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91.
Phenylhydrazine (PHZ) oxidation resulting in free iron release followed by free radical generation has increased frequency of cancer. This study aims towards the dose-dependent response of PHZ and the role of melatonin in comparison with vitamin E following PHZ-induced toxicity within the lymphoid tissue (spleen) of Indian tropical seasonal breeder, Funambulus pennanti, during reproductively active phase. An increase in the damages in terms of lipid peroxidation (LPO), apoptosis percentage, and splenomegaly was observed following different doses of PHZ treatment, i.e., 0.025, 0.5, and 1 mg/100 g body weight (b.wt.), where dose of 1 mg/100 g b.wt. showed more significant damages. Both melatonin (0.5 mg/100 g b.wt.) and vitamin E (1 mg/100 g b.wt.) administration ameliorated oxidative damages of 1 mg/100 g b.wt. PHZ-treated group. Melatonin altered PHZ-induced responses significantly to a greater degree than vitamin E as evidenced by LPO status, SOD activity, and ABTS radical cation scavenging activity of antioxidants. Thus, melatonin might be able to restrict carcinogenic property of PHZ-induced oxidative stress by protecting macromolecules of the cell from harmful effects of PHZ and instead preserving cell viability.  相似文献   
92.
This study reports the presence of a high molecular weight protein (Bengalin) from the Indian black scorpion (Heterometrus bengalensis) venom having antiosteoporosis activity in experimental osteoporosis developed in female albino Wister rats. Bengalin was purified through DEAE-cellulose ion exchange chromatography and high performance liquid chromatography. The molecular weight of the Bengalin was found to be 72 kDa and the first 20 amino acid sequence was found to be G-P-L-T-I-L-H-I-N-D-V-H-A-A/R-F-E-Q/G-F/G-N-T. Bengalin exhibited significant antiosteoporosis activity in experimental female rats, which was confirmed through analysis of urine Ca2+, PO43?, CRE & OH-P. Bengalin (3 μg and 5 μg/100 g rat/i.p.) antagonized osteoporosis by restoring urinary Ca2+, PO43?, CRE and OH-P, serum/plasma Ca2+, PO43?, ALP, TRAP, PTH, T3, TSH, Osteocalcin, IL1, IL6 and TNF α and bone minerals Ca2+, P, Mg2+, Zn2+, Na+, as compared with the sham operated control rats. Bone minerals density of osteoporosis female rats was improved due to Bengalin, observed through DEXA scan. Subacute toxicity studies in male albino mice, Bengalin showed cardiotoxicity. In vivo experiments, Bengalin showed cardiotoxicity on isolated guinea pig heart, guinea pig auricle, and neurotoxicity on isolated rat phrenic nerve diaphragm preparation. Further detail studies on the toxicity, antiosteoporosis and structural identity of Bengalin are warranted.  相似文献   
93.
The present study assessed the triterpenoid fraction from T dioica root (CETD) for antiproliferative effect and antioxidant influence against Ehrlich ascites carcinoma (EAC) in Swiss albino mice. Twenty-four hours after intraperitoneal inoculation of tumor (EAC) cells in mice, CETD was administered at 2 and 4 mg/ kg body weight daily for 9 consecutive days. On the 10th day, half of the mice were sacrificed for estimation of tumor proliferation, haematological, and hepatic antioxidative parameters viz. lipid peroxidation, reduced glutathione (GSH), glutathione-S-transferase (GST), superoxide dismutase(SOD)and catalase (CAT); the rest were kept alive for assessment of survival parameters. The antiproliferative effect of CETD was assessed by evaluating tumor weight, tumor volume, packed cell volume, viable and non-viable tumor cell counts, mean survival time and percentage increase in life span of EAC-bearing mice. CETD exhibited dose dependent and significant (p < 0.001) decreases in tumor weight, tumor volume, packed cell volume and viable cell count and extended the life span of EAC-bearing mice. Hematological profiles were significantly (p < 0.001) normalized in CETD treated mice as compared to EAC control. CETD treatment significantly (p < 0.001) modulated the aforementioned hepatic antioxidative parameters as compared to EAC control. The present study demonstrated that CETD possessed promising antiproliferative efficacy against EAC in mice, plausibly mediated by alleviation of oxidative stress by multiple mechanisms.  相似文献   
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96.
Parry Romberg's syndrome is an uncommon disorder characterized by atrophy of skin and subcutaneous tissue of one side of face. It has neurologic sequel. The commonest of which is epilepsy. Here, we present a 17-year old girl with features of Parry Romberg's disease with intractable epilepsy. Her seizures have stopped with systemic corticosteroids. This treatment response, together with previous reports is suggestive of an autoimmune basis to this disorder. Thus the epilepsy in some such cases may be steroid responsive.  相似文献   
97.
Synovial sarcoma is an aggressive soft-tissue malignancy marked by a unique t(X;18) translocation leading to expression of a chimeric SYT-SSX fusion protein. We report here a mouse model of synovial sarcoma based on conditional expression of the human SYT-SSX2. Using this model, we have identified myoblasts as a potential source of synovial sarcoma. Remarkably, within the skeletal muscle lineage, while expression of the oncoprotein in immature myoblasts leads to induction of synovial sarcoma with 100% penetrance, its expression in more differentiated cells induces myopathy without tumor induction. We also show that early widespread expression of the fusion protein disrupts normal embryogenesis, causing lethality.  相似文献   
98.
Anatomically constrained reconstruction from noisy data.   总被引:1,自引:0,他引:1  
Noise is a major concern in many important imaging applications. To improve data signal-to-noise ratio (SNR), experiments often focus on collecting low-frequency k-space data. This article proposes a new scheme to enable extended k-space sampling in these contexts. It is shown that the degradation in SNR associated with extended sampling can be effectively mitigated by using statistical modeling in concert with anatomical prior information. The method represents a significant departure from most existing anatomically constrained imaging methods, which rely on anatomical information to achieve super-resolution. The method has the advantage that less accurate anatomical information is required relative to super-resolution approaches. Theoretical and experimental results are provided to characterize the performance of the proposed scheme.  相似文献   
99.
There is great need to identify and characterize drug targets and chemotherapeutic strategies against malaria. Here we show that a vacuolar-network induced by the human malaria parasite Plasmodium falciparum, is a major import pathway for artemisinin, a leading, new anti-malarial that is known to be effective against drug resistant strains. We also show that artemisinin-treatment induces aberrant, budding of a vacuolar-network membrane protein and its antimalarial activity is additive with toxic sphingolipid analogues that block the network. The data suggest that artemisinin alters membrane protein export from the vacuolar-network and combinations with anti-network reagents have the potential to provide powerful new chemotherapy for drug resistant malaria.  相似文献   
100.

Purpose  

New antiviral agents were prepared by attaching derivatives of sialic acid (1) and of the drug zanamivir (2) to poly(isobutylene-alt-maleic anhydride) (poly-(1 + 2)) or by mixing poly-1 and poly-2, followed by assaying them against wild-type and drug-resistant influenza A Wuhan viruses.  相似文献   
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