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981.
OBJECTIVE: Young boys at high risk for alcoholism by having a family history of alcoholism (FH+) have lower amplitude of the visual P300 event-related scalp potential. They have also been reported to have a slowing in the rate of P300 amplitude change during adolescence. The present study examined whether the change in P300 amplitude during adolescence in sons of alcoholics and nonalcoholics is affected by D2 dopamine receptor (DRD2) polymorphism. METHODS: P300 was elicited with a visual discrimination task from 71 adolescent sons of alcoholics and social drinkers (Time 1, T1). The task was readministered 2 years later (Time 2, T2). Comparisons were made between boys who had the DRD2 A1 allele (A1+) and boys who did not (A1-), and between boys with one or both parents being alcoholic (FH+) and boys having no alcoholic parents (FH-). RESULTS: Discrimination task accuracy was lowest in the highest risk group (A1+, FH+) at T1, and highest in the lowest risk group (A1-, FH-) at T2, producing a significant interaction of allelic group x family history group x session. Reaction time was faster at T2 than T1, and this effect was larger in FH-boys (125 ms) than FH+boys (40 ms). Overall, the behavioral results suggest mild performance deficits on the discrimination task are associated with higher risk for alcoholism. In both testing sessions, P300 attained larger amplitudes in sons of nonalcoholics than sons of alcoholics. At T2 compared to T1, both the latency and amplitude of the P300 were decreased. However, while the developmental P300 latency effect was equivalent in both the A1+ and A1- allelic groups, the P300 amplitude reduction during adolescence, measured both in response to targets and in target minus non-target subtraction waveforms, was only found in boys with the A1- allele. CONCLUSION: Differences in the developmental course of P300 amplitude over the course of adolescence are dependent on DRD2 polymorphism. SIGNIFICANCE: These results suggest the importance of genetic determinants of the dopaminergic system in understanding the P300 as a risk marker for substance abuse using an integrative developmental perspective.  相似文献   
982.
BACKGROUND: Combined tramadol/acetaminophen is used to treat pain related to osteoarthritis. However, adverse events (AEs) leading to discontinuation can occur. Dose titration may decrease the risk for AEs. OBJECTIVE: The aim of this study was to assess the effect of tramadol/acetaminophen titration on the development of AEs leading to treatment discontinuation in patients with knee osteoarthritis. METHODS: This 2-week, multicenter, randomized, double-blind, double-dummy, add-on study was conducted at 12 tertiary referral university hospitals in the Republic of Korea. Patients aged 35 to 75 years with knee osteoarthritis receiving a stable dose of NSAIDs and with a daily mean pain-intensity score of > or = 4 on a numeric rating scale (NRS) (0 = no pain to 10 = worst pain) during the 48 hours prior to enrollment were eligible. Patients were randomly assigned to receive 1 tablet of tramadol/acetaminophen 37.5/325 mg QD and 1 placebo BID for 3 days, followed by 1 active tablet BID and 1 placebo QD for 4 days, followed by 1 active tablet TID for 7 days (titration group) or 1 tablet of combined tramadol 37.5 mg/acetaminophen 325 mg TID for 14 days (nontitration group). The primary outcome measure was the rate of treatment discontinuation due to AEs. Secondary outcome measures were time to discontinuation due to AEs, prevalences and characteristics of AEs, decrease from baseline in pain intensity as measured on the NRS, and change in the Korean version of the Western Ontario and McMaster Universities (K-WOMAC) index score (scale: 0 = best to 100 = worst). RESULTS: A total of 250 patients were enrolled (92.0% female; mean [SD] age, 60.2 [7.8] years; mean [SD] weight, 60.0 [9.2] kg [range, 37.5-90.7 kg]; all Korean). The discontinuation rate was significantly lower in the titration group than in the nontitration group (10.5% vs 26.2%; P < 0.001). The Kaplan-Meier survival curve showed that the rates of discontinuation due to AEs were similar in the 2 groups up to day 2, but thereafter the discontinuation rate was significantly lower in the titration group. The most common AEs were nausea (12.1% and 24.6% in the titration and nontitration groups, respectively; P = 0.008), vomiting (4.0% and 17.2%; P < 0.001), and dizziness (9.7% and 22.1%; P = 0.005). No serious AEs were reported in either group. Tramadol/acetaminophen use was associated with a similar decrease from baseline in pain in both the titration and nontitration groups (mean [SD] Delta: NRS, -1.60 [1.62] vs -1.68 [1.58]; total K-WOMAC, -12.86 [13.73] vs -12.52 [16.58]). CONCLUSIONS: In this population of Korean patients with knee osteoarthritis pain managed with a stable dose of NSAIDs, titration of tramadol/acetaminophen over 12 days was associated with improved tolerability and a significantly lower discontinuation rate compared with nontitration. Both regimens significantly reduced from baseline associated with osteoarthritis.  相似文献   
983.
984.

Background

Rat liver epithelial (RLE) cells could inhibit the proliferation and invasiveness of hepatoma cells in vitro. This study is to understand the tropism and the effect of RLE cells on mouse hepatoma cells both in vitro and in vivo.

Methods

RLE cells were isolated from new-born rats and characterized their stem cell markers. Co-culture and HCC mouse model was established to detect therapeutic effect of RLE cells.

Results

RLE cells (including Thy-1+ RLE cells, Thy-1- RLE cells, RLE cells) displayed a selective tropism toward ML-1 hepatoma cells both in vitro and in vivo. They altered the gene expression of some cancer stem cell markers in the liver tumor.

Conclusion

Liver epithelial cells have a selective tropism toward HCC in vitro and in vivo. They could alter the gene expression of cancer stem cells.  相似文献   
985.
986.
Diallyl trisulfide (DATS), an active component of garlic oil, has attracted much attention because of its anticancer effect on several types of cancers. However, the mechanism of DATS-induced apoptosis of basal cell carcinoma (BCC) is not fully understood. In the present study, we revealed that DATS-mediated dose-dependent induction of apoptosis in BCC cells was associated with intracellular reactive oxygen species accumulation and disrupted mitochondrial membrane potential. Western analysis demonstrated concordant expression of molecules involved in mitochondrial apoptosis, including DATS-associated increases in phospho-p53, proapoptotic Bax, and decreases in antiapoptotic Bcl-2 and Bcl-xl in BCC cells. Moreover, DATS induced the release of cytochrome c, apoptosis-inducing factor, and HtrA2/Omi into the cytoplasm, and activated factors downstream of caspase-dependent and caspase-independent apoptosis, including nuclear translocation of apoptotic-inducing factor and endonuclease G and the caspase cascade. These results were confirmed by pretreatment with the antioxidant N-acetyl-L-cysteine and the caspase inhibitor (z-VAD-fmk), the latter of which did not completely enhance the viability of DATS-treated BBC cells. Exposure to DATS additionally induced endogenous endoplasmic reticulum stress markers and intracellular Ca2+ mobilization, upregulation of Bip/GRP78 and CHOP/GADD153, and activation of caspase-4. Our findings suggest that DATS exerts chemopreventive potential via ER stress and the mitochondrial pathway in BCC cells.  相似文献   
987.
988.
989.

Background  

The leaves of Strobilanthes crispus (S. crispus) which is native to the regions of Madagascar to the Malay Archipelago, are used in folk medicine for their antidiabetic, diuretic, anticancer and blood pressure lowering properties. Crude extracts of this plant have been found to be cytotoxic to human cancer cell lines and protective against chemically-induced hepatocarcinogenesis in rats. In this study, the cytotoxicity of various sub-fractions of dichloromethane extract isolated from the leaves of S. crispus was determined and the anticancer activity of one of the bioactive sub-fractions, SC/D-F9, was further analysed in breast and prostate cancer cell lines.  相似文献   
990.
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