全文获取类型
收费全文 | 5626篇 |
免费 | 333篇 |
国内免费 | 310篇 |
专业分类
耳鼻咽喉 | 241篇 |
儿科学 | 204篇 |
妇产科学 | 90篇 |
基础医学 | 210篇 |
口腔科学 | 147篇 |
临床医学 | 763篇 |
内科学 | 975篇 |
皮肤病学 | 14篇 |
神经病学 | 18篇 |
特种医学 | 252篇 |
外科学 | 1661篇 |
综合类 | 744篇 |
预防医学 | 141篇 |
眼科学 | 131篇 |
药学 | 297篇 |
4篇 | |
中国医学 | 92篇 |
肿瘤学 | 285篇 |
出版年
2024年 | 6篇 |
2023年 | 66篇 |
2022年 | 140篇 |
2021年 | 214篇 |
2020年 | 161篇 |
2019年 | 152篇 |
2018年 | 161篇 |
2017年 | 155篇 |
2016年 | 164篇 |
2015年 | 189篇 |
2014年 | 371篇 |
2013年 | 366篇 |
2012年 | 327篇 |
2011年 | 346篇 |
2010年 | 288篇 |
2009年 | 303篇 |
2008年 | 323篇 |
2007年 | 325篇 |
2006年 | 298篇 |
2005年 | 241篇 |
2004年 | 225篇 |
2003年 | 155篇 |
2002年 | 146篇 |
2001年 | 153篇 |
2000年 | 111篇 |
1999年 | 103篇 |
1998年 | 76篇 |
1997年 | 92篇 |
1996年 | 78篇 |
1995年 | 58篇 |
1994年 | 64篇 |
1993年 | 37篇 |
1992年 | 41篇 |
1991年 | 43篇 |
1990年 | 28篇 |
1989年 | 25篇 |
1988年 | 31篇 |
1987年 | 18篇 |
1986年 | 16篇 |
1985年 | 17篇 |
1984年 | 25篇 |
1983年 | 21篇 |
1982年 | 23篇 |
1981年 | 23篇 |
1980年 | 14篇 |
1979年 | 12篇 |
1978年 | 13篇 |
1977年 | 7篇 |
1976年 | 11篇 |
1972年 | 2篇 |
排序方式: 共有6269条查询结果,搜索用时 31 毫秒
51.
San-Chi Lin Chung-Chieh Tai Chang-Chuan Chan Jung-Der Wang 《American journal of industrial medicine》1994,26(2):221-228
A chromium electroplating worker, suffering from epistaxis during work, was found to have nasal septum perforation. To determine the etiology and prevalence of nasal septum lesions, we conducted a survey of seven chromium electroplating factories and examined 79 workers. Forty workers from three aluminum electroplating factories were also enrolled as the reference group. Subjects were thoroughly examined by an otolaryngologist and each of them provided a blood and urine sample. A questionnaire interview regarding symptoms of the upper respiratory tract, past medical history, life style, and work history was also conducted. Air chromium concentrations were measured by taking area samples for 4–6 hours. Based on field observation and chromium measurements, we divided chromium electroplating into three different exposure zones: workers directly dealing with electroplating tanks (n = 31), other process workers (n = 29), and office workers and drivers (n = 19). Among the 79 chromium electroplating workers, there were 16 cases of nasal septum perforation, and 42 with either scar formation or ulceration; 10 chromium electroplating workers developed skin ulcers after performing chrome plating. No workers from aluminum electroplating factories had any nasal septum or skin abnormalities. There was a consistent trend between the degree of chromium exposure and the signs and symptoms related to the nose, throat, and skin. Immediate improvement of occupational hygiene is warranted. 相似文献
52.
53.
54.
The site and concentration dependence of the blocking effect of Ba2+ onNecturus gallbladder epithelium has been investigated. A new approach was used which combines time-dependent electrical cell coupling
analysis with intermittently performed measurements of transepithelial and apparent intracellular impedance. From the coupling
pulse data the sum of apical and basolateral membrane conductances is obtained, which is then held constant during fitting
of the impedance data. This combination technique yields more reliable estimates of apical and basolateral membranes resistances
(R
a,R
bl) and of tight junction resistance (R
j) than our previous impedance analysis technique. Using the new approach we have found that luminal Ba2+ concentrations between 0.5 and 1.0 mmol/l increaseR
a with saturation-type kinetics without affectingR
bl andR
j, while higher luminal Ba2+ concentrations progressively increaseR
j. Corresponding effects were observed under serosal Ba2+. The results validate the new impedance analysis approach and demonstrate that millimolar concentrations of Ba2+ block tight junction conductances. Accordingly, Ba2+ can no longer be considered a tool to exclusively alter cell membrane resistances in epithelia. 相似文献
55.
L. J. Jennings G. M. Salido M. -J. Pozo J. S. Davison K. A. Sharkey R. W. Lea J. Singh 《Inflammation research》1995,44(10):447-453
We have investigated the effects of histamine on motility of the gallbladder and characterized the receptor types involved. Histamine and the histamine H1-receptor agonist, 2-thiazolylethylamine (2-TEA) contracted the isolated guinea-pig gallbladder strip in a dose dependent manner. The contractile response to histamine was shifted to the right by the H1-receptor antagonist, mepyramine. In pre-contracted gallbladder strips, the H2-receptor agonist dimaprit reduced the tension generated in a dose dependent fashion. The histamine H2-receptor antagonist, ranitidine shifted the histamine concentration effect curve to the left and attenuated the dose dependent relaxations elicited at high concentrations. The histamine H3-receptor agonist, (R)--methylhistamine (RMHA) elicited dose dependent contraction of the tissue which was significantly inhibited in the presence of mepyramine. The effects of electrical field stimulation (EFS) on the strips were not significantly altered by the presence of RMHA (10–10–10–7 M) indicating little pre-synaptic H3 activity in this tissue. Histamine immunoreactivity (IR) was detected in gallbladder whole mount preparations of the mucosa and the muscularis/serosa. The histamine IR appeared cell bound in cells of varying morphological characteristics but no IR was detected in nerve fibres or cell bodies (ganglia). Alcian blue staining was consistent with the distribution of histamine IR cells as mast cells. The results indicate that histamine is distributed in the guinea-pig gallbladder and it can regulate contractile activity via activation of H1 and H2 but not H3 receptors. 相似文献
56.
Munaza Fatima Santosh Kumar Mudassar Hussain Naveed Masood Memon Anum Vighio Muhammad Asif Syed Ambreen Chaudhry Zakir Hussain Zeeshan Iqbal Baig Mirza Amir Baig Rana Jawad Asghar Aamer Ikram Yousef Khader 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundHyderabad, Pakistan, was the first city to witness an outbreak of extensively drug resistant (XDR) typhoid fever. The outbreak strain is resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, fluoroquinolones, and third-generation cephalosporin, thus greatly limiting treatment options. However, despite over 5000 documented cases, information on mortality and morbidity has been limited.ObjectiveTo address the existing knowledge gap, this study aimed to assess the morbidity and mortality associated with XDR and non-XDR Salmonella serovar Typhi infections in Pakistan.MethodsWe reviewed the medical records of culture-confirmed typhoid cases in 5 hospitals in Hyderabad from October 1, 2016, to September 30, 2018. We recorded data on age, gender, onset of fever, physical examination, serological and microbiological test results, treatment before and during hospitalization, duration of hospitalization, complications, and deaths.ResultsA total of 1452 culture-confirmed typhoid cases, including 947 (66%) XDR typhoid cases and 505 (34%) non-XDR typhoid cases, were identified. Overall, ≥1 complications were reported in 360 (38%) patients with XDR typhoid and 89 (18%) patients with non-XDR typhoid (P<.001). Ileal perforation was the most commonly reported complication in both patients with XDR typhoid (n=210, 23%) and patients with non-XDR typhoid (n=71, 14%) (P<.001). Overall, mortality was documented among 17 (1.8%) patients with XDR S Typhi infections and 3 (0.6%) patients with non-XDR S Typhi infections (P=.06).ConclusionsAs this first XDR typhoid outbreak continues to spread, the increased duration of illness before hospitalization and increased rate of complications have important implications for clinical care and medical costs and heighten the importance of prevention and control measures. 相似文献
57.
皮下通道型胆囊肝胆管成形术治疗肝胆管结石 和胆管狭窄的临床研究 总被引:2,自引:1,他引:1
目的:总结皮下通道型胆囊肝胆管成形术的临床效果。方法:统计了1994年以来我院76例行STHG手术患者的适应症、临床效果及术后早期并发症。并选择同期实施的125 列行传统胆肠吻合(CJ)的患者进行对照。结果:STHG的手术适应症与传统胆肠吻合基本相同;STHG组患者的手术时间、住院时间、术中出血量明显少于CJ组,术后恢复良好,仅2例次并发症。结论;该术式既保存了胆囊及Oddi括约肌功能,又保证了胆汁的生理流向;防止了肠液的反,所以避免了消化功能紊乱,防止了反 流性胆管炎,对患者的影响小,是一种较为理想的治疗肝胆管结石和肝门胆管狭窄的术式。 相似文献
58.
目的:为了解决传统胆肠内引流术在治疗区域性肝胆管结石中的诸多不足。方法:设计并应用了 一种新技术式以皮下通道型胆囊肝总管吻合术替代胆肠内引流术。在切除肝脏区域性结石病灶后, 切开肝总管约1.5cm,将胆囊壶腹部切开相应大小的切口与之吻合,并适当游离胆囊,使其底部可被固定于切口皮下,建立皮下胆囊与肝内外胆管间的吻合通道。结果:已完成该术式的27例患者,手术顺利,术后恢复良好,未发现并发症。1例患者于术后1年零9个月,肝内再次发现结石且伴胆道感染症状,急诊局麻下切开皮下胆囊通道行胆道镜取石,效果满意。结论:该术式简单、方便、易行,既能保存胆囊、胆管、Oddi括约肌及胃肠道的正常生理功能, 又为术后结石复发或残留提供了一治疗新途径,且避免了传统肠吻合术的不足,因而不治疗区域性肝胆管结石的较理想的方法。 相似文献
59.
祝青 《菏泽医学专科学校学报》2001,13(4):37-38
目的 探讨上消化道穿孔修补方法的改进及疗效。方法 将5年内收治的286例上消化道穿孔病人分成A、B两组,A组行带血管蒂大网膜束填塞一针修补,大网膜束缝合覆盖;B组采用传统术式。结果 A组146例病人平均手术时间38分钟,平均住院天数8天,术后随访一年,无1例幽门狭窄或梗阻发生。B组140例病人平均手术时间52分钟,平均住院天数10天,术后随访一年,经钡餐及胃镜检查证实为术后疤痕性幽门管狭窄26例。结论 两组比较带血管蒂大网膜束填塞一针修补上消化道穿孔明显优于传统的多针修补。 相似文献
60.
目的:探讨应用IL-2型特种针进行微创穿刺术治疗后颅窝血肿的可行性及临床应用。材料及方法:回顾性分析我们自1995年9月至1999年9月对28例后颅窝高血压性或外伤性脑内血肿及硬膜外血肿进行微创穿刺引流治疗的病例。结果:28例病例中除1例于穿刺成功后死于脑干功能衰竭外,其余病例均获成功,病人无后遗症,痊愈出院,其中1例伴发再出血,经血肿腔内止血药冲洗引流治疗再出血停止,结论:此穿刺针特点为针钻一体,解决了针在颅骨上固定问题,也解决了立体定向不能留置针管问题,微创穿刺方法治疗后颅窝血肿可避免传统后颅窝开颅手术,安全性高,疗效良好,操做简便,费用较低,易于在各级医院普遍开展,具有较大推广使用价值。 相似文献