全文获取类型
收费全文 | 10345篇 |
免费 | 570篇 |
国内免费 | 78篇 |
专业分类
耳鼻咽喉 | 116篇 |
儿科学 | 230篇 |
妇产科学 | 185篇 |
基础医学 | 1337篇 |
口腔科学 | 243篇 |
临床医学 | 1081篇 |
内科学 | 2456篇 |
皮肤病学 | 113篇 |
神经病学 | 1225篇 |
特种医学 | 353篇 |
外科学 | 1706篇 |
综合类 | 13篇 |
预防医学 | 299篇 |
眼科学 | 105篇 |
药学 | 627篇 |
中国医学 | 13篇 |
肿瘤学 | 891篇 |
出版年
2023年 | 54篇 |
2022年 | 152篇 |
2021年 | 219篇 |
2020年 | 134篇 |
2019年 | 183篇 |
2018年 | 257篇 |
2017年 | 214篇 |
2016年 | 253篇 |
2015年 | 236篇 |
2014年 | 365篇 |
2013年 | 500篇 |
2012年 | 782篇 |
2011年 | 720篇 |
2010年 | 405篇 |
2009年 | 395篇 |
2008年 | 687篇 |
2007年 | 659篇 |
2006年 | 698篇 |
2005年 | 674篇 |
2004年 | 712篇 |
2003年 | 615篇 |
2002年 | 522篇 |
2001年 | 111篇 |
2000年 | 86篇 |
1999年 | 95篇 |
1998年 | 116篇 |
1997年 | 87篇 |
1996年 | 95篇 |
1995年 | 84篇 |
1994年 | 71篇 |
1993年 | 74篇 |
1992年 | 74篇 |
1991年 | 74篇 |
1990年 | 55篇 |
1989年 | 58篇 |
1988年 | 43篇 |
1987年 | 39篇 |
1986年 | 47篇 |
1985年 | 35篇 |
1984年 | 38篇 |
1983年 | 29篇 |
1982年 | 40篇 |
1981年 | 33篇 |
1980年 | 28篇 |
1979年 | 18篇 |
1978年 | 17篇 |
1977年 | 12篇 |
1975年 | 10篇 |
1973年 | 10篇 |
1972年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
Emanuele Pilato Andrea Dell'Amore Luca Botta Giorgio Arpesella 《European journal of cardio-thoracic surgery》2007,32(1):180-182
Familial amyloidotic polyneuropathy (FAP) is an inherited disease characterized by an abnormal systemic deposition of a mutant protein called transthyretin (TTR) with elective involvement of the peripheral nervous system, but often determining cardiac, gastrointestinal, and urinary tract dysfunction. FAP commonly affects the liver and the heart until end-organs failure. Transthyretin amyloidosis is today an accepted indication for orthotopic liver transplantation (OLT). Combined heart and liver transplantation (CHLT) may be an attractive and rational treatment option when both organs are contemporary involved by this type of amyloidotic disease. Nowadays, surgical indications and techniques are far from being consolidated because only few cases of CHLT have been previously reported in literature. From November 1999 to May 2006, we performed five orthotopic combined heart and liver transplantations for FAP at our institution. Our surgical experience and clinical outcomes are herein reported. 相似文献
33.
Fabio Piscaglia Valeria Camaggi Matteo Ravaioli Gian Luca Grazi Matteo Zanello Simona Leoni Giorgio Ballardini Giulia Cavrini Antonio Daniele Pinna Luigi Bolondi 《Liver transplantation》2007,13(6):857-866
The best prioritization of patients with hepatocellular carcinoma (HCC) waiting for liver transplantation under the model for end-stage liver disease (MELD) allocation system is still being debated. We analyzed the impact of a MELD adjustment for HCC, which consisted of the addition of an extra score (based on the HCC stage and waiting time) to the native MELD score. The outcome was analyzed for 301 patients with chronic liver disease listed for liver transplantation between March 1, 2001 and February 28, 2003 [United Network for Organ Sharing (UNOS)-Child-Turcotte-Pugh (CTP) era, 163 patients, 28.8% with HCC] and between March 1, 2003 and February 28, 2004 (HCC-MELD era, 138 patients, 29.7% with HCC). In the HCC-MELD era, the cumulative dropout risk at 6 months was 17.6% for patients with HCC versus 22.3% for those patients without HCC (P = NS), similar to that in the UNOS-CTP era. The cumulative probability of transplantation at 6 months was 70.3% versus 39.0% (P = 0.005), being higher than that in the UNOS-CTP era for patients with HCC (P = 0.02). At the end of the HCC-MELD era, 12 patients with HCC (29.3%) versus 57 without HCC (58.8%) were still on the list (P = 0.001). Both native and adjusted MELD scores were higher (P < 0.05) and progressed more in patients with HCC who dropped out than in those who underwent transplantation or remained on the list (the initial-final native MELD scores were 17.3-23.1, 15.5-15.6, and 12.8-14.1, respectively). The patients without HCC remaining on the list showed stable MELD scores (initial-final: 15.1-15.4). In conclusion, the present data support the strategy of including the native MELD scores in the allocation system for HCC. This model allows the timely transplantation of patients with HCC without severely affecting the outcome of patients without HCC. 相似文献
34.
Paolo Calabresi Emesto Fedele Antonio Pisani Giovanni Fontana Nicola B. Mercuri Giorgio Bernardi Maurizio Raiteri 《The European journal of neuroscience》1995,7(9):1889-1894
Using a corticostriatal slice preparation, we have recently shown that tetanic stimulation of the corticostriatal pathway produces long-term depression (LTD) of striatal excitatory synaptic transmission. In the present study we have analysed the relationship between LTD and the striatal release of different endogenous transmitters. Samples of perfusate were collected via a small cannula placed just above the surface of the striatal slice close to the recording electrode, and were analysed by HPLC. The high-frequency stimulation (100 Hz, three trains, 3 s duration, 20 s intervals) used to induce LTD caused a significant but transient increase in the release of both excitatory (aspartate and glutamate) and inhibitory (glycine and GABA) amino acid transmitters. Tetanic stimulation also produced a significant, but transient increase in the release of endogenous dopamine. We conclude that the tetanic stimulation of the corticostriatal pathway is able to induce a large but transient release of excitatory amino acids and of dopamine, whose participation in the induction of striatal LTD has been demonstrated previously. Moreover, the maintenance of this form of synaptic plasticity does not seem to require a sustained change in transmitter release. 相似文献
35.
36.
Antonio Giorgio M.D. Luciano Tarantino Giampiero Francica Nicola Mariniello Antonio Nuzzo Luca del Viscovo Antonio Rotondo 《Cardiovascular and interventional radiology》1996,19(1):27-31
Purpose: To verify the efficacy of ultrasound (US)-guided injection of large amounts of ethanol into large or multiple liver lesions,
in a single session under general anesthesia (one-shot PEI) for percutaneous ablation of hepatic tumors.
Methods: Twenty-nine patients (27 with 51 hepatocellular carcinoma (HCC) nodules on cirrhosis, diameter range 1.0<+>–<+>9.0 cm; two
patients with a single metastasis from the gastroenteric tract, 5.0 and 9.0 cm, respectively, in diameter) were treated with
one-shot PEI.
Results: The total volume of alcohol delivered per patient ranged from 16 to 210 ml. Mean ethanol volume in all patients was 49 ml.
Dynamic computed tomography (CT) examination showed complete necrosis in 41 of 50 lesions. Two patients died of hypovolemic
shock due to massive upper gastrointestinal bleeding, 3 and 7 days, respectively, after the interventional procedure. All
the remaining patients are alive (follow-up 5<+>–<+>14 months) except one who died of liver failure 5 months after. New HCC
nodules occurred in six patients within 6 months and one intralesional relapse was recorded.
Conclusion: In this preliminary experience, one-shot PEI is as effective in inducing liver tumor necrosis as traditional PEI; its advantages
are shorter treatment time and the capability of treating larger and multiple liver lesions. 相似文献
37.
The authors review the latest theories of peripheral nerve regeneration and repair. They present their research on nerve regeneration including the alterations in the mother cell body, and in the distal part of the axon, and the time required to reach the best production of amino acids for cytoskeleton reconstruction. Other research of particular interest which is presented regards the chemotactic arrangement of motor and sensory axons inside a vein. This research has shown that the axons are able to find their way to the appropriate (sensory or motor) distal endoneural tubes.Adoption phenomena are also presented.The discussion of surgery includes the type (suture, glueing, grafts, tubulization) and the time of surgical repair. Timing and repair strategies are related to the site of the lesion (which can require that a greater or smaller amount of cytoskeleton be reconstructed), the type of the injury, the state of surrounding tissues, the age of the patients, injuries to muscles, tendons, bones, vessels and skin. A scheme of strategy is proposed. 相似文献
38.
G. Seghieri G. C. Bartolomei L. A. De Giorgio F. Innocenti A. Gironi M. Mian F. Franconi 《European journal of clinical pharmacology》1989,37(4):401-404
Summary Serum digoxin and beta-methyldigoxin (BMD) were measured in 165 elderly patients (age >60 years) admitted to hospital, of whom 109 had been treated at home with digoxin and 56 with BMD.The mean BMD level was significantly lower than that of digoxin (1.1 vs. 1.4 ng/ml). Creatinine clearance and daily dose were the variables most strongly associated with digoxin level, and the prescribed dose and serum albumin were the best predictors of the BMD concentration. Compliance was assessed by a compliance index (CI), namely the ratio of the measured glycoside concentration, corrected for creatinine clearance, over the expected steady-state dose, calculated from a hospitalized reference group. Compliant individuals in both treatment groups, i.e. those with a CI > the median value, were characterized by a lower daily dose and dosage frequency.Toxicity, whether clinical or electrocardiographic, was present in 9% of the patients and was associated only with a significantly higher mean serum level of the drug. 相似文献
39.
Giancarlo Flati Donato Flati Barbara Porowska Giorgio Rossi Sandro Francavilla Emanuele Santoro M. Carboni 《Microsurgery》1993,14(9):628-633
Circumferential choledochoplasties with vascular grafts have rarely been attempted either experimentally or in clinical practice. In this study, choledochoplasties using autologous venous and arterial grafts were performed in rats. Sixty-four rats were randomly selected into five treatment groups: A) venous interpositional graft replacement of a choledochus gap without a stent; B) venous graft with prolene stent; C) venous graft with polyethylene stent; D) arterial graft; E) a control group with simple resection between ligatures in the choledochus. The operative mortality in treatment groups B, C, D, and E, was 0, and 13% in group A. At 12 weeks follow-up, all the rats in group E had died, whereas, 52.2% (P <.05) of the rats in group A, 30% of the rats in group B, 57% of the rats in group C, and 92.8% of the rats in group D survived treatment. Surviving animals were sacrificed at 3 months for further examination. The morphology and caliber of the common bile duct of these rats were normal in 25% of the rats in group A, 33% of the rats in group B, 25% of the rats in group C, and 84.6% of the rats in group D. Proximal dilations were found in the rats presenting with abnormal morphology. The dilations were less marked in the group treated by arterial choledochoplasties. Laboratory and clinical cholestatic parameters were within normal ranges in the presence of common bile duct dilations less than four times the normal duct caliber. Electron microscopic examination of the venous and arterial graft at 3 months follow-up revealed a fibrous ring composed of collagen fibers, fibroblasts, and remnants of elastic fibers. Regenerated ductal epithelium encompassed both types of grafts. Epithelialization was more pronounced in venous grafts as compared to arterial grafts. Biliary epithelium was able to colonize the venous grafts and resume cell specialization and function as in normal biliary epithelium. The most satisfactory results were obtained using venous grafts with stents or by using arterial grafts. © 1993 Wiley-Liss Inc. 相似文献
40.
Giuseppe Micieli Marco Magri Giorgio Sandrini Cristina Tassorelli Giuseppe Nappi 《Cephalalgia : an international journal of headache》1988,8(3):193-201
In this study the variations in pupil diameter induced by different stimuli (dark-light adaptation, light reflex, electric stimulation of the sural nerve) were investigated in episodic (in the active or remission phases) and in chronic cluster headache (CH) patients. Pupil size monitoring was performed with a monocular, infrared TV pupillometer, and sural nerve stimuli were applied after the pain threshold had been measured as the flexion reflex threshold of the biceps femoris muscle (RIII reflex). The results were compared with those obtained in patients with "peripheral" (third neuron) Horner's syndrome and in healthy sex- and age-matched controls. On the symptomatic side we found an impairment of pupil response to light flashes and nociceptive stimuli; similar findings were sometimes evident on the pain-free side, too. These results substantiate previous observations that in cluster headache a dysfunction of the integrative central nervous system pathways also exists intercritically and mostly bilaterally, involving both autonomic regulation and pain perception mechanisms. 相似文献