全文获取类型
收费全文 | 11235篇 |
免费 | 642篇 |
国内免费 | 104篇 |
专业分类
耳鼻咽喉 | 106篇 |
儿科学 | 222篇 |
妇产科学 | 309篇 |
基础医学 | 1434篇 |
口腔科学 | 445篇 |
临床医学 | 901篇 |
内科学 | 2791篇 |
皮肤病学 | 134篇 |
神经病学 | 952篇 |
特种医学 | 456篇 |
外科学 | 1885篇 |
综合类 | 34篇 |
预防医学 | 484篇 |
眼科学 | 119篇 |
药学 | 671篇 |
中国医学 | 31篇 |
肿瘤学 | 1007篇 |
出版年
2024年 | 8篇 |
2023年 | 84篇 |
2022年 | 227篇 |
2021年 | 382篇 |
2020年 | 221篇 |
2019年 | 325篇 |
2018年 | 400篇 |
2017年 | 272篇 |
2016年 | 329篇 |
2015年 | 390篇 |
2014年 | 593篇 |
2013年 | 648篇 |
2012年 | 950篇 |
2011年 | 961篇 |
2010年 | 517篇 |
2009年 | 499篇 |
2008年 | 758篇 |
2007年 | 776篇 |
2006年 | 641篇 |
2005年 | 640篇 |
2004年 | 636篇 |
2003年 | 509篇 |
2002年 | 413篇 |
2001年 | 63篇 |
2000年 | 48篇 |
1999年 | 67篇 |
1998年 | 72篇 |
1997年 | 69篇 |
1996年 | 56篇 |
1995年 | 50篇 |
1994年 | 57篇 |
1993年 | 50篇 |
1992年 | 27篇 |
1991年 | 36篇 |
1990年 | 26篇 |
1989年 | 25篇 |
1988年 | 23篇 |
1987年 | 16篇 |
1986年 | 18篇 |
1985年 | 10篇 |
1984年 | 13篇 |
1983年 | 9篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1977年 | 5篇 |
1975年 | 6篇 |
1974年 | 5篇 |
1973年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Alessandro Cucchetti MD Fabio Piscaglia MD Eugenio Caturelli MD Luisa Benvegnù MD Marco Vivarelli MD Giorgio Ercolani MD Matteo Cescon MD Matteo Ravaioli MD Gian Luca Grazi MD Luigi Bolondi MD Antonio Daniele Pinna MD 《Annals of surgical oncology》2009,16(2):413-422
The presence of cirrhosis is the only risk factor that is advocated for recurrence of hepatocellular carcinoma (HCC) 2 years
after hepatic resection compared with noncirrhotic control subjects; however, data for cohorts of exclusively patients with
cirrhosis are lacking. This study was designed to assess risk factors and annual incidence of early (<2 years) and late (>2 years)
recurrence after resection of cirrhosis and to compare these findings with those of patients with cirrhosis enrolled in HCC
surveillance programs (HCC occurrence). Data from 204 patients with cirrhosis resected for HCC and 150 surveilled for cirrhosis
were retrospectively collected and compared using propensity score matching to overcome biases of nonrandomized study. Risk
factors for early recurrence (incidence = 21.8%/year) were higher serum alpha-fetoprotein (AFP) levels, poorly differentiated
tumor, and presence of microvascular invasion (P < 0.05). Risk factors for both late recurrence (18.4%/year) and HCC occurrence (3.3%/year) were male gender, older age, and
higher serum transaminase levels; multiple primary tumors and higher AFP were additional risk factors for late recurrence
and HCC occurrence respectively (P < 0.05). After propensity adjustment, resected patients with less than two risk factors for late recurrence showed an annual
incidence of HCC (6.2%/year) similar to that of surveilled patients with ≥2 risk factors (5.8%/year; P = 0.898). Early and late recurrence of HCC for patients with cirrhosis after resection have distinct risk factors. Annual
incidence of HCC 2 years or more after resection may be similar to that of general patients because the same risk factors
are involved; assessment of these characteristics could be useful in tailoring clinical management. 相似文献
92.
Filippo Catalano Antonello Trecca Luca Rodella Francesco Lombardo Anna Tomezzoli Serena Battista Marco Silano Fabio Gaj Giovanni de Manzoni 《Surgical endoscopy》2009,23(7):1581-1586
Background Endoscopic submucosal dissection (ESD) has been developed as treatment for early gastric cancer (EGC) by Japanese authors.
However, there are no reports about its possible implementation in the Western setting. The aim of the present work is to
determine the safety and efficacy of the endoscopic treatments for EGC in an Italian cohort.
Methods Forty-five patients for a total of 48 gastric lesions were enrolled in the study. Thirty-six EMR procedures were performed
with the strip biopsy technique using a double-channel endoscope. En bloc resection refers to resection in one piece, while
piecemeal refers to resections in which the lesion was removed in multiple fragments. A total of 12 ESD were performed and
completed with IT knife. We define as curative treatment lateral and vertical margins of the resected specimens free of cancer
and repeat endoscopic finding of no recurrent disease.
Results Out of 36 EMR procedures, 10 were piecemeal resections (28%), while 26 were en bloc (72%). ESD led to en bloc resection in
11/12 cases (92%). Histological assessment of curability in the EMR group was achieved in 56% of the cases, and in 92% of
the ESD group. Mean follow-up period was 31 months (range: 12–71 months). There was no local recurrence or distant metastasis
in the curative group patients.
Conclusions These results seem to confirm the safety and the clinical efficacy of the ESD procedure in the Western world too. 相似文献
93.
Luciano Potena Francesco Grigioni Gaia Magnani Paolo Ortolani Fabio Coccolo Simonetta Sassi Koen Koessels Cinzia Marrozzini Antonio Marzocchi Samuela Carigi Anna C. Musuraca Antonio Russo Carlo Magelli Angelo Branzi 《American journal of transplantation》2005,5(9):2258-2264
Although observational studies suggest that hyperhomocysteinemia may be a risk factor for coronary allograft vasculopathy (CAV), prospective data on homocysteine-lowering interventions and CAV development are lacking. We, therefore, randomized 44 de novo heart transplant (HT) recipients to 15 mg/day of 5-methyl-tetrahydrofolate (n=22), or standard therapy (control group, n=22) to investigate the effect of homocysteine lowering on the change in coronary intimal hyperplasia during the first 12 months after transplant, as detected by intra-vascular ultrasound (IVUS). Although 12 months after HT, homocysteinemia was lower in folate-treated patients (p<0.001), coronary intimal area increased similarly in the two groups (p>0.4). Conversely, hypercholesterolemia and cytomegalovirus infection were both associated with increased intimal hyperplasia (p<0.04), independently from folate intake. Sub-group analysis revealed that folate therapy reduced intimal hyperplasia in patients with hyperhomocysteinemia before randomization (n=19; p=0.02), but increased intimal hyperplasia in patients with normal homocysteine plasma concentrations (p=0.02). This bimodal effect of folate therapy persisted significantly after adjusting for cytomegalovirus infection and hypercholesterolemia. Despite effective in prevent hyperhomocysteinemia after heart transplantation, folate therapy does not seem to affect early CAV onset. However, sub-group analysis suggests that folate therapy may delay CAV development only in patients with baseline hyperhomocysteinemia, while may favor CAV progression in recipients with normal baseline homocysteinemia. 相似文献
94.
Francesco Inchingolo Marco Tatullo Fabio M Abenavoli Massimo Marrelli Alessio D Inchingolo Roberto Corelli Angelo M Inchingolo Gianna Dipalma 《Head & face medicine》2009,5(1):1-3
While the principles of eyelid reconstruction are well-established, achieving good functional and aesthetic reconstruction remains challenging. This communication presents a technique that we used on a young patient with an eyelid defect following a thermal burn. The patient was operated on to reconstruct the entire upper eyelid using, as a posterior lamella, a mucochondrial autologous graft taken from the ala of the nose as a tarsus and conjunctiva substitutes that were sutured to the Elevator palpebrae superioris aponeurosis and muscle. On the other hand, to reconstruct the anterior lamella, which consists of skin and muscle, the surgeons used a myocutaneous temporal flap taken from the region immediately lateral to the external canthus of the palpebral region, and which, after being isolated following a drawing of the upper eyelid to be reconstructed, was rotated and then sutured to the posterior lamella using the orbicularis oculi muscle as a pedicle. 相似文献
95.
Context
The use of neoadjuvant and adjuvant chemotherapy in the treatment of muscle-invasive bladder cancer is still controversial.Objective
To determine the optimal use of chemotherapy in the neoadjuvant and adjuvant settings in patients with advanced urothelial cell carcinoma. Bladder preservation is also discussed.Evidence acquisition
A critical review of the published literature on chemotherapy for patients with locally advanced bladder cancer was performed.Evidence synthesis
The presence of occult micrometastases at the time of radical cystectomy leads to both distant and local failure in patients with locally advanced transitional cell carcinoma of the bladder. Both neoadjuvant and adjuvant therapies have been evaluated in patients with locally advanced bladder cancer. Studies evaluating adjuvant chemotherapy have been limited by inadequate statistical power to detect meaningful clinical answers as well as by experimental arms utilizing inadequate chemotherapy.Conclusions
The aggregate of available evidence suggests that neoadjuvant cisplatin-based combination chemotherapy should be considered as a standard of care for patients with muscle-invasive or locally advanced operable bladder cancer. In patients who are either unfit for or refuse radical cystectomy, neoadjuvant chemotherapy with or without radiation can render bladder preservation possible for patients who attain an excellent clinical response. With the introduction of new cytotoxic drugs, there is a need for well-designed studies to address the optimal utility of perioperative therapy in high-risk patients with bladder cancer. 相似文献96.
Fabio Becce MD Delphine Richarme MD Patrick Omoumi MD MSc Ali Djahangiri MD Alain Farron MD Reto Meuli MD PhD Nicolas Theumann MD 《Journal of magnetic resonance imaging : JMRI》2013,37(5):1228-1233
Purpose:
To assess the value of adding axial traction to direct MR arthrography of the shoulder, in terms of subacromial and glenohumeral joint space widths, and coverage of the superior labrum‐biceps tendon complex and articular cartilage by contrast material.Materials and Methods:
Twenty‐one patients investigated by direct MR arthrography of the shoulder were prospectively included. Studies were performed with a 3 Tesla (T) unit and included a three‐dimensional isotropic fat‐suppressed T1‐weighted gradient‐recalled echo sequence, without and with axial traction (4 kg). Two radiologists independently measured the width of the subacromial, superior, and inferior glenohumeral joint spaces. They subsequently rated the amount of contrast material around the superior labrum‐biceps tendon complex and between glenohumeral cartilage surfaces, using a three‐point scale: 0 = no, 1 = partial, 2 = full.Results:
Under traction, the subacromial (Δ = 2.0 mm, P = 0.0003), superior (Δ = 0.7 mm, P = 0.0001) and inferior (Δ = 1.4 mm, P = 0.0006) glenohumeral joint space widths were all significantly increased, and both readers noted significantly more contrast material around the superior labrum‐biceps tendon complex (P = 0.014), and between the superior (P = 0.001) and inferior (P = 0.025) glenohumeral cartilage surfaces.Conclusion:
Direct MR arthrography of the shoulder under axial traction increases subacromial and glenohumeral joint space widths, and prompts better coverage of the superior labrum‐biceps tendon complex and articular cartilage by contrast material. J. Magn. Reson. Imaging 2013;37:1228–1233. © 2012 Wiley Periodicals, Inc. 相似文献97.
Laparoscopic surgery decreases postoperative pain, shortens hospital stay, and returns patients to full functional status more quickly than open surgery in a variety of surgical procedures. This study was undertaken to evaluate laparoscopic techniques as applied to aortic surgery. Nine patients underwent elective hand-assisted laparoscopic surgery, 8 for obliterative disease and 1 for an aneurysm of the abdominal aorta. Five patients had a left aorto-femoral bypass, 3 patients an aorto-bifemoral bypass, and 1 patient an aorto-aortic bypass after aneurysmectomy. There were no laparotomic conversions and all procedures were completed with transperitoneal hand-assisted laparoscopic surgery. Mean aortic clamping time was 39 minutes and mean operative time 194 minutes. Mean blood loss was 500 ml and the mean postoperative hospital stay was 4.2 days without major complications. At control examinations all grafts were patent. Hand-assisted laparoscopic aortic surgery is feasible, safe, and effective. In selected cases it may be a valid surgical procedure in addition to conventional and endovascular surgery. The advantages observed in our patients were minimal tissue trauma, less postoperative pain and faster postoperative recovery. 相似文献
98.
Pasqual E Bacchetti S Waclaw B Bertolissi F Grimaldi F Cagol PP 《Chirurgia italiana》2003,55(1):29-34
Adrenalectomy represents the gold standard treatment for hyperfunctioning adrenal incidentaloma. In cases of silent adrenal masses, on the other hand, the surgical removal of an adrenocortical cancer entails the sacrifice of a large number of safe benign masses, and in most cases surgery is therefore unjustified. The aim of this paper was to clarify the surgical indications for adrenal incidentaloma by reviewing our experience in comparison with the main reference literature. Over the period from 1995 to 2001 we managed 40 cases of incidentaloma. US and CT abdominal scans, adrenal scintigraphy and biochemical tests were performed on an outpatient basis. Seven pre-Cushing syndromes were removed. Ten incidentalomas measured 4 cm or more in diameter: 5 of these were operated on and in 5 cases surgery was not feasible or was refused. Only one malignant mass was detected (an angiosarcoma). Four postoperative minimal complications (18.7%) were observed. The follow-up (median: 48 months) was uneventful. The surgical approach was traditional in 11 cases and laparoscopic in 1 case. Surgery should be considered mandatory in cases of hyperfunctioning adrenal masses in the presence of suspect radiological evidence, in cases of discordant CT and scintigraphy findings and when the maximum diameter is 4 cm or more. 相似文献
99.
Predictors of renal and patient outcomes in atheroembolic renal disease: a prospective study 总被引:3,自引:0,他引:3
Scolari F Ravani P Pola A Guerini S Zubani R Movilli E Savoldi S Malberti F Maiorca R 《Journal of the American Society of Nephrology : JASN》2003,14(6):1584-1590
Atheroembolic renal disease (AERD) is part of a multisystemic disease accompanied by high cardiovascular comorbidity and mortality. Interrelationships between traditional risk factors for atherosclerosis, vascular comorbidities, precipitating factors, and markers of clinical severity of the disease in determining outcome remain poorly understood. Patients with AERD presenting to a single center between 1996 and 2002 were followed-up with prospective collection of clinical and biochemical data. The major outcomes included end-stage renal disease (ESRD) and death. Ninety-five patients were identified (81 male). AERD was iatrogenic in 87%. Mean age was 71.4 yr. Twenty-three patients (24%) developed ESRD; 36 patients (37.9%) died. Cox regression analysis showed that significant independent predictors of ESRD were long-standing hypertension (hazard ratio [HR] = 1.1; P < 0.001) and preexisting chronic renal impairment (HR = 2.12; P = 0.02); use of statins was independently associated with decreased risk of ESRD (HR = 0.02; P = 0.003). Age (HR = 1.09; P = 0.009), diabetes (HR = 2.55; P = 0.034), and ESRD (HR = 2.21; P = 0.029) were independent risk factors for patient mortality; male gender was independently associated with decreased risk of death (HR = 0.27; P = 0.007). Cardiovascular comorbidities, precipitating factors, and clinical severity of AERD had no prognostic impact on renal and patient survival. It is concluded that AERD has a strong clinical impact on patient and renal survival. The study clearly shows the importance of preexisting chronic renal impairment in determining both renal and patient outcome, this latter being mediated by the development of ESRD. The protective effect of statins on the development of ESRD should be evaluated in a prospective study. 相似文献
100.
Prifti E Bonacchi M Giunti G Frati G Leacche M Bartolozzi F 《Journal of cardiac surgery》2003,18(5):375-383
OBJECTIVE: The aim of this study is to evaluate in a cohort of patients with impaired left ventricular (LV) function and ischemic mitral valve regurgitation (MVR), the effects of on-pump/beating heart versus conventional surgery in terms of postoperative mortality and morbidity and LV function improvement. MATERIALS AND METHODS: Between January 1993 and February 2001, 91 patients with LVEF between 17% and 35% and chronic ischemic MVR (grade III-IV), underwent MV repair in concomitance with coronary artery bypass grafting (CABG) Sixty-one patients (Group I) underwent cardiac surgery with cardioplegic arrest, and 30 patients (Group II) underwent beating heart combined surgery. Aortic valve insufficiency was considered a contraindication for the on-pump/beating heart procedure. Mean age in Group I was 64.4 +/- 7 years and in Group II, 65 +/- 6 years (p = 0.69). RESULTS: The in-hospital mortality in Group I was 8 (13%) patients versus 2 (7%) patients in Group II (p > 0.1). The cardiopulmonary bypass (CPB) time was significantly higher in Group I (p < 0.001). In Groups I and II, respectively (p > 0.1), 2.5 +/- 1 and 2.7 +/- 0.8 grafts per patient were employed. Perioperative complications were identified in 37 (60.7%) patients in Group I versus 10 (33%) patients in Group II (p = 0.025). Prolonged inotropic support of greater than 24 hours was needed in 48 (78.7%) patients (Group I) versus 15 (50%) patients (Group II) (p = 0.008). Postoperative IABP and low cardiac output incidence were significantly higher in Group I, p = 0.03 and p = 0.027, respectively. Postoperative bleeding greater than 1000 mL was identified in 24 patients (39.4%) in Group I versus 5 (16.7%) in Group II (p = 0.033). Renal dysfunction incidence was 65.6% (40 patients) in Group I versus 36.7% (11 patients) in Group II (p = 0.013). The echocardiographic examination within six postoperative months revealed a significant improvement of MV regurgitation fraction, LV function, and reduced dimensions in both groups. The postoperative RF was significantly lower in Group II patients 12 +/- 6 (%) versus 16 +/- 5.6 (%) in Group I (p = 0.001). The 1, 2, and 3 years actuarial survival including all deaths was 91.3%, 84.2%, and 70% in Group I and 93.3%, 87.1%, and 75% in Group II (p = ns). NYHA FC improved significantly in all patients from both groups. CONCLUSION: We conclude that patients with impaired LV function and ischemic MVR may undergo combined surgery with acceptable mortality and morbidity. The on/pump beating heart MV repair simultaneous to CABG offers an acceptable postoperative outcome in selected patients. 相似文献