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Introduction

Pulmonary nocardiosis (PN) is a severe infection with a high morbidity and mortality that mainly affects immunocompromised patients. In recent years, an increase in PN cases has been detected among patients with chronic obstructive pulmonary disease (COPD). The factors that are associated with its presence and determine its prognosis remain unknown.

Methods

Retrospective study of COPD patients diagnosed with PN over the period from 1997-2009 at the Hospital de la Santa Creu i Sant Pau, in Barcelona (Spain). Demographic, clinical, microbiological and evolution data were evaluated in all cases

Results

Thirty patients were identified with PN and COPD. Mean age (standard deviation) was 76 (7) years and the mean FEV1 was 40 (14)%. Chronic respiratory failure was observed in 56,7% patients and 51,7% had received systemic corticosteroid therapy previous to the PN diagnosis. The most common symptoms were cough and dyspnea (90%). Alveolar infiltrates were observed in 60% of the cases. The most frequently isolated Nocardia species was N. cyriacigeorgica (68%). The one-month mortality rate was 17%, while the one-year mortality rate was 33%. The factors associated with mortality within the first year included previous systemic corticosteroid treatment, less than three months of specific antibiotic therapy and active associated neoplasm.

Conclusions

PN affects patients with moderate-severe COPD and has high short- and mid-term mortality rates. Previous corticosteroid treatment, specific antibiotic therapy for less than 3 months and active neoplasia were factors associated with mortality.  相似文献   
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Retrospective studies suggest that online hemodiafiltration (OL-HDF) may reduce the risk of mortality compared with standard hemodialysis in patients with ESRD. We conducted a multicenter, open-label, randomized controlled trial in which we assigned 906 chronic hemodialysis patients either to continue hemodialysis (n=450) or to switch to high-efficiency postdilution OL-HDF (n=456). The primary outcome was all-cause mortality, and secondary outcomes included cardiovascular mortality, all-cause hospitalization, treatment tolerability, and laboratory data. Compared with patients who continued on hemodialysis, those assigned to OL-HDF had a 30% lower risk of all-cause mortality (hazard ratio [HR], 0.70; 95% confidence interval [95% CI], 0.53–0.92; P=0.01), a 33% lower risk of cardiovascular mortality (HR, 0.67; 95% CI, 0.44–1.02; P=0.06), and a 55% lower risk of infection-related mortality (HR, 0.45; 95% CI, 0.21–0.96; P=0.03). The estimated number needed to treat suggested that switching eight patients from hemodialysis to OL-HDF may prevent one annual death. The incidence rates of dialysis sessions complicated by hypotension and of all-cause hospitalization were lower in patients assigned to OL-HDF. In conclusion, high-efficiency postdilution OL-HDF reduces all-cause mortality compared with conventional hemodialysis.In the last decades, renal replacement therapy with hemodialysis has become a standard of care for patients with ESRD. Despite continuous improvement, annual mortality among these patients ranges between 15% and 25%.1,2 Hemodialysis techniques are based on the ability of molecules to diffuse across a semipermeable membrane, which allows adequate clearance of low molecular weight particles. To increase the clearance of middle-to-large molecules, synthetic membranes with high water permeability (high-flux membranes) were introduced years ago. The anticipated benefit of high-flux over low-flux hemodialysis on patient survival was not confirmed in the Hemodialysis (HEMO) study.3 However, the Membrane Permeability Outcome (MPO) study,4 as well as a post hoc analysis in diabetic patients, showed that high-flux hemodialysis improved long-term survival in patients with hypoalbuminemia.Clearance of middle-to-large molecules can be increased by combining diffusive and convective transport through hemodiafiltration. The introduction of online hemodiafiltration (OL-HDF) using ultrapure dialysate as the source of the replacement fluid has allowed the convective volume to be increased and has reduced the cost of the procedure.5 Randomized studies with limited sample sizes and nonrandomized studies have shown that OL-HDF improves hemodynamic stability and response to erythropoietic-stimulating agents (ESAs) and reduces the incidence of hemodialysis-associated amyloidosis and chronic inflammation.611 The effect of OL-HDF on patient survival is derived from noncontrolled studies. The European Dialysis Outcomes and Practice Pattern Study was associated with a mortality risk reduction of 35% in patients treated with high-efficiency hemodiafiltration compared with those treated with conventional hemodialysis.12 These results were confirmed in other noncontrolled studies conducted in several European countries,1315 although two recent, randomized studies failed to show differences in patient survival16,17In 2007, the Catalonian Health Authorities approved a specific additional reimbursement for OL-HDF to dialysis care providers and the Catalonian Society of Nephrology promoted this randomized study (On-Line Hemodiafiltration Survival Study, or Estudio de Supervivencia de Hemodiafiltración On-Line [ESHOL]) to compare the effect of OL-HDF over hemodialysis on patient survival.18  相似文献   
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Purpose

The non-invasive expandable prosthesis for skeletally immature patients is used after limb salvage surgery following tumor resection. The aim of the study was to assess the effectiveness of this treatment.

Methods

Seven paediatric patients with femoral tumors had resection and limb salvage with an uncemented non-invasive growing prosthesis. Mean age at the time of surgery was 9.8 (range 8–12) years. There were six distal femur osteosarcomas and one proximal femur Ewing sarcoma. Six total knee prosthesis were implanted at the time of primary tumor resection and one bipolar hip prosthesis was a revision from a failed osteoarticular hip allograft. Functional outcomes and emotional acceptance were assessed using the MSTS score.

Results

The mean follow-up was 65.3 months (range 29–91) months. Two patients died of pulmonary metastasis and there was no local recurrence. The mean femoral resection was 18 cm (range 17–19) on the knee, and 24 cm on the hip. Mean total expansion was 36.4 mm (range 12.3–63.5). The mean MSTS score after rehabilitation was 26.3 (range 21–29). There was one lengthening device failure, one late infection and one patient who required iliofemoral bypass grafting surgery for a pelvic metastasis. No local recurrence occurred.

Conclusions

The non-invasive expandable prosthesis reduces the final limb-length discrepancy in growing patients with an acceptable function and appears to have an advantage as compared to invasive expandable prostheses which require multiple surgical procedures, but the complications rate is still high.
  相似文献   
28.

Purpose

In the diagnosis of head and neck melanoma, lymphatic drainage is complex and highly variable. As regional lymph node metastasis is one of the most important prognostic factors, lymphoscintigraphy can help map individual drainage patterns. The aim of this study was to compare the results of lymphoscintigraphy and sentinel lymph node (SLN) detection with theoretical anatomical patterns of lymphatic drainage based on the location of the primary tumour lesion in patients with head and neck melanoma. We also determined the percentage of discrepancies between our lymphoscintigraphy and the theoretical location of nodal drainage predicted by a large lymphoscintigraphic database, in order to explain recurrence and false-negative SLN biopsies.

Methods

In this retrospective study of 152 patients with head and neck melanoma, the locations of the SLNs on lymphoscintigraphy and detected intraoperatively were compared with the lymphatic drainage predicted by on-line software based on a large melanoma database.

Results

All patients showed lymphatic drainage and in all patients at least one SLN was identified by lymphoscintigraphy. Of the 152 patients, 4 had a primary lesion in areas that were not described in the Sydney Melanoma Unit database, so agreement could only be evaluated in 148 patients. Agreement between lymphoscintigraphic findings and the theoretical lymphatic drainage predicted by the software was completely concordant in 119 of the 148 patients (80.4 %, 95 % CI 73.3 – 86 %). However, this concordance was partial (some concordant nodes and others not) in 18 patients (12.2 %, 95 % CI 7.8 – 18.4 %). Discordance was complete in 11 patients (7.4 %, 95 % CI 4.2 – 12.8 %).

Conclusion

In melanoma of the head and neck there is a high correlation between lymphatic drainage found by lymphoscintigraphy and the predicted drainage pattern and basins provided by a large reference database. Due to unpredictable drainage, preoperative lymphoscintigraphy is essential to accurately detect the SLNs in head and neck melanoma.
  相似文献   
29.

Background

Adult spinal deformity (ASD) is a major public health problem. There are pros and cons of the available treatment alternatives (surgical or non-surgical) and it had been difficult to identify the best treatment modality.

Aim

To construct a statistical DA model to identify the optimum overall treatment in ASD.

Methods

From an international multicentre database of ASD patients (968 pts), 535 who had completed 1 year follow-up (371 non-surgical—NS, 164 surgical—S), constitute the population of this study. DA was structured in two main steps of: (1) baseline analysis (assessing the probabilities of outcomes, assessing the values of preference—utilities-, combining information on probability and utility and assigning the quality adjusted life expectancy (QALE) for each treatment) and (2) sensitivity analysis.

Results

Four hundred and thirty-two patients (309 NS, 123 S) had baseline and 1 year follow-up ODI measurements. Overall, 104 (24.1 %) were found to be improved (a decrease in ODI > 8 points), 225 (52.1 %) unchanged (?8 > ODI > 8) and 65 deteriorated. Surgery presented with a higher chance of improvement (54.2 %) versus NS (9.7 %). The overall QALE ranged from 56 to 69 (of 100 years) and demonstrated better final QALE in the NS group (60 vs. 65, P = 0.0038), this group having started with higher QALE as well (56 vs. 65 years, P < 0.0001). There were improvements in overall QALE in both groups but this was significant only in the surgical group (S from 56 to 60 years, P < 0.0001; NS from 65 to 65 years, P = 0.27). In addition, in the subgroup of patients with significant baseline disability (ODI > 25) surgery appeared to yield marginally better final QALE (58 vs. 56 years, P = 0.1) despite very a similar baseline (54 vs. 54 years, P = 0.93).

Discussion and conclusions

This study demonstrated that a single best treatment modality for ASD may not exist. Conservative treatment appears to yield higher (up to 6 %) QALE compared to surgery, most probably secondary to a higher baseline QALE. On the other hand, surgery provides a significantly higher increase in QALE. Especially in patients with significant disability at baseline, the final QALE tended higher in the S group (although not significant). Finally, chances of a relevant improvement at first year turned out to be significantly lower with NS treatment.
  相似文献   
30.
This study describes the development of the SAPS and investigates its reliability and validity within the context of the Health Behaviour in School-Aged Children Survey (HBSC) which gathered data on representative samples of school pupils aged 11, 13 and 15 in Scotland and England. In the development of SAPS, following a comprehensive review of the literature, two small-scale empirical studies were carried out (one qualitative and one quantitative). Regarding the validation process, the reliability and validity of the SAPS was assessed in a sub-sample (n?=?7159) of pupils who completed the HBSC survey and were identified as owning pets. Factor analysis resulted in a one-factor solution (explaining 67.78 % of the variance); Cronbach’s alpha for the scale was 0.894. The item-total correlation ranged from 0.368 to 0.784. A linear model showed that attachment to pets was associated with age (being 11 or 13 years old), being a girl, white ethnicity, and considering a pet as one’s own. SAPS scores were also positively associated with quality of life. The total variance in SAPS explained by these variables was 15.7 %. Effect sizes of associations were medium (age, considering a pet as one’s own) and small (ethnicity, age, gender, quality of life). The study concludes that SAPS is a coherent and psychometrically sound measure. It is associated with a range of demographic variables and quality of life, which confirms its utility as a new succinct measure of children’s and young people’s attachment to pets for use in health and social science research.  相似文献   
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