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51.
After kidney transplantation, C4d is an incomplete marker of acute antibody‐mediated rejection (AMR) and C1q‐binding donor‐specific antibodies (DSA) have been associated with allograft survival. However, the impact on allograft survival of C1q+ DSA after clinical AMR has not been studied yet. We analysed retrospectively in clinical AMR C4d staining and C1q‐binding impact on allograft survival. We compared clinical, histological and serological features of C4d− and C4d+ AMR, C1q+ and C1q− DSA AMR and analysed C4d and C1q‐binding impact on allograft survival. Among 500 for‐cause kidney allograft biopsies, 48 fulfilled AMR criteria. C4d+ AMR [= 18 (37.5%)] have significantly higher number class I DSA (P = 0.02), higher microvascular score (P = 0.02) and more transplant glomerulopathy (P = 0.04). C1q+ AMR [N = 20 (44%)] presented with significantly more class I and class II DSA (P = 0.005 and 0.04) and C4d+ staining (P = 0.01). Graft losses were significantly higher in the C4d+ group (P = 0.04) but similar in C1q groups. C4d+ but not C1q+ binding was an independent risk factor for graft loss [HR = 2.65; (1.11–6.34); P = 0.028]. In our cohort of clinical AMR, C4d+ staining but not C1q+ binding is an independent risk factor for graft loss. Allograft loss and patient survival were similar in C1q+ and C1q− AMR.  相似文献   
52.
In 2002, the United Network for Organ Sharing proposed increasing the pool of donor kidneys to include Expanded Criteria Donor (ECD). Outside the USA, the ECD definition remains the one used without questioning whether such a graft allocation criterion is valid worldwide. We performed a meta‐analysis to quantify the differences between ECD and Standard Criteria Donor (SCD) transplants. We paid particular attention to select studies in which the methodology was appropriate and we took into consideration the geographical area. Thirty‐two publications were included. Only five studies, all from the USA, reported confounder‐adjusted hazard ratios comparing the survival outcomes between ECD and SCD kidney transplant recipients. These five studies confirmed that ECD recipients seemed to have poorer prognosis. From 29 studies reporting appropriate survival curves, we estimated the 5‐year pooled nonadjusted survivals for ECD and SCD recipients. The relative differences between the two groups were lower in Europe than in North America, particularly for death‐censored graft failure. It is of primary importance to propose appropriate studies for external validation of the ECD criteria in non‐US kidney transplant recipients.  相似文献   
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Background

Morbidity after gastrectomy remains high. The potentially modifiable risk factors have not been well described. This study considers a series of potentially modifiable patient-specific and perioperative characteristics that could be considered to reduce morbidity and mortality after gastrectomy.

Methods

This retrospective cohort study includes adults in the ACS NSQIP PUF dataset who underwent gastrectomy between 2011 and 2013. Sequential multivariable models were used to estimate effects of clinical covariates on study outcomes including morbidity, mortality, readmission, and reoperation.

Results

Three thousand six hundred and seventy-eight patients underwent gastrectomy. A majority of patients had distal gastrectomy (N?=?2,799, 76.1 %) and had resection for malignancy (N?=?2,316, 63.0 %). Seven hundred and ninety-eight patients (21.7 %) experienced a major complication. Reoperation was required in 290 patients (7.9 %). Thirty-day mortality was 5.2 %. Age (OR?=?1.01, 95 % CI?=?1.01–1.02, p?=?0.001), preoperative malnutrition (OR?=?1.65, 95 % CI?=?1.35–2.02, p?<?0.001), total gastrectomy (OR?=?1.63, 95 % CI?=?1.31–2.03, p?<?0.001), benign indication for resection (OR?=?1.60, 95 % CI?=?1.29–1.97, p?<?0.001), blood transfusion (OR?=?2.57, 95 % CI?=?2.10–3.13, p?<?0.001), and intraoperative placement of a feeding tubes (OR?=?1.28, 95 % CI?=?1.00–1.62, p?=?0.047) were independently associated with increased risk of morbidity. Association between tobacco use and morbidity was statistically marginal (OR?=?1.23, 95 % CI?=?0.99–1.53, p?=?0.064). All-cause postoperative morbidity had significant associations with reoperation, readmission, and mortality (all p?<?0.001).

Conclusions

Mitigation of perioperative risk factors including smoking and malnutrition as well as identified operative considerations may improve outcomes after gastrectomy. Postoperative morbidity has the strongest association with other measures of poor outcome: reoperation, readmission, and mortality.
  相似文献   
54.
Advancements in burn care therapy have extended survival of seriously burned patients, exposing burn patients to increased risk of infectious complications, notably fungal infections. We performed a 12-year review of autopsied patients with severe burns for the presence of fungal infection at the US Army Institute of Surgical Research Burn Center between February 1991 and November 2003. The primary goal was to identify the relationship between fungal element noted in autopsy and mortality, and to determine contributing factors that increase a patient's susceptibility to fungal infection. A total of 228 deaths (6.1%) resulted from the 3751 admissions of which 97 underwent autopsy. Fungal elements were identified on histopathology in 44% (43 of 97) of autopsied patients with an attributable mortality of 33% (14 of 43). Aspergillus and Candida were the most frequently recovered fungi, but Aspergillus was recovered in 13 of the 14 cases with fungus identified as an attributable cause of death. The most common sites of infections with attributable mortality were wounds (86%) and the pulmonary system (14%). Total body surface area (TBSA) burn and length of stay (survival after burn) were identified as contributing factors for the incidence of fungal element in autopsy on ROC curve analysis. More severely injured patients with greater %TBSA burn injury and full-thickness burns require a longer recovery period resulting in a longer hospital stay. The propensity for fungal infection increases the longer the wound is present. Therefore, the development of products to close the wound more rapidly, improvement in topical antifungal therapy with mold activity for treating wounds, and implementation of appropriate systemic antifungal therapy may improve outcome for severely injured burn victims susceptible to fungal infections.  相似文献   
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56.

Background

The right ventricular ejection fraction (RVEF) is a surrogate marker of right ventricular function in pulmonary hypertension (PH), but its measurement is complicated and time consuming. The tricuspid annular plane systolic excursion (TAPSE) measures only the longitudinal component of RV contraction while the right ventricular fractional area change (RVFAC) takes into account both the longitudinal and the transversal components. The aim of our study was to evaluate the relationship between RVEF, RVFAC, and TAPSE according to hemodynamic severity in two groups of patients with PH: pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH).

Methods and Results

Fifty-four patients with PAH (n?=?15) and CTEPH (n?=?39) underwent right heart catheterization and cardiac magnetic resonance (CMR). The ventricular volumes and areas, TAPSE, and eccentricity index were measured. The RVFAC was more strongly correlated with the RVEF (r?=?0.81, p?<?0.0001) than the TAPSE (r?=?0.63, p?<?0.0001). RVEF?<?35% was better predicted by the RVFAC than the TAPSE (TAPSE: AUC?=?0.77 and RVFAC: AUC?=?0.91; p?=?0.042). In the group with the worse hemodynamic status, the RVFAC correlated much better with the RVEF than the TAPSE. There were no significant differences in the CMR data analyzed between the groups of PAH and CETPH patients.

Conclusions

The RVFAC is a good index to estimate RVEF in PH patients; even better than the TAPSE in patients with more severe hemodynamic profile, possibly for including the transversal component of right ventricular function in its measurement. Furthermore, RVFAC performance was similar in the two PH groups (PAH and CTEPH).
  相似文献   
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