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Background

It is not known whether the neurotoxicity produced by anaesthetics administered to young animals can also occur in children. Exposure of infant macaques to ketamine impairs performance in selected domains of the Operant Test Battery (OTB), which can also be administered to children. This study determined whether a similar pattern of results on the OTB is found in children exposed to procedures requiring general anaesthesia before age 3 yr.

Methods

We analysed data from the Mayo Anesthesia Safety in Kids (MASK) study, in which unexposed, singly-exposed, and multiply-exposed children born in Olmsted County, MN, USA, from 1994 to 2007 were sampled using a propensity-guided approach and prospectively underwent OTB testing at ages 8–12 or 15–20 yr, using five tasks that generated 15 OTB test scores.

Results

In primary analysis, none of the OTB test scores depended upon anaesthesia exposure status when corrected for multiple comparisons. Cluster analysis identified four clusters of subjects, with cluster membership determined by relative performance on the OTB tasks. There was no evidence of association between exposure status and cluster membership. Exploratory factor analysis showed that the OTB scores loaded onto four factors. The score for one factor was significantly less in multiply-exposed children (mean standardised difference –0.28 [95% confidence interval, –0.55 to –0.01; P=0.04]), but significance did not survive a sensitivity analysis accounting for outlying values.

Conclusions

These findings provide little evidence to support the hypothesis that children exposed to procedures requiring anaesthesia show deficits on OTB tasks that are similar to those observed in non-human primates.  相似文献   
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A pilot oral health epidemiological survey using WHO assessment forms was conducted in Yugoslavia in the year 1986. The study population consisted of 2600 persons aged 6, 12, 15, 18, 35-44, and over 65 yr. The survey included 22 towns (11 developed and 11 underdeveloped) in the six Republics and two Provinces of Yugoslavia. The results showed the prevalence of dental caries in the Yugoslav population to be very high (98.7% in 12-yr-olds). The mean decayed, missing, and filled teeth (DMF) scores were as follows: 6.1 at age 12 yr, 9.6 at age 15, 10.9 at age 18, 18.0 at age 35-44, and 28.0 in persons aged over 65 yr. Assessment of the periodontal status showed calculus to be the predominant disorder in the age groups 18 and 35-44 yr, while loss of sextants prevailed in persons aged over 65 yr.  相似文献   
84.

Background

The etiological spectrum of pituitary stalk lesions (PSL) is wide and yet specific compared to the other diseases of the sellar and suprasellar region. Because of the pituitary stalk’s (PS) critical location and role, biopsies of these lesions are rarely performed, and their underlying pathology is often a conundrum for clinicians. A pituitary MRI in association with a clinical context can facilitate their diagnosis.

Aim

To present the various causes of PSL—their clinical, hormonal, histopathological, and MRI characteristics in order to gain better insight into this pathology.

Method

A retrospective observational study consisting of 53 consecutive patients with PSL of the mean age 32?±?4.2 years (range 6–67), conducted at the Department for Neuroendocrinology, Clinical Center of Serbia 2010–2018.

Results

Congenital malformations were the most common cause of PSL in 25 of 53 patients (47.1%), followed by inflammatory (9/53; 16.9%) and neoplastic lesions (9/53; 16.9%). The exact cause of PSL was established in 31 (58.4%) patients, of whom 23 were with congenital PS abnormalities and 8 with histopathology of PSL (7 neoplastic and 1 Langerhans Cell Hystiocytosis). A probable diagnosis of PSL was stated in 12 patients (22.6%): 6 with lymphocytic panhypophysitis, while Rathke cleft cyst, tuberculosis, dissemination of malignancy in PS were each diagnosed in 2 patients. In 10 patients (18.8%), the etiology of PSL remained unknown.

Conclusion

Due to the inability of establishing an exact diagnosis, the management and prognosis of PSL are difficult in many patients. By presenting a wide array of causes implicated in this condition, we believe that our study can aid clinicians in the challenging cases of this pathology.
  相似文献   
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OBJECTIVE: To address the role of serum gamma-glutamyl transferase (GGT) as a marker of metastases in patients with renal cell carcinoma. METHODS: Serum alkaline phosphatase and GGT were determined in 156 patients with localized renal cell carcinoma and 60 patients with metastases as proven by echosonography, computerized tomography and bone scan. The control group consisted of 50 healthy subjects matched for sex and age. Sensitivity and specificity of both enzymes as markers of metastatic disease were compared. In metastatic patients, enzyme activities were analyzed according to the site of metastases. RESULTS: Both alkaline phosphatase and GGT activities were normal in majority of patients with localized renal cell carcinoma and increased in most of the patients with metastatic disease (80% and 70%, respectively). GGT did not significantly differ from alkaline phosphatase in terms of sensitivity (70% vs 80%) and specificity (89% vs 92%). Concerning the site of metastases, high frequencies of increased GGT and alkaline phosphatase were found in patients with liver-only metastases (80% and 90%, respectively). All of the patients with both liver and bone metastases exhibited increased activity of both enzymes. Despite the fact that bone cells do not express GGT, increased activity was found in patients with bone metastases-only (45%), suggesting that enzymes might be released from tumor cells. CONCLUSIONS: Our data provided evidence that GGT is a sensitive marker of metastatic renal cell carcinoma. However, findings of abnormal GGT activity cannot specify the site of involvement.  相似文献   
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BACKGROUND: Paraoxonase-1 (PON1) is a high-density lipoprotein (HDL)-associated serum enzyme that protects lipoproteins from oxidative modifications. Polymorphisms in the gene, including PON1Q192R, have been studied. However, inconsistencies regarding the above-mentioned polymorphism obscure its association with vascular disease. METHODS: Using a two-substrate (paraoxon/diazoxon) activity method, we investigated the frequencies of PON1Q192R phenotypes in 261 middle-aged subjects: 156 patients with angiographically assessed coronary heart disease (CHD) and 105 CHD-free subjects as the control group. The PON1(192) phenotype was predicted from examination of the two-dimensional plot of hydrolysis rates of diazoxon vs. paraoxon and by using the antimode of the histogram of the ratio of diazoxonase/paraoxonase activity. RESULTS: The PON1Q192R phenotype frequencies in 113 patients with occlusion >50% (coronary artery disease-positive, CAD+ group) vs. control population were as follows: QQ (0.552 vs. 0.510), QR (0.382 vs. 0.408) and RR (0.066 vs. 0.082); chi2=0.414, p=0.813. We found lower paraoxonase (POase) and diazoxonase (DZOase) activities in the CAD+ patients when compared to the control population. According to logistic regression analysis, POase activity was a better predictor of coronary disease onset compared with DZOase activity measurements and PON1Q192R phenotyping. CONCLUSIONS: We conclude that enzyme activity (within a particular phenotypic group) is more important than phenotype alone in predicting susceptibility to coronary artery disease.  相似文献   
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