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991.
OBJECTIVE: To examine whether genetic polymorphisms in CYP19 [intron 4 (TTTA)n; n = 7 to 13 and a 3-base pair deletion, which is in strong linkage disequilibrium with the seven repeat] and COMT (Val108/158Met) modified the change in BMI, total and percentage body fat, or subcutaneous and intra-abdominal fat during a year-long exercise intervention trial. These genes metabolize estrogens and androgens, which are important in body fat regulation. RESEARCH METHODS AND PROCEDURES: A randomized intervention trial was used, with an intervention goal of 225 min/wk of moderate-intensity exercise for one year. Participants (n = 173) were postmenopausal, 50 to 75 years old, sedentary, overweight or obese, and not taking hormone therapy at baseline. RESULTS: Exercisers with two vs. no CYP19 11-repeat alleles had a larger decrease in total fat (-3.1 kg vs. -0.5 kg, respectively, p = 0.01) and percentage body fat (-2.4% vs. -0.6%, respectively, p = 0.001). Exercisers with the COMT Met/Met vs. Val/Val genotype had a smaller decrease in percentage fat (-0.7% vs. -1.9%, respectively, p = 0.05). Among exercisers, women with the COMT Val/Val genotype and at least one copy of the CYP19 11-repeat allele vs. those with neither genotype/allele had a significantly larger decrease in BMI (-1.0 vs. +0.1 kg/m2, respectively, p = 0.009), total fat (-2.9 vs. -0.5 kg, respectively, p = 0.004), and percentage body fat (-2.6% vs. -0.4%, respectively, p < 0.001). DISCUSSION: Genetic polymorphisms in CYP19 and COMT may be important for body fat regulation and possibly modify the effect of exercise on fat loss in postmenopausal women.  相似文献   
992.
Background Although there were several clinical and experimental studies discussing the pathogenesis of dural arteriovenous fistula (DAVF), the pathological process leading to intracranial DAVF so far remains unknown. In this study, we investigated the expression of vascular growth factors in order to elucidate the possible role of these factors for the development of DAVF and to study the biological activity of this uncommon lesion.Methods We examined the histological features, proliferative and angiogenic capacities of the tissue specimens obtained from 6 patients who underwent surgery at our institution. Immunohistochemical staining for vascular endothelial growth factor (VEGF), its receptors FIk-1 and Fit-1, ephrin-B2, MIB-1 and proliferating cell nuclear antigen (PCNA) was performed using standard immunohistochemical techniques.Results A positive immunostaining was found for all antibodies studied except MIB-1, whereas nuclear endothelial expression of PCNA was observed in only 3/6 cases. VEGF stained positive in all of the available specimens (6/6). FIk-1 showed a positive immunoreaction in only 2/6 cases and Fit-1 in 4/6 cases. Ephrin-B2 was expressed in the majority (5/6) of the cases.Conclusions These results support the hypothesis that DAVFs might be acquired dynamic vascular malformations with low biological activity. Vascular growth factors like VEGF and ephrin-B2 might play a pivotal role in the formation of DAVF.  相似文献   
993.
己酮可可碱对外源性过敏性肺泡炎治疗作用的初步研究   总被引:1,自引:0,他引:1  
目的 通过研究己酮可可碱 (POF)对外源性过敏性肺泡炎 (EAA)患者肺泡巨噬细胞(AM)产生的细胞因子的作用 ,探讨其治疗EAA的可能性 ,并与地塞米松 (DEX)的作用进行比较。方法 入选EAA患者 9例 ,通过支气管肺泡灌洗收AM ,并以 10 %RPMI为培养液或 10 %RPMI加内毒素 (LPS ,10 0 μg/L) ;或分别加入浓度为 0 0 1mmol/L、0 1mmol/L、1mmol/L的POF ;或加入 0 1mmol/LDEX进行AM培养 2 4h。用ELISA方法测定培养上清液中细胞因子含量。结果 POF可抑制EAA患者AM自发释放的TNFα和IL 10 ,此作用有剂量依赖关系 (P <0 0 0 1和P <0 0 5 )。POF对其他自发释放的细胞因子则无影响。 0 1mmol/LDEX只抑制自发释放的TNFα(P <0 0 5 )。除IL 1β和可溶性肿瘤坏死因子受体外 ,POF和 0 1mmol/LDEX均抑制LPS刺激的其他细胞因子的释放 (P <0 0 0 1或P <0 0 1或P <0 0 5 )。结论 POF对EAA的炎症有一定的抑制作用 ,然而POF治疗EAA及其他肺部疾病的临床价值 ,需要进一步的临床试验来评价。  相似文献   
994.
In Germany during the past years about 200-250 HIV infected pregnant women delivered a baby per year, a number that is currently increasing. To determine the HIV-status early in pregnancy voluntary HIV-testing of all pregnant women is recommended in Germany and Austria as part of prenatal care. In those cases, where HIV infection was known during pregnancy, since 1995 the rate of vertical transmission of HIV was reduced to 1-2%. - This low transmission rate has been achieved by the combination of anti-retroviral treatment of pregnant women, elective caesarean section before onset of labor, anti-retroviral post exposition prophylaxis in the newborn and refraining from breast-feeding by the HIV infected mother. To keep pace with new results in research, approval of new anti-retroviral drugs and changes in the general treatment recommendations for HIV infected adults, in 1998 and 2001 an interdisciplinary consensus meeting was held. Gynaecologists, infectious disease specialists, pediatricians, pharmacologists, virologists and members of the German AIDS Hilfe (NGO) were participating in this conference to update the prevention strategies. A third update became necessary in 2003. The updating process was started in January 2003 and was terminated in July 2003. The guidelines provide new recommendations on the indication and the starting point for HIV-therapy in pregnancies without complications, drugs and drug combinations to be used preferably in these pregnancies and updated information on adverse effects of anti-retroviral drugs. Also the procedures for different scenarios and risk constellations in pregnancy have been specified again. - With these current guidelines in Germany and Austria the low rate of vertical HIV-transmission should be further maintained or even further lowered.  相似文献   
995.
AIMS: Chronic allograft nephropathy and/or calcineurin inhibitor toxicity are common problems after organ transplantation. The aim of this study was to examine the safety and efficacy of switching from a calcineurin inhibitor-based to a calcineurin inhibitor-free immunosuppressive regimen consisting of sirolimus and mycophenolate mofetil (MMF) late after renal transplantation. METHODS: Kidney biopsies were performed in renal-transplanted patients with increasing serum creatinine levels at least 6 months after transplantation (mean time +/- SD after renal transplantation: 76.4 +/- 50.4 months). Patients with no signs of acute rejection were switched to MMF (500-2,000 mg/day) in combination with a low dose of sirolimus (1 mg/day). Renal function, serum chemistry, blood trough levels of sirolimus and MMF, and blood pressure were monitored. RESULTS: 13 patients were investigated. During our observation period (mean observation time +/- SD: 11.2 +/- 5.9 months), an improvement in renal function was observed in 10/13 patients. In 3/13 patients, renal function deteriorated further and hemodialysis was initiated in 2 patients within the next 6 months. However, a serum creatinine concentration above 3.5 mg/dl was measured in 2 of those 3 patients prior to the switch of the immunosuppressive protocol. Administration of a low dosis of sirolimus (1 mg/day) led to relevant sirolimus (4.16 +/- 1.85 ng/ml) and MMF blood trough levels (month 1: 6.8 +/- 3.46; month 3: 4.67 +/- 1.78 mg/l). The following adverse events were observed: borderline acute rejection (1/11 patients), anemia responding to higher dosage of erythropoietin (3/11), hyperlipidemia (1/11), and urinary tract infections (4/11). CONCLUSIONS: Low-dose sirolimus therapy in combination with concentration-adjusted MMF therapy leads to improvement of organ function late after renal transplantation. The follow-up of those patients should include assessments of blood cell counts, serum lipids and urinalysis to recognize the possible side effects.  相似文献   
996.
Summary. In mammals the composition of milk changes during early lactation, with a rapid decline of fat-soluble vitamins and a continuous increase in total lipids. The mechanisms underlying this phenomenon are not well understood, but might involve selective mechanisms related to mammary uptake or secretion into the milk. Since carotenoids are specifically distributed among the lipoprotein fractions in plasma, the simultaneous determination of carotenoids in plasma, lipoprotein fractions and milk might offer an opportunity to gain insight into this phenomenon. In 21 healthy mothers carotenoids in plasma and lipoprotein fractions were investigated at day 2 and 19 and milk on day 4 and 19 after delivery. Plasma levels of -tocopherol and cholesterol as well as lutein, zeaxanthin and cryptoxanthin were significantly lower later in lactation (day 19) than shortly after birth (P < 0.01). The stage of lactation had no effect on the distribution of carotenoids and -tocopherol among the plasma lipoprotein fractions. In milk, triacylglycerol increased (P < 0.01). In contrast, levels of carotenoids, -tocopherol and vitamin A were highest in colostrum and declined (P < 0.01). Because the magnitude of decrease was not the same in all carotenoids, the carotenoid pattern changed substantially. In colostrum the carotenoid pattern resembled those of plasma and the low-density lipoprotein fraction. In mature milk it was similar to the pattern found in the high density lipoprotein fraction. Based on these observations a selective mechanism might be responsible for the transfer of these components in milk involving different lipoprotein fractions at specific times of lactation.  相似文献   
997.
998.
Several studies using microarrays have shown that changes in gene expression provide information about the mechanism of toxicity induced by xenobiotic agents. Nevertheless, the issue of whether gene expression profiles are reproducible across different laboratories remains to be determined. To address this question, several members of the Hepatotoxicity Working Group of the International Life Sciences Institute Health and Environmental Sciences Institute evaluated the liver gene expression profiles of rats treated with methapyrilene (MP). Animals were treated at one facility, and RNA was distributed to five different sites for gene expression analysis. A preliminary evaluation of the number of modulated genes uncovered striking differences between the five different sites. However, additional data analysis demonstrated that these differences had an effect on the absolute gene expression results but not on the outcome of the study. For all users, unsupervised algorithms showed that gene expression allows the distinction of the high dose of MP from controls and low dose. In addition, the use of a supervised analysis method (support vector machines) made it possible to correctly classify samples. In conclusion, the results show that, despite some variability, robust gene expression changes were consistent between sites. In addition, key expression changes related to the mechanism of MP-induced hepatotoxicity were identified. These results provide critical information regarding the consistency of microarray results across different laboratories and shed light on the strengths and limitations of expression profiling in drug safety analysis.  相似文献   
999.
1000.
This study evaluated the response of the Na(+)/H(+) exchanger (NHE) to dopamine D(1)- and D(2)-like receptor stimulation in immortalized renal proximal tubular epithelial cells and freshly isolated renal proximal tubules from the spontaneously hypertensive rat (SHR) and their normotensive controls (Wistar Kyoto rats; WKY). Stimulation of D(1)-like receptors with SKF 38393 attenuated NHE activity in WKY cells (IC(50)=151 nM), but not in SHR cells. Stimulation of D(2)-like receptors with quinerolane (IC(50)=120 nM) attenuated NHE activity in SHR cells, but not in WKY cells. Forskolin was equipotent in SHR and WKY cells in inhibiting NHE activity. The effect of SKF 38393 was abolished by overnight treatment of WKY cells with cholera toxin (CTX, 500 ng ml(-1)), but not with pertussis toxin (PTX, 100 ng ml(-1)). The effect of quinerolane (1 microm) was abolished by overnight treatment of SHR cells with PTX, but not with CTX. The D(3) receptor agonist 7-OH-DPAT (IC(50)=0.8 microM) attenuated NHE activity in SHR cells only. This effect was abolished by S-sulpiride and by overnight treatment with PTX. The D(4) receptor agonist RBI 257 did not affect NHE activity. The 7-OH-DPAT inhibited NHE activity in freshly isolated renal proximal tubules from 4- and 12-week-old SHR and 12-week-old WKY, but not in freshly isolated renal proximal tubules from 4-week-old WKY. It is concluded that D(3) receptors coupled to a G(i/o) protein play a role in the handling of tubular Na(+), namely through inhibition of the NHE activity, this being of particular relevance in the SHR, which fail to respond to D(1)-like dopamine receptor stimulation.  相似文献   
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