全文获取类型
收费全文 | 8532篇 |
免费 | 353篇 |
国内免费 | 52篇 |
专业分类
耳鼻咽喉 | 79篇 |
儿科学 | 168篇 |
妇产科学 | 110篇 |
基础医学 | 1384篇 |
口腔科学 | 155篇 |
临床医学 | 740篇 |
内科学 | 2084篇 |
皮肤病学 | 116篇 |
神经病学 | 681篇 |
特种医学 | 252篇 |
外科学 | 1142篇 |
综合类 | 64篇 |
一般理论 | 3篇 |
预防医学 | 502篇 |
眼科学 | 110篇 |
药学 | 625篇 |
中国医学 | 10篇 |
肿瘤学 | 712篇 |
出版年
2023年 | 24篇 |
2022年 | 44篇 |
2021年 | 144篇 |
2020年 | 74篇 |
2019年 | 98篇 |
2018年 | 104篇 |
2017年 | 83篇 |
2016年 | 90篇 |
2015年 | 144篇 |
2014年 | 208篇 |
2013年 | 281篇 |
2012年 | 529篇 |
2011年 | 546篇 |
2010年 | 300篇 |
2009年 | 310篇 |
2008年 | 549篇 |
2007年 | 602篇 |
2006年 | 626篇 |
2005年 | 695篇 |
2004年 | 636篇 |
2003年 | 654篇 |
2002年 | 553篇 |
2001年 | 104篇 |
2000年 | 86篇 |
1999年 | 121篇 |
1998年 | 166篇 |
1997年 | 123篇 |
1996年 | 108篇 |
1995年 | 87篇 |
1994年 | 111篇 |
1993年 | 80篇 |
1992年 | 55篇 |
1991年 | 43篇 |
1990年 | 51篇 |
1989年 | 34篇 |
1988年 | 43篇 |
1987年 | 40篇 |
1986年 | 43篇 |
1985年 | 41篇 |
1984年 | 30篇 |
1983年 | 24篇 |
1982年 | 44篇 |
1981年 | 44篇 |
1980年 | 33篇 |
1979年 | 16篇 |
1978年 | 24篇 |
1977年 | 18篇 |
1976年 | 10篇 |
1974年 | 10篇 |
1973年 | 14篇 |
排序方式: 共有8937条查询结果,搜索用时 343 毫秒
101.
Jean-Luc Fellahi Bruno Valtier Alain Beauchet Jean-Pierre Bourdarias François Jardin 《Journal canadien d'anesthésie》1999,46(5):423-428
Purpose
To compare the hemodynamic effects of medical antishock trousers (MAST) inflation in mechanically ventilated patients with normal and poor left ventricular function.Methods
Twelve patients requiring respiratory support were divided into two groups according to baseline transesophageal echocardiography (TEE) measurements: normal left ventricular dimensions and fractional area of contraction (FAC=61 ± 5%) (n=7) and dilated cardiomyopathy with reduced FAC (21 ± 1%) (n=5). All patients were studied when two successive levels of load (mild load by inflation of the leg compartment of MAST at 50 cmH2O and high load by adding the abdominal compartment of MAST inflated at 30 cmH2O) were applied. Global left ventricular systolic function was assessed on the TEE transgastric short-axis view. End-systolic wall stress (ESWS) was used as an indicator of left ventricular afterload.Results
Total respiratory, lung and chest wall compliances were reduced by 48%, 51% and 27% respectively at the high load level (P < 0.05). Whereas no hemodynamic changes occurred at mild load, the high load level produced an increase in left ventricular afterload as evidenced by concomitant increases in diastolic arterial blood pressure (66 ± 6 to 79 ± 6 mmHg,P < 0.05) and ESWS (69 ± 12 to 74 ± 12 Kdyn·cm?2·m?2,P < 0.05). In patients with dilated cardiomyopathy, this increase in afterload impaired the left ventricular systolic function and end-systolic area increased (19.0 ± 2.5 to 21.4 ± 2.9 cm2·m?2,P < 0.05) while FAC decreased (22 ± 2 to 16 ± 2%,P < 0.05). Left ventricular end-diastolic area remained unchanged during the study in both groups.Conclusion
MAST inflation impairs respiratory mechanics and global left ventricular systolic function in cardiac patients without changes in left ventricular preload. 相似文献102.
We report on a symptomatic anterior intraurethral prostatic cyst in a 46-year-old man without clinical evidence of benign prostatic hyperplasia. The anterior location of this cyst makes it unique to all previously reported cases of prostatic cysts which are located posteriorly. Transurethral resection of the cyst with limited resection of the anterior prostatic tissue at the base of the cyst was performed with successful resolution of voiding symptoms. In the absence of lateral lobe hypertrophy, standard transurethral resection of the prostate should be avoided to ensure preservation of erectile and ejaculatory function. 相似文献
103.
104.
Muta M. Issa 《The Journal of urology》1996,156(2):413-419
Purpose
We studied the efficacy and safety of transurethral needle ablation of the prostate for treatment of symptomatic benign prostatic hyperplasia (BPH).Materials and Methods
A total of 12 patients with symptomatic BPH underwent transurethral needle ablation of the prostate. Voiding outcomes, including American Urological Association symptom scores, bother scores, quality of life scores, peak urinary flow rates, residual urine volumes and urodynamic pressure flows, were measured with time, and immediate and short-term (6 months) complications were assessed.Results
Transurethral needle ablation of the prostate was performed with local intraurethral lidocaine anesthesia in 11 patients and general anesthesia in 1. At 6 months there was a 61.7 percent improvement in American Urological Association symptom score (25.6 to 9.8, p = 0.0001), 61.1 percent improvement in bother score (18.8 to 7.3, p = 0.0002), 70.0 percent improvement in quality of life score (13.7 to 4.1, p = 0.0001), 73.0 percent increase in peak flow rate (7.8 to 13.5 cc per second, p less than 0.0001) and 54.9 percent decrease in the post-void residual (111 to 50 cc, p = 0.0457). Prostate volumes, maximum detrusor pressures and detrusor opening pressures decreased significantly. There were no intraoperative complications. Postoperatively, all 12 patients had mild dysuria for 1 to 7 days, 5 had transient urinary retention for 1 to 4 days, 3 had hematuria for 1 to 2 days and 1 had retrograde ejaculation.Conclusions
This initial United States trial confirms previous experience, and shows that transurethral needle ablation of the prostate appears to be a simple, safe and efficacious procedure for treatment of symptomatic BPH. In addition, it can be performed in the majority of patients using topical urethral anesthesia. 相似文献105.
By intra-adnexal injection of glucose in the rabbit embryo, we were able to stimulate all the anomalies associated with "Amniotic Disease". Since we were even able to obtain amniotic bands, this study provides an excellent experimental model of this disease. Resulting lesions occur early in development, corresponding to the first trimester of human gestation. All of the anomalies can ultimately be explained by the destruction of the most superficial cells: epiblastic cells of the embryo and the amnion, subjacent mesenchyme, and endothelial cells. The subsequent lack of interaction between these cells and the importance of the anatomical localizations of resulting hematomas can lead to the pathogenetic approach to this disease. In light of the present study, the disease appears to be caused by an external factor within the amniotic fluid. The exact nature of the destructive agent(s) remains a mystery in man. 相似文献
106.
Summary A young woman presented a mixed congenital and familial immunodeficiency syndrome consisting in an absence of IgA and lowered levels of IgG and IgM, with a defect in cellular immunity. She had a mild malabsorption syndrome with slight alterations of the jejunal mucosa. Non-caseating tuberculoid granulomata were found in skin lesions, in lymph nodes and in the spleen. At age 27 the patient died of a neurological disease of 4 months duration. Autopsy revealed a very widespread demyelinating process involving mainly the right cerebellar hemisphere but also most of the pons and left cerebellum, with the typical morphologic characters of PML. In the hemispheres lesions were limited to microscopical microglial nodules with discrete demyelination. A review of 86 published cases of PML revealed 9 other cases in which lesions showed a strong predilection for the subtentorial territories. This sampling allows for the assumption that some 11% of the cases of PML have this particular lesion distribution. Other pertinent features of this case are briefly discussed. 相似文献
107.
108.
Jean E. de La Coussaye Bruno P. Bassoul Bernard Albat Pascale A. Peray Jean-Pierre Gagnol Jean-Jacques Eledjam Antoine Sassine 《Journal canadien d'anesthésie》1992,39(2):192-197
The intravascular injection of a large dose of bupivacaine induces electrophysiological cardiac impairment, mainly by slowing ventricular conduction velocity, and haemodynamic depression, by a decrease in myocardial contractility. When cardiotoxicity occurs, succinylcholine rapidly stops convulsions. However, the possible interactions between bupivacaine and succinylcholine on cardiac electrophysiology and haemodynamic status have never been investigated. Thus, we used an experimental electrophysiological model involving closed-chest dogs. Three groups (n = 6) of pentobarbital-anaesthetized dogs were given 0.2 mg.kg-1 atropine iv. Dogs in Group 1 were given saline. The others received 4 mg.kg-1 bupivacaine iv over ten seconds. Dogs in Group 2 were then given saline and those in Group 3 were then given 2 mg.kg-1 succinylcholine iv from one to two minutes after the administration of bupivacaine. The following electrophysiological variables were measured: heart rate represented by RR interval (RR), PR, atria-His (AH), and His-ventricle (HV) intervals, QRS duration, and QT interval corrected for heart rate (QTc). The following haemodynamic variables were measured: mean aortic pressure (MAoP), the peak of the first derivative of left ventricular pressure (LV dP/dt max), and LV end diastolic pressure (LVEDP). Comparison between Groups 1 and 2 showed that bupivacaine induced more than 100% HV interval lengthening and QRS widening (P less than 0.01), prolonged QTc interval by more than 25% (P less than 0.01), and decreased LV dP/dt max by more than 50% (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
109.
Perchellet Jean-Pierre; Kishore Gollamudi S.; Conrad Elizabeth A.; Boutwell R.K. 《Carcinogenesis》1982,3(10):1149-1158
Isolated epidermal cells were incubated with a variety of compoundsknown to interfere with or alter the ultrastructure of cellsurface receptors, and the ability of 12-O-tetradecanoyl-phorbol-13-acetate(TPA) to bind to these cells and induce epidermal ornithinedecarboxylase (ODC) activity was investigated. The - and ß-adrenergicantagonists, phentolamine and propranolol, and the cholinergicantagonist, atropine, which competed effectively for the bindingreceptors of [3H]dihydro--ergocryptine, [3H]dihydroalprenolol,and [14C]acetylcholine, did not inhibit the induction of ODCactivity by TPA or the specific binding of [3H]TPA to the cells.Neuraminidase treatments caused a time- and dose- related releaseof sialic acid from the cells and enhanced the stimulatory effectof cholera toxin on basal and TPA-induced ODC activities asmuch as the monosialoganglioside GM1. Neuraminidase and theother membrane-altering agents, fucosidase, galactosidase, galactoseoxidase, phospholipases A2 and C, and NaIO4, were used aloneand/or in various combinations in our studies. All treatmentstested inhibited the specific binding of several 125I-labeledhormones and epidermal growth factor to the cells. In contrast,none of these treatments was able, in the same cell system,to affect either the binding or the biological activity of TPA.Therefore, these results suggest that the primary interactionof TPA at the plasma membrane level as well as its biologicaleffect in the intact cell do not proceed through adrenergicor cholinergic receptors and do not require the integrity ofthe cell surface glycoconjugates and phospholipids. In addition,the inhibitory effect of retinoic acid on TPA-induced ODC activityremained unaffected by some of the above treatments, suggestingthat retinoic add is unlikely to interfere with TPA interactionsat the plasma membrane level. 相似文献
110.
Jean-Pierre Famaey Jeanine Fontaine Isabelle Seaman Jean Reuse 《Naunyn-Schmiedeberg's archives of pharmacology》1979,309(2):191-195
Summary High concentrations of antiinflammatory steroids (2.5–40 g/ml) reversibly inhibited the electrically induced contractions of the guinea-pig isolated ileum. At 40 g/ml they also reversibly inhibited contractions clicited by acetylcholine, histamine, nicotine and 5-hydroxytryptamine. PGE1 (2.5 ng/ml), PGE2 (2.5 ng/ml) and PGF2 (25 ng/ml) antagonized these effects.The inhibition of contractions elicited by direct agonists were less pronounced than those elicited by indirect or partly indirect agonists. The inhibitory effect of steroids may be related to non-specific actions on biological membranes. An overall sensitization of the smooth muscle by PG's may explain their antagonism to inhibition by steroids. 相似文献