全文获取类型
收费全文 | 3627篇 |
免费 | 259篇 |
国内免费 | 146篇 |
专业分类
耳鼻咽喉 | 66篇 |
儿科学 | 55篇 |
妇产科学 | 11篇 |
基础医学 | 192篇 |
口腔科学 | 385篇 |
临床医学 | 352篇 |
内科学 | 668篇 |
皮肤病学 | 2篇 |
神经病学 | 195篇 |
特种医学 | 85篇 |
外国民族医学 | 2篇 |
外科学 | 648篇 |
综合类 | 596篇 |
预防医学 | 136篇 |
眼科学 | 45篇 |
药学 | 281篇 |
1篇 | |
中国医学 | 79篇 |
肿瘤学 | 233篇 |
出版年
2024年 | 8篇 |
2023年 | 67篇 |
2022年 | 77篇 |
2021年 | 99篇 |
2020年 | 132篇 |
2019年 | 121篇 |
2018年 | 89篇 |
2017年 | 118篇 |
2016年 | 111篇 |
2015年 | 115篇 |
2014年 | 235篇 |
2013年 | 237篇 |
2012年 | 200篇 |
2011年 | 202篇 |
2010年 | 186篇 |
2009年 | 156篇 |
2008年 | 146篇 |
2007年 | 172篇 |
2006年 | 145篇 |
2005年 | 143篇 |
2004年 | 118篇 |
2003年 | 114篇 |
2002年 | 106篇 |
2001年 | 98篇 |
2000年 | 92篇 |
1999年 | 86篇 |
1998年 | 78篇 |
1997年 | 64篇 |
1996年 | 50篇 |
1995年 | 53篇 |
1994年 | 48篇 |
1993年 | 38篇 |
1992年 | 44篇 |
1991年 | 30篇 |
1990年 | 30篇 |
1989年 | 34篇 |
1988年 | 26篇 |
1987年 | 25篇 |
1986年 | 22篇 |
1985年 | 14篇 |
1984年 | 13篇 |
1983年 | 16篇 |
1982年 | 27篇 |
1981年 | 15篇 |
1980年 | 9篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1971年 | 2篇 |
排序方式: 共有4032条查询结果,搜索用时 15 毫秒
91.
92.
93.
Ilker Sucullu Huseyin Sinan Ali Ilker Filiz Senol Yildiz Ergun Yucel Yavuz Kurt 《Journal of investigative surgery》2013,26(4):195-200
The aim of this study is to investigate the healing effect of hyperbaric oxygen (HBO) on colonic anastomoses in the presence of experimentally induced peritonitis. Thirty-two rats were allocated randomly into short-term anastomosis (STA), short-term anastomosis + HBO treatment (STA+HBO), long-term anastomosis (LTA), and long-term anastomosis + HBO (LTA+HBO) treatment groups. The STA and LTA groups were administered fluid resuscitation and antibiotics for 3 and 7 days, respectively, whereas the HBO treatment groups received additional HBO therapy for 3 and 7 days, respectively. The rats were reoperated on the third and the seventh days of anostomoses for evaluation. The bursting pressures in STA+HBO and LTA+HBO therapy groups were significantly higher than those in groups with anastomoses alone (p <. 001 and p <. 01). HBO therapy did not affect the fibrotic index neither in STA nor in LTA groups (p >. 05 for both); however, it was significantly higher in LTA+HBO group than that in STA+HBO group (p <. 05). The hydroxyproline level was significantly higher in LTA group than in STA group (p <. 05), yet HBO therapy did not affect the hydroxyproline levels in STA or LTA groups (p >. 05 for both). It is concluded that hyperbaric oxygen treatment has positive effects on colonic anastomotic healing in case of peritonitis. 相似文献
94.
Al-Ali M, Sathorn C, Parashos P. Root canal debridement efficacy of different final irrigation protocols. International Endodontic Journal,?45, 898-906, 2012. ABSTRACT: Aim To compare the smear layer and debris removal effectiveness of four root canal irrigation protocols as well as their effectiveness in removing remaining soft tissues in curved root canals. Methodology The mesiobuccal and mesial root canals of 107 extracted human maxillary and mandibular molars were instrumented using Mtwo rotary NiTi instruments then randomly divided into four groups according to a final rinse protocol: Group 1 (n?=?28) - manual agitation of 1% NaOCl and 15% EDTA; Group 2 (n?=?26) - CanalBrush agitation of 1% NaOCl and 15% EDTA; Group 3 (n?=?26) - 3% H(2) O(2) alternated with 1% NaOCl; Group 4 (n?=?27) - passive ultrasonic agitation of 1% NaOCl and 15% EDTA. All irrigation protocols were performed in a closed system. Eleven roots per group were prepared and histologically stained (H&E) to assess percentage of remaining pulpal tissues in the apical thirds. The remaining specimens were split longitudinally and examined under scanning electron microscope at ×2000 magnification to assess smear layer and debris removal. Image Pro Plus 6.0 software was used to analyse smear layer and remaining pulp tissue. Debris presence was scored by two blinded investigators using a five-point scale. Data were analysed using Univariate analysis of variance (GenStat 13, α?=?0.05). Results CanalBrush and passive ultrasonic irrigation were equally effective with significantly less smear layer and debris than manual agitation and H(2) O(2) alternated with NaOCl (P?0.05). The H(2) O(2) alternated with NaOCl protocol was significantly more effective in removing pulp tissue remnants in the apical level than manual agitation (P?=?0.009) and passive ultrasonic irrigation (P?=?0.01). Conclusions CanalBrush was as effective as passive ultrasonic irrigation in smear layer and debris removal. Alternating H(2) O(2) with NaOCl was effective in removing soft tissues from root canal complexities. Further studies are required to evaluate effectiveness of this regimen taking into account irrigant volume differences and effect of root canal system configuration. 相似文献
95.
96.
摘要:目的 探讨白花蛇舌草-半枝莲药对组分对结肠腺癌Lovo细胞增殖、侵袭、迁移和凋亡的影响及作用机制。方法 将白花蛇舌草、半枝莲按质量1∶1进行3次煎煮,获得水提物,后取适量浸膏用石油醚回流脱脂,再以乙酸乙酯进行多次萃取,获得白花蛇舌草-半枝莲药对组分,并计算得率。实验分为对照组(正常培养Lovo细胞)、白花蛇舌草-半枝莲药对组分低剂量组(10 mg/L)、中剂量组(30 mg/L)及高剂量组(50 mg/L)。通过噻唑蓝比色法(MTT)检测各组细胞培养24、48、72 h后的增殖抑制率。各组细胞培养48 h后,流式细胞仪检测细胞周期分布;Transwell实验检测细胞侵袭能力;划痕实验检测细胞迁移能力;TUNEL法检测细胞凋亡情况;Western blot法检测Grb2相关结合蛋白1(Gab1)、血管内皮生长因子受体2(VEGFR-2)、磷脂酰肌醇3-激酶(PI3K)、苏氨酸激酶(Akt)、基质金属蛋白酶-9(MMP-9)、B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)蛋白表达情况。结果 化学萃取后的白花蛇舌草-半枝莲药对中主要含有对羟基苯乙酮、野黄芩苷、木犀草素和芹菜素4种化合物,组分得率为0.61%。与对照组相比,低、中、高剂量组细胞增殖抑制率升高,G1期肿瘤细胞比例增加,细胞凋亡指数增高,侵袭细胞数和划痕闭合率明显减小(均P<0.05),细胞中Gab1、VEGFR-2、PI3K、Akt、MMP-9、Bcl-2蛋白表达降低,Bax表达升高(均P<0.05),且存在剂量依赖性。结论 白花蛇舌草-半枝莲药对组分可抑制结肠腺癌Lovo细胞的增殖,降低其迁移和侵袭能力,诱导细胞凋亡,其机制可能与抑制Gab1/VEGFR-2/PI3K/Akt信号通路活化有关。 相似文献
97.
合理的生产管理与科学施策是苜蓿获得优质高产的重要保障,本文为滴灌苜蓿优质高效生产提供参考和依据。根据作者多年的田间试验研究结果、生产实践调查及结合相关文献分析,从滴灌苜蓿田间供水、滴灌带合理布置、最佳播种期选择、施肥策略、田间生长管理、干草收获时间选择及田间干燥技术等方面,将滴灌苜蓿生产理论与实践相结合,系统阐述了绿洲区滴灌苜蓿优质高效生产的田间管理措施及注意事项,提出了滴灌苜蓿优质高效生产的管理模式与科学施策。以期为绿洲区滴灌苜蓿的优质高效生产制定合理的田间管理制度提供科学依据及实际生产指导。 相似文献
98.
99.
100.
Immunohistochemical variability of epidermal growth factor receptor (EGFR) in liver metastases from colonic carcinomas 总被引:11,自引:0,他引:11
AIMS: To follow and compare immunohistochemical expression of epidermal growth factor receptor (EGFR) in tumour cells during the entire natural history of colonic carcinoma, from primary tumour to paired lymph node and sequentially resected liver metastases; and to test interobserver reproducibility of EGFR analysis. METHODS AND RESULTS: Forty patients had resection of colonic adenocarcinoma (27 with metastatic lymph nodes) and at least one partial hepatectomy (PH) for liver metastases; a second and a third PH were performed, respectively, in 14 and three patients; seven patients had tumour liver biopsy. EGFR immunohistochemistry (n = 130) was analysed independently by two pathologists. EGFR expression (membranous staining detected in > or = 1% of tumour cells) was detected in 38/40 colonic carcinomas, 23/26 lymph nodes and 51/64 liver metastases. Both primary tumours and related metastases were EGFR+ in 28 patients (73%). Discrepancies were found in EGFR status between liver and lymph node (23%) and among the different liver samples (31%). Interobserver agreement was very good (intraclass correlation coefficients of 0.81, 0.91 and 0.85, respectively, for interpretation of staining in colon, lymph node and liver metastases). CONCLUSIONS: Since immunohistochemical detection of EGFR remains a prerequisite for EGFR-targeted therapy eligibility, different tumour samples should be tested to allow every patient a chance to take advantage of this treatment. 相似文献