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951.

Purpose

To evaluate the effects of prostatic anatomical factors on male lower urinary tract symptoms (LUTS) and the peak flow rate (Qmax) in patients with small prostate volume (PV).

Materials and Methods

Records were obtained from a prospectively maintained database of first-visit men with LUTS. Patients whose total PV (TPV) was greater than 30 mL were excluded; 444 patients were enrolled in the study. The TPV, transitional zone volume (TZV), transitional zone index (TZI), intravesical prostatic protrusion (IPP), and prostatic urethral angle (PUA) were measured by transrectal ultrasonography. LUTS were evaluated using the International Prostate Symptom Score (IPSS) and the Overactive Bladder Symptom Score (OABSS) questionnaires. Uroflowmetric measurements were also made.

Results

PUA (r = 0.269, P<0.001), TZV (r = 0.160, P<0.001), and TZI (r = 0.109, P = 0.022) significantly correlated with the IPSS. Qmax (r = −0.334, P<0.001) and OABSS (r = 0.211, P<0.001) correlated only with PUA. In a multivariate regression analysis, PUA and age were independently associated with IPSS, OABSS, and Qmax. For IPSS of 20 or greater, the area under the ROC curve (AUC) of PUA was 0.667 and the cut-off value was 43.7°. When Qmax was 10 mL/s or less, the AUC of PUA was 0.664 and the cut-off value was 43.5°.

Conclusions

PUA has a significant association with symptom severity and Qmax among prostatic anatomical factors analyzed in men with LUTS and small PV. PUA should be considered as an important clinical factor in male LUTS management. Furthermore, the impact of PUA on response to medical treatment and disease progression needs to be investigated.  相似文献   
952.
Homogentisate solanesyltransferase (HST) plays an important role in plastoquinone (PQ) biosynthesis and acts as the electron acceptor in the carotenoids and abscisic acid (ABA) biosynthesis pathways. We isolated and identified a T-DNA insertion mutant of the HST gene that displayed the albino and dwarf phenotypes. PCR analyses and functional complementation also confirmed that the mutant phenotypes were caused by disruption of the HST gene. The mutants also had some developmental defects, including trichome development and stomata closure defects. Chloroplast development was also arrested and chlorophyll (Chl) was almost absent. Developmental defects in the chloroplasts were consistent with the SDS-PAGE result and the RNAi transgenic phenotype. Exogenous gibberellin (GA) could partially rescue the dwarf phenotype and the root development defects and exogenous ABA could rescue the stomata closure defects. Further analysis showed that ABA and GA levels were both very low in the pds2-1 mutants, which suggested that biosynthesis inhibition by GAs and ABA contributed to the pds2-1 mutants'' phenotypes. An early flowering phenotype was found in pds2-1 mutants, which showed that disruption of the HST gene promoted flowering by partially regulating plant hormones. RNA-sequencing showed that disruption of the HST gene resulted in expression changes to many of the genes involved in flowering time regulation and in the biosynthesis of PQ, Chl, GAs, ABA and carotenoids. These results suggest that HST is essential for chloroplast development, hormone biosynthesis, pigment accumulation and plant development.  相似文献   
953.
MIR34A (microRNA 34a) is a tumor suppressor gene, but how it regulates chemotherapy response and resistance is not completely understood. Here, we show that the microRNA MIR34A-dependent high mobility group box 1 (HMGB1) downregulation inhibits autophagy and enhances chemotherapy-induced apoptosis in the retinoblastoma cell. HMGB1 is a multifaceted protein with a key role in autophagy, a self-degradative, homeostatic process with a context-specific role in cancer. MIR34A inhibits HMGB1 expression through a direct MIR34A-binding site within the HMGB1 3′ untranslated region. MIR34A inhibition of HMGB1 leads to a decrease in autophagy under starvation conditions or chemotherapy treatment. Inhibition of autophagy promotes oxidative injury and DNA damage and increases subsequent CASP3 activity, CASP3 cleavage, and PARP1 [poly (ADP-ribose) polymerase 1] cleavage, which are important to the apoptotic process. Finally, upregulation of MIR34A, knockdown of HMGB1, or inhibition of autophagy (e.g., knockdown of ATG5 and BECN1) restores chemosensitivity and enhances tumor cell death in the retinoblastoma cell. These data provide new insights into the mechanisms governing the regulation of HMGB1 expression by microRNA and their possible contribution to autophagy and drug resistance.  相似文献   
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Previously, we demonstrated that the transient receptor potential vanilloid 4 (TRPV4) cation channel, a member of the TRP vanilloid subfamily, is one of the serum glucocorticoid-induced protein kinase1 (SGK1) authentic substrate proteins, and that the Ser 824 residue of TRPV4 is phosphorylated by SGK1 [1]. In this study, we demonstrated that phosphorylation on the Ser 824 residue of TRPV4 is required for its interaction with F-actin, using TRPV4 mutants (S824D; a phospho-mimicking TRPV4 mutant and S824A; a non-phosphorylatable TRPV4 mutant) and its proper subcellular localization. Additionally, we noted that the phosphorylation of the Ser824 residue promotes its single channel activity, Ca2 + influx, protein stability, and cell surface area (expansion of plasma membrane).  相似文献   
958.
Apoptosis, which is anti-inflammatory, and necrosis, which is pro-inflammatory, represent the extremes of the cell death spectrum. Cell death is complex and both apoptosis and necrosis can be observed in the same cells or tissues. Here, we introduce a novel combined mode of cellular demise – caspase-dependent regulated necrosis. Most importantly, it is mainly characterized with release of marked amount of oligo- or poly-nucleosomes and their attached damage-associated molecular patterns (DAMPs) and initiated by caspase activation. Caspase-activated DNase has dual roles in nucleosomal release as it can degrade extracellularly released chromatin into poly- or oligo-nucleosomes although it prohibits release of nucleosomes. In addition, osmotically triggered water movement following Cl influx and subsequent Na+ influx appears to be the major driving force for nucleosomal and DAMPs release. Finally, Ca2+-activated cysteine protease, calpain, is an another essential factor in nucleosomal and DAMPs release because of complete reversion to apoptotic morphology from necrotic one and blockade of nucleosomal and DAMPs release by its inhibition.Apoptosis is characterized by membrane blebbing, cellular shrinkage, nuclear condensation, nuclear fragmentations, oligo-nucleosomal DNA fragmentation and formation of apoptotic bodies. These characteristics are attributed mainly to the caspase family of cysteine proteases.1,2 Necrosis is distinguished from apoptosis by cellular swelling, plasma membrane rupture, absence of oligo-nucleosomal degradation and, finally, rapid lysis of cells and cellular constituents including damage-associated molecular patterns (DAMPs) are massively exuded extracellularly to activate inflammatory and immune responses. 3, 4, 5Calpains are a family of Ca2+-activated cysteine proteases consisting of 15 genes. Among them, μ-calpain (calpain I) and m-calpain (calpain II) are ubiquitously expressed in most cells as a heterodimer consisting of a large subunit (80 kDa; calpain 1 of μ-calpain and calpain 2 of m-calpain) and a common small subunit (29 kDa; calpain S1), which is processed into a smaller heterodimer (18–78 kDa) upon activation by Ca2+. Ubiquitous calpains are regulated by an endogenous inhibitor, calpastatin.6It has long been observed that both apoptosis and necrosis can be simultaneously detected in tissues or cell culture. Therefore, apoptosis and necrosis have been assumed to be two extremes of the cell death spectrum capable of inter-conversion by key regulators.5,7 In this study, we introduce a novel mode of cell death involving the combination of apoptosis and necrosis, being a caspase-dependent process with necrotic morphology, involving the active release of DAMPs bound to nucleosomes.  相似文献   
959.

The effects of ΔPb-CATH4, a cathelicidin derived from Python bivittatus, were evaluated against Staphylococcus aureus-infected wounds in mice. These effects were comparable to those of classical antibiotics. ΔPb-CATH4 was resistant to bacterial protease but not to porcine trypsin. A reduction in the level of inflammatory cytokines and an increase in the migration of immune cells was observed in vitro. Thus, ΔPb-CATH4 can promote wound healing by controlling infections including those caused by multidrug-resistant bacteria via its immunomodulatory effects.

  相似文献   
960.

Background

Excessive oxidative stress and lipid peroxidation have been demonstrated to play important roles in the production of liver damage. L-carnitine is a natural substance and acts as a carrier for fatty acids across the inner mitochondrial membrane for subsequent beta-oxidation. It is also an antioxidant that reduces metabolic stress in the cells. Recent years L-carnitine has been proposed for treatment of various kinds of disease, including liver injury. This study was conducted to evaluate the protective effect of L-carnitine against hydrogen peroxide (H2O2)-induced cytotoxicity in a normal human hepatocyte cell line, HL7702.

Methods

We analyzed cytotoxicity using MTT assay and lactate dehydrogenase (LDH) release. Antioxidant activity and lipid peroxidation were estimated by reactive oxygen species (ROS) levels, activities and protein expressions of superoxide dismutase (SOD) and catalase (CAT), and malondialdehyde (MDA) formation. Expressions of peroxisome proliferator-activated receptor (PPAR)-alpha and its target genes were evaluated by RT-PCR or western blotting. The role of PPAR-alpha in L-carnitine-enhanced expression of SOD and CAT was also explored. Statistical analysis was performed by a one-way analysis of variance, and its significance was assessed by Dennett''s post-hoc test.

Results

The results showed that L-carnitine protected HL7702 cells against cytotoxity induced by H2O2. This protection was related to the scavenging of ROS, the promotion of SOD and CAT activity and expression, and the prevention of lipid peroxidation in cultured HL7702 cells. The decreased expressions of PPAR-alpha, carnitine palmitoyl transferase 1 (CPT1) and acyl-CoA oxidase (ACOX) induced by H2O2 can be attenuated by L-carnitine. Besides, we also found that the promotion of SOD and CAT protein expression induced by L-carnitine was blocked by PPAR-alpha inhibitor MK886.

Conclusions

Taken together, our findings suggest that L-carnitine could protect HL7702 cells against oxidative stress through the antioxidative effect and the regulation of PPAR-alpha also play an important part in the protective effect.  相似文献   
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