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41.
目的通过考察不同pH值的无水乙醇对硝酸甘油注射液稳定性的影响,筛选出最适于硝酸甘油注射液生产的无水乙醇。方法用高温加热破坏试验及长期试验的方法研究硝酸甘油注射液的稳定性,考察指标pH值和含量。结论碱性杂质含量低的无水乙醇配制的硝酸甘油注射液稳定性最好,适于硝酸甘油注射液的生产。  相似文献   
42.
Although excessive alcohol consumption is by far the most frequent cause of recurrent acute pancreatitis (AP) cases, specific therapy is still not well established to prevent recurrence. Generally, psychological therapy (e.g., brief intervention (BI)) is the cornerstone of cessation programs; however, it is not yet widely used in everyday practice. We conducted a post-hoc analysis of a prospectively collected database. Patients suffering from alcohol-induced AP between 2016 and 2021 received 30 min BI by a physician. Patient-reported alcohol consumption, serum gamma-glutamyl-transferase (GGT) level, and mean corpuscular volume (MCV) of red blood cells were collected on admission and at the 1-month follow-up visit to monitor patients’ drinking habits. Ninety-nine patients with alcohol-induced AP were enrolled in the study (mean age: 50 ± 11, 89% male). A significant decrease was detected both in mean GGT value (294 ± 251 U/L vs. 103 ± 113 U/L, p < 0.001) and in MCV level (93.7 ± 5.3 U/L vs. 92.1 ± 5.1 U/L, p < 0.001) in patients with elevated on-admission GGT levels. Notably, 79% of the patients (78/99) reported alcohol abstinence at the 1-month control visit. Brief intervention is an effective tool to reduce alcohol consumption and to prevent recurrent AP. Longitudinal randomized clinical studies are needed to identify the adequate structure and frequency of BIs in alcohol-induced AP.  相似文献   
43.
Resistant bacteria prevail in most chronic skin wounds and other biofilm-related topical skin infections. Bacteriophages (phages) have proven their antimicrobial effectiveness for treating different antibiotic-resistant and multidrug-resistant bacterial infections, but not all phages are effective against biofilms. Phages possessing depolymerases can reach different biofilm layers; however, those that do not have depolymerase activity struggle to penetrate and navigate in the intricate 3D biofilm structure and mainly infect bacteria lodged in the outer biofilm layers. To address this, Pseudomonas aeruginosa phage vB_PaeM-SMS29, a phage with poor antibiofilm properties, was incorporated into polyvinyl alcohol (PVA, Mowiol 4:88) supplemented with 0.1% (v/v) of glycerol, and cast onto two different microneedle arrays varying in geometry. The dissolving microneedles were thoroughly characterized by microscopy, force-displacement, swelling, phage release and stability. Furthermore, 48 h-old biofilms were formed using the colony biofilm procedure (absence of broth), and the antibiofilm efficacy of the phage-loaded microneedles was evaluated by viable cell counts and microscopy and compared to free phages. The phages in microneedles were fairly stable for six months when stored at 4 °C, with minor decreases in phage titers observed. The geometry of the microneedles influenced the penetration and force-displacement characteristics but not the antimicrobial efficacy against biofilms. The two PVA microneedles loaded with phages reduced P. aeruginosa PAO1 biofilms by 2.44 to 2.76 log10 CFU·cm−2 at 24 h. These values are significantly higher than the result obtained after the treatment with the free phage (1.09 log10 CFU·cm−2). Overall, this study shows that the distribution of phages caused by the mechanical disruption of biofilms using dissolving microneedles can be an effective delivery method against topical biofilm-related skin infections.  相似文献   
44.
目的:探索凝胶材料配比对丁香罗勒油透皮凝胶体外透皮性能的影响。方法:以CMC-Na和PVA为辅料,制备丁香罗勒油透皮剂。采用改良Franz扩散池,以鼠背皮肤为屏障进行经皮渗透试验,以丁香酚含量为指标,通过气相色谱法检测丁香罗勒油的经皮渗透量。结果:CMC-Na和PVA总量对丁香罗勒油透皮能力有较大影响,以25%为最佳;CMC-Na和PVA的比例对丁香罗勒油透皮能力无影响,最佳比例4∶2。结论:丁香罗勒油透皮凝胶可极大地提高丁香罗勒油的药效。  相似文献   
45.
从催化剂活性组分、助剂、载体和还原方法等多方面综述了近年来肉桂醛多相选择性加氢制备肉桂醇的方法研究,探讨了肉桂醛加氢活性和肉桂醇选择性的影响因素,并展望了肉桂醛选择性加氢的发展前景。通过催化剂设计提高非贵金属催化剂的活性、选择性和稳定性,并进一步降低反应温度和压力是今后的研究方向。  相似文献   
46.
The role of moderate alcohol consumption in the evolution of NAFLD is still debated. The aim of this study is to evaluate the impact of current and lifelong alcohol consumption in patients with NAFLD. From 2015 to 2020, we enrolled 276 consecutive patients fulfilling criteria of NAFLD (alcohol consumption up to 140 g/week for women and 210 g/week for men). According to their current alcohol intake per week, patients were divided in: abstainers, very low consumers (C1: <70 g/week) and moderate consumers (C2). We created a new tool, called LACU (Lifetime Alcohol Consuming Unit) to estimate the alcohol exposure across lifetime: 1 LACU was defined as 7 alcohol units per week for 1 drinking year. Patients were divided into lifelong abstainers and consumers and the latter furtherly divided into quartiles: Q1-Q4. Stratification according to alcohol intake, both current and cumulative as estimated by LACU, showed that very low consumers (C1 and Q1-Q3) displayed lower frequency of cirrhosis and hepatocellular carcinoma compared to abstainers and moderate consumers (C2 and Q4). We can speculate that up to one glass of wine daily in the context of a Mediterranean diet may be a long-term useful approach in selected NAFLD patients.  相似文献   
47.
A magnesium phosphate cement-based engineered cementitious composite (MPC-ECC) was developed using polyvinyl alcohol (PVA) fibers and fly ash. In this study, the bond behavior of MPC-ECC with ordinary concrete was evaluated through single and double shear bond strength tests. The effects of the water to solid mass ratio (W/S), the sand to binder mass ratio (S/B), the molar ratio of MgO to KH2PO4 (M/P), the fly ash content (F), the borax dosage (B), the volume fraction of PVA fibers (Vf), and curing age on the bond behavior of MPC-ECC with ordinary concrete were examined. The results showed that as the W/S increased, the single and double shear bond strengths were gradually reduced. As the S/B increased, the double shear bond strength increased; the single shear bond strength first decreased up to an S/B of 0.1 and then increased. With the increase of M/P, the single and double shear bond strengths increased. With the increase of F, the single shear bond strength first increased up to an F of 30% and then decreased; the double shear bond strength decreased. With the increase of B, the single and double shear bond strengths increased first and then decreased, and their strength reached its maximum at a B of 6%. The increase of Vf improved the single and double shear bond strengths. The research results can provide some technical guidance for repairing concrete structures with MPC-ECC.  相似文献   
48.
  目的  探讨蝙蝠蛾拟青霉复合胶囊对四氯化碳与酒精所致小鼠急性肝损伤的保护作用。  方法  分别采用四氯化碳和酒精灌胃诱导小鼠急性肝损伤模型,测定四氯化碳急性肝损伤模型小鼠血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)的含量及酒精急性肝损伤模型小鼠肝组织中丙二醛(MDA)、甘油三酯(TG)、还原型谷胱甘肽(GSH)的含量并观察2组肝组织切片病理形态学变化。  结果  蝙蝠蛾拟青霉复合胶囊675、2 025 mg/kg BW 剂量组四氯化碳急性肝损伤小鼠血清的ALT、AST含量均低于模型对照组,差异具有统计学意义(P < 0.05)。急性酒精性肝损伤模型中,675、2 025 mg/kg BW剂量组的MDA含量和3个剂量组的TG含量明显低于模型对照组,675、2 025 mg/kg BW剂量组的GSH含量明显高于模型对照组,差异均具有显著性(P < 0.05)。小鼠肝组织形态学结果表明,四氯化碳肝损伤模型肝组织中、高剂量组的肝脏细胞坏死程度与模型对照组比较积分显著下降,差异具有显著性(P < 0.05),各剂量组气球样变积分和高剂量组水样变程度积分也较模型组有显著性降低(P < 0.01);蝙蝠蛾拟青霉复合胶囊能显著改善急性酒精性肝损伤小鼠肝细胞脂肪变性程度,差异具有显著性(P < 0.05)。  结论  蝙蝠蛾拟青霉复合胶囊对小鼠急性肝损伤具有较好的辅助保护功能。  相似文献   
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