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71.

Objectives

The relationships between filtered QRS duration and ventricular dyssynchrony were studied.

Methods

We measured filtered QRS duration on signal-averaged electrocardiography and analyzed tissue Doppler imaging in chronic heart failure patients with ejection fraction less than 50%.

Results

In 64 patients, interventricular and intraventricular dyssynchronies were observed in 25 and 38 patients, respectively. All patients with interventricular dyssynchrony were associated with intraventricular dyssynchrony. Filtered QRS showed 0.82 and 0.78 of the area under the curve (AUC) in the receiver operating characteristic curve (ROC) for the detection of interventricular and intraventricular dyssynchrony, respectively, with 89.7% and 96.2% specificity and 52.0% and 52.6% sensitivity, with cutoff values of 174 and 153 milliseconds. Specificity and sensitivity as well as AUC were lower in the ROC of QRS duration than filtered QRS duration.

Conclusion

Filtered QRS duration provided more reliable information to estimate ventricular dyssynchrony in patients with reduced ventricular ejection fraction than QRS duration did.  相似文献   
72.
To examine whether donor-derived cells could exist in nonhematopoietic tissues of recipients after allogeneic hematopoietic stem-cell transplantation, we examined the patterns of the short tandem repeat (STR) of DNA extracted from fingernail clippings of recipients so that the contamination of blood cells was excluded. All 21 patients reached donor-derived hematopoiesis after transplantation and 20 of them were in remission of the primary diseases at the time of sampling. Compared with the STRs of donor cells, among 9 of 21 patients, DNA extracted from fingernail samples showed coexistence of the donor pattern of the STRs, sharing from 8.9% to 72.9% of total STR areas. Time from transplantation to sampling was from 305 to 2399 days among positive cases. These results demonstrate for the first time the existence of stable contribution of donor cells in fingernails among recipients of allogeneic hematopoietic stem cells.  相似文献   
73.
The aim of this study was to evaluate the role of positron emission tomography (PET) with 18F-fluoro-2-deoxy-D-glucose (18F-FDG) in the restaging of hepatocellular carcinoma (HCC) treated with radiofrequency ablation (RFA). This study was performed on 33 lesions in 24 patients with HCC. 18F-FDG PET and computed tomography (CT) studies were performed in all patients before treatment. PET acquisition was started 50-60 min after injection of 18F-FDG (5-6 MBq/kg). Semi-quantitative analysis using Standardized Uptake Value (SUV) was measured for the evaluation of tumour 18F-FDG uptake. All patients underwent RFA treatment and were followed up at least 2 years with 18F-FDG PET, CT and clinical evaluation in the interval of every 3 months in the first year and every 6 months in the second year. 18F-FDG PET detected recurrence earlier than CT between 4-6 months in 2 patients and between 7-9 months in 6 patients whereas CT was positive in 4 patients. Overall detection rate of recurrence with 18F-FDG PET was 92% which was higher than that of CT (75%). Statistically significant difference in the SUV was observed between well and moderately differentiated HCC (p=0.033) and also between well and poorly differentiated HCC (p=0.037). The size of tumours showed a significant correlation with the time of recurrence (p<0.00033, r=0.8601, n=12). The results of this study indicate that 18F-FDG PET could detect recurrence earlier in patients with HCC treated with RFA, as compared with CT and could diagnose extrahepatic lesions. SUV showed a significant correlation with time of recurrence after RFA. 18F-FDG PET may be a dominant imaging modality as a follow-up procedure of HCC after RFA, in terms of early detection of recurrence.  相似文献   
74.
A 42-year-old man suffering from massive aortic valve regurgitation with mild stenosis because of a bicuspid valve underwent surgery in May 2007. The surgical procedure was performed through a right anterolateral thoracotomy using the peripheral cannulation method. Cardiac arrest was achieved by direct aortic cross-clamping and selective cardioplegia delivery. The aortic valve was replaced with a bioprosthesis. The operation and aortic cross-clamping periods were 265 and 117 min, respectively. The patient's recovery was uneventful, and he was discharged from hospital 8 days after surgery.  相似文献   
75.
Seawater sample from the coral reefs of the Kerama Islands of Okinawa were assessed for the presence of carotenoid-producing bacteria. Results of 16S rDNA analysis of the bacteria obtained from the isolated bacteria showed unique patterns that were different from those of the bacteria obtained from the ordinary marine area. Phylogenetic analysis revealed a slight correlation with the statistical analysis of the PDA chart patterns. The results suggest that useful materials for human health such as carotenoids can be extracted from many carotenoid-producing bacteria such as those found the coral reefs the Kerama Islands.  相似文献   
76.
Four new cardenolide monoglycosides, cardenolides N-1 (1), N-2 (2), N-3 (3), and N-4 (4), were isolated from Nerium oleander, together with two known cardenolides, 5 and 12, and seven cardenolide monoglycosides, 6-11 and 13. The structures of compounds 1-4 were established on the basis of their spectroscopic data. The in vitro anti-inflammatory activity of compounds 1-13 was examined on the basis of inhibitory activity against the induction of the intercellular adhesion molecule-1 (ICAM-1). Compounds 1, 5, 6, and 11-13 were active at an IC50 value of less than 1 microM. The cytotoxicity of compounds 1-13 was evaluated against three human cell lines, normal human fibroblast cells (WI-38), malignant tumor cells induced from WI-38 (VA-13), and human liver tumor cells (HepG2). Compounds 1, 4, 6, and 11-13 were active toward V-13 cells, and compounds 1, 11, and 12 were active toward HepG2 cells at IC50 values of less than 1 microM. Compounds 4, 5, 10, and 12 showed selective cell growth inhibitory activity toward V-13 tumor cells compared with that of parental normal WI-38 cells. The MDR-reversal activity of compounds 1-13 was evaluated on the basis of the amount of calcein accumulated in MDR human ovarian cancer 2780AD cells in the presence of each compound. Compounds 4, 9, and 10 showed significant effects on calcein accumulation, compound 4 showing stronger activity than that of verapamil.  相似文献   
77.
78.
RATIONALE AND OBJECTIVES: Our goals were to apply perfusion CT technique to breast tumor and to evaluate the correlation between arterial perfusion value and other tumor characteristics. MATERIALS AND METHODS: Thirty-one female patients with primary breast tumors were included in this study. A single-slice dynamic CT was performed after an intravenous bolus injection of contrast material (40 ml; 370 mg I/ml) at 8 ml/sec. The parameters were calculated on a pixel-by-pixel basis by using maximum slope method, and quantitative maps of arterial perfusion were created. Statistical correlation between tumor size, patient age, and perfusion were assessed. Differences in perfusion between scirrhous and nonscirrhous carcinoma were also assessed. RESULTS: Perfusion CT images were successfully created for 24 patients (mean age, 55.9 years old; range, 36-85 years). In five patients, dynamic CT was not performed due to lack of visualization of the breast tumor on unenhanced CT. In two patients, reliable perfusion CT image could not be created because of motion artifact. The mean perfusion for 24 tumors was 33.1 +/- 16.9 ml/min/100 ml (mean +/- SD; range, 14-78), and the tumor perfusion did not correlate with patient's age or tumor size (21.0 +/- 10.2 mm; range, 10-45 mm). The mean perfusion of nonscirrhous carcinoma (45.8 ml/min/100 ml; n = 11) was higher than that of scirrhous carcinoma (22.7 ml/min/100 ml; n = 11; P < .001). CONCLUSION: Determination of the perfusion of breast carcinoma is feasible by dynamic CT and can be performed during a routine CT study without much supplementary burden on the patient. There are differences in blood flow between scirrhous and nonscirrhous breast carcinoma, and further research is needed to determine the impact of this finding.  相似文献   
79.
Tsushima F  Yao S  Shin T  Flies A  Flies S  Xu H  Tamada K  Pardoll DM  Chen L 《Blood》2007,110(1):180-185
Although self-reactive T-cell precursors can be eliminated upon recognition of self-antigen presented in the thymus, this central tolerance process is often incomplete, and additional mechanisms are required to prevent autoimmunity. Recent studies indicates that the interaction between B7-H1 and its receptor PD-1 on activated T cells plays an important role in the inhibition of T-cell responses in peripheral organs. Here, we show that, before their exit to the periphery, T cells in lymphoid organs rapidly up-regulate PD-1 upon tolerogen recognition. Ablation of the B7-H1 and PD-1 interaction when T cells are still in lymphoid organs prevents anergy. Furthermore, blockade of B7-H1 and PD-1 interaction could render anergic T cells responsive to antigen. Our results thus reveal previously unappreciated roles of B7-H1 and PD-1 interaction in the control of initiation and reversion of T-cell anergy.  相似文献   
80.

Objective

L-3-[18F]-fluoro-α-methyl tyrosine (18F-FAMT) is an amino acid tracer for positron emission tomography/computed tomography (PET/CT) which specifically transported into cancer cells by L-type amino acid transporter 1 (LAT1). LAT1 overexpression in tumors is significantly correlated with cell proliferation and angiogenesis. 18F-FAMT PET/CT, fluorine-18-fluorodeoxyglucose (18F-FDG) PET/CT and magnetic resonance imaging (MRI) were compared for their diagnostic performance in the detection of bone marrow invasion in patients with oral squamous cell carcinoma (OSCC).

Methods

Twenty-seven patients with OSCC on the upper or lower alveolar ridge underwent staging by MRI, 18F-FDG PET/CT and 18F-FAMT PET/CT studies before surgery. Post-surgical pathologic examination was used as the standard to determine the final diagnoses. The possibility of bone marrow invasion on MRI, 18F-FDG PET/CT and 18F-FAMT PET/CT were usually graded retrospectively into five-point score. Sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were calculated according to the obtained scores.

Results

As the sensitivity of 18F-FDG PET/CT was highest (100 %) among that of MRI (95 %) and 18F-FAMT PET/CT (90 %), the specificity of 18F-FAMT PET/CT was highest (85.7 %) among that of MRI (57 %) and 18F-FDG PET/CT (14.3 %). The size of pathological tumor was accorded with that detected by 18F-FAMT PET/CT and was smaller than that detected by 18F-FDG PET/CT (P < 0.01). Significant difference was not found between 18F-FAMT PET tumor volume and pathological tumor volume.

Conclusions

18F-FAMT PET/CT was useful and more specific than MRI or 18F-FDG PET/CT in the detection of bone marrow invasion of OSCC and may contribute to minimize the extent of resection in oral surgery patient.  相似文献   
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