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51.

Objectives:

To compare the mean total antioxidant status (TAS) among 3 glaucoma types, namely: pseudoexfoliation glaucoma (PEG), primary open angle glaucoma (POAG), and primary angle closure glaucoma (PACG), and study its potential association with various clinical glaucoma-parameters.

Methods:

In this case-control study, plasma samples were obtained between September 2013 and October 2014 from 340 glaucoma patients (PEG [n=54]; POAG [n=147]; PACG [n=139]), and 351 controls of matching age, gender, ethnicity, and 5 different systemic co-morbidities from King Abdulaziz University Hospital, Riyadh, Saudi Arabia. The TAS in all samples was determined by a colorimetric-based assay.

Results:

The mean±standard deviation of TAS was significantly lower among cases: 0.77±0.32 than controls: 1.1±0.22, p<0.0001. Moreover, the TAS levels were significantly different across the 3 types of glaucoma: 0.86±0.24 in PEG, 0.47±0.32 in POAG, and 0.98±0.41 in PACG (all p<0.0001). In addition, there was a significant correlation between TAS and age at onset (Pearson correlation coefficient [R] 0.17, p<0.0001), cup/disc ratio (R: -0.13, p=0.004), and number of anti-glaucoma medications (R: -0.16, p=0.001).

Conclusion:

Our findings provide evidence that plasma TAS levels are decreased in patients with glaucoma, more so in POAG and PEG than PACG, supporting the hypothesis that decreased antioxidative defense and/or increased oxidative stress may have a critical role in the pathogenesis of glaucoma.Glaucoma is a progressive optic neuropathy associated with optic nerve damage, and is one of the most leading cause of blindness worldwide.1 Elevated intraocular pressure (IOP) as a result of reduction in normal aqueous outflow is a major causal risk factor that is well supported by animal studies.2-4 Although IOP is considered a major risk factor for glaucoma,2,3 other concomitant factors affecting the pathophysiology of glaucomatous retinal ganglion cell (RGC) death include retinal ischemia,5 nutritional status,6 and oxidative stress.7 There is evidence of oxidative damage in ocular diseases, such as cataract and age-related macular degeneration.8 In addition, significant oxidative damage has been demonstrated in human trabecular meshwork (TM) cells of patients with glaucoma,7 causing elevated IOP and visual field damage.9 Furthermore, our previous studies have documented mitochondrial abnormalities10-12 (oxidative stress marker), and glutathione-S-transferase (antioxidant) gene (GST) polymorphisms to be associated with various types of glaucoma.13 It is clearly evident from the literature, and our own studies, that oxidative stress mechanisms play a critical role in the pathogenesis of glaucoma. Previous studies had demonstrated reduced total antioxidant capacity in aqueous humor and blood samples from patients with glaucoma.14-17 To evaluate the role of oxidative stress in different types of glaucoma we had previously investigated total antioxidants status (TAS) in the plasma of pseudoexfoliation glaucoma (PEG) patients,18 primary angle closure glaucoma (PACG) patients,19 and in the plasma of primary open angle glaucoma (POAG) patients.20 As an extension to these studies, here, we compare the mean TAS level among these 3 glaucoma types, and study the potential association between the TAS level and various clinical parameters important to each type of glaucoma.18-20  相似文献   
52.

OBJECTIVE

To asses the efficacy and safety of bidirectional synchronous twin‐pulse extracorporeal shock wave lithotripsy (ESWL) compared with standard ESWL.

PATIENTS AND METHODS

Between March 2003 and December 2006, 240 patients with a radio‐opaque single renal stone of ≤25 mm were randomized to treatment either by the Twinheads (TH) lithotripter (FMD, Lorton, Virginia, USA) or the Dornier Lithotripter S (DLS, Dornier MedTech Europe GmbH, Germering, Germany). Before and after ESWL, urinary N‐acetyl‐B‐glucosaminidase (NAG) levels were assessed and patients were evaluated with dynamic MRI. The efficacy and complications were compared, with success defined as no residual fragments.

RESULTS

For stones of >10 mm the rate for the failure of disintegration was 13.3% for the DLS vs 1.4% for the TH (P = 0.009). For stones of ≤10 mm the stone‐free rate was 74.4% for the TH vs 67.7% for the DLS (P = 0.6), while for stones of >10 mm it was 78.1% and 66.7%, respectively (P = 0.14). The median (range) number of sessions in both groups was 2 (1–5). After ESWL urinary NAG levels were increased significantly in both groups; in the TH group it declined below the level before ESWL after 2 days, while in the DLS group it remained high after 7 days. In the DLS group four patients developed subcapsular or parenchymal haematoma after ESWL, vs none in the TH group. There was loss of corticomedullary differentiation after ESWL in three patients in the DLS group and only one in the TH group. In the DLS group there was a statistically significantly decrease in bilateral renal perfusion after ESWL, but no changes in the TH group.

CONCLUSIONS

Synchronous twin‐pulse ESWL has clinical advantages over standard ESWL in terms of safety and efficacy.  相似文献   
53.
Direct vascular injury after primary total knee arthroplasty is rare. This case report illustrates a 65-year-old female who was diagnosed with a pseudoaneurysm of the popliteal artery when she was investigated for increased leg swelling and pain 1 week after total knee arthroplasty. She had a percutaneous endovascular repair with a stent after thrombectomy.  相似文献   
54.
PURPOSE: We describe a novel technique of extraperitoneal laparoscopic trigonoplasty for the treatment of vesicoureteral reflux. MATERIALS AND METHODS: Three boys and 24 girls with 41 refluxing units underwent extraperitoneal laparoscopic trigonoplasty. A 10 mm incision was made below the umbilicus. With sharp, blunt finger dissection and balloon dilation an extraperitoneal space was created. The bladder was opened using a laparoscopic scissors. Two 3Fr ureteral catheters were inserted intracorporeally into the ureters. A transverse superficial incision was made in the epithelium between the ureteral orifices. The medial aspect of the ureters was cleared of the muscles and attachments, and sutured in the midline with 4-zero polyglactin sutures. RESULTS: Operative time ranged from 60 to 240 minutes (mean 147). Blood loss was less than 50 ml. Adequate extraperitoneal space, bladder opening, epithelial incision, ureteral approximation with secure suturing in the midline and bladder closure were carried out in all cases. Peritoneal perforation was noted in 4 patients while creating the extraperitoneal space, with suturing needed for 1 large perforation. Hospital stay was 1 to 6 days (mean 2.7). At 4 to 19 months of followup (mean 8.2) reflux had resolved in 38 units (93%). CONCLUSIONS: Extraperitoneal laparoscopic trigonoplasty is technically feasible. Results are comparable to open techniques. The major advantage of this procedure is the avoidance of peritoneum. Other advantages include a shorter hospital stay and good cosmesis. More followup is necessary to establish the long-term results.  相似文献   
55.
56.
57.
Study Type – Diagnostic (exploratory cohort)
Level of Evidence 2b

OBJECTIVE

To develop a nomogram to predict the probability that the pathological Gleason sum (GS) will be higher than that indicated by the biopsy, suggesting a higher risk for the patient presumed to be at low risk, as a substantial proportion of patients with low and intermediate grade on biopsy are upgraded on interpretation of the radical prostatectomy (RP) specimens, but a similar clarification of accurate Gleason scoring is not available in patients with no surgical histology.

PATIENTS AND METHODS

The study included 1017 patients who had RP after biopsy showing GS 6 and 7 (3 + 4) from 2000 to 2007. Nomogram predictor variables included age, race, digital rectal examination, prostate‐specific antigen (PSA) level, number of cores taken, number of positive cores, maximum percentage cancer in any core, number of previous biopsies, prostate volume, clinical stage, high‐grade prostatic intraepithelial neoplasia, atypical small acinar proliferation, inflammation and perineural invasion. We calculated the nomogram‐predicted probability in each patient. The area under the receiver operating characteristic curve was calculated as a measure of discrimination, and the calibration was assessed graphically.

RESULTS

The mean age of the patients was 60 years, the mean PSA level 6.62 ng/mL; 336 patients were upgraded (33%), 623 remained the same (61.3%) and 58 were downgraded (5.7%). A nomogram for predicting the possibility of upgrading was constructed that had a concordance index of 0.68. The nomogram was well calibrated.

CONCLUSIONS

Our nomogram for predicting upgrading provides important additional information for deciding on treatment to both the urologist and the patient with low‐ and intermediate‐grade prostate cancer. It might prove useful when the possibility of a more aggressive Gleason variant can change the management, and is especially meaningful when management options other than surgery are selected based on the inability to recognize the true pathological actual GS.  相似文献   
58.
Tears in the gluteus medius and minimus tendons, often misdiagnosed as trochanteric bursitis, have recently emerged as an important cause of recalcitrant greater trochanter pain syndrome. Advances in endoscopic surgery of the hip have created opportunities to better evaluate and treat pathology in the peritrochanteric compartment. We reviewed the literature on trochanteric pain syndrome and gluteus medius tendon injuries. Existing techniques for endoscopic and open gluteus tendon repair and potential challenges in restoration of abductor function were analyzed. Partial-thickness undersurface tears of the gluteus medius were identified as a common pathologic entity. Although these tears are otherwise analogous to partial-thickness tears of the rotator cuff, the lack of arthroscopic access to the deep side of the gluteus medius tendon represents a unique technical challenge. To address the difficulty in visualizing and thus repairing undersurface tears of the gluteus medius, a novel endoscopic trans-tendinous repair technique was developed. The purposes of this article are to review the anatomy, pathology, and existing repair techniques of gluteus medius tendon tears and to describe the rationale and surgical steps for endoscopic trans-tendinous repair.  相似文献   
59.
Patellofemoral pain, crepitus, and locking are infrequent symptoms after total knee arthroplasty (TKA). We performed a retrospective review of 25 patients who underwent arthroscopic debridement after primary TKA to treat the patellar clunk syndrome (15 knees) or patellofemoral synovial hyperplasia (10 knees). After surgery, patient-reported knee pain and crepitus as well as Knee Society knee and function scores improved in both groups. Postoperative knee range of motion remained unchanged. Arthroscopic debridement of symptomatic patellofemoral synovium after TKA is a safe and effective procedure.  相似文献   
60.
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