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81.

Background

Unplanned re-exploration of the craniotomy after surgical treatment of unruptured intracranial aneurysms (UIAs) is sometimes required, but the underlying causes and rates of these procedures are seldom reported. This study retrospectively analyzed the causes of such re-explorations to identify methods for decreasing their necessity.

Method

From January 2000 to December 2011, 1,720 patients with a total of 1,938 UIAs underwent surgical treatment at our institution. From this cohort, 26 patients (1.5 %) with 38 UIAs required re-exploration. Clinical data, aneurysm characteristics, treatment methods, and the incidence and causes of re-exploration of the craniotomy were analyzed for these 26 patients.

Results

Several causes of re-exploration were identified: compromised distal blood flow (eight patients, 0.47 %), hemorrhagic venous infarction (four patients, 0.23 %), brain retraction injury (three patients, 0.17 %), newly identified aneurysms (three patients, 0.17 %), bleeding from an incompletely clipped aneurysm (two patients, 0.12 %), epidural hematoma (two patients, 0.12 %), failed aneurysm clipping (two patients, 0.12 %) and other causes (two patients, 0.12 %). Annual re-exploration incidence rates ranged from 0 to 3.1 %. Annual incidence rates gradually decreased following the introduction of several intraoperative monitoring systems.

Conclusions

Precise surgical planning and careful operative techniques can reduce the incidence of unplanned re-exploration of the craniotomy. The introduction of various intraoperative monitoring systems can also contribute to a reduction in this incidence.  相似文献   
82.

Background

The volume–outcome relationship in laparoscopic surgery is controversial. This study was designed to identify differences in laparoscopic gastrectomy outcomes between a low-volume hospital and a high-volume center and to provide guidelines for overcoming the problems associated with a low-volume hospital.

Methods

From April 2009 to November 2012, one surgeon performed 134 totally laparoscopic distal gastrectomies (TLDGs) at a high-volume center (HVC; ASAN Medical Center) and at a low-volume hospital (LVH; Hanyang University Guri Hospital). All laparoscopically assisted gastrectomies were excluded from this study. During the early period of laparoscopic gastrectomy at the low-volume hospital, TLDG with Roux-en-Y gastrojejunostomy (RYGJ) was performed according to the surgeon’s choice. The reconstruction method was classified as gastroduodenostomy (GD) or RYGJ. Early surgical outcomes achieved at the LVH were investigated and compared with those obtained at the HVC.

Results

The early surgical outcomes differed significantly between the two hospitals. In particular, the postoperative complication rate for the patients who underwent TLDG RYGJ at the LVH was higher than at the HVC (LVH 15.4 % vs. HVC 0 %; p = 0.037). Furthermore, significant differences were observed in the mean operation time (TLDG GD: LVH 141.0 min vs. HVC 117.4 min, p = 0.001; TLDG RYGJ: LVH 186.3 min vs. HVC 134.6 min, p = 0.009) and length of hospital stay (TLDG GD: LVH 8.1 days vs. HVC 7.2 days, p = 0.044; TLDG RYGJ: LVH 11.5 day vs. HVC 6.8 day, p = 0.009).

Conclusions

Although all the operations were performed by one experienced surgeon, the early surgical outcomes differed significantly between the low- and high-volume hospitals. Low-volume hospitals often lack well-trained surgical professionals such as first assistants and scrub nurses. Therefore, the authors recommend that a surgeon who works at an LVH should assess potential personnel shortages and find a solution before operating.  相似文献   
83.
Background contextThoracolumbar burst fractures have good outcomes when treated with early ambulation and orthosis (TLSO). If equally good outcomes could be achieved with early ambulation and no brace, resource utilization would be decreased, especially in developing countries where prolonged bed rest is the default option because bracing is not available or affordable.PurposeTo determine whether TLSO is equivalent to no orthosis (NO) in the treatment of acute AO Type A3 thoracolumbar burst fractures with respect to their functional outcome at 3 months.Study designA multicentre, randomized, nonblinded equivalence trial involving three Canadian tertiary spine centers. Enrollment began in 2002 and 2-year follow-up was completed in 2011.Patient sampleInclusion criteria included AO-A3 burst fractures between T11 and L3, skeletally mature and older than 60 years, 72 hours from their injury, kyphotic deformity lower than 35°, no neurologic deficit. One hundred ten patients were assessed for eligibility for the study; 14 patients were not recruited because they resided outside the country (3), refused participation (8), or were not consented before independent ambulation (3).Outcome measuresRoland Morris Disability Questionnaire score (RMDQ) assessed at 3 months postinjury. The equivalence margin was set at δ=5 points.MethodsThe NO group was encouraged to ambulate immediately with bending restrictions for 8 weeks. The TLSO group ambulated when the brace was available and weaned from the brace after 8 to 10 weeks. The following competitive grants supported this work: VHHSC Interdisciplinary Research Grant, Zimmer/University of British Columbia Research Fund, and Hip Hip Hooray Research Grant. Aspen Medical provided the TLSOs used in this study. The authors have no financial or personal relationships that could inappropriately influence this work.ResultsForty-seven patients were enrolled into the TLSO group and 49 patients into the NO group. Forty-six participants per group were available for the primary outcome. The RMDQ score at 3 months postinjury was 6.8±5.4 (standard deviation [SD]) for the TLSO group and 7.7±6.0 (SD) in the NO group. The 95% confidence interval (?1.5 to 3.2) was within the predetermined margin of equivalence. Six patients required surgical stabilization, five of them before initial discharge.ConclusionsTreating these fractures using early ambulation without a brace avoids the cost and patient deconditioning associated with a brace and complications and costs associated with long-term bed rest if a TLSO or body cast is not available.  相似文献   
84.

Background:

Partial thickness rotator cuff tears occupy an important position in the spectrum of rotator cuff disease. The development of a more comprehensive classification has been sought to address both the tear location and extent, which may influence clinical results. The purpose of this study is to classify partial thickness rotator cuff tears according to the arthroscopic findings and to evaluate the clinical outcomes after arthroscopic repair of partial thickness tears.

Materials and Methods:

One hundred and two patients had arthroscopic treatment of partial thickness rotator cuff tears. The inclusion criterion for the study was a partially torn supraspinatus tendon involving articular or bursal side, verified by direct arthroscopic visualization. Outcome analysis was exclusively applied to patients who underwent transtendon repair, using the shoulder index of American Shoulder and Elbow Society and the University of California Los Angeles (UCLA) rating system.

Results:

Partial thickness rotator cuff tears were divided into five groups according to arthroscopic findings. There was significant improvement after surgery in all parameters of clinical evaluation in the tears that warranted repair. Arthroscopic repair in situ (transtendon technique) may be the preferred option in unstable partial thickness tear.

Conclusion:

The proposed classification system may assist decision making in the treatment of partial thickness rotator cuff tears.  相似文献   
85.
To effectively suppress porcine endogenous retroviruses (PERV)s, RNAi technique was utilized. RNAi is the up‐to‐date skill for gene knockdown which simultaneously multitargets both gag and pol genes critical for replication of PERVs. Previously, two of the most effective siRNAs (gag2, pol2) were found to reduce the expression of PERVs. Concurrent treatment of these two siRNAs (gag2+pol2) showed knockdown efficiency of up to 88% compared to negative control. However, despite the high initial knockdown efficiency 48 h after transfection caused by siRNA, it may only be a transient effect of suppressing PERVs. The multitargeting vector was designed, containing both gag and pol genes and making use of POL II miR Expression Vector, which allowed for persistent and multiple targeting. This is the latest shRNA system technique expressing and targeting like miRNA. Through antibiotics resistance characteristics utilizing this vector, miRNA‐transfected PK15 cells (gag2‐pol2) were selected during 10 days. An 88.1% reduction in the level of mRNA expression was found. In addition, we performed RT‐activity analysis and fluorescence in situ hybridization assay, and it demonstrated the highest knockdown efficiency in multitargeting (gag2+pol2) miRNA group. Therefore, according to the results above, gene knockdown system (siRNA and shRNA) through multitargeting strategy could effectively inhibit PERVs.  相似文献   
86.
ObjectivesLongitudinal studies report racial disparities in prostate cancer (PCa) including greater incidence, more aggressive tumor biology, and increased cancer-specific mortality in African American (AA) men. Regret concerning primary treatment selection is underevaluated in patients with PCa. We investigated the relationships between clinicopathologic variables across racial and socioeconomic lines following robotic-assisted laparoscopic prostatectomy.Materials and methodsWe assessed treatment decisional regret using a validated questionnaire in a total of 484 white and 72 AA patients with PCa who were followed up for a median of 16.6 months post–robotic-assisted laparoscopic prostatectomy. Socioeconomic status (SES) information was aggregated from 2010 US census zip code data. Perioperative clinicopathologic characteristics and functional outcomes were compared between groups. Univariate and multivariate regression analyses were used to evaluate the influence of race, aggregate SES, and other clinical and demographic characteristics on decisional regret.ResultsThe majority (87.7%) of the population was not regretful of their decision to undergo treatment. However, a greater proportion of AA vs. white patients were regretful (20.6% vs. 11.2%, respectively; P = 0.03). AA and white men were similar on all functional, clinical, and pathologic features with the exception of younger age among AA men (56 vs. 60 y, respectively; P<0.001). Although there were significant differences in SES by race (P<0.001), regret did not differ by SES (β =?1.53; P = 0.15). Race, postoperative sexual dysfunction, pad usage, and length of hospital stay, however, were significantly associated with decisional regret.ConclusionsAA men were more regretful than white men, after adjusting for clinicopathologic characteristics and postoperative functional outcomes.  相似文献   
87.

Background

Completion total gastrectomy for remnant gastric cancer (RGC) is technically challenging, especially using the minimally invasive approach. Only a few small case series have reported the technical feasibility of completion total gastrectomy by minimally invasive surgery (MIS). The aim of this study was to compare the efficacy and safety of MIS and open surgery for RGC.

Methods

We retrospectively analyzed 76 completion total gastrectomies for RGC between 2005 and 2012. Indications for MIS were limited to no evidence of serosa invasion or lymph node metastasis to extraperigastric areas on preoperative evaluation. We compared patient characteristics, intraoperative factors, post-operative outcomes, and survival for the MIS and open surgery groups.

Results

Eighteen patients underwent completion total gastrectomy with MIS (10 laparoscopic, 8 robotic) and 58 patients underwent open surgery. Operation time was longer in the MIS than the open group (266 vs. 203 min, P = 0.004), but the groups had similar estimated blood loss, frequency of unplanned other organ resection, and number of retrieved lymph nodes. The MIS group had a significantly earlier initiation of soft diet, shorter hospital stay, and fewer pain medication injections. Complication rates, recurrence, and overall 5-year survival were similar for the two groups. When we compared laparoscopy with robotic, similar result was shown in all parameters except operation time.

Conclusions

Compared to open surgery, MIS for RGC demonstrated better short-term outcome and comparable oncologic results. MIS for RGC is feasible and safe and maintains advantages of minimal invasiveness. Both laparoscopic and robotic approaches are reasonable to the management of RGC.  相似文献   
88.

Purpose

To evaluate how often manipulation under anesthesia (MUA) can achieve functional flexion ≥ 90 degrees and identify predictor for successful outcome of MUA for stiff total knee arthroplasty (TKA).

Methods

Demographic data, range of motion, and surgical and anesthetic information of 143 MUAs were retrospectively analyzed from 2000 to 2011.

Results

One-hundred thirty-six out of 143 patients (95 %) improved mean range of motion (ROM) from pre-MUA 62 ± 17° to final ROM 101 ± 21° (p < 0.001). Flexion ≥ 90 degrees was achieved in 74% (106/143) of patients. Regional anesthesia was identified as predictor of successful MUA outcome (p = 0.007, OR: 8.5, 95 % CI: 1.2-66.7).

Conclusions

Although the proportion of patients regaining flexion ≥ 90 degrees following MUA was less than those patients with simple overall ROM increase, the functional flexion ≥ 90 degrees was achieved in the vast majority of patients with stiff TKA following MUA.  相似文献   
89.
Background: Human placental extract (HPE), prepared from the placentas of healthy, postpartum females, displays various physiological activities, including antioxidative properties. In this study, a dorsal skin flap model was used to investigate the effect of HPE on flap viability in rats. Materials and methods: Forty male Sprague-Dawley rats underwent random-pattern skin flap surgeries. The animals were randomly divided among a control group and three treatment groups (localized injection (LI), 10 mg/kg/d localized HPE injections; low-dose treatment (LT), 10 mg/kg/d systemic HPE injections; high-dose treatment (HT), 40 mg/kg/d systemic HPE injections). Surviving skin flap areas were measured 7 days after surgery and tissue samples were stained with hematoxylin and eosin; vascular endothelial growth factor expression was determined immunohistochemically. To evaluate the antioxidant and antiapoptotic effects of HPE, malondialdehyde, glutathione peroxidase, and caspase-3 levels were examined. Results: Seven days after surgery, HPE-treated animals had significantly reduced necrotic areas, rats receiving the highest HPE dose demonstrated the greatest flap survival. In the HPE groups, the histopathological scores were lower than for the control group. Immunohistochemistry showed markedly more numerous vascular endothelial growth factor-positive cells in the HT group than in the C group. Malondialdehyde levels were significantly lower and glutathione peroxidase levels were higher in the HT group than in the C group. HPE treatment significantly inhibited apoptosis by lowering caspase-3 activity. Conclusions: HPE treatment yielded positive effects on flap survival, due to its antioxidant and antiapoptotic properties. These results suggest a new therapeutic approach for enhancing flap viability and accelerating wound repair.  相似文献   
90.
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