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991.
992.
Activity restrictions after posterior lumbar discectomy. A prospective study of outcomes in 152 cases with no postoperative restrictions 总被引:3,自引:0,他引:3
STUDY DESIGN: A prospective clinical trial was conducted. OBJECTIVES: To determine the feasibility of removing activity restrictions after surgery and encouraging early return to work; to ascertain the clinical and behavioral response to such a strategy; and to identify factors predictive of early return to work, preparatory to possible randomized clinical trials. SUMMARY OF BACKGROUND INFORMATION: Current practice usually entails several weeks to several months of restricted activities after lumbar discectomy to avoid disc "reinjury." Earlier work has suggested these restrictions may not be necessary. METHODS: One hundred fifty-two consecutive working patients undergoing limited open discectomy for herniated lumbar intervertebral disc were treated postoperatively with no activity restrictions. Patients were encouraged to return to full activities as soon as possible. The patients were followed for a minimum of 2 years (average follow-up time = 4.8 years). At follow-up, an independent examiner evaluated each patient and collected further postoperative data. RESULTS: One hundred forty-nine of the 152 patients (98%) returned to work. The average work loss was 1.2 weeks and 148 of 149 patients had returned to full duty by 8 weeks. Approximately one-third of the group returned to work within 1 week of surgery (32%), many the next day. Statistical analysis demonstrated very early return to work did not correlate with either recurrent sciatica, reoperation for reherniation, or ultimate clinical outcome. Seventeen patients (11.2%) had possible reherniations (recurrent sciatica) and eight underwent reoperation (5.3%). CONCLUSION: Lifting of postoperative activity restrictions after limited discectomy allowed shortened time to return to work relative to the 4 to 16 weeks commonly recommended. Complication rates appear comparable to those reported in the literature for patients under postoperative restrictions. Postoperative restrictions may not be necessary in most patients. 相似文献
993.
游离骨膜与复合rhBMP2的异种骨联合移植修复骨缺损的实验研究 总被引:6,自引:0,他引:6
目的 探讨复合基因重组人BMP2(rhBMP2)的异种骨与游离骨膜(FP)联合移植修复节段性骨缺损的效果。方法 将rhBMP2与去抗原牛松质骨载体(BCB)复合,制成rhBMP2/BCB;选用新西兰大耳白兔28只,制成烧骨干15mm缺损动物模型,分别行FP和rhBMP2/BCB复合移植(n=6)、rhBM2/BCB移植(n=6)和单纯BCB移植(n=2);术后4、8、12、16周取材,通过X线、生 相似文献
994.
The preventive effects of green tea, tea pigments, and mixed tea (a composite of whole water extract of green tea, tea polyphenols, and tea pigments) on 7,12-dimethyl-benz[a]anthracene (DMBA)-induced oral carcinogenesis in golden Syrian hamsters were studied. The right buccal pouches of animals were topically treated with 0.5% DMBA three times per week for 15 weeks. Animals were killed separately after 6, 10, and 15 weeks of DMBA treatment. Oral tumors were counted and measured, and mean tumor burden was calculated. The incidence of preneoplastic lesions and micronucleated cells, the number and volume of silver-stained nucleolar organizer regions (AgNOR), the labeling index of proliferating cell nuclear antigen, and the level of epidermal growth factor receptor expression were studied. The results showed that oral administration of 1.5% green tea, 0.1% tea pigments, and 0.5% mixed tea as the sole source of drinking water for two weeks before initiation of the DMBA treatment and until the end of the experiment significantly reduced the mean tumor burden and the incidence of dysplasia and oral carcinoma (p < 0.01). The frequency of micronucleated cells, the number of AgNOR, the total volume of AgNORs, the labeling index of proliferating cell nuclear antigen, and the level of epidermal growth factor receptor expression in the oral mucosal cells were also significantly reduced (p < 0.01). These results clearly indicated that tea preparations could effectively inhibit DMBA-induced oral carcinogenesis in hamsters. Protection from DNA damage and suppression of cell proliferation could be important mechanisms of the anticarcinogenic effects of the tea preparations. 相似文献
995.
上海市居民吸烟与癌症及有关疾病十年前瞻性研究 总被引:27,自引:0,他引:27
目的探讨上海市民吸烟与癌症及有关疾病的关系。方法80年代初在上海市区、市郊和郊县开展了居民吸烟状况的横断面调查。至1994年年底,市区研究对象随访了12年,郊区研究对象随访了11年。本次研究分析了40岁以上研究对象的随访资料,并用Poison回归模型估计吸烟因素的年龄调整相对危险度及其95%可信区间。结果市区分析结果表明,男女性吸烟者全死因的相对危险度分别为1.48、1.62。而所有癌症死亡的相对危险度男性为2.20,女性为2.00。相对危险度有统计学意义的癌症部位是肺癌、肝癌、食管癌(男)、胃癌(男)、胰腺癌(男)、膀胱癌(男)。脑血管疾病、慢性支气管炎、肺气肿和肺心病的相对危险度也见显著升高。市郊和郊县的结果与市区类似。我们估计了三个地区吸烟对男性某些疾病的归因危险度(PAR),所有死因吸烟的PAR(%)三地分别为20.9、18.9、16.3,所有癌症三地吸烟的PAR(%)分别为40.0、34.5、34.2,肺癌三地吸烟的PAR(%)分别为71.7、59.2、64.7。结论吸烟与一些癌症、慢性阻塞性肺部疾病、肺原性心脏病及脑血管病等的死亡有关 相似文献
996.
Li Hui-Qin Feng Zhuan-Chong Wang Yu-Bao Han Yiao-Lin H. Van Kets D. Wildemeersch 《Advances in Contraception》1999,15(3):201-209
The clinical performance of the new Frameless IUD was compared with the TCu380A, the most widely used copper IUD in the world today. Insertions of the Frameless IUD were conducted with a prototype inserter (Flexigard). We report on the 6-year results from a randomized comparative clinical trial conducted at the Shanghai Institute of Planned Parenthood Research, as part of an international multicenter WHO clinical trial, involving 200 women, respectively recruited for use of each device. The cumulative 6-year pregnancy rates were 0.0 per 100 women for the Frameless IUD and 3.3 for TCu380A. Termination due to partial expulsion was significantly less for the Frameless IUD as compared with TCu380A (0.0 and 4.3 per hundred women, respectively). Complete expulsion, bleeding, pain, bleeding and pain and other medical reasons for termination did not differ significantly between the two devices. The net cumulative continuation rates at six years per 100 women were 80.8 for TCu380A, and 83.0 for the Frameless IUD.Both Frameless IUD and TCu380A are highly effective, safe and acceptable contraceptive devices, because of low pregnancy rates (per 100 women), and low termination rates due to expulsion, pain, bleeding, and bleeding and pain. Due to its anchoring, the Frameless IUD is significantly more effective than the TCu380A IUD as regards proper retention of the IUD in the uterine cavity. This may also explain its lower failure rate. 相似文献
997.
以全胚胎培养模型结合免疫组化和电镜技术等探讨了乙酰水杨酸和叶酸对大鼠卵黄囊及胚胎的影响。结果表明:培养基含乙酰水杨酸300μg/ml组的卵黄囊直径和胚胎体长均显著低于阴性对照组,胚胎畸形率明显增高。组织学检查发现卵黄囊厚度变薄。间质层血岛、微血管数量明显减少,血管壁细胞不连续,血管发育不良。卵黄囊内皮层细胞顶端微绒毛少见。内皮层细胞的溶酶体、内质网及核蛋白体等结构和数量均有明显改变。而60mg/kg叶酸灌胃鼠血清与乙酰水杨酸联合应用后,则卵黄囊的上述毒性作用明显减轻或消失,提示叶酸能明显拮抗乙酰水杨酸致大鼠卵黄囊的毒性作用。 相似文献
998.
999.
1000.
人体双侧对称经络电阻抗失衡与疾病的相关研究 总被引:2,自引:0,他引:2
韩兆亮 《菏泽医学专科学校学报》1999,11(1):9-11
通过实验装置.分别测量人体双侧对称经络对称两穴位之间的电流波形,计算其电阻抗值,探讨经络的导电特性。证明了正常人双侧经络电阻抗的对称性、经络循行线的低阻性及双侧经络电阻抗失衡与其络属脏器病变的相关性等问题。 相似文献