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61.
The loss of genetic diversity poses a serious threat to the conservation of endangered species, including wild felids. We are attempting to develop spermatogonial stem cell transplantation in the cat as a tool to preserve and propagate male germ-plasm from genetically valuable animals, be they threatened wild species or lines of cats used as models for inherited diseases. In this study, we investigated the use of local external beam radiation treatment to deplete the endogenous germ cells of male domestic cats, a step necessary to prepare them for use as recipients for transplantation. Testes of 5-month-old domestic cats were irradiated with a fractionated dose of 3 Gy per fraction for 3 consecutive days. These cats were castrated at 2, 4, 8, 16, and 32 weeks posttreatment, and progress of spermatogenesis was evaluated histologically and compared against age-matched controls. Even at the latest time points, less than 10% of tubules contained germ cells at any stage of meiosis, showing the efficacy of this protocol. In addition, male germ cells were isolated from the testes of domestic cats using a 2-step enzymatic dissociation to establish a protocol for the preparation of donor cells. The presence and viability of spermatogonia within this population were demonstrated by successful transplantation into, and colonization of, mouse seminiferous tubules. The success of these protocols provides a foundation to perform spermatogonial stem cell transplantation in the domestic cat.  相似文献   
62.
Previous studies have shown that patients with chronic obstructive pulmonary disease (COPD) who undergo surgical revascularization have higher in-hospital mortality rates. Limited data are available on the outcomes of patients with COPD undergoing percutaneous coronary intervention (PCI). Our study evaluated the association between COPD and in-hospital and long-term mortality in patients undergoing PCI. We studied 10,994 patients who underwent PCI from 1997 to 2003 at our institution (1,117 with and 9,877 without COPD). A patient was considered to have COPD if it was listed as a co-morbid condition in our database. The primary end point was all-cause mortality. Cox logistic regression models were used to determine whether COPD was an independent predictor of all-cause mortality after PCI. The mean age of the study population was 64 years, and 70.2% were men. Significantly more patients with COPD died in hospital (2.9% vs 1.2%, p <0.0001). The median follow-up was 33 months; 89.6% of patients without COPD versus 75.6% of patients with COPD (log-rank 280, degree of freedom 1, p <0.0001) were alive at the end of the follow-up. After adjusting for other variables known to increase mortality, COPD was a significant independent predictor of in-hospital death (odds ratio 2.51, 95% confidence interval 1.45 to 4.35, p = 0.001) and long-term mortality (hazard ratio 2.16, 95% confidence interval 1.81 to 2.56, p <0.0001) after PCI. In conclusion, patients with a history of COPD have higher in-hospital and long-term mortality rates than those without COPD after PCI.  相似文献   
63.
64.
BACKGROUND: The effect of reactive oxygen species (ROS) on insulin action is unclear. This study was carried out to explore the effect of prolonged low grade oxidative stress and vitamin E treatment on cultured rat L6 muscle cells. METHODS: L6 myotubes were incubated with vitamin E for 18 h and treated with H2O2 generating system for 12 h. Insulin stimulated glucose uptake, total antioxidant capacity and reduced glutathione concentration were measured. RESULTS: There was a marked decrease in insulin stimulated glucose transport in L6 cells exposed to H2O2 generating system. Pretreatment with vitamin E attenuates the effect of H2O2 on insulin action. Treatment with H2O2 caused a significant reduction in the levels of reduced glutathione and total antioxidant capacity, these alterations were reversed by vitamin E pretreatment. Vitamin E per se had no effect on insulin stimulated glucose transport in cells not exposed to oxidative stress. CONCLUSION: In conclusion, our observations indicate that vitamin E improves the free radical defense system potential and prevents oxidative stress induced insulin resistance in rat L6 muscle cells.  相似文献   
65.
66.
Spherical gold nanoparticles of approximately 16 nm were synthesized using a sonochemical reduction method and characterized using UV–vis spectroscopy, atomic force microscopy (AFM) and transmission electron microscopy (TEM). The binding of these gold nanoparticles with bovine serum albumin (BSA) and human serum albumin (HSA) was investigated using UV–vis absorption and fluorescence spectroscopic techniques. A strong quenching of the fluorescence from serum albumins was observed due to the formation of a ground state complex with gold nanoparticles (static quenching). The fluorescence quenching constants, number of binding sites and binding constants were determined using Stern–Volmer and Benesi–Hildebrand plots. Using Forster Resonance Energy Transfer (FRET) theory, the distance between the donor (serum albumins) and acceptor (gold nanoparticles) was obtained, which showed that HSA has more affinity towards sonochemically synthesized gold nanoparticles compared to gold nanoparticles synthesized using other methods.  相似文献   
67.
Pharmacological intervention to reduce CRC mortality entails the use of oral agents that can avert carcinogenesis. Silibinin, a major component of silymarin isolated from Silybum marianum (L.) was found to possess attractive remedial features. An in vivo study was designed to elucidate the effect of silibinin on the formation of 1, 2 dimethylhydrazine (DMH) induced aberrant crypt foci (ACF), tissue lipid peroxidation (LPO) and enzymic antioxidants status during different phases of experimental colon cancer. DMH alone treated rats showed significantly (p < 0.05) increased size and number of ACF, accompanied by decreased LPO and enzymic antioxidant activities. Administration of silibinin to DMH treated rats inhibited mean colonic ACF and multi-crypt AC/foci and also improved the levels of enzymic antioxidants in a time dependent manner. Histologically no obvious sign of neoplasia was observed in silibinin supplemented DMH treated rats during the various stages of carcinogenesis. Our results show that silibinin possesses potent chemopreventive activity against colon carcinogenesis.  相似文献   
68.

Objective

To evaluate the antioxidant activity of alcoholic leaf-extract of Solanum surattense (Solanaceae) (S. surattense).

Methods

Leaf extract were tested for in vitro free radical scavenging assays, such as hydroxyl radical and hydrogen peroxide, inhibition of superoxide anion radical and 2, 2-diphenyl-1-picryl hydrazyl radical (DPPH), total antioxidant activity and reducing ability. Further, total phenolic content of S. surattense was analyzed.

Results

S. surattense extract effectively scavenged free radicals at all different concentrations and showed its potent antioxidant activity. Further, these effects were in a dose dependent manner. Results were compared to standard antioxidants such as butylated hydroxytoluene, ascorbic acid and α-tocopherol.

Conclusions

S. surattense have strong antioxidant potential. Further the study validates the therapeutic benefits of the Indian system of medicine.  相似文献   
69.
A three-dimensional quantitative structure–activity relationship of 66 structurally and functionally diverse series of 1-substituted imidazoles with antifungal activity was studied using the CoMSIA method. The compounds were divided into a training set of 56 molecules and a test set of 10 molecules. The optimum CoMSIA model obtained for the training set were all statistically significant with cross-validated coefficients (q 2) of 0.725 and conventional coefficients (r ncv 2 ) of 0.998. The predictive ability of CoMSIA was determined using a test set of ten imidazole derivatives. CoMSIA model (Model 1) obtained from steric, electrostatic, and H-bond acceptor fields were found to have best predictivity with a predictive correlation coefficient (r pred 2 ) of 0.60. Based upon the information derived from CoMSIA, it is evident that steric, electrostatic, and hydrogen bond acceptor groups may be important for the design of more potent imidazole analogs as potent Candida P450DM inhibitors.  相似文献   
70.
IS6110 sequence based polymerase chain reaction (PCR) was compared with conventional bacteriological techniques in the laboratory diagnosis of extra-pulmonary tuberculosis (EPTB). One hundred and ninety one non-repeated clinical samples of EPTB and 17 samples from non-tuberculous cases as controls were included. All the samples were processed for Ziehl-Neelsen staining for acid fast bacilli (AFB) and 143 samples were processed by culture for M. tuberculosis . All the samples were processed for PCR amplification with primers targeting 123 bp fragment of insertion element IS6110 of M. tuberculosis complex. Of the total 191 samples processed, 34 (18%) were positive by smear for AFB. Culture for AFB was positive in 31(22%) samples among the 143 samples processed. Either smear or culture for AFB was found positive in 51(27%) samples. Of the total 191 samples processed 120 (63%) were positive by PCR. In 140 samples, wherein both the conventional techniques were found negative, 74 (53%) samples were positive by PCR alone. Among 51 samples positive by conventional techniques, 46 (90%) were found positive by PCR. PCR assay targeting IS6110 is useful in establishing the diagnosis of EPTB, where there is strong clinical suspicion, especially when the conventional techniques are negative.  相似文献   
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