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11.
The magnetic resonance phase-contrast technique for the measurement of flow velocity and volume in true and false lumens was studied in six patients with chronic dissecting aneurysms. Phase-contrast images were obtained at a level perpendicular to the dissecting aneurysms of the descending aorta. As the maximum diameter of aneurysms increased, the ratio of the cross-sectional area of the false to the true lumen increased and the peak average velocity in the true lumen during systole was decreased. This technique proved invaluable for determining prognosis and operability for this condition.  相似文献   
12.

Background

Pancreatic cancer is an aggressive malignancy with one of the worst mortality rates of all cancers. Recently, collapsin response mediator proteins (CRMPs) were reported to be associated with proliferation, apoptosis, differentiation, and invasion in several cancers. However, CRMP expression and their role in pancreatic cancer have not been investigated. This study aimed to clarify the clinical significance of CRMPs in pancreatic cancer.

Methods

Expression of crmp genes in 11 pairs of pancreatic cancer and corresponding noncancerous pancreas tissues were examined by real-time RT-PCR. Knockdown of CRMP4 expression using siRNA was examined in pancreatic cancer cell lines to determine whether CRMP4 regulates cell proliferation and invasion in vitro. Furthermore, CRMP4 protein levels in primary tumors of pancreatic cancer (n = 53) were examined by immunohistochemistry and compared with the clinicopathological features of the tumors.

Results

Of all the CRMPs, only CRMP4 was differentially expressed in pancreatic cancer tissues (p = 0.008). CRMP4 knockdown using siRNA reduced cellular invasion, but did not affect proliferation. The expression of CRMP4 was detected immunohistochemically in 34 (64.2 %) of the 53 pancreatic cancer samples, and CRMP4 expression was correlated with severe venous invasion (p = 0.044), stage (p = 0.019), and liver metastasis (p = 0.021). Multivariate analyses suggested that venous invasion and CRMP4 overexpression were prognostic factors for survival.

Conclusions

Our results suggested that CRMP4 is significantly associated with poor prognosis by promoting liver metastasis and can serve as a novel therapeutic target for pancreatic cancer.
  相似文献   
13.
Extensive evidence shows that a core neurobiological mechanism of autism spectrum disorder (ASD) involves aberrant neural connectivity. Recent advances in the investigation of brain signal variability have yielded important information about neural network mechanisms. That information has been applied fruitfully to the assessment of aging and mental disorders. Multiscale entropy (MSE) analysis can characterize the complexity inherent in brain signal dynamics over multiple temporal scales in the dynamics of neural networks. For this investigation, we sought to characterize the magnetoencephalography (MEG) signal variability during free watching of videos without sound using MSE in 43 children with ASD and 72 typically developing controls (TD), emphasizing early childhood to older childhood: a critical period of neural network maturation. Results revealed an age‐related increase of brain signal variability in a specific timescale in TD children, whereas atypical age‐related alteration was observed in the ASD group. Additionally, enhanced brain signal variability was observed in children with ASD, and was confirmed particularly for younger children. In the ASD group, symptom severity was associated region‐specifically and timescale‐specifically with reduced brain signal variability. These results agree well with a recently reported theory of increased brain signal variability during development and aberrant neural connectivity in ASD, especially during early childhood. Results of this study suggest that MSE analytic method might serve as a useful approach for characterizing neurophysiological mechanisms of typical‐developing and its alterations in ASD through the detection of MEG signal variability at multiple timescales. Hum Brain Mapp 37:1038–1050, 2016. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc .  相似文献   
14.

Background

The aim of this study was to clarify the technical feasibility and oncological efficacy of laparoscopy-assisted gastrectomy (LAG) for gastric cancer compared with open gastrectomy (OG).

Methods

Between April 2002 and March 2008, a series of 623 patients with gastric cancer underwent R0 gastrectomy (314 LAG patients and 309 OG patients). Age, gender, lymph node dissection, and pathological stage were matched by propensity scoring, and 212 patients (106 LAG and 106 OG) were selected for analysis after the exclusion of 40 patients who had proximal gastrectomy. Intraoperative factors, postoperative morbidity, long-term quality of life (QOL), and survival were evaluated. Moreover, these outcomes were also compared between the laparoscopy-assisted total gastrectomy (LATG) and the open total gastrectomy (OTG).

Results

There was no significant difference in preoperative characteristics between the two patient groups. Regarding intraoperative characteristics, blood loss was significantly lower in the LAG group (143?ml) than in the OG group (288?ml), while operation time was significantly longer in the LAG group (273?min) than the OG group (231?min). The degree of lymph node dissection and number of retrieved lymph nodes did not differ between the two groups. There were no significant differences in postoperative courses or overall and disease-specific survival (89.8% vs. 83.6%, P?=?0.0886; 100% vs. 95.2%, P?=?0.1073) except time to first flatus and time to use of nonsteroidal anti-inflammatory derivatives between the two groups. Significantly fewer patients felt wound pain in the LAG group 1?year after surgery. Analyses between the LATG and OTG groups showed similar results.

Conclusions

LAG for gastric cancer may be both feasible and safe. However, it will be necessary to conduct a well-designed randomized controlled trial comparing short-term and long-term outcomes between LAG and OG in a larger number of patients.  相似文献   
15.
Le Fort distraction osteogenesis is sometimes applied to improve the facial appearance in craniofacial dysostosis or cleft lip and palate. Distraction devices are generally classified into external and internal types. The movement of external distractors can be controlled easily but their large size and the need for a facial mask cause much psychological stress to the patient. Internal distractors are smaller and better tolerated, but they are not easily controllable and removal is difficult. We designed an internal distraction device to eliminate the problems of the currently available distractors -Nakajima's angle-variable internal distraction (NAVID) system - and aimed to assess its clinical applicability. Between 2000 and 2010, we treated 16 patients with the NAVID system: Le Fort I, III, III?+?I and IV distractions were performed in three, five, four and four patients, respectively. Distraction was started after a 1-week latency period. Then, the exposed rod was cut, and the distractors were left in place for 3 months or more as retention devices, and thereafter removed. All patients showed satisfactory occlusion and facial aesthetics. Open bite during the consolidation period was the main complication. In conclusion, the NAVID system is safe, effective and reliable for all types of Le Fort distraction osteogenesis.  相似文献   
16.
We report what seems to be the second documented case of perineal hernia after laparoscopic abdominoperineal resection (APR) and describe its successful repair with transperineal intraperitoneal mesh. An 89-year-old woman complained of a large, painful perineal swelling 4 months after APR for rectal cancer. Computed tomography (CT) showed small intestine protruding through the pelvic floor into the perineal area. However, opening of the hernia sac revealed no intra-abdominal adhesions. An oval, 8 × 12 cm Bard Composix Kugel Patch (Davol, Cranston, RI, USA) was inserted into the intraperitoneal space and secured over the defect in the pelvic floor; then firmly attached to the pelvic wall with 16 interrupted nonabsorbable sutures. There has been no sign of hernia recurrence in 10 months of follow-up. We speculate that because laparoscopic surgery is minimally invasive, fewer postoperative adhesions in the abdominal cavity can result in the small bowel sliding more readily into the perineal area. Based on our experience, perineal hernia after laparoscopic APR can be repaired easily and effectively with a Composix Kugel Patch.  相似文献   
17.
Purpose: Postoperative vital capacity (VC) and the 6-min walking (6MW) test were used to compare the differences in impairment of the pulmonary function and walking capacity in patients undergoing a lobectomy by video-assisted thoracoscopic surgery (VATS), an anterior limited thoracotomy (ALT), an anteroaxillary thoracotomy (AAT), or a posterolateral thoracotomy without muscle sparing (PLT). Methods: The study was a retrospective analysis. Lung cancer patients who underwent a lobectomy by VATS, ALT, AAT, or PLT (28 in each group) were matched by sex and age (±5 years). VC was measured before surgery and at 1, 2, 4, 12, and 24 weeks after surgery. The distance covered during the 6MW test (6MWD) was measured before surgery and in a postoperative test 1 week after surgery. Results: Compared with the VATS, ALT, and AAT groups, PLT patients showed a significant impairment of VC from 1 to 24 weeks after surgery (P < 0.05–0.001) and also a significant impairment of 6MWD 1 week after surgery (P < 0.01–0.001). The AAT group showed a significant impairment of 6MWD 1 week after surgery compared with the VATS and ALT groups (P < 0.001 and P < 0.05, respectively). There was no significant difference in the impairment of either VC or 6MWD between VATS and ALT. Conclusions: The PLT without a muscle sparing procedure therefore cannot be recommended for general lung cancer surgery because of the impairment of both walking capacity and pulmonary function which continues long after surgery. VATS and ALT are better procedures than AAT regarding the recovery of walking capacity early after surgery. VATS and ALT are similar to each other regarding the impairment of pulmonary function and walking capacity after surgery. Received: October 15, 2001 / Accepted: July 2, 2002 Reprint requests to: H. Nomori  相似文献   
18.
BACKGROUND: To test the reliability of sentinel lymph node identification in non-small cell lung cancer, sentinel nodes were localized with a radioactive colloid in patients undergoing surgery. METHODS: Forty-six patients with non-small cell lung cancer undergoing curative resection with mediastinal lymph node dissection were examined. The day before surgery, technetium-99m ((99m)Tc) tin colloid was injected into the peritumoral region. At operation, the radioactivity of the lymph nodes was counted with a handheld gamma counter before (in vivo) and after (ex vivo) dissection. Lymph nodes with an ex vivo radioactive count more than 10 times the background value were identified as sentinel nodes. The correlation between the in vivo and ex vivo results was examined. RESULTS: Lymphoscintigraphy revealed that it took longer than 6 hours for sufficient (99m)Tc tin colloid to reach the sentinel nodes. Sentinel nodes could be identified in 40 patients (87%). Patients whose sentinel nodes could not be identified had a significantly lower ratio of forced expiratory volume in 1 second to forced vital capacity than did those with identifiable sentinel nodes (P =.03). No false-negative sentinel nodes were detected in 14 patients with N1 or N2 disease (0%). In the hilar lymph node stations, the lobar lymph nodes were most frequently identified as sentinel nodes (as often as 85% of the time). Fourteen patients (35%) had sentinel nodes in the mediastinum, the distribution of which depended on the lobe. In vivo and ex vivo counting showed 88% concurrence for the identification of sentinel nodes in mediastinal lymph node stations. CONCLUSION: The identification of sentinel nodes with (99m)Tc tin colloid is a reliable method of establishing the first site of nodal metastasis in non- small cell lung cancer. Sentinel nodes could be hardly identified in patients with a low ratio of forced expiratory volume in 1 second to forced vital capacity because of such conditions as chronic obstructive pulmonary disease. In vivo identification of sentinel nodes in the mediastinum could be useful approach to guide mediastinal lymph node sampling or dissection.  相似文献   
19.
Laparoscopic restorative proctocolectomy for patients with ulcerative colitis   总被引:11,自引:0,他引:11  
BACKGROUND: Significant concern continues about the feasibility of laparoscopic restorative proctocolectomy (RP) with an ileal J pouch anal anastomosis in the surgical treatment of patients with ulcerative colitis (UC). The aim of this study was to clarify the feasibility of laparoscopic RP at a single institution where the surgical routine of laparoscopic colorectal surgery has already been established. PATIENTS AND METHODS: Between July 1994 and December 2001, 18 patients with UC underwent laparoscopic RP. The median age was 30 (range, 18-51) years, and the median follow-up was 20 (range, 5-89) months. Five trocars were placed. After the entire colon and rectum were mobilized and the vessels were divided intracorporeally, the rectum was divided with use of a laparoscopic linear stapler. A pouch anal anastomosis was fashioned with use of a double stapling technique. A diverting loop ileostomy was fashioned. RESULTS: There were no conversions to the open procedure. The median operative time and median blood loss were 360 (range, 290-500) minutes and 105 (range, 10-586) mL, respectively. Six postoperative complications occurred (wound sepsis, 2; bowel obstruction, 1; anastomotic stricture, 2; pouchitis, 1). In one patient, a bowel obstruction developed 3 months after the operation, which was managed conservatively. The median length of the hospital stay was 9 (range, 7-21) days. CONCLUSIONS: The laparoscopic RP is safe and feasible in selected patients with UC. New laparoscopic instrumentation, such as a linear stapler, and a more reliable laparoscopic coagulating and dividing tool should be designed, which would make it possible to perform this procedure more frequently in the surgical treatment of UC.  相似文献   
20.
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