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991.

Background

The role of laparoscopic surgery for locally advanced colorectal cancer invading or adhering to neighboring organs is controversial. This study evaluated the safety and feasibility of laparoscopic multivisceral resection for colorectal cancer.

Methods

This study included 126 patients who underwent multivisceral resection for primary colorectal cancer invading or adhering to neighboring organs or structures between July 2005 and November 2012 at our institution. Perioperative outcomes were compared between laparoscopic and open resections.

Results

Laparoscopic and open multivisceral resections were performed in 60 and 66 patients, respectively. Conversion to open surgery occurred in 6.7 % of patients. The median operative time was significantly longer (271 vs. 227 min), but the median blood loss was significantly less (40 vs. 205 mL), in the laparoscopic compared with the open group. The R0 resection rate of the primary tumor (95 vs. 98.5 %), number of lymph nodes harvested (18 vs. 18), and postoperative complications (28 vs. 24 %) were comparable between the groups. The median length of hospital stay was significantly shorter (13.5 vs. 18 days) in the laparoscopic compared with the open group.

Conclusions

Laparoscopic multivisceral resection for colorectal cancer invading or adhering to neighboring organs is safe and feasible in selected patients.  相似文献   
992.
This study was conducted to examine the efficacy of duct-to-mucosal pancreaticojejunostomy compared with external stented pancreaticojejunostomy in prevention of several complications, retrospectively. Seventy-six patients with pancreatic head resection (59 male; median age, 60.1 years) underwent pancreaticoduodenectomy at the Second Department of Surgery, Wakayama Medical University, School of Medicine, Wakayama, Japan, between January 1, 1994, and March 31, 2002. In early postoperative status, the incidence of pancreatic fistula by duct-to-mucosal anastomosis (n = 45) was similar to that by external stent (n = 31); soft pancreas is a risk factor of pancreatic fistula compared with hard pancreas (p < 0.05). During the late postoperative period, however, no patients with duct-to-mucosal anastomosis showed pancreatic duct dilatation by computed tomography (CT). At the same time, 58.8% of patients with external stent followed by CT showed pancreatic duct dilatation (p < 0.01). The duct-to-mucosal anastomosis was more effective pancreaticojejunostomy than the external stent in terms of prevention of pancreatic duct dilatation, and it should be the surgical procedure of choice in pancreaticoduodenectomy.  相似文献   
993.

Background

Cinacalcet markedly reduces the serum intact parathyroid hormone (PTH) level of hemodialysis (HD) patients with secondary hyperparathyroidism. Parathyroidectomy also reduces the serum intact PTH level of HD patients and it increases their bone mineral density (BMD). However, there is little information about the effect of cinacalcet on BMD or on the associations between bone markers and BMD in HD patients.

Methods

We performed a 1-year cohort study of 25 HD patients who had a serum intact PTH level above 300 pg/ml during treatment by conventional therapies, such as with active vitamin D, and cinacalcet was prescribed for 14 of them. BMD of the femoral neck and the serum levels of two circulating bone markers, alkaline phosphatase (ALP) and bone-specific alkaline phosphatase (BSAP), were measured before and after treatment. The other 11 HD patients without cinacalcet treatment were defined as control group.

Results

BMD significantly increased by 7.3 % during the 1 year of treatment in the cinacalcet group and decreased by 6.2 % during the same period in the control group, and cinacalcet therapy was independently associated with the changes in BMD after multiple regression analysis that included intact PTH (β = 7.57, P < 0.01). In the cinacalcet group, the serum ALP levels (R 2 = 0.315, P < 0.05) and BSAP levels (R 2 = 0.682, P < 0.01) levels were significantly negatively correlated with the changes in BMD, but the serum intact PTH levels were not significantly associated with the changes in BMD (R 2 = 0.011, P = 0.72).

Conclusions

One year of treatment with cinacalcet increased the BMD of the femoral neck in the HD cohort, especially in the patients who had higher serum ALP and BSAP levels at baseline.  相似文献   
994.
Carotid endarterectomy (CEA) is intended to remove atheromatous plaque by dissecting a plane between the intima and the media (circular medial fibers), but this may not be the optimal dissection plane. The present technique is based on identifying the plane that divides the media from the plaque, so preserving the media on the adventitia as much as possible. This plane is more difficult to find and follow than the easy-to-dissect plane usually located between the media and the adventitia, because the plaque invades the media and so the dividing plane is located within the media. In this prospective observational study, CEA was performed in 22 patients to histologically examine the excised plaques and small samples of the whole arterial wall, and evaluate the clinical outcomes. Plaque had invaded the luminal part of the media in the whole arterial wall sample of 80% of cases. Thin medial layers covering > 80% of the surface of the plaque were found in 16 of 22 plaques (73%). Some atheromatous component was sometimes left in the preserved media, rather than completely removed with the media. No morbidity or mortality had occurred by discharge. Only 1 small ipsilateral infarction (4.5%) and no restenosis of greater than 50% were detected during the mean follow-up period of 7 years. Since the plaque usually invades the media, the optimum dissection plane may be located within the media, dividing it into two layers. The presence of some remnant atheromatous components in the preserved media was not associated with surgical complications or restenosis.  相似文献   
995.
The accurate calculation of hepatic volume by computed tomography (CT) or magnetic resonance (MR) is complicated by the need for breath holding and the injection of contrast media. These are often contraindicated in patients with liver failure, and we examined the ability of unenhanced 3-dimensional (3-D) navigator-echo-based MR (NE-MR) to accurately image livers and measure volumes without breath holding compared to unenhanced (plain) or gadolinium-diethylene triamine pentaacetic acid enhanced MR (Gd-MR) in miniature swine (n = 8). Without breath holding, diaphragm movement monitoring with NE-MR reduced motion artifacts in hepatic images compared with the other modalities. Without the injection of contrast media, the signal-to-noise ratios of the images obtained using NE-MR were significantly higher than those from plain MR; Gd-MR was superior to NE-MR, however (79.5 +/- 7.5 vs. 63.2 +/- 6.0 or 97.8 +/- 8.1, respectively; P < 0.01 for each). Overall, NE-MR produced improved high-resolution liver images. Consequently, liver volumes calculated based on NE-MR images were more highly correlated with actual liver weights compared to plain or Gd-MR in the whole livers (n = 8; r = 0.937 vs. 0.835 or 0.904, respectively). Also, NE-MR demonstrated significantly strong correlation between actual weights and volumetry-calculated volumes in regenerative livers 7 days after massive hepatectomy (n = 10, r = 0.989, P < 0.01). In conclusion, our results indicate that without breath holding or the injection of contrast media, 3-D NE-MR can provide both high-resolution liver images and precise hepatic volumes in patients with liver failure due to liver surgery (massive hepatectomy and living donor liver transplantation) or fulminant hepatic failure.  相似文献   
996.
Background: Lymphatic invasion is a risk factor for lymph node metastases in patients with gastric cancer. No studies have been reported, however, on the correlation between lymphatic invasion and lymph node metastasis in early gastric cancer invading into the submucosa.Methods: We performed a retrospective analysis of lymphatic invasion in 170 patients with early gastric cancer invading into the submucosa.Results: Lymphatic invasion was found in 76 patients. Lymphatic invasion correlated significantly with the presence of lymph node metastasis and vascular invasion (P < .05) and with the degree of cancerous submucosal involvement (P < .05). The presence of lymph node metastasis also correlated with the grade of submucosal invasion and lymphatic invasion. The 5-year survival of patients with lymphatic invasion was poorer than that of patients without lymphatic invasion (P < .05). Node-negative patients had similar survival, regardless of the presence of lymphatic invasion. All patients with severe lymphatic invasion had sm3 invasion and lymph node metastases.Conclusion: Although lymphatic invasion is the first stage of lymph node metastasis, lymphatic invasion in itself does not have clinical importance except for severe invasion in early gastric cancer. It is possible to predict lymph node metastases from the combined evaluation of degree of lymphatic invasion and submucosal involvement of the tumor in patients with early gastric cancer invading into the submucosa.  相似文献   
997.
Management of infected aortic aneurysms, which can be life-threatening, remains challenging. Open surgical treatments, including debridement of the infected aorta and the surrounding tissue and either in situ reconstruction or extra-anatomic bypass covering with omentum or muscle flap, are the mainstay of therapy. However, increasing advances in technology have made endovascular treatment of infected aneurysms feasible. The present study describes the first clinical report of successful treatment of an infected aneurysm using endovascular techniques in the acute phase, followed by delayed open surgery.  相似文献   
998.
We hereby present our technique for using the self-retaining flexible arm retractor and its attachments for mitral valve exposure. The Aortic Valve Assistant, which was developed for aortic valve exposure, is also very useful for exposure of the inferior wall of the left atrium. Our modified atrial hook provides excellent exposure of the anterior mitral annulus. Extensive dissection and the combined use of the flexible arm and attachments allows us comfortable access for mitral valve operations.  相似文献   
999.
Objectives: Ischemic mitral regurgitation results from annular dilatation, leaflet tethering and leaflet flattening. Undersized annuloplasty corrects annular dilatation but worsens leaflet tethering and flattening. This exacerbation of abnormal leaflet geometry may contribute to poor repair results for ischemic mitral regurgitation (IMR). Using a sheep model of IMR, we hypothesized that posterior leaflet augmentation and less-extreme annular undersizing would relieve tethering and increase leaflet curvature. Methods: Eight weeks after posterolateral infarct, 10 sheep with ≥2+ IMR underwent either a 24-mm planar ring annuloplasty (n = 5) or a 30-mm planar ring annuloplasty with concomitant posterior leaflet augmentation (n = 5). Real-time three-dimensional echocardiography allowed measurement of indices of leaflet curvature and tethering before and after annuloplasty. Results: Comparing pre- and post-repair values in the P1, P2, and P3 leaflet regions, undersized 24-mm ring annuloplasty made no significant difference to mean septolateral curvature (0.23–0.26, 0.33–0.29, and 0.27–0.37 cm−1, respectively), whereas leaflet augmentation in combination with a 30-mm ring annuloplasty increased septolateral curvature (P1 0.30–1.02, P2 0.31–1.23, and P3 0.35–0.84 cm−1, p-values < 0.05). The mean tethering angle formed between the annular plane and the posterior leaflet increased in all three posterior regions for the 24-mm ring group (P1 12–23°, P2 26–31°, and P3 16–25°), but decreased in all regions for the group undergoing leaflet augmentation (P1 +5 to −6°, P2 +13 to −13°, P3 +16-15°, all p-values < 0.05). Conclusions: Undersized annuloplasty exacerbates leaflet tethering. Posterior leaflet augmentation with less severe annular reduction increases leaflet curvature and decreases tethering; this technique more completely addresses the pathogenic mechanism of IMR and may improve repair durability.  相似文献   
1000.
The sentinel node (SN) is regarded as the first drainage lymph node, and tumor cells are considered likely to directly affect the SN. However, few reports have identified differences between SNs and non-SNs in cancer patients. Subjects in this study included 27 patients with gastric cancer who underwent curative operation and intraoperative detection of SNs by radioisotope methods. The mean number of SNs was 3.2 (range 1 to 5). Degree of infiltration of natural killer cells, dendritic cells, MIB-1 labeling index, and CD3-ξ expression of lymphocytes in SNs and non-SNs were examined by means of immunohistochemical methods. Degree of infiltration was compared according to depth of invasion and between SNs and non-SNs. Patients with early-stage cancer displayed a greater degree of infiltration of MIB-1 labeling index and CD3-ξ expression than patients with pT2 or pT3 lesions (P<0.05). The MIB-1 labeling index in SNs was significantly lower than that in non-SNs (P<0.05). However, no significant difference was observed in infiltration of natural killer cells, dendritic cells, or CD3-ξ. Morphologic changes of dendritic cells in SNs were not definite. Our results suggest that SNs in gastric cancer might not be suppressed, unlike in breast cancer and melanoma. SN paralysis may depend on tumor- and organ-specific characteristics or exogenous stimulation from the gastric mucosa. Studies in progress will help to identify immunologic paralysis of the SN in various types of cancer. Attention must therefore be paid to organ specificity.  相似文献   
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