全文获取类型
收费全文 | 242654篇 |
免费 | 20454篇 |
国内免费 | 14417篇 |
专业分类
耳鼻咽喉 | 2179篇 |
儿科学 | 3074篇 |
妇产科学 | 4882篇 |
基础医学 | 28362篇 |
口腔科学 | 4218篇 |
临床医学 | 30933篇 |
内科学 | 40018篇 |
皮肤病学 | 2836篇 |
神经病学 | 13566篇 |
特种医学 | 8672篇 |
外国民族医学 | 96篇 |
外科学 | 26672篇 |
综合类 | 34086篇 |
现状与发展 | 48篇 |
一般理论 | 45篇 |
预防医学 | 15092篇 |
眼科学 | 6679篇 |
药学 | 24236篇 |
164篇 | |
中国医学 | 10923篇 |
肿瘤学 | 20744篇 |
出版年
2024年 | 709篇 |
2023年 | 3492篇 |
2022年 | 8680篇 |
2021年 | 11424篇 |
2020年 | 8394篇 |
2019年 | 7593篇 |
2018年 | 7992篇 |
2017年 | 6973篇 |
2016年 | 6665篇 |
2015年 | 10105篇 |
2014年 | 12702篇 |
2013年 | 11897篇 |
2012年 | 17536篇 |
2011年 | 19219篇 |
2010年 | 11740篇 |
2009年 | 9399篇 |
2008年 | 12764篇 |
2007年 | 12833篇 |
2006年 | 12369篇 |
2005年 | 12443篇 |
2004年 | 8605篇 |
2003年 | 7639篇 |
2002年 | 6623篇 |
2001年 | 6002篇 |
2000年 | 6111篇 |
1999年 | 6415篇 |
1998年 | 3693篇 |
1997年 | 3715篇 |
1996年 | 2841篇 |
1995年 | 2611篇 |
1994年 | 2261篇 |
1993年 | 1516篇 |
1992年 | 2298篇 |
1991年 | 2005篇 |
1990年 | 1671篇 |
1989年 | 1485篇 |
1988年 | 1291篇 |
1987年 | 1197篇 |
1986年 | 962篇 |
1985年 | 763篇 |
1984年 | 505篇 |
1983年 | 387篇 |
1982年 | 240篇 |
1981年 | 212篇 |
1980年 | 205篇 |
1979年 | 247篇 |
1978年 | 146篇 |
1977年 | 117篇 |
1976年 | 103篇 |
1974年 | 116篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
By a double-labeling method combining the retrograde tracing of horseradish peroxidase and the immunocytochemical technique, serotonin-like immunoreactive neurons in the midbrain periaqueductal gray (PAG) and nucleus raphe dorsalis (DR) of the rat were observed to send projection fibers to the nucleus parafascicularis of the thalamus bilaterally with an ipsilateral dominance. These serotonin-containing projecting neurons were observed mainly at the middle-caudal levels of the ventrolateral subdivision of the PAG and less at the middle-rostral levels of the DR. 相似文献
102.
A case of duodenojejunal intussusception secondary to a large hamartomatous polyp of Brunner's glands was reported in a 15-year-old girl. Despite a great preponderance of ileocolic intussusception in childhood, this is the first reported case of duodenojejunal intussusception occurring in that age group. The diagnosis was not made by clinical examination; complete duodenal obstruction was shown in upper gastrointestinal series and by endoscopy. The intussusception was reduced manually at laparotomy, and the polyp was excised. Pathological examination revealed a preponderance of normal-appearing Brunner's glands in the tumor, consistent with the diagnosis of Brunner's gland hamartoma. 相似文献
103.
We treated 56 consecutive acute segmental femoral shaft fractures with closed static locked nailing. 12 nails were dynamized after 6 (5-10) months due to slow fracture healing and 5 united after another 5 (3-8) months. The other 7 required cancellous bone grafting and all healed uneventfully 6 (5-8) months after grafting. Since dynamization did not promote healing in most of our cases we suggest early cancellous bone grafting in cases of delayed union. 相似文献
104.
永瓣藤化学成分的研究 总被引:2,自引:1,他引:1
永瓣藤化学成分的研究陈玲,谢平,戚薇,曾菊珍(药学系中药化学教研室)关键词永瓣藤,化学成分,三萜,蒜盘子甾酮永瓣藤(MonimopetalnmChinenseRe-hd)系卫矛科永瓣藤属植物[1],为我国特有的珍稀二类保护植物[2],分布于江西东北部... 相似文献
105.
The therapeutic response and toxic effects of chemotherapy using several doses of doxorubicin in conventional solution form or bound to an ion-exchange resin were compared in a rat tumor model, to assess the relationship of drug dose to therapeutic efficacy and associated toxicity. Single bolus injections of 3.0, 4.5, 6.0, 7.5 and 9.0 mg/kg were administered via the abdominal aorta to rats bearing hindlimb tumors. Tumor size was measured serially and the growth rates of treated groups were compared with a control growth curve. In addition, the effect of empty microspheres on tumor growth rate was assessed. The levels of circulating white blood cells were measured and compared to control levels to provide an indication of the severity of bone marrow toxicity experienced by each form of treatment. Finally, any difference in the distribution of doxorubicin to tumor, hindlimb and cardiac tissue following administration of doxorubicin as free drug or on microspheres was ascertained. Empty ion-exchange resin exerted a small although significant detrimental effect on tumor growth which may be explained by the embolization of microspheres in the precapillary blood vessels of the tumor resulting in a transient delay in tumor growth rate. The lowest dose of doxorubicin produced a significantly better therapeutic response when administered in the free drug form, but higher doses elicited an equivalent delay in tumor growth for both drug microsphere and free drug groups in a dose-dependent manner, with the maximum anti-tumor response occurring at the highest dose. Treatment with free doxorubicin at high doses resulted in significant reductions of circulating white blood cells suggesting the occurrence of bone marrow toxicity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
106.
陈富 《中国媒介生物学及控制杂志》1992,3(2):114-116
本文对59名接触实验动物大白鼠引起23例流行性出血热(EHF)的流行病学和临床症状进行了调查,发病率为38.98%。发病的有副教授、讲师、助教、研究生等。发病多在春季,年龄组在21~40岁,男多于女。经间接免疫荧光技术检查,大白鼠肺EHFV抗原阳性率为32.69%。临床分型以中型为多,其次为重型和轻型。临床症状以发热、头痛、腰痛、全身痛、食欲不振、酒醉貌为主,没有死亡病例。血清间接免疫荧光抗体IgG在1:320~1:5 120之间的占91.30%。 相似文献
107.
108.
BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a
patient's vascular access would permit routine monitoring during
haemodialysis, and hence provide information of access graft deterioration
sufficiently early to increase the success of minimally invasive remedial
procedures. This paper reports the validation of such a method in animals.
METHODS: A PTFE graft was implanted in sheep between the carotid artery and
the jugular vein. While the sheep was under general anaesthesia and on an
haemodialysis circuit, ultrasound velocity in its blood was perturbed by
the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was
measured by a transit-time blood flow meter. This flow was combined with
the areas of perturbation generated by the injection before and after
mixing in the access flow to estimate graft flow. The calculated graft flow
was compared to flow measured directly by a transit-time probe on the same
carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow
measured by ultrasound velocity dilution agreed well with graft flow
measured directly with a scatter of 76 ml/min about the regression line.
CONCLUSION: Ultrasound velocity dilution provides a method for measuring
flow in the graft accurate enough for clinical evaluation of patients on
dialysis.
相似文献
109.
T. F. Chen E. Robinson S. R. Payne E. Robinson 《Annals of the Royal College of Surgeons of England》1994,76(3):190-193
A catheter audit was performed at the Central Manchester Trust, which found that there was excessive ordering, inappropriate catheter selection by size, materials, balloon size and poor guidelines on catheter storage. From these findings and from the available literature, we have proposed guidelines on catheter selection with the aim of offering the best patient care and to provide cost efficiency which may be of benefit to other hospitals. 相似文献
110.
A W Chiu M T Chen W J Huang S T Young C Cheng S W Huang C L Chu L S Chang 《European urology》1992,22(3):250-254
Laparoscopic nephrectomy was performed in 15 male pigs, the procedure was successful in 14. Extraction of the intact kidney through a 5-cm lower abdomen incision was done in 7 animals; complete destruction and evacuation of the kidney was accomplished by a round-knife suction device through a 1-cm port in another 7 pigs. Grossly, the specimen consisted of sausage-like tubular renal tissue and a small amount of tissue debris. Pathology revealed that the glomerular and tubular structures were well preserved, no interstitial hematoma could be found. Four ports were usually used, one 1-cm umbilical camera port, one 0.5-cm port for ureter traction, and two 1-cm working ports along the midclavicular line. All the pigs recovered uneventfully. The average operation time was 3 h 20 min. The application of endo-GIA (United States Surgical Corporation) for renal hilum reduced the operative time to 2 h 20 min. Complications included renal vein tear during endoclip application and cutting in the first case, mild subcutaneous emphysema in 2 cases. This first pig received exploratory laparotomy for the repair and ligation of the renal vein. No more major complications occurred with increasing experience. From this porcine experiment, we conclude that the combination of laparoscopy, a tissue destroyer and an endobag for the entrapment of kidney seem to be a promising technique for clinical nephrectomy. 相似文献