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991.
目的:分析李发枝教授治疗艾滋病发热的用药规律,为中医药治疗艾滋病发热提供相应的用药参考依据。方法:利用复杂网络分析方法,研究河南尉氏县2007 年9 月~2012 年6 月期间接受李发枝教授治疗过的艾滋病发热患者,分析艾滋病发热的病因病机、名老中医辨证论治及用药规律。结果:运用多维检索查询分析得出,本次研究中治疗艾滋病发热的核心药物为柴胡、甘草、黄芩等和解清热药物及党参、黄芪等益气扶正之品;核心处方为小柴胡汤和补中益气汤加减。结论:李发枝教授治疗艾滋病发热以清热兼补中益气为治则。  相似文献   
992.
中医舌象信息采集与分析新进展   总被引:5,自引:0,他引:5  
基于数字图像技术的中医舌诊现代化研究已经取得了很大进展,实现了舌象信息的获取,舌色、苔色、苔厚、腐腻、裂纹、润燥等舌象指标的自动分析。为了克服现有舌象采集平台体积大的缺点,我们研制了新型舌象采集装置;舌象特征分析方面,对舌动态特征以及舌脉特征进行了初步探索;将现代信息融合技术应用于对中医舌象信息的融合上,进行了相关实验。本文简要阐述了这些舌象信息采集与分析研究的新进展。  相似文献   
993.
目的 观察普济宣肺消毒饮对急性支气管炎化痰作用.方法 用随机、对照、前瞻性研究方法,将87例急性支气管炎(表寒里热证)患者随机分为治疗组44例和对照组43例,治疗组服用普济宣肺消毒饮,对照组用急支糖浆治疗,观察对咯痰的影响,疗程为7d.结果 治疗组对咯痰、发热、头痛、恶风等症状有明显治疗作用,治疗后咯痰疗效和评分低于对照组,化痰疗效优于对照组(P<0.05).结论 普济宣肺消毒饮有一定的化痰作用.  相似文献   
994.
目的 :研究桂枝汤对体温双向调节作用与下丘脑PGE2 含量及COX活性的关系。方法 :采用放免法对下丘脑中PGE2 含量及COX活性进行同步检测。结果 :在酵母诱导发热大鼠中 ,桂枝汤可使下丘脑中PGE2 含量明显降低 (P <0 .0 5) ,而在安痛定诱导的低体温大鼠中 ,它可使PGE2 含量明显增高 (P <0 .0 5)。在两种模型中 ,桂枝汤对下丘脑细胞中COX活性的影响均不明显 (P >0 .0 5)。结论 :桂枝汤对体温的双向调节作用可能部分是通过影响PGE2 含量来实现的 ,但PGE2 含量增减不依赖于下丘脑细胞中COX活性的变化。  相似文献   
995.
目的 探讨药物基因检测下使用文拉法辛治疗抑郁症的效果和安全性,为个体化用药提供参考.方法 纳入符合《国际疾病分类(第10版)》(ICD-10)抑郁发作诊断标准的66例患者为研究对象.将药物基因检测报告建议并选用文拉法辛治疗的患者分为研究组(n=32),医生与患者协商后决定使用文拉法辛治疗的患者为对照组(n=34).于治...  相似文献   
996.
Amide is a fundamental group that is present in molecular structures of all domains of organic chemistry and the construction of this motif with high atom economy is the focus of the current research. Specifically, N-methyl amides are valuable building blocks in natural products and pharmaceutical science. Due to the volatile nature of methyl amine, the generation of N-methyl amides using simple acids with high atom economy is rare. Herein, we disclose an atom economic protocol to prepare this valuable motif under DABCO/Fe3O4 cooperative catalysis. This protocol is operationally simple and compatible with a range of aliphatic and (hetero)aromatic acids with very good yields (60–99%). Moreover, the Fe3O4 can be easily recovered and high efficiency is maintained for up to ten cycles.

The generation of N-methyl amides using simple acids with high atom economy is rare owning to the volatile nature of methyl amine. Herein, an atom economic protocol was disclosed to prepare this valuable motif under DABCO/Fe3O4 cooperative catalysis.

Amide is a fundamental group that is present in molecular structures of all domains of organic chemistry.1 It is widely distributed in natural products, synthetic drugs and functional polymers, and is also the key chemical connection in proteins.2 It has been shown that amide bond formation alone accounts for 65% of all preliminary screening reactions in the pharmaceutical industry.3 This means the generation of amide bonds with high atom efficiency is of high practical importance. And not surprisingly, ‘amide formation avoiding poor atom economy reagents’ was voted as the top challenge for organic chemistry by the ACS Green Chemistry Institute in 2007.3From synthetic point of view, the ideal way to produce amide bonds would be the direct coupling of readily available carboxylic acids and amines, but this process is thermodynamically unfavourable due to the formation of the corresponding carboxylate-ammonium salt,4 therefore, stoichiometric amount of coupling reagents, such as DCC, DIC, EDCI, HATU, HBTU, HCTU, SOCl2, BOP, acid chloride etc, are generally required to sidestep thermal conditions for amide bond formation.5 These reagents are highly successful, but the process generally suffers from poor atom economy and side products removal issue especially in the large-scale applications.5 To overcome these drawbacks, “nonclassical” amide bonds formation routes were investigated.6 In these processes, the catalyst takes the role of a coupling reagent in generating an active ester suitable for amidation in a waste-free manner. However, these processes have not been applied in the preparation of N-methyl amides, probably because the methyl amine was delivered in its hydrochloride salt, alcoholic or aqueous form due to its volatile nature.On a different note, N-methyl amides are extensively presented in numerous natural products and pharmaceutical molecules, as shown in Fig. 1,7 and the methylation of amides is a promising way to improve the pharmacological property of molecules.8 However, the synthesis of N-methyl amides compounds relies heavily on non-catalytic approaches.5,9 Catalytic approaches were also investigated by Hisaeda,10 Kundu,11 Li,12 Guo,13 Yu,14 Maruoka,15 Wang,16 Chen,17 Lamaty18 and their co-workers starting from nitriles, primiary amides, aldoximes, aldehydes, lignin, carbamoylsilane and alcohols. Until recently, Thakur,19 Marce,20 Sadeghzadeh21 and their co-workers developed elegant N-methyl amidation approach starting from carboxylic acids under nano-MgO, diatomite Earth@IL/ZrCl4 and Mg(NO3)2·6H2O catalysis respectively, while limitations like poor substrate scope or sophisticated tailored catalyst still persist. Mindful of all the above issues, developing an N-methyl amidation process of simple carboxylic acids, which is still of great challenge in synthesis, and establishing a broad (hetero)aryl scope with high atom economy from commercial available reagents and catalysts were critical considerations in this study. Moreover, the significance of N-methyl amides combined with our interests in the development of green synthetic approaches motivated us to explore the direct coupling of the carboxylic acids and isothiocyanates. To the best of our knowledge, this is the first successful work using isothiocyanatomethane to prepare N-methyl amides.Open in a separate windowFig. 1Marketed drugs bearing N-methyl amide group.Our initial investigation begins with phenylacetic acid and isothiocyanatomethane as model substrate for condition optimization. Using acetonitrile as solvent, only trace amount of product was detected under catalyst free or p-toluenesulfonic acid (PTSA) catalysis conditions (
EntryAdditiveTime (h)CatalystYield (%)
1245
224PTSA
348TEA17
448DBU45
548DMAP43
648DBN51
748DABCO65
8LiBr48DABCO71
9Mn(OAc)248DABCO75
10MnO48DABCO79
11MgO48DABCO88
12Al2O348DABCO85
13Fe3O448DABCO98
14Fe3O424DABCO75
15bFe3O448DABCO80
Open in a separate windowaReactions were run on 1 mmol 1a and 1.1 mmol 2a with 10 mol% catalyst and 10 mol% additive in 1 mL of MeCN at 85 °C for 48 hours unless otherwise noted.bReaction was conducted at 60 °C.Firstly, different acids were employed to react with isothiocyanatomethane and the results were summarized in Open in a separate windowaReactions were run on 1 mmol 1 and 1.1 mmol 2 with 10 mol% DABCO and 10 mol% Fe3O4 in 1 mL of MeCN for 48 hours at 85 °C unless otherwise noted.Subsequently, aromatic and heteroaromatic acids were tested for their compatibility with current reaction conditions and the results were summarized in Fig. 1) respectively, and all could be convenient prepared using current procedure with excellent yields.Substrate scope for the amidation reactiona
Open in a separate windowaReactions were run on 1 mmol 1 and 1.1 mmol 2 with 10 mol% DABCO and 10 mol% Fe3O4 in 1 mL of MeCN for 48 hours at 85 °C unless otherwise noted.Furthermore, to demonstrate the synthetic utilization of our methodology, the preparation of bioactive compounds was demonstrated Scheme 1. Compounds 3as is a patent HDAC4 inhibitor.22 Under the standard reaction conditions, 3as could be obtained from commercial available 1as in 92% yield. Our procedure is much more atom economy as it excluded the usage of activating reagent and excess amount of base. In a recent report, Yang group reported their pilot-scale synthesis of substituted phenylacetamides to tetrahydroisoquinoline-2-ones.23 In their practice, corrosive thionyl chloride was applied as activating reagent and large excess amount of methyl amine was required, however, moderate yield of 3a was obtained, while our method can achieve better yield along with the exclusion of corrosive thionyl chloride. Following this report, tetrahydroisoquinoline-2-one 4a could be obtained in 82% yield, which could be used in the preparation of various bioactive 4-aryl-tetrahydroisoquinolines 5a with known procedure.24Open in a separate windowScheme 1Application of N-methyl amide.Finally, owing to the magnetic nature of Fe3O4, we try to recover the Fe3O4 from the reaction system and test its efficiency. As the Fe3O4 is always stick to the magnetic stir bar, after the termination of the reaction, the reaction solution was pour out and the tub along with the magnetic stir bar was rinsed with MeCN three times, oven dried and used for the next cycle. The results shown that the Fe3O4 could be used 10 times and still maintained very good efficiency (Fig. 2).Open in a separate windowFig. 2The efficiency of recovered Fe3O4.Combined with the literature reports and experimantal observation,25 a plausable mechanism was proposed in Scheme 2. Firstly, the carboxylic acid reacts with the Fe3O4 to get iron (II and III) carboxylate A, which will coordinate to the intermediate B generated from DABCO and isothiocyanate to get intermediate C. Then, one of the carboxylate attack intermediate B to release DABCO and generates intermediate D. Intermediate D go through an intramolecular addition to generate intermediate E, which go through a rearrangement reaction to get intermediate F with the release of carbonyl sulfide. Finally, the protonation of F with carboxylic acid to get the final product and regenerate the iron (II and III) carboxylate A.Open in a separate windowScheme 2Proposed reaction mechanism.  相似文献   
997.
Spitz痣的病理特点及诊断     
王艳青  郭莹 《中华皮肤科杂志》2021,54(4):308-312
Spitz痣的诊断主要依据病理改变。本文作者结合在Ackerman皮肤病理学院的学习体会,详细分析Spitz痣病理结构特征、细胞学特征以及机体对Spitz痣的反应,希望有助于临床医师对Spitz痣的病理诊断和鉴别诊断。  相似文献   
998.
Elevation of Serum Spermidine in Obese Patients: Results from a Cross-Sectional and Follow-Up Study     
Hanshu Gao  Qianlong Zhang  Jiahui Xu  Wei Yuan  Ruixue Li  Hui Guo  Cuiying Gu  Wenjing Feng  Yanan Ma  Zhaoqing Sun  Liqiang Zheng 《Nutrients》2022,14(13)
Background: Spermidine, a natural polyamine, appears to be a promising intervention for the treatment of obesity in animal studies, but epidemiological studies on the association between spermidine and obesity are inadequate. Methods: In the cross-sectional study, a total of 4230 eligible Chinese rural participants aged ≥ 35 years at baseline were recruited, of whom 1738 completed the two-year follow-up. Serum spermidines were measured using high-performance liquid chromatography with a fluorescence detector. Obesity and change in BMI were used as outcomes. Multivariable logistic regression analysis was applied to obtain the odds ratios (ORs) and 95% confidence intervals (CIs). Results: Participants who were obese had higher serum spermidine concentrations than those who were of normal weight (median (IQR), 27.2 ng/mL (14.8–53.4 ng/mL) vs. 23.8 ng/mL (12.8–46.6 ng/mL), p = 0.002). Compared with participants in the first quartile, those in the third quartile (OR 1.327, 95% CI 1.050 to 1.678) and the fourth quartile (OR 1.417, 95% CI 1.121 to 1.791) had a significantly increased risk of prevalent obesity after adjustment for confounding factors. In the follow-up study, participants in the third quartile (OR 0.712, 95% CI 0.535 to 0.946) and the fourth quartile (OR 0.493, 95% CI 0.370 to 0.657) had significantly lower risks of an increase in BMI after adjustment for confounding factors, with the lowest quartile as the reference. Meanwhile, we found a nonlinear relationship between spermidine and BMI in the follow-up study (p < 0.001). Conclusions: Serum spermidine was positively associated with increased odds of obesity in the cross-sectional study but reduced odds of an increase in BMI in the follow-up study among Chinese adults. Future studies are warranted to determine the exact mechanism underlying the association between spermidine and obesity and the scope for interventions.  相似文献   
999.
GOS Ameliorates Nonalcoholic Fatty Liver Disease Induced by High Fat and High Sugar Diet through Lipid Metabolism and Intestinal Microbes     
Shuting Qiu  Jiajia Chen  Yan Bai  Jincan He  Hua Cao  Qishi Che  Jiao Guo  Zhengquan Su 《Nutrients》2022,14(13)
The treatment of nonalcoholic fatty liver disease (NAFLD) remains very challenging. This study investigated the therapeutic effect of galactose oligosaccharide (GOS), an important prebiotic, on NAFLD through in vivo and in vitro experiments and preliminarily explored the mechanism by which GOS improves liver lipid metabolism and inflammation through liver and intestinal microbiological analysis. The results of mouse liver lipidomics showed that GOS could promote body thermogenesis in mice with high-fat and high-sugar diet (HFHSD)-induced NAFLD, regulate lipolysis in liver fat cells, and accelerate glycine and cholesterol metabolism. GOS dose-dependently reduced the contents of total cholesterol (TC) and triglyceride (TG) in cells and reduced the accumulation of lipid droplets in cells. GOS also reduced the Firmicutes/Bacteroidetes ratio and altered the composition of the intestinal microbiota in mice fed a HFHSD. GOS can improve liver lipid metabolism and intestinal structure of NAFLD. These results provide a theoretical and experimental basis supporting the use of GOS as a health food with anti-NAFLD functions.  相似文献   
1000.
多节段布鲁菌性脊柱炎与脊柱结核MRI特征分析     
伍彦辉  董春娇  赵国芳  郭立杰  赵辉  邢卫红 《临床荟萃》2021,36(4):348-352
目的 探讨多节段布鲁菌性脊柱炎(BS)及脊柱结核(ST)在MRI中的不同影像特点,从而提高早期诊断及鉴别诊断水平.方法 回顾性分析33例由临床或病理确诊为多节段BS患者、30例多节段ST患者,根据两者MRI表现,分析其发生部位、椎体形态、周围组织情况及伴随征象.结果 多节段BS患者的椎体形态、椎间盘受累、后凸畸形、死骨...  相似文献   
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