全文获取类型
收费全文 | 9633篇 |
免费 | 537篇 |
国内免费 | 260篇 |
专业分类
耳鼻咽喉 | 37篇 |
儿科学 | 101篇 |
妇产科学 | 24篇 |
基础医学 | 269篇 |
口腔科学 | 30篇 |
临床医学 | 1237篇 |
内科学 | 2268篇 |
皮肤病学 | 57篇 |
神经病学 | 140篇 |
特种医学 | 842篇 |
外科学 | 2160篇 |
综合类 | 1700篇 |
预防医学 | 371篇 |
药学 | 878篇 |
8篇 | |
中国医学 | 168篇 |
肿瘤学 | 140篇 |
出版年
2024年 | 18篇 |
2023年 | 140篇 |
2022年 | 379篇 |
2021年 | 395篇 |
2020年 | 429篇 |
2019年 | 282篇 |
2018年 | 321篇 |
2017年 | 320篇 |
2016年 | 384篇 |
2015年 | 393篇 |
2014年 | 835篇 |
2013年 | 720篇 |
2012年 | 729篇 |
2011年 | 712篇 |
2010年 | 512篇 |
2009年 | 489篇 |
2008年 | 541篇 |
2007年 | 502篇 |
2006年 | 394篇 |
2005年 | 325篇 |
2004年 | 253篇 |
2003年 | 197篇 |
2002年 | 133篇 |
2001年 | 127篇 |
2000年 | 111篇 |
1999年 | 96篇 |
1998年 | 84篇 |
1997年 | 88篇 |
1996年 | 68篇 |
1995年 | 63篇 |
1994年 | 59篇 |
1993年 | 52篇 |
1992年 | 35篇 |
1991年 | 38篇 |
1990年 | 30篇 |
1989年 | 23篇 |
1988年 | 25篇 |
1987年 | 24篇 |
1986年 | 15篇 |
1985年 | 16篇 |
1984年 | 11篇 |
1983年 | 10篇 |
1982年 | 20篇 |
1981年 | 7篇 |
1980年 | 10篇 |
1979年 | 5篇 |
1978年 | 2篇 |
1977年 | 6篇 |
1972年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
目的: 探讨超声引导下标准通道经皮肾镜取石术(percutaneous nephrolithotomy,PCNL)治疗孤立肾肾结石患者的长期有效性和安全性。方法: 回顾性分析2008年9月至2014年6月于北京大学人民医院行PCNL治疗的22例孤立肾肾结石患者临床资料以及5年以上随访资料,记录围手术期相关指标、术后无石率(stone free rate,SFR)及并发症发生率,采用超声检查评估远期结石复发率,通过血肌酐及估计肾小球滤过率(estimated glomerular filtration rate, eGFR)评估肾功能情况。结果: 本组22例患者中,平均年龄为(50.3±11.8)岁,10例解剖性孤立肾,12例功能性孤立肾,中位结石直径为1.65(1.1~3.9) cm,全部为多发结石,包括7例鹿角形结石。术前的中位血肌酐为104.5(60.0~460.0) μmol/L,平均eGFR为(60.3±29.4) mL/min。平均手术时间为(88.2±42.0) min,各有11例单通道和双通道PCNL。术后第一天的中位血肌酐为102.0(63.0~364.0) μmol/L,平均eGFR为(58.0±25.1) mL/min,与术前相比差异均无统计学意义。术后平均住院时间为(8.7±5.2) d。本组有5例(22.7%)患者出现短期并发症,其中4例患者同时出现术后感染和大量出血,保守治疗后好转,1例患者出现胸膜损伤,行胸腔闭式引流后好转; 2例(9.1%)患者出现长期并发症,术后3个月发生输尿管狭窄,行球囊扩张术后好转;其余15例(68.2%)患者均未见并发症。中位随访时间为6.2(4.7~11.1)年,最近一次随访的中位血肌酐为104.0 (72.4~377.0) μmol/L,平均eGFR为(60.1±23.7) mL/min,与术前相比差异均无统计学意义,6例(27.3%)患者出现肾功能减退。术后初始和最终SFR分别为72.7%和100%; 6.2年的随访时间内9例(40.9%)患者结石复发,复发后共进行13次取石手术,最近一次随访的SFR为63.6%。结论: 本研究目前是国内外已有报道中关于孤立肾肾结石患者PCNL术后随访时间最长的研究,超声引导下标准通道PCNL治疗孤立肾肾结石是安全有效的,可以达到理想的SFR。长期随访结果表明仍有较高的结石复发率,但术后患者远期肾功能稳定,部分患者出现轻度肾功能减退。 相似文献
102.
为了观察经皮穿刺注射无水乙醇对肺组织的局部作用和全身影响 ,为经皮穿刺注射无水乙醇 (PEI)治疗肺癌的安全性和可行性提供依据 ,我们进行了家兔肺内PEI的初步实验研究。结果显示 :PEI后的第 1天至第 3天 ,注射局部的肺组织发生凝固性坏死 ,周围肺水肿、充血 ,伴大量嗜中性白细胞浸润。 1~ 2周后 ,肺局灶性上皮细胞肉芽组织增生 ,最后纤维化。PEI早期既无大面积肺组织坏死 ,亦无明显的全身副作用。本研究结果提示 ,肺内PEI是安全可行的 相似文献
103.
104.
目的:探讨含重组人碱性成纤维细胞生长因子(recombinant human basic fibroblast growth factor,rhbFGF)和重组人骨形态发生蛋白-2(recombinant human bone morphogenetic protein-2,rhBMP-2)骨水泥在骨质疏松性腰椎压缩性骨折(osteoporotic vertebral compression fracture,OVCF)患者经皮椎体后凸成形术(percutaneous kyphoplasty,PKP)治疗的应用价值。方法:回顾性分析2018年1月至2021年1月收治的103例行PKP手术治疗的OVCF患者,男40例,女63例;年龄61~78(65.72±3.29)岁。受伤原因:滑倒33例,跌倒42例,提重物受伤28例。根据填充骨水泥不同分为3组:磷酸钙组34例,男14例,女20例,年龄(65.1±3.3)岁,填充磷酸钙骨水泥;rhBMP-2组34例,男12例,女22例,年龄(64.8±3.2)岁,填充含rhBMP-2的骨水泥;rhbFGF+rhBMP-2组35例,男14例,女21例,年龄(65.1±3.6)岁,填充含rhbFGF和rhBMP-2的骨水泥。比较3组Oswestry 功能障碍指数(Oswestry dysfunction index,ODI)、骨密度、椎体前缘丢失高度、伤椎前缘压缩率、疼痛视觉模拟评分(visual simulation score,VAS)及再骨折发生率。结果:所有患者获得12个月随访。3组术后ODI、VAS呈下降(P<0.001),骨密度增高(P<0.001),椎体前缘丢失高度、伤椎前缘压缩率呈先下降后缓慢上升趋势(P<0.001),rhbFGF+rhBMP-2组术后第1、6、12个月ODI、VAS均低于rhBMP-2组和磷酸钙组(P<0.05),术后第6、12个月骨密度大于rhBMP-2组和磷酸钙组(P<0.05)。rhbFGF+rhBMP-2组术后第6、12个月椎体前缘丢失高度、伤椎前缘压缩率均低于rhBMP-2组和磷酸钙组(P<0.05)。3组再骨折发生率比较差异无统计学意义(P>0.05)。结论:含rhbFGF和rhBMP-2骨水泥可更有效地增加OVCF患者骨密度,获得术后满意的临床和放射学效果,显著改善临床症状。 相似文献
105.
106.
Implementation of percutaneous dilation tracheotomy – value of preincisional ultrasonic examination?
BACKGROUND: In this observational study we have evaluated the implementation of percutaneous dilation tracheotomy (PDT), using the forceps dilation technique (Portex) in a multidisciplinary ICU. METHODS: We included a preincisional ultrasonic evaluation of the neck in order to visualise the isthmus glandula thyroidea and major vessels. The observational period comprised one year. PDT was performed in 28 patients. RESULTS: Implementation of PDT was uneventful. Duration of insertion was 10 min (4-40 min). Total time of tracheostomy was 8 days (1-65 days). In nine cases, the proximal end of the isthmus was overlying the space between the 1st and 2nd tracheal ring, which was considered the optimal insertion site. This resulted in seven cases of insertion between the cricoidea and the 1st tracheal ring and in two cases in a more distal insertion. Nineteen tracheotomies were performed in the interstice between the 1st and 2nd tracheal ring. In nine patients, major vessels were overlying the trachea. In none of the patients did this information result in an altered insertion site. Two cases of minor bleeding were observed; both stopped upon compression. In two patients the primary tube size (8.0) was too big and a smaller tube had to be inserted. In one patient the tube was maladapted to the stoma and had to be interchanged with an ordinary tracheostomial tube on the 5th day of tracheostomy. CONCLUSION: Based on the experience gathered in this study and information from the literature, we have abandoned the routine use of ultrasonic examination of the neck prior to PDT. In order to achieve and maintain routine, we suggest that the procedure is performed by a restricted number of doctors. 相似文献
107.
Percutaneous endoscopic gastrostomy in burn patients 总被引:2,自引:0,他引:2
Background: Prolonged enteral feedings are required occasionally in seriously burned individuals. We have employed percutaneous endoscopic
gastrostomy (PEG) in selected patients who require particularly prolonged access, thus prompting this review.
Methods: The PEG procedure was performed under general anesthesia in combination with another surgical procedure using a variety of
commercially available needle and guidewire kits in 14 patients.
Results: These 14 patients had an average age of 55.2 ± 6.6 years and a burn involving 38 ± 8% of the body surface. Eleven of these
patients had suffered an inhalation injury. The tubes were placed an average of 57 ± 10.5 days after injury through unburned
and unharvested skin in four patients (28%), healed donor sites in five patients (35%), healed burn in one patient (1%), and
grafted burn in four patients (28%). One patient, whose catheter was placed through a grafted fascial excision, developed
moderate local wound erosion. Tubes were known to have been left in place as long as 155 days. However, most were removed
in rehabilitation hospitals, and we were unable to determine how long most were left in place. We are unaware of any problems
with the tubes occurring after discharge from the acute care setting.
Conclusions: In selected patients, PEG can provide more comfortable access for prolonged enteral feedings than nasogastric tubes and can
be placed with minimal morbidity.
Received: 29 March 1998/Accepted: 1 August 1998 相似文献
108.
Dermal exposure assessment of polycyclic aromatic hydrocarbons: in vitro percutaneous penetration from lubricating oil 总被引:2,自引:0,他引:2
Sartorelli P Cenni A Matteucci G Montomoli L Novelli MT Palmi S 《International archives of occupational and environmental health》1999,72(8):528-532
Objectives: Percutaneous penetration of polycyclic aromatic hydrocarbons (PAHs) is affected by various factors connected to exposure
conditions. The nature of the matrix, such as that of oil, can strongly affect their percutaneous penetration. Risk assessment
should consider these effects. We examined the effect of matrix on percutaneous penetration of PAHs, particularly that of
lubricating oil. Methods: The test apparatus consisted of an in vitro static diffusion cell system using full-thickness monkey (Cercopithecus aetiops) skin as the membrane and saline solution with gentamycin sulfate and 4% bovine serum albumin as receptor fluid. Chemical
analysis of PAHs in the samples obtained from cells was carried out by inverse-phase HPCL, and the results were read by spectrofluorimetry.
Results: Comparing the penetration of 13 PAHs from a lubricating oil and from acetone solution with artificial sweat resulted in a
significantly slower passage from the oil matrix for acenaphthene, anthracene, phenanthrene, fluoranthene, naphthalene, pyrene,
fluorene (Mann-Whitney U test, P < 0.05). No significant differences in the passage were found for chrysene because, in the test with oil, its concentration
was very often below the detection limit. For benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]pyrene it was possible to demonstrate a passage through the skin only when compounds were applied in acetone solution with
artificial sweat. Conclusions: The results of the study suggest the necessity of dermal penetration data relevant for risk assessment, obtained under experimental
conditions similar to the real exposure conditions.
Received: 7 January 1999 / Accepted: 10 July 1999 相似文献
109.
J. -C. Guillaume C. Prost L. Dubertret R. Touraine 《Archives of dermatological research》1981,270(1):37-47
Summary Secondary ion emission microanalysis is a new method of physical analysis recently applied in biology. The apparatus required (CAMECA SMI 300) enables pictures to be taken of the distribution of certain elements, with a space resolution of the order of 1 m. Concentrations below 1 p.p.m. are perceptible for most elements.The present results are the first obtained for human skin sections. Investigation of the natural elements of normal skin reveals no particular accumulation. Elements foreign to the skin are easy to detect. We show here the distribution in the epidermis of clinical antiseptics applied locally.This method has two advantages compared to X-ray microanalysis. It is more sensitive and allows analysis of even the lightes elements. However, its use in skin penetration studies is limited because it does not permit quantitative analysis and serious interference problems may occur.This work was supported by a grant from the INSERM (A.T.P. 677899 — Contrat No. 14) 相似文献
110.
黄伟年 《国际医药卫生导报》2003,9(18):20-22
目的观察钻颅注氧置换治疗慢性硬膜下血肿的临床疗效.方法30例患者局麻后,用颅锥穿颅骨内板,穿刺置入双腔管,先用生理盐水进行血肿冲洗,再注入氧气(每次20m1),使血肿腔内残留液体流出,如此反复操作,直至无液体换出为止.结果术后1周内全部病例的临床症状全部或绝大部分消失.术后2个月后CT复查结果全部病例血气体均基本吸收,无1例复发.随访半年,无1例复发及并发症发生.结论钻颅注氧置换治疗慢性硬膜下血肿是一种操作简便、创伤小、安全可靠、疗效显著确切、适应症宽、所需器械少、易于推广的术式. 相似文献