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71.

Background

To evaluate the haemodynamic changes induced by flow diversion treatment in cerebral aneurysms, resulting in thrombosis or persisting aneurysm patency over time.

Method

Eight patients with aneurysms at the para-ophthalmic segment of the internal carotid artery were treated by flow diversion only. The clinical follow-up ranged between 6?days and 12?months. Computational fluid dynamics (CFD) analysis of pre- and post-treatment conditions was performed in all cases. True geometric models of the flow diverter were created and placed over the neck of the aneurysms by using a virtual stent-deployment technique, and the device was simulated as a true physical barrier. Pre- and post-treatment haemodynamics were compared, including mean and maximal velocities, wall-shear stress (WSS) and intra-aneurysmal flow patterns. The CFD study results were then correlated to angiographic follow-up studies.

Results

Mean intra-aneurysmal flow velocities and WSS were significantly reduced in all aneurysms. Changes in flow patterns were recorded in only one case. Seven of eight aneurysms showed complete occlusion during the follow-up. One aneurysm remaining patent after 1?year showed no change in flow patterns. One aneurysm rupturing 5?days after treatment showed also no change in flow pattern, and no change in the maximal inflow velocity.

Conclusions

Relative flow velocity and WSS reduction in and of itself may result in aneurysm thrombosis in the majority of cases. Flow reductions under aneurysm–specific thresholds may, however, be the reason why some aneurysms remain completely or partially patent after flow diversion.  相似文献   
72.
The objective was to evaluate the effects of a stress management cognitive behavioural therapy followed during pregnancy on subsequent childhood on hair cortisol at birth and on neurodevelopment and Hair Cortisol Concentrations (HCC) at 6 months of age. The study sample included 48 pregnant women, divided into two groups: 24 women in the Therapy Group (TG) and 24 women who received standard pregnancy care (control group (CG); CG). To test the therapy efficacy, an evaluation of the HCC and psychological stress, psychopathological symptomatology and resilience was conducted before and after the treatment. The level of cortisol in their hair was obtained during pregnancy and that of their babies at birth. Six months after birth, a cortisol sample was taken from the hair and the babies' neurodevelopment was evaluated based on a Bayley-III test. The TG presented reductions in psychological stress and psychopathological symptomatology after treatment. On the other hand, the CG increased their cortisol concentrations between the pre and post intervention, remaining stable in the TG. Moreover, results showed that TG babies had lower cortisol concentrations at birth and obtained significantly higher cognitive and motor development scores at 6 months. These findings support that providing psychological care to pregnant women may not only have a benefit on these women's mental state, but may also benefit the neurodevelopment of their offspring.  相似文献   
73.
In the field of legal medicine the correct determination of the time of death is of great importance because an error in calculating the post-mortem interval (PMI) could be crucial in a criminal investigation. The quantification of hypoxanthine (Hx) concentration in the vitreous humor (VH) as a means to estimate PMI is useful when dealing with a recent time interval of death and has several advantages over other biological matrices. However, due to its viscous nature, VH has to be liquefied prior to its analysis, and the different procedures to liquefy it may cause alterations in Hx concentration, and hence in estimation of PMI. The aim of this study was to determine differences in Hx concentration after applying several pre-analytical treatments to different aliquots of the same VH sample. Enzymatic digestion, sonication, centrifugation and heat were the liquefying methods applied to reduce the viscosity of 105 VH samples. Analysis was performed using solid phase extraction and liquid chromatography in tandem with mass spectrometry. Statistically significant differences in the measured Hx concentrations were found between enzymatic digestion and the other three methods analyzed (sonication, centrifugation, and heat). Additionally, high data dispersion was found under heat treatment but was not observed for centrifugation or sonication, where similar and more moderate results were found. We conclude that high variations in Hx determination are observed when enzymatic digestion or heat treatment is used and we therefore recommend sonication or centrifugation to quantify Hx concentration in the VH.  相似文献   
74.
BACKGROUND: This study evaluated the prevalence of the atherogenic metabolic triad and the hypothesis that waist circumference and fasting triglyceride concentrations could be used as screening tools for identification of the atherogenic metabolic triad in a population of heart transplant men. It also evaluated the relationship between the atherogenic metabolic triad and coronary artery disease (CAD). METHODS: In the study group of 83 consecutive male heart transplant patients having their routine annual coronarography, 23 patients (28%) were characterized by the atherogenic metabolic triad defined by the presence of elevated fasting insulin and apolipoprotein B concentrations and by small low-density lipoprotein (LDL) particles. RESULTS: Seventy-seven per cent of patients with waist circumference values >/= 90 cm and with elevated triglyceride levels (>/=2.0 mmol/liter) were characterized by this atherogenic metabolic triad. Patients with the atherogenic metabolic triad were at markedly increased risk of CAD (odds ratio of 25.3, 95% CI: 1.11-577.3, p < 0.04) compared to heart transplant patients without the atherogenic metabolic triad. CONCLUSIONS: About 30% of heart transplant patients showed the features of the atherogenic metabolic triad. Measurement and interpretation of waist circumference and fasting triglycerides could be used among heart transplant patients to early identify men characterized by the presence of elevated fasting insulin and apolipoprotein B concentrations and small LDL particles. The presence of the atherogenic metabolic triad identified patients at high risk of CAD even in the heart transplant population.  相似文献   
75.
De novo donor‐specific antibodies (dDSA) relevance in simultaneous pancreas–kidney (SPK) transplantation has been scarcely investigated. We analyzed dDSA relationship with grafts outcomes in a long‐term follow‐up SPK‐transplanted cohort. In 150 patients that received SPK transplant between 2000 and 2013, post‐transplant anti‐human leukocyte antigen (HLA) antibodies were screened and identified using Luminex‐based assays in sera collected at 3, 6, and 12 months, then yearly. dDSA were detected in 22 (14.7%) patients at a median 3.1 years after transplant. Pretransplant anti‐HLA sensitization (OR = 4.64), full HLA‐DR mismatch (OR = 4.38), and previous acute cellular rejection (OR = 9.45) were significant risk factors for dDSA. dDSA were significantly associated with kidney (in association with acute rejection) and pancreas graft failure. In dDSA+ patients, those with at least one graft failure presented more frequently dDSA against class II or I + II (P = 0.011) and locusDQ (P = 0.043) and had a higher median dDSA number (P = 0.014) and strength (P = 0.030). Median time between dDSA emergence and pancreas and kidney graft failure was 5 and 12 months, respectively. Emergence of dDSA increased the risk of grafts failure in SPK‐transplanted patients. Full HLA‐DR mismatch was associated with dDSA emergence. dDSA characteristics might help identify patients at a higher risk of graft failure.  相似文献   
76.
The treatment of gastric cancer requires a multidisciplinary approach in which surgery plays the main role. The diffusion of minimally invasive surgery for gastric cancer treatment is limited by the complexity of performing an extended lymphadenectomy. This surgical step can be facilitated through the use of a robot-assisted system. To date, there are few published articles discussing a full robotic approach that precisely show the different surgical steps. The aim of this study is to describe our experience, surgical techniques and the short-term results of a consecutive series of full robotic gastrectomies using the Da Vinci Surgical System. From November 2011 to January 2015, 17 patients with gastric cancer underwent curative resection by robotic approach for locally advanced tumors. In summary, there were 15 total gastrectomies with a Roux-en-Y esophagojejunostomy, one total gastrectomy with transverse colectomy and one sub-total gastrectomy. Resection margins were negative in all cases. Conversions occurred in two patients. Robot-assisted gastrectomy with extended lymphadenectomy is a safe technique and successfully allows an adequate lymph node harvest and optimal R0-resection rates with low postoperative morbidity. The learning curve appears to be shorter than in laparoscopic surgery. Further follow-up and randomized clinical trials are required to confirm the role of a robotic approach in gastric cancer surgery.  相似文献   
77.
C1q nephropathy (C1qN) is a rare idiopathic glomerulopathy typically seen in adolescents and young adults. All kidney biopsies done from 2002 to 2007 were analyzed (264). Thirteen cases of C1qN from 212 (6.6%) native biopsies and one case out of 52 (1.9%) transplant biopsies were reviewed regarding demographic features, clinical presentation, histopathology, treatment, and outcome. Age varied from 1 to 18 years; half were boys. Ten children (71.4%) presented with nephrotic syndrome (NS). The most common histopathology found was diffuse mesangial proliferative glomerulonephritis (DMP) by light microscopy (LM), with diffuse granular staining for C1q predominantly in the mesangium. Children with either NS or persistent gross hematuria received prednisone and angiotensin-converting enzyme inhibitors (ACEi) (11). Median follow-up was 36 months. Steroid response was complete in 6 patients (54.5%). Those with steroid resistance (5) or steroid dependence (2) received further immunosuppression with mycophenolate mofetil (MMF) or tacrolimus (Tac). Three children achieved complete remission and four partial remission. Frequent relapses were seen in 4/14 patients. Renal survival was 100%. Our report reveals a high incidence of C1qN in pediatric patients, with variable clinical presentation. Despite a high incidence of steroid resistance among those with NS, an excellent response was observed with the addition of further immunosuppression.  相似文献   
78.

Purpose

The purpose of this study was to analyse the outcome and its influencing factors in patients whose therapy was converted from calcineurin inhibitors (CNI) to sirolimus (SRL) due to chronic allograft nephropathy (CAN).

Materials and methods

Therapies of 78 patients (44 men) with CAN from three European transplant centres were converted from CNI therapy to SRL and followed 24 months. Slopes for creatinine clearance before and after conversion were calculated. Influencing factors were analysed by a multivariance analysis.

Results

The slope of the creatinine clearance improved significantly (?0.90 vs. ?0.34 ml min?1 month?1; p?<?0.01). In patients whose therapy was converted from cyclosporine A (CyA) to SRL, the slope improved significantly, whereas conversion from Tacrolimus (Tac) to SRL did not affect the slope. The benefit was more pronounced in (1) patients with low or moderate baseline creatinine clearance, (2) patients receiving SRL after conversion without additional mycophenolate mofetil and (3) patients with low or moderate proteinuria.

Conclusion

Conversion from CyA to SRL but not from Tac to CRL is associated with a reduced loss of renal allograft function in patients with CAN.  相似文献   
79.

Introduction

Patients with a diagnosis of breast ductal carcinoma in situ (DCIS) have a low risk of developing axillary metastases. The use of sentinel node biopsy in this group of patients is controversial. The objective of this study is to determine if the sentinel node biopsy benefits a subgroup of patients with DCIS.

Patients and method

Between April 2002 and December 2007, patients with a diagnosis of DCIS and who underwent a sentinel node biopsy were included in the study. In our centre the sentinel node biopsy was performed in patients with DCIS who required a mastectomy, high grade and >2 cm DCIS and palpable DCIS.

Results

Forty-seven patients were included in the study. In all cases the sentinel node was identified. Twenty-five (53.1%) patients underwent a mastectomy due to extensive DCIS; 14 of these (56%) with immediate reconstruction with implants. Twenty-five (53.1%) patients had high grade DCIS. In 7 (14.8%) patients the tumour was palpable. Fourteen patients (29.7%) were upgraded to invasive breast cancer in the definitive histology. In 2 (4.2%) patients who underwent a mastectomy a positive sentinel node was found.

Conclusions

Performing sentinel node biopsy in this group of DCIS patients has lead us to identify 4% of patients with positive sentinel nodes. Furthermore, 29.7% of the patients have avoided a second invasive diagnostic procedure for definitive histology. For these reasons we consider it appropiate to perform sentinel node biopsy in this subgroup of patients with DCIS of the breast.  相似文献   
80.

Objective

One of the most interesting clinical applications of 18F-FDG PET imaging in neurodegenerative pathologies is that of establishing the prognosis of patients with mild cognitive impairment (MCI), some of whom have a high risk of progressing to Alzheimer’s disease (AD). One method of analyzing these images is to perform statistical parametric mapping (SPM) analysis. Spatial normalization is a critical step in such an analysis. The purpose of this study was to assess the effect of using different methods of spatial normalization on the results of SPM analysis of 18F-FDG PET images by comparing patients with MCI and controls.

Methods

We evaluated the results of three spatial normalization methods in an SPM analysis by comparing patients diagnosed with MCI with a group of control subjects. We tested three methods of spatial normalization: MRI-DARTEL and MRI-SPM8, which combine structural and functional images, and FDG-SPM8, which is based on the functional images only.

Results

The results obtained with the three methods were consistent in terms of the main pattern of functional alterations detected; namely, a bilateral reduction in glucose metabolism in the frontal and parietal cortices in the patient group. However, MRI-SPM8 also revealed differences in the left temporal cortex, and MRI-DARTEL revealed further differences in the left temporal cortex, precuneus, and left posterior cingulate.

Conclusions

The results obtained with MRI-DARTEL were the most consistent with the pattern of changes in AD. When we compared our observations with those of previous reports, MRI-SPM8 and FDG-SPM8 seemed to show an incomplete pattern. Our results suggest that basing the spatial normalization method on functional images only can considerably impair the results of SPM analysis of 18F-FDG PET studies.  相似文献   
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