全文获取类型
收费全文 | 35111篇 |
免费 | 3339篇 |
国内免费 | 2099篇 |
专业分类
耳鼻咽喉 | 302篇 |
儿科学 | 570篇 |
妇产科学 | 150篇 |
基础医学 | 1955篇 |
口腔科学 | 483篇 |
临床医学 | 4107篇 |
内科学 | 2725篇 |
皮肤病学 | 358篇 |
神经病学 | 680篇 |
特种医学 | 1090篇 |
外科学 | 3646篇 |
综合类 | 10239篇 |
现状与发展 | 9篇 |
预防医学 | 4355篇 |
眼科学 | 310篇 |
药学 | 4249篇 |
36篇 | |
中国医学 | 3652篇 |
肿瘤学 | 1633篇 |
出版年
2024年 | 169篇 |
2023年 | 383篇 |
2022年 | 1009篇 |
2021年 | 1339篇 |
2020年 | 1193篇 |
2019年 | 627篇 |
2018年 | 666篇 |
2017年 | 886篇 |
2016年 | 706篇 |
2015年 | 1251篇 |
2014年 | 1771篇 |
2013年 | 2250篇 |
2012年 | 3389篇 |
2011年 | 3428篇 |
2010年 | 3220篇 |
2009年 | 2781篇 |
2008年 | 2939篇 |
2007年 | 2803篇 |
2006年 | 2517篇 |
2005年 | 2013篇 |
2004年 | 1378篇 |
2003年 | 1106篇 |
2002年 | 817篇 |
2001年 | 784篇 |
2000年 | 603篇 |
1999年 | 231篇 |
1998年 | 30篇 |
1997年 | 52篇 |
1996年 | 35篇 |
1995年 | 20篇 |
1994年 | 49篇 |
1993年 | 22篇 |
1992年 | 15篇 |
1991年 | 15篇 |
1990年 | 8篇 |
1989年 | 12篇 |
1988年 | 2篇 |
1987年 | 14篇 |
1986年 | 9篇 |
1985年 | 5篇 |
1982年 | 1篇 |
1931年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Candida krusei发酵生产甘油过程中,菌体生长由玉米浆限制,菌体对玉米浆的得率为1.63g/g,培养其中玉米浆浓度相同时,增加渗透压或通过流加补料限制生长阶段的菌体生长,可使甘油生产阶段的比耗糖速率减慢,比耗糖速率保持在不很高的水平,可以因消耗的葡萄糖用于生长,维持,甘油和副产物形成所占比例的变化而提高甘油得率。 相似文献
22.
目的:观察督脉敷贴利斯的明透皮贴剂治疗轻中度阿尔茨海默病(AD)的临床疗效。方法:采用随机数字表法将90例轻中度AD患者分为督脉敷贴组、常规敷贴组、多奈哌齐组各30例。多奈哌齐组给予多奈哌齐片治疗,常规敷贴组给予常规敷贴利斯的明透皮贴剂治疗,督脉敷贴组给予督脉敷贴利斯的明透皮贴剂治疗。比较3组治疗前后老年性痴呆认知评定量表(ADAS-Cog)、简易智力状态检查量表(MMSE)、老年性痴呆临床总体印象量表(ADAS-CGIC)、老年性痴呆日常生活活动量表(ADAS-ADL)评分,并记录3组不良反应发生情况。结果:治疗12周、24周后,3组ADAS-CGIC、ADAS-Cog评分均较治疗前降低(P<0.05),MMSE、ADAS-ADL评分升高(P<0.05),且督脉敷贴组治疗12周、24周后ADAS-CGIC、ADAS-Cog评分低于常规敷贴组、多奈哌齐组(P<0.05),MMSE、ADAS-ADL评分高于低于常规敷贴组、多奈哌齐组(P<0.05)。常规敷贴组治疗24周后ADAS-CGIC、ADAS-Cog评分低于多奈哌齐组(P<0.05),MMSE、ADA... 相似文献
23.
慢性非特异性腰痛是康复科门诊常见疾病之一,由于其具体病理机制还未完全阐明,目前临床治疗多以对症治疗为主。张海峰主任结合自身临证经验,根据非特异性腰痛的疾病特点,认为其多是以人体体用关系失和所致。人体以一元之气为“体”,脏腑经络的外在功能为“用”。脾肾亏虚,运化失职,气化失常,气血不充,一元之气虚衰,不荣则痛,发为腰痛;气虚血瘀,阻滞经络,又或再受邪气侵犯,寒湿阻滞,不通则痛,而成本虚标实之证。张主任据此提出通补元气、化瘀止痛的治疗法则,并且结合中西医及康复物理治疗等方法,疗效甚佳。 相似文献
24.
从人膀胱上皮癌细胞株T24的亚克隆株T24-8的无血清培养上清液经55%硫酸铵沉淀,再对无离子水透析,得到了有诱导LAK 细胞活性的粗提品。有此作用的因子称为LAK 细胞诱导因子(LAK-IF)。它的分子量为67KD,等电点为pH3.1~3.5。抗人IL-6单抗不能阻断LAK-IF 的作用。LAK-IF 粗提品经Mono-Q 柱快速蛋白液相层析见3个峰。第2峰蛋白质有LAK-IF 活性。 相似文献
25.
Objective To analyse the relationship between age and treatment with captopril after acute myocardial infarction (AMI). Methods In a randomized trial, 822 patients with a first AMI received conventional medic al treatment, including intravenous thrombolytic therapy and oral aspirin or metoprolol, and then were randomly allocated to captopril [dosage fr om the first 6.25 mg to 25 mg/t.i.d, 209 younger patients (≤64 years), 269 elderly patients (65-75 years)] or conventional treatment only (131 younger p atients, 213 elderly). Survival in the four groups was calculated with the Kapl an-Meier method. Multivariate analysis was performed to understand the degree that multi-variables (including age) affect survival in patients taking captopr il in the hospital or during long term follow-up. Results The survival of patients who took captopril correlated significantly with age ( P<0.001). The survival of the elderly patients on captopril treatment did increase (P<0.0001), but not of the younger ones (P>0.05) during hosp italization. During follow-up, the survival of patients who took captopril cor related insignificantly with age (P>0.05), but both the elderly and the you n ger patients have good survival rates (all P<0.01) and lower cardiac events (all P<0.01) when they took captopril.Conclusions Captopril exerts a weak effect on the younger patients but a beneficial effect o n the elderly patients during hospitalization after AMI. However, there is no d ifference between the younger and the elderly in the prognosis, both having good survival and lower cardiac events when they take captopril long term during fol low-up. 相似文献
26.
SONG Wu WU Sui-jing HE Yu-long CAI Shi-rong ZHANG Chang-hua ZHANG Xin-hua ZHAN Wen-hua 《中华医学杂志(英文版)》2001,122(1):1486-1491
Background Previous studies have shown conflicting results on the relation between clinicopathologic features and prognosis of patients with colorectal mucinous, signet-ring cell, or non-mucinous adenocarcinoma; only few such studies have been performed in China. This retrospective study analyzed data from our department to investigate clinicopathologic characteristics, prognosis and possible correlations of three histologic types -- colorectal mucinous,signet-ring cell, and non-mucinous adenocarcinoma, to clarity the bases for observed differences which may lead to development of targeted therapies Methods Of 2079 patients diagnosed with colorectal cancer between 1994 and 2007, 144 had mucinous, 25 had signet-ring cell, and 1837 had non-mucinous adenocarcinoma. Their clinicopathologic parameters and survival were analyzed using established statistical methodologies.Results Mucinous and signet-ring cell adenocarcinomas were common in younger patients (P <0.001). Location, size and disease stage differed significantly among the three types. Signet-ring cell tumors were more commonly found in the rectum than mucinous and non-mucinous adenocarcinoma (P <0.001). Mucinous and signet-ring cell tumors presented in a later stage in life more often than non-mucinous adenocarcinoma, with lymph node involvement, serosal infiltration, peritoneal dissemination, and adjacent organ invasion (P <0.01). The rate of radical resection, hepatic metastasis and local recurrence did not differ among types (P >0.05). Compared with patients with non-mucinous adenocarcinoma, patients with mucinous and signet-ring cell tumors who underwent potentially curative resections or stage Ⅱ/Ⅲ disease had poorer long-term overall survival. Survival did not differ by type for patients with either stage Ⅰor Ⅳ disease (P >0.05). Conclusions Mucinous and signet-ring cell adenocarcinoma have unique carcinogenesis and similar biologic behavior.Our study confirms that both histologic types, especially signet-ring cell tumors, are independent, negative prognostic factors for patients with colorectal cancer. Type does not appear to have a significant effect on survival when disease is either stage Ⅰ or Ⅳ at presentation. 相似文献
27.
YANG Dong-jie HE Yu-long CAI Shi-rong PENG Jian-jun ZHANG Chang-hua ZHAN Wen-hua 《中华医学杂志(英文版)》2001,122(1):1492-1494
Background Although the indication and the timing for surgery in fulminant acute pancreatitis (FAP) are still controversial, our experience of surgical treatment for fulminant acute pancreaUtis may help improve the outcome for patients.Methods The clinical data of twenty-six patients with FAP from January 1, 2001 to October 1,2005 were analyzed. The diagnostic criteria fitted the 2007 Guidelines for the Management of Severe Acute Pancreatitis by the Chinese Medical Association.Results Twenty-six patients with FAP received surgical debridement, with a mortality rate of 42.3% (11/26). The postoperative mortalities in the >72 hour operation group and the <72 hour operation group were highly significantly different (7/8 vs 22.2% (4/18), respectively).Conclusions Early surgery may reduce the intraabdominal pressure and prevent the deterioration of FAP. An operation within 72 hours from the onset of symptoms might decrease the mortality of the disease. 相似文献
28.
29.
目的 探讨梨状窝癌局部扩展的规律 ,为梨状窝癌的手术治疗提供病理学依据。方法 应用石蜡包埋大体标本连续切片的方法 ,对 2 6例梨状窝癌全喉及次全喉切除的标本进行了观察。结果 位于梨状窝外侧壁的肿瘤 ( 4例 )主要向外侧咽侧壁扩展 ,位于梨状窝内侧壁的肿瘤 ( 5例 )容易向喉腔及对侧梨状窝扩展。累及整个梨状窝 17例。声门旁间隙及甲状软骨是最易受侵犯的喉结构 ,环状软骨受侵较少 ;会厌及会厌前间隙的侵犯未见超过中线 ,声门旁间隙及会厌前间隙的侵犯途径有2个 ,肿瘤沿杓会厌襞向前及在甲状软骨板内侧直接向前侵犯声门旁间隙 ;肿瘤沿杓会厌襞向内上方及在甲状软骨板内侧上部侵入会厌前间隙。结论 会厌前间隙的受侵并不是喉部分切除的禁忌证 ,大部分位于梨状窝外侧壁的肿瘤及部分梨状窝内侧壁的肿瘤保留喉功能是可行的 ;位于梨状窝内侧壁及环后区的肿瘤易在环后区向对侧侵犯 ,对累及环后区的梨状窝癌 (Ⅰ ,Ⅲ型 ) ,应注意肿瘤在环后区粘膜下向对侧侵犯。 相似文献
30.