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61.
Helicobacter pylori eradication induces platelet recovery in a subgroup of patients with chronic immune thrombocytopenia (cITP), but the mechanisms involved are still not understood. We aimed to evaluate the effect of H. pylori eradication on platelet response and to identify the associated serum cytokine profile in 95 patients with cITP. Serum cytokine concentrations were determined by enzyme‐linked immunosorbent assay prior to and 6 months after H. pylori eradication. Remission of cITP was observed in 17 (28·8%) of 59 patients in whom the bacterium was eradicated. Six months after treatment, a significant reduction in the concentrations of T‐helper (Th) 1 and Th17 cells and an increase in T regulatory (Treg) and Th2‐cell commitment cytokines were observed in patients who recovered, but not in those whose platelet count did not recover. Patients who had a platelet response to eradication of the bacteria had higher pre‐treatment serum levels of γ‐interferon (IFNG, IFN‐γ), transforming growth factor‐β (TGFB1, TGF‐β) and interleukin 17 (IL17A, IL‐17) than patients who did not respond, but only higher pre‐treatment TGFB1 levels was independently associated with platelet response. In conclusion, amelioration of cITP after eradication of H. pylori was linked to a more efficient suppression of Th1 and Th17 response and a more pronounced Treg cell response.  相似文献   
62.

Background

The electrocardiogram (ECG) is one of the most non-invasive techniques to give support to the atrial fibrillation (AF) diagnosis. Several authors use the temporal difference between two consecutive R waves, a method known as RR interval, to perform the AF diagnosis. However, RR interval-based analysis does not detect distortions on the other ECG waves.

Purpose

Thus, the present work proposes a diagnostic decision support systems for AF based on higher order spectrum analysis of the voltage variation on the ECG..

Methods

The proposed method was used aiming AF classifying. The classifier is composed by two screening stages: one based on the average and another on the average deviation of kurtosis of the ECG signals. Heartbeat obtained from the MIT-BIH atrial fibrillation and MIT-BIH normal were used.

Results

ECG signal featured by kurtosis outperforms second order statistics based metrics in up to 476 times, and up to 110 times above the RR interval. The screening methods obtained sensitivity equal to 100% and specificity is up to 84.04%. The two screening methods combined provided an AF classifier with an accuracy rate at diagnosis of 100%. The results presented take into account windows of up to five heartbeats and a 99.73% confidence interval.

Conclusion

The results obtained by the proposed method can be used to support decision-making in clinical practices with a diagnostic accuracy rate of 90.04% to 100%.  相似文献   
63.
64.
Twenty‐seven patients with resistant hypertension and chronic kidney disease were treated by renal sympathetic denervation (RSD) and followed for 12 months. Patients were retrospectively divided into controlled and uncontrolled blood pressure (BP) groups. Increases in mean estimated glomerular filtration rate (eGFR) were found at months 1, 3, 6, and 12 in the controlled group (P<.0001, for every time point). The mean change in eGFR after 12 months was 18.54±8.15 mL/min/1.73m2 higher in the controlled group (P=.0318). In patients in the controlled group with baseline eGFR <45 mL/min/1.73 m2, responders (with an increase in eGFR >6.2%) corresponded to 50% at 6 months and 83% at 12 months. In the patients with baseline eGFR ≥45 mL/min/1.73 m2, all patients were labeled as responders at months 6 and 12. Median albumin:creatinine ratio after 12 months was lower than baseline only in the controlled group (P=.0003). Our results suggest that patients with this profile who reached BP control by RSD also experienced a significant improvement in renal function.  相似文献   
65.
66.

OBJECTIVE:

To describe lung function findings in overweight children and adolescents without respiratory disease.

METHODS:

This was a cross-sectional study involving male and female overweight children and adolescents in the 8-18 year age bracket, without respiratory disease. All of the participants underwent anthropometric assessment, chest X-ray, pulse oximetry, spirometry, and lung volume measurements. Individuals with respiratory disease were excluded, as were those who were smokers, those with abnormal chest X-rays, and those with an SpO2 = 92%. Waist circumference was measured in centimeters. The body mass index-for-age Z score for boys and girls was used in order to classify the individuals as overweight, obese, or severely obese. Lung function variables were expressed in percentage of the predicted value and were correlated with the anthropometric indices.

RESULTS:

We included 59 individuals (30 males and 29 females). The mean age was 11.7 ± 2.7 years. Lung function was normal in 21 individuals (35.6%). Of the 38 remaining individuals, 19 (32.2%), 15 (25.4%), and 4 (6.7%) presented with obstructive, restrictive, and mixed ventilatory disorder, respectively. The bronchodilator response was positive in 15 individuals (25.4%), and TLC measurements revealed that all of the individuals with reduced VC had restrictive ventilatory disorder. There were significant negative correlations between the anthropometric indices and the Tiffeneau index in the individuals with mixed ventilatory disorder.

CONCLUSIONS:

Lung function was abnormal in approximately 65% of the individuals evaluated here, all of whom were overweight. Obstructive ventilatory disorder and positive bronchodilator response predominated.  相似文献   
67.
J Oral Pathol Med (2012) 41 : 630–636 Background: Several cell types are associated with the development of cystic and tumoral odontogenic lesions. Among inflammatory cells, mast cells can be associated with their pathogenesis. The aim of this study was to analyze mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors. Methods: Tissue sections were submitted to toluidine blue staining and immunohistochemistry with antibody anti‐tryptase (clone G3). Mast cells were quantitated using Image‐Pro Plus software to obtain the mean number of mast cells in three regions: epithelial, superficial portion of the fibrous wall and deep portion of the fibrous wall from 20 periapical cysts, 20 dentigerous cysts (six non‐inflamed and 14 inflamed) and 20 keratocystic odontogenic tumors (four non‐inflamed and 16 inflamed). Results: The mean number of mast cells detected per lesion by immunohistochemistry (4.1) was higher than by histochemistry (1.5) (P < 0.0001). Inflamed dentigerous cysts and keratocystic odontogenic tumors showed a higher mean number of mast cells than non‐inflamed lesions in all regions. The deep region from all cysts showed the highest mean number of degranulated mast cells, except for non‐inflamed keratocystic odontogenic tumors analyzed by immunohistochemistry. Conclusions: Immunohistochemical staining detected higher number of mast cells than histochemistry. The higher number of mast cells observed in inflamed lesions could indicate the participation of these cells in the inflammatory response in odontogenic lesions. The prevalence of degranulated mast cells in the deep region suggests intense activity of these cells, possibly related to growth of cystic lesions.  相似文献   
68.
The recognition of the student profile provides strategic information for planning educational policies in the university environment. The aims of this study were to identify natural segmentation of freshman undergraduate dental students based on demographic, socioeconomic and educational variables, and to subsequently investigate their impact on academic performance of Brazilian undergraduate students. Cluster analysis (two‐step algorithm) was used to segment students who entered dental school in the time period from 1999 to 2001 (n = 158) into groups based on responses to a questionnaire completed by students at the time of the admission examination. Clustering analysis revealed three natural groups. Age, the parents’ level of education, and performance on the first admission test were the most important variables for cluster segmentation. Cluster 1 (n = 42; 26.6%) was characterized by female students with higher socioeconomic status and better previous educational indicators. Cluster 2 (n = 62; 39.2%) represented disadvantaged socioeconomic profiles, with a predominance of females and older students. Cluster 3 (n = 54; 34.2%) showed similar socioeconomic characteristics to cluster 1, except for male prevalence, higher age, and experiencing difficulty in the admission test. Clusters’ academic performance was satisfactory in both overall course and course groups (grade point average of at least 7.0), with average ranging from 7.89 (SD = 0.44) to 8.13 (SD = 0.31) and 7.37 (SD = 0.75) to 8.31(SD = 0.26), respectively. Our findings provide encouraging evidence for the current context of equality of access to education and reveal the importance of financial support to maximize successful educational experiences of socioeconomically disadvantaged dental students.  相似文献   
69.

Background  

Glioblastoma remains one of the most devastating human malignancies, and despite therapeutic advances, there are no drugs that significantly improve the patient survival. Altered expression of the Aurora kinases was found in different malignancies, and their inhibition has been studied in cancer therapy. In this study, we analyzed the expression of Aurora A and Aurora B in glioblastoma samples and also analyzed whether the effects of Aurora kinase inhibition were associated with temozolomide or not on cell lines and primary cultures of glioblastoma.  相似文献   
70.
Despite the high incidence, the molecular events involved in intestinal-type gastric carcinogenesis remains unclear. We previously established an intestinal-type gastric carcinogenesis model in Cebus apella, a New World monkey. In the present study, we evaluated hTERT and TP53 mRNA expression, as well as their protein immunoreactivity, in normal mucosa, non-atrophic gastritis, atrophic gastritis, intestinal metaplasia, and intestinal-type gastric cancer samples of non-human primates treated with N-methyl-nitrosourea. In addition, we evaluated the number of TP53 copies in these samples. Although hTERT immunoreactivity was only detected in gastric cancer, a continuous increase of hTERT mRNA expression was observed from non-atrophic gastritis to gastric tumors. No sample presented p53 immunoreactivity. However, we also observed a continuous decrease of TP53 mRNA expression during the sequential steps of gastric carcinogenesis. Moreover, loss of TP53 copies was observed in intestinal metaplasia and gastric cancer samples. Our study highlights that hTERT and TP53 have a key role in intestinal-type gastric cancer initiation.  相似文献   
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