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51.
Treatment of prostate cancer utilizing iodine 125 (125I) interstitial seed implants has become an accepted and widely used modality. Numerous variations in 125I seed implant loading distribution techniques have developed as a result of the preferences of individual institutions implementing the modality. No particular universal standard is currently used for 125I seed implants. A major concern with 125I seed implants is coverage of the prostate with the desired dose and the minimization of dose to the urethra. A variation of seed distribution per individual anatomy is desirable. Historically, brachytherapy relied on dosimetry systems, such as the Paris, Quimby, and Manchester systems to achieve the desired dose distribution. Use of various peripherally loaded 125I seed implant distributions to accommodate anatomic variations within the same institution prompted the interest of how the results compare to the Manchester system.  相似文献   
52.
BACKGROUND: For cyclosporine (CsA), 2-hr postdose level (C2) is the best single time point predictor of the area under the curve and a critical measure for effective dosing. The therapeutic CsA microemulsion (Neoral) C2 range in de novo heart transplant patients remains to be determined. PURPOSE: The purpose of this study was to determine the efficacy of CsA C2 monitoring in de novo heart transplant patients receiving basiliximab induction. METHODS: This prospective, multicenter, randomized study enrolled 87 adult heart transplant recipients stratified according to 4 to 6 hrs posttransplant serum creatinine less than or equal to 170 micromol/L (cohort A) or more than 170 micromol/L (cohort B). Patients in cohort A were randomized into three C2 ranges (A1: "high" n=25, 1600-1800 ng/mL; A2: "intermediate" n=27, 1400-1600 ng/mL; and A3: "low" n=24, 1200-1400 ng/mL). Patients in cohort B were randomized into intermediate (n=5) and low C2 (n=6). Target ranges were progressively lowered after 1 month. Immunosuppression included basiliximab, Neoral, mycophenolate mofetil, and corticosteroids. Endpoints were acute rejection and renal function. RESULTS: The incidence of acute rejection at 12 months was 44% in group A1, 41% in group A2, 33% in group A3, and 27% in cohort B. Pretransplant and 12-month creatinine clearance (mL/min) were group A1, 72+/-25 and 64+/-24; group A2, 81+/-32 and 68+/-25; group A3, 91+/-28 and 86+/-26; and cohort B, 62+/-28 and 79+/-37. CONCLUSION: These results suggest that C2 monitoring is safe in de novo heart transplant patients. A low Neoral C2 range in combination with basiliximab induction resulted in preserved renal function without increased risk of acute rejection.  相似文献   
53.
Objective The objective of the study was to determine the outcomes for primary gastrointestinal melanomas (PGIM). Material and methods The Surveillance, Epidemiology, and End Results database (1973–2004) was queried. Results Overall, 659 cases of PGIM were identified. The annual incidence of PGIM was approximately 0.47 cases per million in 2000. Overall median survival time was 17 months. Tumors were identified in the oral–nasopharynx (32.8%), anal canal (31.4%), rectum (22.2%), esophagus (5.9%), stomach (2.7%), small bowel (2.3%), gallbladder (1.4%), and large bowel (0.9%). Univariate analysis demonstrated age, tumor location, stage, surgery, and lymph node status were significant predictors of improved survival. MST has not been reached for tumors located in the large bowel, while tumors located in the stomach demonstrated the shortest median survival (5 months). Improvement in MST was observed for those patients undergoing surgical resection. The presence of lymph node involvement conferred a poorer prognosis. Multivariate analysis of the cohort identified that location, advanced tumor stage, failure to undertake surgical resection, positive lymph node status, and age were all independent predictors of poorer outcome. Conclusion PGIM occurs most often in the oral–nasopharynx and anal canal. Surgical extirpation is the only identifiable treatment modality that significantly improves survival.  相似文献   
54.
PURPOSE: Video endoscopic inguinal lymphadenectomy is a recently described lymphadenectomy with the same template of the open technique but performed with laparoscopic instruments under video guidance. It was developed to decrease procedure related morbidity while maintaining good oncological results. We report our initial results in a trial comparing video endoscopic inguinal lymphadenectomy with standard inguinal lymphadenectomy. MATERIALS AND METHODS: From 2003 to 2005, 10 patients with penile carcinoma who were at high risk for inguinal metastases underwent bilateral inguinal lymphadenectomy. We performed standard lymphadenectomy in 1 limb and video endoscopic inguinal lymphadenectomy on the contralateral side. Perioperative results and followup data were compared. RESULTS: No intraoperative complications occurred. Mean operative time was 92 and 126 minutes for open and endoscopic surgery, respectively (p=0.00002). Despite the small number of patients we noted a decrease in cutaneous complications with video endoscopic inguinal lymphadenectomy (0% vs 50%, p=0.017) and a trend toward decreased overall morbidity with this endoscopic technique (20% vs 70%, p=0.059). The mean number of retrieved and positive lymph nodes were similar for the 2 techniques. At a mean followup of 18.7 months (range 12 to 31) no signs of recurrence or disease progression were noted. In the postoperative period 9 of the 10 patients identified video endoscopic inguinal lymphadenectomy as the preferred technique in terms of surgical morbidity. CONCLUSIONS: Video endoscopic inguinal lymphadenectomy is a safe and feasible technique in patients with penile carcinoma and nonpalpable nodes. These preliminary results suggest that video endoscopic inguinal lymphadenectomy may decrease postoperative morbidity without compromising oncological control. Future studies should include the bilateral procedure, longer term followup and a greater number of patients.  相似文献   
55.
This study examines the responsiveness of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Short Form-36 (SF-36) in patients undergoing total hip arthroplasty. Eighty-nine patients completed the WOMAC and SF-36 preoperatively and postoperatively. Standardized response means (SRMs) and effect sizes (ES) were used to measure responsiveness. Mean follow-up was 17 months. The SRMs for the WOMAC ranged from -0.93 to -1.49, and the ES ranged from -1.02 to -1.53. The SRMs for the SF-36 ranged from 0.22 to 1.64, and the ES ranged from 0.20 to 1.97. The highest values occurred with the physical functioning, bodily pain, and Physical Component Summary Scales. This study demonstrates a similar level of responsiveness of the WOMAC and several components of the SF-36. This suggests that the isolated use of the SF-36 may be adequate to monitor outcomes after total hip arthroplasty. There may still be a role for the WOMAC when comparing outcomes of specific designs or techniques of total hip arthroplasty.  相似文献   
56.
Distraction osteogenesis for the cleft lip and palate patient   总被引:1,自引:0,他引:1  
Gradual maxillary distraction by modified osteotomies and external force systems is a procedure with minimal morbidity and few complications. The interaction between surgeons and orthodontists is critical, however. The wide range of possibilities for remodeling a hypoplastic maxilla by distraction allows the potential to simultaneously advance and to elongate the midface, thereby restructuring the skeletal framework with mature new bone. An expansion of all the soft tissues of the face and palate (muscles, nerves, vessels, mucosa, skin) occurs in conjunction with bone elongation. This process ultimately produces excellent functional and aesthetic results in patients with midface deficiency, thus restoring their facial appearance and avoiding many years of facial deformity and associated psychologic sequelae.  相似文献   
57.
Motion artifact simulating aortic dissection on CT   总被引:3,自引:0,他引:3  
We recently imaged two patients clinically suspected of having aortic dissection whose contrast-enhanced CT examinations, obtained on a new scanner with a 1-sec scanning time, showed findings suggesting an ascending aortic dissection. The subsequent clinical course and evaluation implied that the CT findings were predominantly artifactual. We identified identical artifacts in 18% of 50 consecutive contrast-enhanced CT examinations performed for a variety of indications on the same scanner. The double-lumen artifact, simulating an intimal flap, occurs in the proximal ascending aorta and is limited to one or two contiguous transaxial images. The artifact was not detected on two other CT units. We believe the artifact arises from motion of the aortic wall and the surrounding pericardial recesses during image acquisition.  相似文献   
58.
OBJECTIVE: We evaluated the incidence and organ distribution of arterial extravasation identified using contrast-enhanced helical CT in patients who had sustained abdominal visceral injuries and pelvic fractures after blunt trauma. SUBJECTS AND METHODS: Five hundred sixty-five consecutive patients from four level I trauma centers who had CT scans showing abdominal visceral injuries or pelvic fractures were included in this series. The presence or absence of arterial extravasation, as well as the anatomic sites of arterial extravasation, was noted. We obtained clinical follow-up data, including surgical or angiographic findings. RESULTS: In our series, 104 (18.4%) of 565 patients had arterial extravasation. Of the 104 patients, 81 (77.9%) underwent surgery, embolization, or both. The combined rate of surgery or embolization in patients with arterial extravasation was statistically higher than expected at all four institutions (p <0.001). The spleen was the most common organ injured, occurring in 277 (49.0%) of 565 patients, and arterial extravasation occurred in 49 (17.7%) of 277 patients with splenic injury. Several other visceral injuries were associated with arterial extravasation, including hepatic, renal, adrenal, and mesenteric injuries. CONCLUSION: Based on the limited reports of arterial extravasation in the nonhelical CT literature, the percentage (18%) of clinically stable patients in our study with CT scans showing arterial extravasation was higher than anticipated. This finding likely reflects the improved diagnostic capability of helical CT. Although the spleen and liver were the organs most commonly associated with arterial extravasation, radiologists should be aware that arterial extravasation may be associated with several other visceral injuries.  相似文献   
59.
60.

Background

Studies to identify preoperative prognostic variables for pancreatic neuroendocrine tumor (PNET) have been inconclusive. Specifically, the prevalence and prognostic significance of radiographic calcifications in these tumors remains unclear.

Methods

From 1998 to 2009, a total of 110 patients with well-differentiated PNET underwent surgical resection at our institution. Synchronous liver metastases present in 31 patients (28%) were addressed surgically with curative intent. Patients with high-grade PNET were excluded. The presence of calcifications in the primary tumor on preoperative computed tomography was recorded and correlated with clinicopathologic variables and overall survival.

Results

Calcifications were present in 16% of patients and were more common in gastrinomas and glucagonomas (50%), but never encountered in insulinomas. Calcified tumors were larger (median size 4.5 vs. 2.3?cm, P?=?0.04) and more commonly associated with lymph node metastasis (75 vs. 35%, P?=?0.01), synchronous liver metastasis (62 vs. 21%, P?P?P?=?0.01) and size (P?P?=?0.04), but not in the presence of radiographic calcifications.

Conclusions

Calcifications on preoperative computed tomography correlate with intermediate grade and lymph node metastasis in well-differentiated PNET. This information is available preoperatively and supports the routine dissection of regional lymph nodes through formal pancreatectomy rather than enucleation in calcified PNET.  相似文献   
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