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991.
海洛因对大鼠黄嘌呤氧化酶和血尿酸的影响   总被引:1,自引:0,他引:1  
目的:检测黄嘌呤氧化酶(xanthineoxidase ,XOD)和血浆尿酸含量,研究海洛因给药对嘌呤核苷酸分解代谢的影响。方法:建立海洛因给药、停药大鼠模型,测定尿酸及XOD含量。结果:给药组尿酸及XOD含量高于对照组。与给药组比较,两个停药组尿酸含量、血浆和肝XOD含量降低;停药8d组脑顶叶XOD含量降低,脑干XOD含量略有下降趋势。但两个停药组脑干XOD含量仍高于对照组。结论:海洛因通过增加XOD的含量,使嘌呤核苷酸分解代谢增强,且脑中这一作用消除较慢。  相似文献   
992.
高效液相色谱法测定清肺抑火片中黄芩苷的含量   总被引:1,自引:0,他引:1  
马春云 《中国药业》2005,14(4):37-38
目的:探讨清肺抑火片的含量测定方法.方法:采用高效液相色谱法(HPLC法)测定清肺抑火片黄芩中黄芩苷的含量.色谱柱为Elite 0DS C18柱(250 mm×4.0 mm,5μm),流动相为甲醇-水-磷酸(45:55:0.2),流速为1 mL/min,检测波长为315 nm.结果:回归方程为Y=85.915 4 2 701.674 3X,r=0.999 3,平均回收率为97.93%,RSD为1.76%(n=6).结论:HPLC法简便、快速、可靠,可用于清肺抑火片的质量控制.  相似文献   
993.
Studies have shown that exposure to diesel exhaust particles (DEP) suppresses pulmonary host defense against bacterial infection. The present study was carried out to characterize whether DEP exposure exerts a sustained effect in which inhaled DEP increase the susceptibility of the lung to bacterial infection occurring at a later time. Brown Norway rats were exposed to filtered air or DEP by inhalation at a dose of 21.2 +/- 2.3 mg/m3, 4 h/day for 5 days, and intratracheally instilled with saline or 100,000 Listeria monocytogenes (Listeria) 7 days after the final DEP exposure. Bacterial growth and cellular responses to DEP and Listeria exposures were examined at 3 and 7 days post-infection. The results showed that inhaled DEP prolonged the growth of bacteria, administered 7 days post DEP exposure, in the lung as compared to the air-exposed controls. Pulmonary responses to Listeria infection were characterized by increased production of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, IL-12, and IL-10 by alveolar macrophages (AM) and increased presence of T lymphocytes and their CD4+ and CD8+ subsets in lung draining lymph nodes that secreted elevated levels of IL-2, IL-6, IL-10, and interferon (IFN)-gamma. Diesel exhaust particles were found to inhibit Listeria-induced production of IL-1beta and TNF-alpha, which are responsible for the innate immunity, and IL-12, which initiates the development of T helper (Th)1 responses, but enhance Listeria-induced AM production of IL-10, which prolongs Listeria survival in these phagocytes. The dual action of DEP on AM production of IL-12 and IL-10 correlated with an inhibition of the development of bacteria-specific T lymphocytes by DEP. Cytokine production by lymphocytes from DEP- and Listeria-exposed rats showed a marked decrease in the production of IL-2, IL-10, and IFN-gamma compared to Listeria infection alone, suggesting either that DEP inhibit the production of cytokines by lymphocytes or that these lymphocytes contained T-cell subsets that are different from those of Listeria infection alone and less effective in mediating Th1 immune responses. This study demonstrates that inhaled DEP, after a 7-day resting period, increase the susceptibility of the lung to bacterial infection occurring at a later time by inhibiting macrophage immune function and suppressing the development of T-cell-mediated immune responses. The results support the epidemiological observations that exposure to DEP may be responsible for the pulmonary health effects on humans.  相似文献   
994.
Exposure to diesel exhaust particles (DEP) during the sensitization process has been shown to increase antigen-specific IgE production and aggravate allergic airway inflammation in human and animal models. In this study, we evaluated the effect of short-term DEP exposure on ovalbumin (OVA)-mediated responses using a post-sensitization model. Brown Norway rats were first exposed to filtered air or DEP (20.6 +/- 2.7 mg/m3) for 4 h/day for five consecutive days. One day after the final air or DEP exposure (day 1), rats were sensitized with aerosolized OVA (40.5 +/- 6.3 mg/m3), and then again on days 8 and 15, challenged with OVA on day 29, and sacrificed on days 9 or 30, 24 h after the second OVA exposure or the final OVA challenge, respectively. Control animals received aerosolized saline instead of OVA. DEP were shown to elicit an adjuvant effect on the production of antigen-specific IgE and IgG on day 30. At both time points, no significant airway inflammatory responses and lung injury were found for DEP exposure alone. However, the OVA-induced inflammatory cell infiltration, acellular lactate dehydrogenase activity and albumin content in bronchoalveolar lavage (BAL) fluid, and numbers of T cells and their CD4+ and CD8+ subsets in lung-draining lymph nodes were markedly reduced by DEP on day 30 compared with the air-plus-OVA exposure group. The OVA-induced nitric oxide (NO) in the BAL fluid and production of NO, interleukin (IL)-10, and IL-12 by alveolar macrophages (AM) were also significantly lowered by DEP on day 30 as well as day 9. DEP or OVA alone decreased intracellular glutathione (GSH) in AM and lymphocytes on days 9 and 30. The combined DEP and OVA exposure resulted in further depletion of GSH in both cell types. These results show that short-term DEP exposure prior to sensitization had a delayed effect on enhancement of the sensitization in terms of allergen-specific IgE and IgG production, but caused an attenuation of the allergen-induced airway inflammatory responses.  相似文献   
995.
Diarylpyrazoles are a group of 1,5-diphenylpyrazole analogs of which several have been found to exhibit antagonist properties toward the cannabinoid receptors. SR141716A [N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide], the first reported antagonist, is a highly potent and selective CB1 receptor ligand that prevents or reverses CB1-mediated effects. Other analogs, such as AM251 [N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide] and AM281 [1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-4-morpholinyl-1H-pyrazole-3-carboxamide], have also shown high binding affinities to the central cannabinoid receptor and behave as antagonists/inverse agonists. There has been no report on the metabolism of any of the diarylpyrazoles, and it is unknown whether their metabolites retain any receptor binding properties. We report a study of the in vitro metabolisms of three diarylpyrazole analogs, SR141716A, AM251, and AM281, in rat liver microsomes. The metabolic profile was obtained using high-performance liquid chromatography with UV and mass spectrometry detectors. All identified metabolites are characterized by structural modifications on the terminal group of the 3-substituent. Thus, three pairs of isomeric metabolites were identified from the microsomal incubation of SR141716A; these metabolites are products of hydroxylation, hydroxylation followed by dehydration, and a combination of the two. For AM251, only four metabolic products were detected, with two resulting from monohydroxylation of the piperidine ring and the other two being products of dehydration of the first pair of metabolites. For AM281, in which the terminal group of the 3-substituent is a morpholine ring, dehydration of the first two metabolites yielded a single third metabolite due to only one possible position for the carbon-carbon double bond on the morpholinyl ring.  相似文献   
996.
为给临床治疗尺骨鹰嘴骨折选择方法提供依据.对分别采用非手术治疗(A组)、张力带钢丝内固定(B组)、双边外固定器固定(C组)三种方法治疗的112例该病患者的临床资料进行了回顾性分析.依据远期临床功能恢复情况分优、良、可、差4级标准进行疗效评价,结果优良率A组78.25%、B组92.30%、C组94.59%.B组和C组的优良率明显优于A组,B组和C组的优良率接近.认为治疗尺骨鹰嘴骨折张力带钢丝法为有效可靠的选择,双边外固定器固定效果满意,值得推广应用.  相似文献   
997.
灯盏花素在家犬与家兔体内的药代动力学研究   总被引:5,自引:0,他引:5  
目的:研究灯盏花素在家犬与家兔体内的药代动力学.方法:采用液-液萃取法制备血样供试品,HPLC法测定.结果:灯盏花素在家犬体内的过程符合双室模型,主要药动学参数为:A=56.93±23.14,B=1.61±1.11,α=0.2328±0.1321min-,β=0.0255±0.0187min-,T1/2α=2.98±1.42min,T1/2β=27.14±14.35min,K21=0.0312±0.0112min-,K10=0.1904±0.1319min-,K12=0.0367±0.0306min-1,CL=39.41±20.44ml·min-,AUC=3074±1055mg·min·L-;灯盏花素在家兔体内的过程符合双室模型,主要药动学参数为:A=2.64±1.12,B=0.28±0.12,α=0.1439±0.0681min-,β=0.0162±0.0456min-,t1/2α=4.82±1.65min,t1/2β=42.66±18.77min,K21=0.0285±0.0147min-,K10=0.0820±0.00378min-,K12=0.0496±0.0241min-,CL=337.05±156.48ml·min-1,AUC=356±114mg·min·L-1.结论:灯盏花素在家犬与家兔体内半衰期很短,其作用时间短,消除速度快.  相似文献   
998.
笔者用逍遥散治输卵管不通、经期延长、卵巢囊肿等疗效满意,现报道如下。  相似文献   
999.
笔者自拟宣痹通脉饮治疗冠心病80例,收到了满意的疗效,现报告如下.  相似文献   
1000.
苁蓉总苷对氢化可的松致肾阳虚小鼠学习记忆功能的影响   总被引:8,自引:0,他引:8  
目的:观察苁蓉总苷对氢化可的松所致肾阳虚模型小鼠学习记忆障碍的影响.方法:连续灌胃给予苁蓉总苷30d,于实验的第11~18天灌胃氢化可的松(正常对照组除外)复制肾阳虚模型,观察记录小鼠的一般状态及死亡情况,使用跳台法观察小鼠的学习记忆功能.结果:(1)苁蓉总苷各剂量组少动、竖毛、少食、少饮、颤抖等阳虚症状均有明显改善,动物死亡数明显减少.(2)苁蓉总苷各剂量组在给予氢化可的松后,各动物的跳台潜伏期明显延长,5min内的错误次数明显减少.结论:苁蓉总苷能明显改善氢化可的松致阳虚小鼠的一般状况及学习记忆功能障碍,并能明显降低小鼠的死亡率.  相似文献   
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