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121.
122.
对耳轮过度前突为对耳轮的角度过锐,致使耳轮的位置相应后移,表现为与招风耳完全相反的畸形。畸形虽不十分明显,但影响美观。自1992年4月开始应用患侧耳廓软骨和耳后皮瓣对5例患者8只外耳进行治疗得到满意效果。认为文中所述方法是矫正对耳轮过度前突畸形的良好方法。 相似文献
123.
Effects of blood coagulation factor XIII on the development of experimental cerebral aneurysms in rats 总被引:1,自引:0,他引:1
Pathological and experimental studies have shown that cerebral aneurysms develop in part as a result of injury to the blood vessel wall. One of the peculiar aspects of aneurysm development is a defective proliferative or healing response to such injury. To examine this phenomenon, blood coagulation Factor XIII, which is known to enhance the healing process of wounds in general, was given to rats to induce experimental cerebral aneurysms. The rats were subjected to ligation of one common carotid artery and induction of hypertension, and were fed beta-aminoproprionitrile. Two weeks thereafter, Factor XIII was injected intravenously daily for 5 days (10 U/100 gm body weight/day). Twelve days after the start of Factor XIII injections, the rats were sacrificed and examined under light and electron microscopy. In seven of 12 bifurcations which developed small aneurysms, prominent intimal thickening was observed in the aneurysm lumen. In the most advanced cases, the aneurysm lumen was completely filled with proliferated smooth-muscle cells and collagen. In five of nine bifurcations that showed no aneurysm development, apparent intimal thickening was found at the site where aneurysms might be expected to grow. In the group of rats studied for induction of cerebral aneurysms but not given Factor XIII, none of 11 bifurcations with or without aneurysms showed such intimal thickening. The results indicated that the proliferative response at the sites of aneurysm development was modified by exogenous Factor XIII. 相似文献
124.
在实验设计时应保证一定的检验效能;当统计检验结果是阴性时,应估计其检验效能。本文探讨了完全随机设计的方差分析中检验效能的估计方法。结果表明,检验效能与样本含量的大小及样本均数间的差别有关。同时,用医学实例说明其应用。 相似文献
125.
The susceptibilities of Nagase analbuminemic rats (NAR) and control Sprague-Dawley rats (SDR) to N-ethyl-N-nitrosourea (ENU) were compared. In Experiment I, the rats were given daily subcutaneous injections of 10 mg/kg of ENU for a week from 4 weeks of age. In Experiment II, mother rats were given a single subcutaneous injection of 60 mg/kg of ENU on day 17 of pregnancy and tumor development in their offspring was examined. In Experiment I, the incidence of neurogenic tumors was slightly, but not significantly, higher in NAR than in control rats. In Experiment II, the incidence of total tumors including neurogenic tumors was significantly higher in NAR (40/43, 93.0%) than in SDR (13/61, 21.3%). NAR showed particularly high susceptibility to induction of neurogenic tumors (34/43, 79.1%) and renal tumors (15/43, 34.9%). In an attempt to elucidate the underlying mechanisms of the increased susceptibility of NAR to ENU, O6-ethylguanine, a major premutagenic ethylated DNA adduct, was quantitated in fetal brain DNA of NAR and SDR after a pulse exposure to 60 mg/kg ENU. No significant difference in the initial formation or subsequent repair of O6-ethylguanine was observed in the two strains, indicating that abnormality at some later stage(s) of chemical carcinogenesis may lead to the increased susceptibility of NAR to induction of neurogenic tumors. 相似文献
126.
Ezer Kang Bruce D. Rapkin Carolyn Springer Jen Haejin Kim 《Journal of immigrant and minority health / Center for Minority Public Health》2003,5(2):49-58
Access to and utilization of care for HIV-positive Asians (A) and Pacific Islanders (PI) have been largely unaddressed despite the rising influx of immigrants from Asia and the Pacific to the United States and the growing HIV prevalence in these regions. This paper describes the cultural attitudes, behaviors, and perceptions that affect access to and utilization of care among Asian undocumented noncitizens living with HIV/AIDS (UNWHA) in New York City. Sixteen semistructured interviews with HIV-positive UNWHAs revealed that their access to care was influenced by community misperceptions of HIV transmission, discriminatory attitudes towards persons living with HIV, competing immigration related stressors, and difficulty navigating service systems. These findings underscore the importance of integrating HIV treatment with primary prevention and awareness of immigration-related stressors to ensure timely access to screening services and care among Asian UNWHAs. 相似文献
127.
Hemochromatosis is characterized by pathologic iron overload which often leads to various pathological conditions. The mechanism by which excess iron induces these conditions is not clearly understood. Using rats as the model, this investigation was conducted to explore the mechanism of toxicity associated with iron overload. Sprague-Dawley male rats were fed a 3% carbonyl iron-supplemented diet for eight weeks to achieve iron accumulation. Liver iron reached approximately 2 mg/g which is more than 16 times the control values (mean +/- SD, 0.12 +/- 0.02 mg/g, p < 0.001). Serum iron was consistently higher in the experimental rats (mg/L): 3.41 +/- 0.58 versus 1.89 +/- 0.18, p < 0.001. The high levels of iron accompanied enhanced oxidative damage in the hepatic nuclear DNA when 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured as a product of DNA oxidation. The levels of 8-OHdG in the experimental samples were significantly higher than the controls (8-OHdG X 10(-5)/dG): 4.22 +/- 1.82 versus 1.84 +/- 0.33, p < 0.05. The results of serum enzyme assays suggest that iron overload caused mild hepatocellular damage: alanine transaminase significantly increased; lactate dehydrogenase did not change; alkaline phosphatase decreased. Since the accumulation of 8-OHdG in the nuclear DNA is highly deleterious to cells, these data suggest oxidative damage in the nuclear DNA may be a critical factor in inducing diseases associated with iron overload. 相似文献
128.
从加强医疗病房的重危患餐巾选取因呼吸衰竭而给予呼吸机支持的患者40例,随机分为A组20例进行肠外营养(parenteral nutrition,PN)治疗,B组20例未行PN治疗。对通气/换气功能各指标进行分析,结果两组患者的呼吸频率、pH、PaO_2、PaCO_2及HCO_3~-无明显差异;A组氧分压与吸入气氧浓度比值轻度降低,而肺泡-动脉氧压差及肺内分流明显升高。提示PN中的脂肪乳和高糖可能是导致呼吸功能改变的重要因素。 相似文献
129.
我国丙型和戊型肝炎人群流行病学调查及流行因素的研究 总被引:55,自引:1,他引:54
为阐明丙型和戊型肝炎在我国的流行严重度和流行规律,采用描述流行病学、血清流行病学和分子流行病学相结合的研究方法,对两型肝炎的流行特征和流行因素进行了研究。结果发现;一般人群调查近9万人丙型肝炎和戊型肝炎的流行率各为2.2%和9.7%,散 生病毒性肝炎感染比率各为2.15%和16.4%。丙型肝炎在我国主要经血传播,与血液接触密切人群中HCV感染率高达50-70%,慢性化比比例高达40-60%,目前供 相似文献
130.