated with the highest dose 10 mg/kg reflected a definitive impact of the higher-dose on the immune response.

Trial registration name and number

Clinical Trials Registry - India (CTRI) CTRI/2009/091/000764  相似文献   
16.
The β-Amylase activity was high in seeds of pre-Milk and milk stages but low in seeds of half seed and dough stages and very low at fully ripe stage of seed development. Zymogen (latent β-Amylase) was absent in half seed stage but appeared at pre-Milk stage. The content of zymogen increased progressively with advance in ripening time. No α-Amylase activity was detected at any stages of seed development in wheat.  相似文献   
17.
Cloning and sequencing of beta toxin gene of Clostridium perfringens type C   总被引:1,自引:0,他引:1  
A gene encoding beta toxin was amplified by polymerase chain reaction from C. perfringens type C isolate and cloned in pUC 19 vector. The nucleotide sequence was identical with C. perfringens type B beta toxin gene sequence. The Southern hybridization using labelled beta toxin gene probe revealed the presence of positive signals only in beta producing C. perfingens.  相似文献   
18.

Background

Type 1 diabetes (T1D) is a multifactorial autoimmune disorder where interaction and integration of immune response genes along with environmental factors play a role in autoimmune destruction of the insulin producing Pancreatic Beta cells.

Methodology/Principal Findings

We have studied four single nucleotide polymorphisms (FokI site in Exon 2, BsmI and ApaI sites in Intron 8 and TaqI site in exon 9) in the vitamin D receptor (VDR) gene using PCR-RFLP and HLA-DRB1 alleles using PCR and hybridization with sequence specific oligonucleotide probes and studied their interaction using LD based statistics for non-linked loci followed by sequence analysis of the vitamin D response element (VDRE) present in the promoter region of HLA-DRB1*0301. Haplotypes, constructed using SHEsis program for four single nucleotide polymorphisms in the VDR gene, were studied for their interaction with HLA-DRB1 alleles in 233 T1D patients and 191 healthy controls from North India. A significant increase of haplotypes FBAt and fBAT (p<0.02, OR = 1.44 and p<0.002, OR = 3.23 respectively) was observed in the patients. Both the haplotypes FBAt and fBAT were significantly increased in male patients with age at onset less than 18 years; however, fBAT was significantly increased in female patients irrespective of their age at onset. LD based statistics showed significant interaction between the high producer F and T alleles with HLA-DRB1*0301. F and T alleles of VDR have been shown to contribute to VDR mRNA independently. The promoter sequence analysis of HLA-DRB1*0301 showed presence of VDRE involved in higher expression of HLA-DRB1*030, which was confirmed by flow cytometry and real time PCR analysis.

Conclusions/Significance

These data suggest that the interaction between VDR and HLA alleles is mediated by VDRE present in the promoter region of HLA-DRB1*0301 allele, which may be detrimental for the manifestation of T1D in the absence of 1,25-(OH)2D3 in early childhood due to poor expression of DRB1*0301 in the thymus resulting in autoimmunity.  相似文献   
19.
A library of seventeen novel 1,2,3-triazole derivatives were efficiently synthesized in excellent yields by the popular ‘click chemistry’ approach and evaluated in vitro for their anti-tubercular activity against Mycobacterium tuberculosis H37Ra (ATCC 25177 strain). Among the series, six compounds exhibited significant activity with minimum inhibitory concentration (MIC) values ranging from 3.12 to 0.78 μg/mL and along with no significant cytotoxicity against MBMDMQs (mouse bone marrow derived macrophages). Molecular docking of the target compounds into the active site of DprE1 (Decaprenylphosphoryl-β-d-ribose-2′-epimerase) enzyme revealed noteworthy information on the plausible binding interactions.  相似文献   
20.
Previous analyses of how mammals vary in their ossification sequences have focused on monotremes, marsupials, and boreoeutherian placentals. Here, we focus on the sequence of cranial and postcranial ossification events during growth in the xenarthran skull and skeleton, including armadillos, anteaters, and sloths. We use two different methods to quantify sequence heterochrony: sequence analysis of variance (ANOVA) and event‐paring/Parsimov. Our results indicate that Parsimov is conservative and does not detect clear heterochronic shifts between xenarthran and boreoeutherian placentals. Sequence‐ANOVA performs better, but both methods exhibit sensitivity to the artifactual accumulation of ties. By controlling for ties and taking into account results that the methods have in common, our analysis suggests that xenarthrans significantly differ from other placentals by a late ossification of the sternum and an early ossification of the phalanges and pubis. We interpret these differences as showing that heterochrony plays a role in the skeletal development of xenarthrans, a change from previous studies that have emphasized the developmental homogeneity of the skeleton across placental mammals.  相似文献   
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