全文获取类型
收费全文 | 93314篇 |
免费 | 5829篇 |
国内免费 | 732篇 |
专业分类
耳鼻咽喉 | 1075篇 |
儿科学 | 2857篇 |
妇产科学 | 2295篇 |
基础医学 | 12555篇 |
口腔科学 | 2136篇 |
临床医学 | 7614篇 |
内科学 | 20412篇 |
皮肤病学 | 1983篇 |
神经病学 | 8610篇 |
特种医学 | 3734篇 |
外国民族医学 | 23篇 |
外科学 | 13125篇 |
综合类 | 1652篇 |
一般理论 | 47篇 |
预防医学 | 5354篇 |
眼科学 | 1475篇 |
药学 | 7596篇 |
3篇 | |
中国医学 | 510篇 |
肿瘤学 | 6819篇 |
出版年
2023年 | 388篇 |
2022年 | 929篇 |
2021年 | 1679篇 |
2020年 | 1095篇 |
2019年 | 1552篇 |
2018年 | 1944篇 |
2017年 | 1494篇 |
2016年 | 1563篇 |
2015年 | 1820篇 |
2014年 | 2401篇 |
2013年 | 3534篇 |
2012年 | 4670篇 |
2011年 | 4860篇 |
2010年 | 3206篇 |
2009年 | 2822篇 |
2008年 | 4314篇 |
2007年 | 4496篇 |
2006年 | 4307篇 |
2005年 | 4113篇 |
2004年 | 4447篇 |
2003年 | 4315篇 |
2002年 | 4371篇 |
2001年 | 3696篇 |
2000年 | 3652篇 |
1999年 | 2964篇 |
1998年 | 1144篇 |
1997年 | 907篇 |
1996年 | 838篇 |
1995年 | 802篇 |
1994年 | 704篇 |
1993年 | 688篇 |
1992年 | 1774篇 |
1991年 | 1754篇 |
1990年 | 1489篇 |
1989年 | 1449篇 |
1988年 | 1328篇 |
1987年 | 1199篇 |
1986年 | 1177篇 |
1985年 | 1037篇 |
1984年 | 768篇 |
1983年 | 696篇 |
1982年 | 446篇 |
1981年 | 389篇 |
1979年 | 565篇 |
1978年 | 417篇 |
1975年 | 429篇 |
1974年 | 481篇 |
1973年 | 462篇 |
1972年 | 421篇 |
1971年 | 393篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
Thirty-eight distal metatarsal osteotomies for hallux valgus in middle-aged patients between the ages of 50 and 67 years were performed over a period of five years. None of the patients could be rated with an excellent result. Good results were noted in only 52.6%. Poor results were attributable to imperfect surgical technique, severity of preoperative deformity, osteoporosis, and preexisting osteoarthritic changes at the first metatarsophalangeal joint. 相似文献
103.
The effect of laser refractive surgery on the on-field performance of professional baseball players.
BACKGROUND: The aim of this study was to determine the effect of laser refractive surgery on the offensive performance of professional baseball players. METHODS: Extensive search of the public media was conducted to determine which major league baseball players had undergone laser refractive surgery and when the procedure was performed. Baseball performance data were then used to determine presurgery and postsurgery baseball performance averages. A total of 17 position players were identified; however, 5 of these players were not considered in the analysis owing to insufficient playing experience either before or after the laser procedure. RESULTS: No statistically significant or practically significant difference was found between the presurgery and postsurgery means on either on-base percentage (P = 0.31), batting average (P = 0.39), slugging percentage (P = 0.66) or on-base plus slugging (OPS; P = 0.997) of major league baseball players. CONCLUSIONS: These preliminary findings suggest that professional baseball players should not expect a laser refractive surgical procedure to significantly improve their offensive baseball performance, despite the elimination of glasses or contact lens wear. 相似文献
104.
A M Van Hecken R Verbesselt A Buntinx V J Cirillo P J De Schepper 《British journal of clinical pharmacology》1987,23(1):84-87
Single doses of enalapril maleate 10 mg and frusemide 80 mg do not significantly affect the pharmacokinetics of each other when taken concomitantly. Their concomitant use may be associated with more adverse effects than with the individual entities. 相似文献
105.
G. Dagnelie M. J. De Vries J. Maier H. Spekreijse 《Documenta ophthalmologica. Advances in ophthalmology》1986,61(3-4):343-349
Pattern reversal stimuli are widely used for electrophysiological examination of the visual system. To investigate the mechanisms contributing to the pattern reversal EP (PREP) we performed experiments with a trained alert macaque monkey, using both contrast and motion stimuli. It was found that, as in man, for parafoveal and peripheral stimulation the PREP can be constructed from the EPs to the onset and offset of pattern motion. On the other hand foveal stimulation activates the contrast mechanism only.Our conclusion is that pattern reversal data should be considered with caution since pattern reversal can activate motion as well as contrast mechanisms. This ambiguity is not present in the pattern appearance-disappearance stimulus. 相似文献
106.
107.
Abstract: Syncope, irreversible shock, and respiratory and circulatory arrest developed in a 54-year-old diabetic man chronically dialyzed with a subclavian catheter (SC) minutes after the end of a dialysis session. Resuscitation attempts remained unsuccessful. During the resuscitation attempt, a blood analysis showed severe hyponatremia, acidosis, and hypochloremia. Respiratory and cardiac arrest developed during dialysis in a 64-year-old woman on chronic SC dialysis. Resuscitation was unsuccessful; chloremia levels were 79 mEq/L, and calcemia levels were 20 mg%. Both patients were dialyzed with a standard dialysate solution. The reasons for the electrolyte disturbances could not be explained technically. The autopsy showed myocardial perforation by the SC and accumulation in the pericardium of the fluids administered during the resuscitation attempt (e.g., glucose 5%, bicarbonate, Ca gluconate, human albumines), thus explaining the erroneous electrolyte results. The reason for the perforation was a too-rigid central femoral vein catheter, erroneously labeled a subclavian catheter by the supplying firm. Because of a syndrome of progressive vena subcla-via and vena cava sclerosis with insufficient arterial phase flow and venous-phase bleeding around the puncture site during single-needle dialysis, the original SC had to be replaced by a longer one with the tip located in the atrium (this SC was actually a femoral catheter). Analysis of the fluid aspirated through the SC can determine the diagnosis in sudden death of SC dialysis patients. 相似文献
108.
J. De Celis J. Tobaly-Tapiero A. Hampe R. Emanoil-Ravier 《Archives of virology》1994,138(3-4):345-355
Summary The complete long terminal repeat (LTR) nucleotide sequence of the chimpanzee foamy virus isolate SFV-6 was determined. Its 1761-bp size makes it the longest LTR reported to date among all retroviruses. Since the length of its LTR is similar to that of other simian isolates while its sequence homology is closer to that of HFV, SFV-6 genetic structure appears to be intermediate between simian and human foamy viruses. Transient expression assays demonstrate that SFV-6 encodes a transactivator of viral gene expression directed either by its own LTR or by heterologous promotors like HFV and HIV-1 LTRs. Our data also provide evidence for cross-transactivation between SFV-6 and HFV. 相似文献
109.
Two cases of accidental hanging that occurred at school in comparable circumstances in two three-year-olds are reported. The opposite outcomes in these two cases together with data from a review of the literature highlight the importance of first aid training to give victims of such injuries the best chance of survival. 相似文献
110.
Zuccala G.; Pahor M.; Lattanzio F.; Vagnoni S.; Rodola F.; De Sole P.; Cittadini A.; Cocchi A.; Bernabei R. 《British journal of anaesthesia》1997,79(6):776-781
The use of high-dose magnesium infusions in critically ill and surgical
patients is increasing. This practice is associated with considerable risk
of toxicity, as no reliable criteria are currently available to detect
significant intracellular magnesium depletion. We have evaluated, before
and after surgery, 33 elderly patients with hip fracture, by 24-h Holter
ECG monitoring, Doppler echocardiography and serum chemistry; lymphocyte
magnesium was measured using atomic absorption spectrophotometry. The
severity of ventricular arrhythmias increased, and serum and mononuclear
magnesium concentrations decreased significantly after surgery. Decreases
in either serum magnesium concentrations > 0.125 mmol litre-1 or
cellular magnesium > 6 nmol mg- 1, but not serum or lymphocyte absolute
magnesium concentrations, were associated with postoperative development of
repetitive arrhythmias. Variations in serum magnesium concentrations
correlated with intracellular decreases, and yielded good accuracy in
predicting the postoperative worsening of arrhythmias. Thus perioperative
differences in serum magnesium concentrations reflected intracellular
variations and allowed us to identify patients with clinically relevant
cellular magnesium depletion.
相似文献