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991.
3 124例各类斜视手术的分布调查 总被引:4,自引:2,他引:2
目的:了解临床各类斜视手术的分布情况,以掌握最常见斜视手术分布数据。方法:3年3124例斜视手术资料的统计分析。结果:共同性斜视的手术2629例占84.2%。麻痹性斜视的手术495例占15.8%。共同性外科视的手术1779例占67.7%。先天性麻痹性斜视手术中先天性上斜肌麻痹手术量占第一位。后天性麻痹性斜视手术中外直肌麻痹手术量占第一位。结论:最常见的斜视手术是共同性斜视。共同性外斜视的手术量最大 相似文献
992.
新型弹性襻前房型人工晶体植入术临床分析 总被引:2,自引:0,他引:2
为探讨新型弹性襻前房型人工晶体植入的效果,观察了23例24只眼。其中老年性白内障18眼,外伤性白内障6眼。其中包括13眼行二期植入术。病例随访时间2个月至2年。结果:24只眼中,17眼(70.83%)视力恢复至4.5或4.5以上,5眼(20.83%)恢复至5.0或5.0以上。结论:新型弹性襻前房型人工晶体植入术操作简单,安全、有效 相似文献
993.
Antioxidants attenuate noncholinergic airway constriction. To further investigate the relationship between tachykinin-mediated airway constriction and oxygen radicals, we explored citric acid-induced bronchial constriction in 48 young Hartley strain guinea-pigs, divided into six groups: control; citric acid; hexa(sulphobutyl)fullerenes + citric acid; hexa(sulphobutyl)fullerenes + phosphoramidon + citric acid; dimethylthiourea (DMTU) + citric acid; and DMTU + phosphoramidon + citric acid. Hexa(sulphobutyl)fullerenes and DMTU are scavengers of oxygen radicals while phosphoramidon is an inhibitor of the major degradation enzyme for tachykinins. Animals were anaesthetized, paralyzed, and artificially ventilated. Each animal was given 50 breaths of 4 ml saline or citric acid aerosol. We measured dynamic respiratory compliance (Crs), forced expiratory volume in 0.1 (FEV0.1), and maximal expiratory flow at 30% total lung capacity (Vmax30) to evaluate the degree of airway constriction. Citric acid, but not saline, aerosol inhalation caused marked decreases in Crs, FEV0.1 and Vmax30, indicating marked airway constriction. This constriction was significantly attenuated by either hexa(sulphobutyl)fullerenes or by DMTU. In addition, phosphoramidon significantly reversed the attenuating action of hexa(sulphobutyl)fullerenes, but not that of DMTU. Citric acid aerosol inhalation caused increases in both lucigenin- and t-butyl hydroperoxide-initiated chemiluminescence counts, indicating citric acid-induced increase in oxygen radicals and decrease in antioxidants in bronchoalveolar lavage fluid. These alterations were significantly suppressed by either hexa(sulphobutyl)fullerenes or DMTU. An elastase inhibitor eglin-c also significantly attenuated citric acid-induced airway constriction, indicating the contributing role of elastase in this type of constriction. We conclude that both oxygen radicals and elastase play an important role in tachykinin-mediated, citric acid-induced airway constriction. 相似文献
994.
995.
The effect of pregnenolone 16alpha-carbonitrile on the pharmacokinetics and metabolism of dapsone in rats. 总被引:1,自引:0,他引:1
M Lu S M Poloyac P J McNamara R A Blouin 《The Journal of pharmacy and pharmacology》1999,51(7):803-810
The purpose of this study was to evaluate the effect of pregnenolone 16 alpha-carbonitrile (PCN) on the interconversion pharmacokinetics and metabolism of dapsone. To determine microsomal CYP3A activity and protein, eight rats (4 PCN, 4 corn oil) received a 1 mg kg(-1) intravenous bolus dose of dapsone, followed by blood and urine sampling. The formation clearance of dapsone hydroxylamine (CLf DDS-NOH) was calculated from the obtained samples. Interconversion pharmacokinetics estimates were obtained after 10 rats (5 PCN, 5 control) received 1 mg kg(-1) dapsone or 1.17 mg kg(-1) monoacetyldapsone, with a 24-h wash-out. Results from the interconversion analysis demonstrated that PCN significantly increased systemic clearance (CLs) of dapsone, but not its interconversion. The in-vivo/in-vitro correlation study demonstrated that PCN significantly increased CLs of dapsone (8.55 to 16.39mLmin(-1); P<0.01) and CLf DDS-NOH (0.13 to 0.18mLmin(-1); P<0.01). PCN treatment produced a 69% increase in CYP3A protein, and increased 6beta- and 2beta-hydroxytestosterone formation rates. Significant correlations were found between CLf DDS-NOH and either 6beta- (r2 = 0.925), 2beta-hydroxytestosterone (r2 = 0.92), or CYP3A1/2 protein (r2= 0.60). We conclude that PCN treatment produces significant increases in CLs (dapsone) and CLf (DDS-NOH) in rats. These changes were not due to changes in the reversible metabolism of dapsone. These results suggest that the formation clearance of dapsone hydroxylamine reflects alterations in CYP3A activity, despite the fact that it accounted for a small part of the systemic clearance of dapsone. 相似文献
996.
中国汉族人不同年龄和性别载脂蛋白E等位基因频率的群体分布 总被引:4,自引:0,他引:4
目的 研究在上海地区健康汉族人中不同年龄和性别的载脂蛋白E基因频率的群体分布,方法 本次调查包括649名健康汉族人(女:237人,男:412人)载脂蛋白E基因组PCR扩增,前引物:5′-GGC,ACGGCTGTCGAAGGAGCT-3′;后引物:5′-GAT GGG GCT GAG GCC GCG CT-3′,PCR产物用5单位限制性内切酶Cf0I酶切,用20%聚丙烯酰胺凝胶电泳分离。结果:Apo 相似文献
997.
影响重症急性胰腺炎预后的主要因素 总被引:1,自引:0,他引:1
目的 :探索重症急性胰腺炎分度和治疗方案对预后的影响。方法 :回顾性分析 1983年— 1998年间176例重症急性胰腺炎患者临床资料 ,根据胰腺出血坏死程度、腹水量及胰外受侵范围 ,将重症急性胰腺炎分为 4度 ,分析各度治愈率和采用不同方案的治疗效果。结果 : 度治愈率为 10 0 % , 度 69.3 % , 度 5 3 .1% , 度2 7.3 %。除 度、 度间差异不明显 ( P>0 .0 5 )外 ,其余各度之间均有明显差异 ( P<0 .0 5 )。 度中切除术组疗效明显差 ( P<0 .0 5 )。结论 :影响预后的主要因素 :1胰腺坏死程度 ,坏死越重 ,预后越差。 2治疗方法的选择 ,治愈率以切除组最差 ( 2 8.6% ) ,清除术组 68.4 % ,非手术组 82 .4 % ,因而 ,保守治疗列为首选治疗方案 相似文献
998.
RP—HPLC测定清眩丸中欧前胡素的含量 总被引:6,自引:0,他引:6
目的:建立反相高效液相色谱测定清眩丸中欧前胡素含量的方法。方法:采用乙醇做溶剂,水浴加热回流提取。LUNA-C18色谱柱分离测定,流动相为乙腈-水(53∶47),流速1mL·min-1,检测波长300nm。结果:欧前胡素与其相邻峰的分离度是15,理论板数按欧前胡素峰计算是16155,欧前胡素对照品线性范围是1462~4875μg·mL-1,加样平均回收率980%。结论:用本文方法测定清眩丸中欧前胡素的含量,操作简便,结果准确。 相似文献
999.
Sheng-Ting Li Xiu-Jie Liu Zong-Liang Lu Rong-Fang Shi Xiao-Dong Zhu Wen-Qi Chen Qing-Wen Wu Yun-Zhong Liu 《Journal of nuclear cardiology》1996,3(6):457-463
Background
Assessment of viable myocardium in territories of hypoperfused myocardium is important for predicting functional recovery after revascularization. This study was designed to evaluate quantitative analysis of 99mTc-labeled 2-methoxyisobutyl isonitrile (MIBI) myocardial perfusion imaging combined with isosorbide dinitrate (ISDN) infusion to detect myocardial viability in patients with chronic coronary artery disease before and after revascularization.Methods and Results
Twenty-seven consecutive patients with previous myocardial infarction and left ventricular dysfunction (left ventricular ejection fraction 35.2%±13.5%) referred for coronary artery bypass (CABG) were studied with 99mTc-labeled MIBI single-photon emission computed tomograpy at rest and during ISDN infusion before CABG followed by resting imaging after CABG. Quantitative analysis was performed with circumferential profiles. Left ventricular function (global and regional) was assessed by radionuclide ventriculography before and after CABG. Out of 212 abnormal perfusion segments with resting 99mTc-labeled MIBI SPECT, 99 segments (47%) showed improved uptake of 99mTc-labeled MIBI during ISDN infusion. The mean ratio of myocardial uptake was 0.58±0.25 (resting 0.53±0.23; p<0.05). After CABG, of 212 segments with hypoperfusion, 108 segments (51%; p>0.05 vs ISDN) showed improved uptake of 99mTc-labeled MIBI. The mean ratio of myocardial uptake was 0.60±0.26 (resting 0.53±0.23; p<0.05). The concordance between the improvement of post-CABG wall motion and that of pre-CABG ISDN perfusion imaging was 83%, between the improvement of wall motion and perfusion imaging after CABG 94%, and between the improvement of pre-CABG ISDN and post-CABG perfusion imaging 83%, respectively.Conclusion
ISDN infusion can improve the uptake of 99mTc-labeled MIBI in hypoperfused myocardium and increase the efficiency of 99mTc-labeled MIBI in the detection of viable myocardium in patients with previous myocardial infarction and left ventricular dysfunction. 相似文献1000.
猪精液抑制素的制备及其放射免疫分析 总被引:5,自引:0,他引:5
本文报道以猪精液为原料制备的抑制素的生物活性、氨基酸组成、分子量以及抑制素的放射免疫分析。新鲜猪精液经乙醇沉淀、丙酮清洗和Sephadex G-100凝胶过滤,获得抑制素活性组分UⅡ。生物测定表明:所得抑制素单位重量的生物活性稍高于Chari氏牛精液抑制素纯品的活性;UⅡ含17种氨基酸,分子量为18,500道尔顿,用UⅡ免疫家兔,获得亲和为强(Ka=6.58×10~(10)L/M)、效价高的特异抗血清,终稀释度可达1:100,000;用双抗体法进行猪精液抑制素放射免疫分析,检测灵敏度为87.5微微克,经Logit转换,标准曲线的直线化较好。按Cerceo效点法综合评价,积分值达28,表明此法较优。 相似文献