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81.
乙基叔丁醚对动物局部和全身的毒性研究 总被引:3,自引:0,他引:3
为了主人乙基叔丁醚(ETBE)的毒性作用,探讨它的灌注溶解治疗胆固醇结石的可能性。我们做了该药物的动物毒性实验,对比ETBE和MTBE(甲基叔丁醚)对动物的局部组织和全身毒性作用。局部毒性实验是对大白兔胆囊进行灌注后,病理观察组织变化。全身毒性实验是通过对小鼠腹腔注射药物的半致死量作对比。结果发现,ETBE对兔的胆囊、胆部属这和十二指肠的损害较MTBE组动物轻。ETBE摇篮腔注射半致死量LD50) 相似文献
82.
Kodama Hideya; Fukuda Jun; Karube Hiroko; Matsui Toshihiko; Shimizu Yasushi; Tanaka Toshinobu 《Human reproduction (Oxford, England)》1995,10(8):1962-1967
This study was aimed at assessing the outcome of in-vitro fertilization(IVF) and embryo transfer in patients with polycystic ovariansyndrome (PCOS). The results of IVF and embryo transfer in PCOSpatients (PCOS group, 78 cycles of 26 patients) were comparedwith those of a control group (423 cycles in 202 patients withoutmale factor; age and ovarian stimulation protocol were matched).Although the pregnancy rate per transfer was not different inthe two groups of patients (25 versus 34%, PCOS versus controlgroup), the PCOS group had a significantly lower pregnancy rateper follicle aspiration (19 versus 31%, P < 0.05). A notableresult was a significantly higher incidence of embryo transfercancellations in the PCOS group (22 versus 8%, P < 0.01),which resulted from unpredictable failure of either oocyte recoveryor fertilization. The incidence of unexplained complete failureof fertilization was significantly higher in the PCOS group(18 versus 5%, P < 0.01). These results may reflect a reducedquality of the oocytes in the PCOS group, and there was a subgroupof PCOS patients who repeatedly produced poor results of treatment.Although the ovarian stimulation regimen best suited to PCOSpatients remains to be determined, special care should be takenduring ovarian stimulation, especially when the PCOS patientshad experienced unexplained failure of oocyte recovery or fertilizationin the previous treatment cycle(s). 相似文献
83.
Shinichiro Yasumoto Jun Tsujita Shuhei Imayama Yoshiaki Hori 《The Journal of dermatology》1996,23(7):499-501
We report a case of Gianotti-Crosti syndrome associated with human herpesvirus-6 (HHV-6) infection. An eight-month-old girl developed monomorphous papules on her cheeks, buttocks, and extremities after the subsidence of exanthema subitum. Viral antibody analysis confirmed primary HHV-6 infection. HHV-6 may be added to the list of causative agents of Gianotti-Crosti syndrome. 相似文献
84.
85.
目的 对比观察头孢噻肟(CTX)与其他两种抗菌药物治疗方案对30例血液病合并感染患者杀 菌活性(SBA)及临床疗效。方法SBA采用微量稀释法测定,临床疗效根据临床治疗登记表按三 级标准判定。结果与结论 头孢噻肟的临床反应最佳,杀菌作用时间维持较长,但对绿脓假单胞 菌和阴沟肠杆菌杀菌作用较差;呱拉西林(PIP)与阿米卡星(AN)方案的抗菌谱广,但PIP杀菌 作用时间较短,可考虑缩短给药间期,而AN可按一日一次给全日量的方案,以提高疗效减少不 良反应;头孢哌酮(CPZ)可主要用于绿脓假单胞菌感染,也可用于其它细菌的混合感染,但给药 间隔时间以一日三次为宜。 相似文献
86.
本文以 E.coli CM891为靶细胞,用细菌内抗突变作用模式研究了肉桂醛,鞣酸,二烯丙三硫的抗4NQO 突变性及其作用机制。含质粒 pKM101的 CM891的高抗株(抗50μg/ml 氨苄青霉素)能提高该菌株的自发突变率和4NQO 诱发的突变率以及对鞣酸的杀伤抗性。肉桂醛的抗突变性不依赖质粒 pKM101效应,但与暂时性生长延搁有关。鞣酸及二烯丙三硫的抗突变机制可能包括质粒 pKM101介导的易误修复。上述三种化学物中每二种联合应用均显示抗4NQO 突变性的协同效应及对靶细胞的毒性杀伤作用。 相似文献
87.
Jung Han Kim Sang Jun Lee Young Bok Han Jung Jo Moon Jong Bae Kim 《Archives of pharmacal research》1994,17(2):115-118
This paper describes the isolation of isoguanosine from Croton tiglium L. and its cytotoxic effect against several tumor cell lines in culture and newly reports that isoguanosine has an antitumor activity against implanted S-180 ascitic tumor mice. Isoguanosine is effective at the dose of 24 mg/kg/day x 5, with T/C value of 168%. Isoguanosine inhibits the growth of S-180 and Ehrlich solid tumor in mice at the optimal doses of 96 mg/kg/day x 12 and 48 mg/kg/day x 12, with 1-T/C values of 65% and 60%, respectively. 相似文献
88.
89.
Sumie Yamanaka Masanori Hashimoto Masuo Tobe Kazuo Kobayashi Jun Sekizawa Masao Nishimura 《Archives of toxicology》1990,64(4):262-268
We proposed a simple method for screening assessment of acute oral and dermal toxicity using only three rats and mice of each sex at each dose level. Animals were first treated with chemicals at a dose of 2000 mg/kg and were carefully observed for compound-related morbidity and mortality. If none of the animals died, the following toxicity tests were suspended. If some of the animals died, toxicity tests at doses of 200 and 20 mg/kg were performed. The approximate LD50 values calculated by this method showed little difference between two separate laboratories and were in good agreement with LD50 values reported in the literature. Our toxicological data also showed that LD50 values were about 2–2.5 times the MNLD (maximum non lethal dose) in acute oral and dermal toxicity. This meant that a chemical could be regarded as having an LD50 of about 4000 mg/kg or higher when there was no mortality at the dose of 2000 mg/kg. A chemical with such low toxicity would not require further testing for lethal effects. Therefore, this simple method combining the fixed-dose procedure with the limit test is suitable for determination of approximate LD50 values of chemicals and for screening for necessity for classical full LD50 test using many animals.This work was supported by a grant from Ministry of Health and Welfare in Japan (No. 467 and 511) 相似文献
90.
目的 评价一种可提高肝细胞纯度和存活率的分离培养方法。方法 以体外两步胶原酶灌流法分离肝细胞,然后将其分成两组,对照组在接种培养前不经进一步处理,试验组则在应用适宜的Percoll梯度液离心纯化之后再行培养。藉台盼蓝拒染法比较两组肝细胞的存活率,采用MTT法动态比较两组肝细胞的增殖状态,在相差显微镜下观察细胞的纯度和形态。结果 未经进一步纯化处理的猪肝细胞存活率为90%±5%,鼠肝细胞存活率为80%±5%,两者纯度均约90%;经Percoll梯度液离心纯化后,其高活力肝细胞比率均提高至98%±2%,纯度可达99%以上。从开始接种到大部分肝细胞贴壁生长,试验组比对照组肝细胞的时间有所缩短。结论 用Percoll梯度液纯化新分离肝细胞,可提高肝实质细胞的活力与纯度。 相似文献