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71.
Epidural infiltration by leukemic cells in Acute Non Lymphoblastic Leukemia (ANLL), and extradural granulocytic sarcomas as a cause of spinal cord compression are extremely rare phenomena. Very few cases have been recorded in the literature. In this brief case report we describe a young patient with acute myeloblastic leukemia (M4, FAB) who presented with sudden spinal cord compression during relapse after bone marrow transplantation. The literature on this subject is also reviewed. 相似文献
72.
氯丙醇对大鼠的毒性研究 总被引:3,自引:0,他引:3
进行氯丙醇对大鼠毒作用研究 ,并进行氯丙醇暴露对健康影响评价的生物效应标志物探讨 ,为进行人群氯丙醇暴露对健康的影响评价提供科学依据。选用健康雄性断乳SD大鼠 1 76只 ,随机分为 8组 ,经口灌胃给予 0、0 2 5、0 5、1 0、2 0、4 0、8 0、1 6 0mg kg的 3 氯 1 ,2 丙二醇 (3 MCDP) 90天 ,进行体重、食物利用率、血液学指标、血生化指标、尿液中N 乙酰 β D 氨基葡萄糖苷酶 (NAG)、γ 谷胺酰转肽酶 (GGT)和总蛋白、精子数目、精子存活率和畸形率、睾丸组织中乳酸脱氢酶 (LDH)和乳酸脱氢酶同工酶 X(LDH X)、脏体比及其病理组织学测定和分析。结果表明 ,不同暴露剂量的氯丙醇对动物体重、食物利用率、血红蛋白、红细胞、白细胞、血丙氨酸氨基转移酶 (AST)、天冬氨酸氨基转移酶 (ALT)、肌酐、尿素氮、血清碱性磷酸酶 (ALP)、乳酸脱氢酶 (LDH)、总蛋白、白蛋白、尿GGT酶和总蛋白及睾丸LDH酶均未见显著影响。在 4 0、8 0和 1 6 0mg kg剂量组 ,动物尿N 乙酰 β D 氨基葡萄糖苷酶 (NAG)活性显著增加 ,肾体比增大 ,并出现肾毒性病理改变 ,精子数目也降低。在 8 0和 1 6 0mg kg剂量组 ,精子存活率和睾丸LDH X显著降低 ,睾丸和附睾出现病理改变 ,3 MCDP无致精子畸变作用。由此可见尿液中NAG酶活性和精子 相似文献
73.
移植肾彩色多普勒血流超声与肾穿刺活检的对照研究 总被引:2,自引:0,他引:2
将彩色多普勒血流超声与移植肾活检结果相对照。评价无创性CDFI对移植肾排异反应的诊断价值。结果:不同病理状态下移植肾的阻力指数有所不同。急性排异和慢性排异反应组的RI值明显高于正常组。两次肾活检提示由急性排异转为慢性排异反应的同一患者,CDFI的动态观察显示,RI值明显增高。 相似文献
74.
Acute toxicity of two pyrethroids,permethrin, and cypermethrin in neonatal and adult rats 总被引:2,自引:0,他引:2
Franco Cantalamessa 《Archives of toxicology》1993,67(7):510-513
The present study aims specifically at obtaining a comparison of the acute toxicity of cypermethrin (CY), a type I pyrethroid, and permethrin (PERM), a type II pyrethroid, administered orally as a single dose to neonatal and adult rats, and at assessing the importance of pyrethroid biotransformation in CY and PERM toxicity through use of drug metabolism inhibitors. Our experiments show that CY is more toxic than PERM to adult and neonatal rats. The sensitivity of neonatal rats both to CY and to PERM toxicity is higher, the younger the animals. CY is much more toxic than PERM in the neonatal rat, compared with the adult. In rats aged 8, 16, and 21 days, pretreatment with piperonil butoxide (PB), a monooxygenase inhibitor, or with tri-o-tolyl phosphate (TOTP), an esterase inhibitor, does not produce significant variations in the lethal effects of CY and PERM. Instead, in the adult rats, a significant increase in CY (X2=5.97;p<0.05) and PERM (X2=4.37;p<0.05) mortality occurred in rats pretreated with esterase inhibitors, whereas no increase in CY and PERM toxicity was found in adult animals pretreated with monooxygenase inhibitor. It was concluded that the higher level of sensitivity of the neonate rat to pyrethroid toxicity is probably due to incomplete development of the enzymes which catalyze the metabolism of pyrethroids in the liver of young animals. It is suggested that ester hydrolysis is an important pyrethroids detoxification reaction in the adult rat. 相似文献
75.
POSITIVE INTERACTION OF ETHANOL AND KAVA RESIN IN MICE 总被引:3,自引:0,他引:3
D. D. Jamieson P. H. Duffield 《Clinical and experimental pharmacology & physiology》1990,17(7):509-514
1. The lipid soluble extract of the psychoactive beverage kava has hypnosedative properties which can be measured by the length of time that the righting reflex is lost. 2. Ethanol and the lipid soluble extract (kava resin) have been shown greatly to increase each others hypnotic action in mice. Ethanol also increases the toxicity of kava markedly. 3. This interaction of kava and alcohol has important clinical and social consequences since, in contrast to traditional usage, kava is now often taken in conjunction with alcoholic drinks. 相似文献
76.
Rebecca J Sommer Adam J Hume Jessica M Ciak John J Vannostrand Megan Friggens Mary K Walker 《Toxicological sciences》2005,83(2):363-371
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes cardiovascular toxicity in laboratory animals, including alteration in several processes in which beta-adrenergic receptor (beta-AR) signaling plays important roles. Thus, our laboratory investigated the effects of TCDD on beta-AR expression and signal transduction. Fertile chicken eggs were injected with vehicle (corn oil), 0.24 or 0.3 pmol TCDD/g egg on incubation day 0 (D0) or D5. On D10, heart function was assessed by ECG in ovo. Exposure to TCDD increased the incidence of arrhythmias and decreased the positive chronotropic responsiveness of the heart to isoproterenol. The reduced beta-AR responsiveness was, in part, independent of any overt morphological changes in the heart as chick embryos exposed to TCDD on D5 displayed an intermediate responsiveness to beta-AR agonist in the absence of the dilated cardiomyopathy observed in chick embryos exposed to TCDD on D0. TCDD did not decrease the chronotropic response of the heart to agents that stimulate signals downstream of the beta-AR. In fact, TCDD-exposed embryos were more sensitive than controls to forskolin, increasing heart rates (HR) 21.8 +/- 3.5 beats per min (bpm) above baseline versus control values at 6.3 +/- 2.7 bpm above baseline. TCDD exposure also augmented the negative chronotropic response of the heart to verapamil, decreasing HR -23.2 +/- 7.4 bpm relative to baseline versus control embryos at -12.7 +/- 5.9 bpm below baseline. Finally, the mean cardiac beta1-AR mRNA expression in D10 embryos was not significantly altered by exposure to TCDD on D0. These findings establish that a functional end point of the developing chick heart is sensitive to TCDD exposure and that the TCDD-induced reduction in beta-AR responsiveness may result from alterations in signal transduction upstream of adenylyl cyclase. 相似文献
77.
The delayed cytotoxicity of the Multicentre Evaluation of In vitro Cytotoxicity (MEIC) reference chemicals was investigated in rat hepatoma-derived Fa32 cells. The cells were treated for 24 h with the test chemicals, and were than further cultured for 5 days in normal culture medium. The cytotoxicity was measured by the neutral red uptake inhibition, and the results were quantified by determining the NI50del. This is the concentration of test compound required to decrease the neutral red uptake with 50% compared with control cells. The results were compared with the acute NI50, the corresponding value measured immediately after 24 h treatment of the cells. On a total of 44 chemicals, nine showed delayed cytotoxicity (NI50del lower than or equal to NI50), 11 a probably delayed, and 24 no delayed cytotoxicity (NI50del more than 1.5×NI50). When the NI50del was compared with human toxicity, a correlation coefficient r2=0.761 was obtained. For the same series of 44 chemicals this correlation was clearly higher than that for human hepatoma-derived Hep G2 cells (r2=0.695). The Hep G2 assay was the best acute in vitro assay for the prediction of human toxicity within the MEIC study. Consequently, the delayed cytotoxicity assay on cultured Fa32 cells has the best prediction value so far obtained for the human toxicity. 相似文献
78.
几种中草药复配杀虫剂的急性毒性实验研究 总被引:1,自引:1,他引:0
为有效开发植物杀虫剂资源及今后的推广应用提供科学依据。用两种粉剂和两种醇剂的杀虫应用浓度给小白鼠灌,而家兔则行皮肤刺激试验。结果显示,除醒剂Y-13经口有中毒情况发生外,其它3种制剂均无中毒现象,醇剂Y-13的家兔皮肤也无刺激反应发生。作者认为:4种制剂在有杀虫效果的前提下,杀虫应用浓度对人和动物都较安全。有开发和推广应用价值。 相似文献
79.
G. Seghieri G. C. Bartolomei L. A. De Giorgio F. Innocenti A. Gironi M. Mian F. Franconi 《European journal of clinical pharmacology》1989,37(4):401-404
Summary Serum digoxin and beta-methyldigoxin (BMD) were measured in 165 elderly patients (age >60 years) admitted to hospital, of whom 109 had been treated at home with digoxin and 56 with BMD.The mean BMD level was significantly lower than that of digoxin (1.1 vs. 1.4 ng/ml). Creatinine clearance and daily dose were the variables most strongly associated with digoxin level, and the prescribed dose and serum albumin were the best predictors of the BMD concentration. Compliance was assessed by a compliance index (CI), namely the ratio of the measured glycoside concentration, corrected for creatinine clearance, over the expected steady-state dose, calculated from a hospitalized reference group. Compliant individuals in both treatment groups, i.e. those with a CI > the median value, were characterized by a lower daily dose and dosage frequency.Toxicity, whether clinical or electrocardiographic, was present in 9% of the patients and was associated only with a significantly higher mean serum level of the drug. 相似文献
80.
Joseph R. Holtman Jr. Nancy C. Anastasi Wesley P. Norman Kenneth L. Dretchen 《Brain research》1986,362(2)
The effect of electrical and chemical (l-glutamate) stimulation of the raphe obscurus on phrenic nerve activity was examined in the cat. Phrenic nerve activity was recorded from a C5 nerve root in anesthetized, paralyzed and artificially ventilated cats. Neural discharge was quantitated by integrating the phrenic nerve activity. The respiratory frequency was determined from the integrated nerve signal. Focal electrical stimulation (18–144 μA; 5–40 Hz; 100 μs pulse duration) resulted in significant (P < 0.05) increases in both integrated phrenic nerve (IPN) amplitude and respiratory frequency. These changes were dependent upon current intensity and frequency of stimulation. The largest increases in IPN amplitude and respiratory frequency were47 ± 17%and146 ± 8%, respectively. To insure that the changes in integrated phrenic nerve activity (IPNA) were the result of stimulation of cell bodies and not axons of passage,l-glutamate (100, 200 nmol) was microinjected (100 nl) into the raphe obscurus. Significant (P < 0.05) dose-related changes occurred in integrated phrenic nerve amplitude with an increase of44 ± 13% at 100 nmol and80 ± 13% at 200 nmoll-glutamate. No significant increase in respiratory frequency was observed withl-glutamate microinjection. The results suggest that the raphe obscurus may be involved in respiratory control. 相似文献