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991.
Rationale and objective Although many contingencies operating in the natural environment include continuous dimensions of responses and reinforcers,
previous studies of drug self-administration have almost exclusively used discrete dimensions of responses (e.g., a lever
press) and reinforcers (e.g., 1.0 mg/kg/injection cocaine). Therefore, the present study provides an initial examination under
experimental conditions with both responses and reinforcers measured along continuous dimensions.
Materials and methods Cocaine-maintained responding was studied in rats under a novel, hold-down schedule of reinforcement wherein the duration
of the response was directly related to the magnitude of the reinforcer. These conditions were established by activating the
syringe pump when the lever was pressed down and turning the pump off when the lever was released. The concentration of cocaine
available in the syringe was varied across sessions.
Results Cocaine self-administration was readily maintained under these conditions and remained stable across sessions. Responding
was concentration dependent, with the number of responses and total duration of the response inversely related to concentration,
and overall session intake of cocaine was stable across concentrations. In general, the duration of the responses were less
than 0.5 s and did not vary as a function of concentration.
Conclusions Stability of responding under these schedule conditions was acquired quickly. This schedule of reinforcement may be useful
for comparing across drug classes, can be extended for use with other types of responses and reinforcers, and may be more
representative of the natural world where response-reinforcer contingencies are more likely to be experienced along continuous,
rather than discrete, dimensions.
Drake Morgan and Yu Liu contributed equally to this publication. 相似文献
992.
Kamalneet Kaur Vinod Kumar Vikas Beniwal Vikas Kumar Neeraj Kumar Vishal Sharma Sundeep Jaglan 《Medicinal chemistry research》2016,25(10):2237-2249
In search of a new class of biologically active agents, some novel oxazolidinone-thiazole hybrids 4a–m have been synthesized and characterized on the basis of a combined use of infrared, NMR (1H, 13C) spectroscopy, mass spectrometry and elemental analysis. All compounds were evaluated for their antimicrobial, antioxidant and ultraviolet mediated DNA damage protective activity. Among the series, compound 4i emerged as the most potent antimicrobial agent, particularly, against Bacillus subtilis, Candida albicans and Saccharomyces cerevisiae in comparison to the standard drugs, Ciprofloxacin (antibacterial) and Amphotericin-B (antifungal). Other promising antimicrobial agents including the compounds 4f–h. In addition, all compounds 4a–m were found to show very high DNA damage protecting ability under ultraviolet irradiation. The antioxidant study revealed that the compounds 4d and 4j were found as the most potent antioxidants as compared to ascorbic acid, a reference compound considered in the study. 相似文献
993.
Ali Najafi Ehsan Motaghi Mohammad Javad Hosseini Masoumeh Ghasemi-Pirbaluti 《Inflammopharmacology》2017,25(1):137-145
Ulcerative colitis is a chronic recurrent disease with incomplete treatment options. The current article evaluated the effect of sodium valproate on acetic acid-induced ulcerative colitis in rats. Rats were randomly distributed into six groups including Sham group, colitis control group, sodium valproate treatment groups (50, 100 and 300 mg/kg, i.p.) and dexamethasone-treatment group. Dexamethasone was used as a reference drug. Colitis was induced by intracolonic instillation of 2 mL of 3% acetic acid solution. The efficacy of sodium valproate was evaluated by macroscopical and histopathological scoring systems, hematocrit measurement as well as biochemical analysis including myeloperoxidase (MPO) and pro-inflammatory cytokines assessment. Sodium valproate, particularly with doses of 100 and 300 mg/kg significantly improved weight loss, and macroscopic damage, reduced ulcer area, colon weight, microscopic colitis index and elevated hematocrit level. Biochemical experiments showed elevated levels of colonic MPO activity, interleukin 1β (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) in colitis control group. Treatment with sodium valproate at the doses of 100 and 300 mg/Kg) decreased the MPO activity and colonic concentrations of IL-1β, IL-6 and TNF-α. The results provide evidence that sodium valproate has a protective effect in acetic acid-induced ulcerative colitis which might be due to its anti-inflammatory activities, and it may be useful in patients with ulcerative colitis. 相似文献
994.
目的:研究不同处理方法对卵白蛋白(Ovum Albumin,OVA)变应性鼻炎小鼠模型腹腔肥大细胞脱颗粒的影响。方法:将60只雌性小鼠随机分为5组,每组12只,分别按不同方法处理后分离各组小鼠的腹腔肥大细胞,中性红染色后计算腹腔肥大细胞脱颗粒率。结果:正常对照组、OVA变应性鼻炎组、穴位敷贴组、激素对照组、磷酸盐缓冲液(Phosphate Buffer Saline,PBS)阴性对照组小鼠腹腔肥大细胞脱颗粒率分别为(15±6)%、(53±11)%、(37±13)%、(31±15)%、(47±14)%。OVA变应性鼻炎小鼠的腹腔肥大细胞有明显的脱颗粒现象:与OVA变应性鼻炎小鼠相比,穴位敷贴组及激素对照组小鼠的腹腔肥大细胞脱颗粒现象显著减轻;PBS对照组小鼠的腹腔肥大细胞脱颗粒现象没有明显变化。结论:推测穴位敷贴抗过敏机制为稳定肥大细胞膜,抑制肥大细胞脱颗粒,减少致炎介质产生。 相似文献
995.
用梅花针叩刺斑秃区,后用艾条在患处温灸,治疗斑秃患者53例,并以口服薄芝片为对照治疗54例.3个疗程后前者总有效率为96.2%,后者为70.4%,两组疗效差异有统计意义. 相似文献
996.
目的:观察推拿在全髋关节置换术后康复治疗中的临床疗效。方法:将60例患者随机分成治疗组和对照组。治疗组30例进行推拿结合康复治疗,对照组30例进行单纯康复治疗。两组均治疗2星期。分别观察两组患者术后7天、术后2星期、术后6星期的改良人工髋关节Harris量表及汉密尔顿焦虑量表(Hamilton Anxiety Rating Scale,HAMA)。结果:Harris量表评分总分,两组组内患者不同时间点多重比较差异有统计学意义(P〈0.05);术后1天、术后7天及术后6星期两组间比较,差畀均无统计学意义(A,0.05);术后2星期两组间比较差异有统计学意义(P〈0.05)。HAMA量表两组组内患者不同时间点多重比较差异有统计学意义(P〈0.05);术后1天两纽间评分无显著性差异(P〉0.05);术后7天、术后2星期、术后6星期两组间评分均有显著性差异(P〈0.05)。结论:单位时间内,推拿结合康复治疗对全髋关节置换术后患者的疼痛、关节活动范围及焦虑等方面的改善作用优于单纯康复治疗。 相似文献
997.
傅鸿亮 《针灸推拿医学(英文版)》2004,2(3):47-50
先应用改良斜扳法和旋转定位扳法对腰椎间盘突出症患者进行手法复位,然后取水沟和委中为主穴,进行针剌治疗.共治疗97例患者,治愈58例,好转35例,无效4例,总有效率95.9%. 相似文献
998.
Objective
To investigate the influence of moxibustion products on mitochondrial transmembrane potential (MTP) and mRNA expression of Bax/Bcl-2 in alveolar type II epithelial A549 cells, and to further explore influence of moxibustion products on the oxidative damage of A549 cells.Methods
Smoke and particles generated by moxibustion were collected using the filter box for gas sampling. The moxa smoke extract (MSE) was diluted sequentially to the final concentrations of 0.05 mg/mL, 0.1 mg/mL, 0.2 mg/mL, 0.3 mg/mL and 0.4 mg/mL using the cell culture medium, and A549 cells were then intervened by the above MSE solution. Cell MTP was detected by JC-1 staining. Fluorescence quantitative polymerase chain reaction (PCR) was used to detect Bax/Bcl-2 mRNA expression of A549 cells.Results
Compared with cells in the normal control group, MTP was significantly decreased in cells of 0.3 mg/mL and 0.4 mg/mL MSE intervention groups (P<0.01); while MTP showed no significant changes in cells of 0.05 mg/mL, 0.1 mg/mL and 0.2 mg/mL MSE intervention groups (P>0.05); compared with cells in 0.05 mg/mL MSE intervention group, MTP was decreased significantly in cells of 0.1 mg/mL, 0.2 mg/mL, 0.3 mg/mL and 0.4 mg/mL MSE intervention groups (P<0.05 ); compared with cells in 0.1 mg/mL MSE intervention group, MTP was decreased significantly in cells of 0.4 mg/mL MSE intervention group (P<0.01). Bax mRNA expression of cells in each concentration of MSE intervention group all showed no significant difference compared to that in the normal control group; Bcl-2 mRNA expression of cells was reduced with the increase of MSE intervention concentration. Wherein, Bcl-2 mRNA expressions of cells in 0.4 mg/mL and 0.3 mg/mL MSE intervention groups were significantly reduced compared with that of cells in the normal control group (P<0.05); Bcl-2 mRNA expression of cells in 0.4 mg/mL MSE intervention group was significantly reduced compared to that in 0.05 mg/mL MSE intervention group (P<0.05).Conclusion
Certain higher concentration of moxa smoke could reduce MTP and mRNA expression of the anti-apoptosis gene Bcl-2 in alveolar type II epithelial A549 cells. Oxidative damage may be the important mechanism of apoptosis caused by the high concentration of moxa smoke solution, and further studies are necessary on the specific mechanisms.999.
Objective
To observe the clinical effects of tuina plus Western medication for functional dyspepsia (FD) due to liver qi stagnation and spleen deficiency.Methods
total of 72 patients in conformity with the inclusion criteria of FD were randomly divided into an observation group and a control group based upon the random number table, 36 cases in each group. The control group was treated with mosapride citrate dispersible tablets, and the observation group was treated with the same tablets plus tuina. Before the treatment and 4 weeks after the treatment, the clinical symptoms, quality of life (QOL) and depression severity were observed by the scale, and were followed up two months later after the treatment for assessment of the clinical effects.Results
After the treatment and at the follow-up, the symptom scores of FD and the sores of Hamilton depression rating scale (HAMD) in both groups decreased, and the scores in Chinese version of quality of life questionnaire for functional digestive disorders (Chin-FDDQL) increased, with statistically significant differences in comparison with the same group before the treatment (all P<0.05). In comparison between the two groups at the same time point after the treatment, the scores of FD symptoms, HAMD and Chin-FDDQL were improved better in the observation group than those in the control group, with statistically significant differences (all P<0.05). The total effective rates at the follow-up were 91.7% in the observation group and 75.0% in the control group, without statistical difference between the two groups (P>0.05). The rate of clinical cure and remarkable effect was 66.7% in the observation group, higher than 41.7% in the control group, it is higher in the observation group than that in the control group, with a statistically significant difference between the two groups (P<0.05).Conclusion
Tuina plus Western medication is precise in the therapeutic effects for FD due to liver qi stagnation and spleen deficiency and can effectively relieve clinical symptoms, elevate the QOL and alleviate depression severity of the patients. Moreover, it’s better than the treatment by Western medication alone in the long-term therapeutic effects.1000.
Do Thi Ha Quan Cheng Chen Tran Manh Hung Ui Joung Youn Tran Minh Ngoc Phuong Thien Thuong Hong Jin Kim Yeon Hee Seong Byung Sun Min KiHwan Bae 《Archives of pharmacal research》2009,32(2):177-183
Chromatographic separation of the EtOAc fraction from the leaf and stem of Vitis amurensis led to the isolation of six oligostilbenoids (i.e., r-2-viniferin (1), trans-amurensin B (2), trans-ɛ-viniferin (3), gnetin H (4), amurensin G (5), (+)-ampelopsin A (8)) and four stilbenoids (i.e., trans-resveratrol (6), (+)-ampelopsin F (7), piceatannol (9), and trans-piceid (10)). The structures have been identified on the basis of spectroscopic evidence and physicochemical properties. The isolates
were investigated for cytotoxic activity against three cancer cell lines in vitro using the MTT assay method. Amurensin G (5) and trans-resveratrol (6) showed significant cytotoxic activity against L1210, K562 and HTC116 cancer cell lines with IC50 values ranging from 15.7 ± 2.1 to 30.9 ± 1.8 μM. (+)-Ampelopsin A (8) and trans-piceid (10) exhibited considerable cytotoxic activity against L1210 (IC50 values of 30.6 ± 4.1 and 28.7 ± 2.81 μM, respectively) and K562 (IC50 values of 38.6 ± 0.82 and 24.6 ± 0.76 μM, respectively). Gnetin H (4) showed only weak cytotoxic activity against L1210 with an IC50 value of 40.1 ± 4.23 μM. On the other hand, r-2-viniverin (1), trans-amurensin B (2), trans-ɛ-viniferin (3), (+)-ampelopsin F (7), and piceatannol (9) exhibited no activity on three cancer cell lines. 相似文献