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51.
Didier Mathieu Alain Rahmouni Norbert Vasile Nedal Jazaerli Christophe Duvoux Jeanne Tran Van Nhieu Elie Serge Zafrani 《Journal of magnetic resonance imaging : JMRI》1994,4(3):506-508
This case report illustrates atypical magnetic resonance (MR) imaging findings in a liver hemangioma mimicking a malignant lesion—lower signal intensity than cerebrospinal fluid on T2-weighted spin-echo images and lack of early enhancement on dynamic contrast material—enhanced gradient-echo images. Pathologic analysis demonstrated nearly total replacement of the vascular cavities by dense fibrous tissue. In this rare, sclerosed form, this lesion could not be defined as a hemangioma with MR imaging. 相似文献
52.
Involvement of dendritic cells in long-term aortocoronary saphenous vein bypass graft failure. 总被引:2,自引:0,他引:2
S M Cherian Y V Bobryshev S J Inder R S Lord K H Reddi A E Farnsworth D Tran V F Munro K W Ashwell 《Cardiovascular surgery (London, England)》1999,7(5):508-518
Antigen-presenting dendritic cells are present in atherosclerotic lesions in human arterial intima, but have not been investigated in atherosclerotic and hyperplastic stenotic lesions that affect vein grafts used as arterial conduits. This study was undertaken to examine whether dendritic cells are present in aortocoronary artery saphenous vein bypass grafts affected by high-grade atheromatous stenosis. Stenotic saphenous vein coronary artery bypass grafts (angiographic luminal stenosis > 75%) were harvested from 10 patients (nine male, one female), aged 4271 years (mean 56.5) at re-do operation. The mean time interval from bypass surgery to the excision of stenotic grafts was 11.5 years (range 2-21). The specimens were fixed in 10% buffered formalin, embedded in paraffin blocks and the sections stained with antibodies to S-100 (to identify dendritic cells), CD3 (T cells), CD68 (macrophages), von Willebrand factor (endothelial cells) and alpha-smooth muscle actin (smooth muscle cells) using avidin-biotin complex immunoperoxidase technique. Normal veins were obtained during saphenous vein femoro-popliteal grafting. The stenotic venous grafts showed histological features typical of extensive arterialization, intimal hyperplasia, atherosclerotic plaque-like lesions, calcification and thrombosis. In areas of intimal hyperplasia, S-10O-positive cells were distributed irregularly among smooth muscle cells. S-100-positive dendritic cells were seen most frequently within atherosclerotic plaque-like lesions where they co-localized with CD3+ cells and CD68+ cells. S-100-positive dendritic cells were also seen accumulating within calcific foci. No S-100-positve cells were found in normal, ungrafted saphenous veins. We conclude that dendritic cells are present in aortocoronary saphenous vein bypass grafts affected by high grade stenosis. Dendritic cells are probably involved in immune mechanisms of atherogenesis through their interactions with T cells and macrophages. The accumulation of dendritic cells within calcific foci suggests their contribution to the calcification of stenotic venous grafts. 相似文献
53.
Sentinel lymph node biopsy in breast cancer: unfiltered radioisotope is superior to filtered 总被引:4,自引:0,他引:4
Linehan DC Hill AD Tran KN Yeung H Yeh SD Borgen PI Cody HS 《Journal of the American College of Surgeons》1999,188(4):377-381
BACKGROUND: The combination of gamma-probe radiolocalization and blue-dye mapping of sentinel lymph nodes (SLNs) has been advocated as the most accurate method for staging the clinically negative axilla in breast cancer patients, but the technical aspects of these procedures are not fully characterized in the literature. In this study, we compared the success of SLN localization in 134 consecutive breast cancer patients using blue dye plus two different preparations of radiocolloid. STUDY DESIGN: A retrospective analysis of a prospectively maintained data base was performed to assess SLN localization in two cohorts of patients. Unfiltered technetium-99m (Tc-99m) sulfur colloid (in 77 patients; group I) was compared with filtered Tc-99m sulfur colloid (in 57 patients; group II). All patients had a peritumoral injection of blue dye and isotope, followed immediately by lymphoscintigraphy to confirm radioactivity at the injection site and to image the SLN. Statistical analysis was performed using the Pearson chi-square test. RESULTS: Unfiltered Tc-99m sulfur colloid was superior to the filtered radiocolloid in localizing the SLN (88% versus 73%; p = 0.03). SLN imaging by lymphoscintigraphy was also more successful in the unfiltered group. Using the combination of blue dye and radiolocalization, SLNs were identified in 94% of patients. CONCLUSIONS: For optimal localization of the SLN in breast cancer patients, surgeons should use the combined technique of blue-dye mapping and gamma-probe localization using unfiltered Tc-99m sulfur colloid. 相似文献
54.
Do KS Tran GK Doan TT Nguyen TQ Do MH Do TA Nguyen VD 《Chirurgie; mémoires de l'Académie de chirurgie》1999,124(6):626-631
STUDY AIM: The aim of this study was to report the immediate results of a series of 65 hepatic resections for hepatolithiasis performed in Vietnam. PATIENTS AND METHOD: From 1986 to 1998, 44 men and 21 women (mean age: 40 years) underwent hepatic resection for hepatolithiasis. Fourty patients had previously undergone one or several operations for hepatolithiasis. The procedure was performed on emergency in 25 patients. Indications for hepatic resection were: angiocholitis and liver abscess in 22 cases, stones closely inserted in the biliary duct in 20 cases, hemobilia in 12 cases, stones located above a biliary stricture in 8 cases and stones associated with a postoperative biliary fistula in 3 cases. Liver resections (minor in 61 patients, including 55 left lobectomies, and major in 4 patients) were performed through transhepatic approach according to the Ton That Tung technique and followed by an external biliary drainage with a Kehr tube. RESULTS: There were 6 postoperative deaths (9%), 3 due to septic shock, 2 to cachexia, and 1 to liver failure. The 15 patients with complications recovered with conservative therapy. Bile infection was present in 93%, mostly with Escherichia coli and Enterobacter. Pigmented stones were usually found. CONCLUSION: Vietnam is a country with high incidence of hepatolithlasis. Hepatic resection is an adequate treatment for localized intrahepatic bile duct stones when the involved segment including biliary strictures and calculi can be completely removed. The procedure may be performed on emergency for liver abscess, or hemobilia. 相似文献
55.
56.
Sharon K. Ong'uti Gezzer Ortega Michael T. Onwugbufor Gabriel D. Ivey Terrence M. Fullum Daniel D. Tran 《Surgery for obesity and related diseases》2013,9(1):113-117
BackgroundDespite the effectiveness of Roux-en-Y gastric bypass (RYGB) in promoting excess weight loss, 40% of the patients regain weight. Endoscopic gastric plication (EGP) using the StomaphyX device can serve as a less-invasive procedure for promoting the loss of regained weight. Our objective was to evaluate the effectiveness of the StomaphyX device in sustaining ongoing weight loss in patients who have regained weight after RYGB at the Division of Minimally Invasive and Bariatric Surgery, Howard University Hospital.MethodsWe performed a retrospective chart review of patients undergoing EGP using the StomaphyX device from April 2008 to May 2010. The patient demographics and clinical information were assessed. Effective weight loss and the proportion of weight lost after EGP relative to the weight regained after achieving the lowest weight following RYGB was calculated.ResultsA total of 27 patients underwent EGP using the StomaphyX device; of these, most were women (n = 25, 93%) and black (n = 14, 52%), followed by white (n = 11, 42%), and Hispanic (n = 1, 4%). The median interval between RYGB and EGP was 6 years, with an interquartile range of 5–8 years. After the EGP procedure, the median effective weight loss was 37% (interquartile range 24–61%). Of the 27 patients, 18 had ≥6 months of follow-up after EGP. Eleven patients had achieved their lowest weight at 1–3 months, 7 at 6 months, and 3 at 12 months. Of the 18 patients, 13 (72%) experienced an increase in weight after achieving their lowest weight after EGP.ConclusionThe use of the StomaphyX device achieved the maximum effective weight loss during the 1–6-month period after EGP. 相似文献
57.
Abdollah F Sun M Jeldres C Schmitges J Thuret R Djahangirian O Tian Z Shariat SF Perrotte P Montorsi F Karakiewicz PI 《BJU international》2012,109(4):564-569
Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? To date, there is controversy about the impact of histological subtype of bladder cancer (nonbilharzial squanous cell carcinoma vs. urothelial carcinoma) on cancer control outcomes. Our study shows that the histological subtype may have an impact on the stage of bladder cancer at presentation. However, after adjusting to stage, the histological subtype has no impact on cancer control outcomes.
OBJECTIVES
- ? To test the effect of histological subtype (NBSCC vs UC) on cancer‐specific mortality (CSM), after adjusting for other‐cause mortality (OCM).
- ? In Western countries, non‐bilharzial squamous cell carcinoma (NBSCC) is the second most common histological subtype in bladder cancer (BCa) after urothelial carcinoma (UC).
PATIENTS AND METHODS
- ? We identified 12 311 patients who were treated with radical cystectomy (RC) between 1988 and 2006, within 17 Surveillance, Epidemiology and End Results (SEER) registries.
- ? Univariable and multivariable competing‐risks analyses tested the relationship between histological subtype and CSM, after accounting for OCM.
- ? Covariates consisted of age, sex, year of surgery, race, pathological T and N stages, as well as tumour grade.
RESULTS
- ? Histological subtype was NBSCC in 614 (5%) patients vs UC in 11 697 (95%) patients.
- ? At RC, the rate of non‐organ confined (NOC) BCa was higher in NBSCC patients than in their UC counterparts (71.7% vs 52.2%; P < 0.001).
- ? After adjustment for OCM, The 5‐year cumulative CSM rates were 25.0% vs 19.8% (P= 0.2) for patients with NBSCC vs UC organ confined (OC) BCa, respectively. The same rates were 46.3% vs 49.3% in patients with NOC BCa (P= 0.1).
- ? In multivariable competing‐risks analyses, histological subtype (NBSCC vs UC) failed to achieve independent predictor status of CSM in patients with OC (hazard ratio, 1.2; P= 0.06) or NOC BCa (hazard ratio, 1.1; P= 0.1).
CONCLUSIONS
- ? At RC, the rate of NOC BCa is higher in NBSCC patients than in their UC counterparts.
- ? Despite a more advanced stage at surgery, NBSCC histological subtype is not associated with a less favourable CSM than UC histological subtype, after accounting for OCM and the extent of the disease (OC vs NOC).
58.
Vanbiervliet G Filippi J Karimdjee BS Venissac N Iannelli A Rahili A Benizri E Pop D Staccini P Tran A Schneider S Mouroux J Gugenheim J Benchimol D Hébuterne X 《Surgical endoscopy》2012,26(1):53-59
Background
Migration is the most common complication of the fully covered metallic self-expanding esophageal stent (SEMS). This study aimed to determine the potential preventive effect of proximal fixation on the mucosa by clips for patients treated with fully covered SEMS.Methods
In this study, 44 patients (25 males, 57%) were treated with fully covered SEMS including 22 patients with esophageal stricture (4 malignant obstructions, 6 anastomotic strictures, and 12 peptic strictures) and 22 patients with fistulas or perforations (10 anastomotic leaks, 4 perforations, and 8 postbariatric surgery fistulas). The Hanarostent (n?=?25), Bonastent (n?=?5), Niti-S (n?=?12), and HV-stent (n?=?2) with diameters of 18 to 22?mm and lengths of 80 to 170?mm were used. Two to four clips (mean, 2.35?±?0.75 clips) were used consecutively in 23 patients to fix the upper flared end of the stent with the esophageal mucosal layer. Stent migration and its consequences were collected in the follow-up assessment with statistical analysis to compare the patients with and without clip placement.Results
No complication with clip placement was observed, and the retrieval of the stent was not unsettled by the persistence of at least one clip (12 cases). Stent migration was noted in 15 patients (34%) but in only in 3 of the 23 patients with clips (13%). The number of patients treated to prevent one stent migration was 2.23. The predictive positive value of nonmigration after placement of the clip was 87%. In the multivariate analysis, the fixation with clips was the unique independent factor for the prevention of stent migration (odds ratio, 2.3; 95% confidence interval, 0.10?C0.01; p?=?0.03).Conclusions
Anchoring of the upper flare of the fully covered SEMS with the endoscopic clip is feasible and significantly reduces stent migration. 相似文献59.
Eun-Sil Hwang MD Billur Samli MD Katherine N. Tran BA Paul P. Rosen MD Patrick I. Borgen MD Kimberly J. Van Zee MD 《Annals of surgical oncology》1998,5(8):757-763
Background: The optimal treatment of ductal carcinoma in situ (DCIS) is one of the most controversial issues in the management of breast cancer. Identification of factors that affect the risk of local recurrence is very important as the incidence of DCIS increases and the use of breast conservation becomes more widespread. Because the extent of resection may affect the relapse rate, we hypothesized that larger volumes of resection (VR) may account for the lower local recurrence rates we have previously found in elderly patients.
Methods: Between 1978 and 1990, 173 cases of histologically confirmed DCIS were treated at MSKCC with breast conservation therapy. Of these, complete VR data were available for 126 cases. The VRs thus obtained were divided into two groups, <60 cm3 and 60 cm3, and were evaluated for correlating factors. The patients were divided into three groups by age at diagnosis: younger than 40 years, 40 to 69 years, and 70 years or older.
Results: The eldest group had a significantly greater proportion of large VRs (30%) as compared to the middle group (11%) and the youngest group (9%) (P=.03, x2). Although not statistically significant, the large VR group had a lower 6-year actuarial local recurrence rate (5.6%) than did the small VR group (21.3%) (P=.16, log-rank test). This trend was observed even though adjuvant radiotherapy was used less often in patients who had large VRs.
Conclusion: Breast conservation surgery for DCIS in elderly patients is more likely to employ a large VR. This may explain, at least in part, the observation that elderly patients have a lower local recurrence rate.Presented at the 50th Annual Cancer Symposium of The Society of Surgical Oncology, Chicago, Illinois, March 20–23, 1997. 相似文献
60.
Alessandro Larcher Malek Meskawi Roger Valdivieso Katharina Boehm Vincent Trudeau Zhe Tian Nicola Fossati Paolo Dell’Oglio Giovanni Lughezzani Nicolò Buffi Maxine Sun Pierre Karakiewicz 《World journal of urology》2016,34(3):383-389