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71.
72.
Predominantly antibody deficiencies (PADs) encompass a heterogeneous group of disorders characterized by low immunoglobulin serum levels in the presence or absence of peripheral B cells. Clinical presentation of affected patients may include recurrent respiratory and gastrointestinal infections, invasive infections, autoimmune manifestations, allergic reactions, lymphoproliferation, and increased susceptibility to malignant transformation. In the last decades, several genetic alterations affecting B-cell development/maturation have been identified as causative of several forms of PADs, adding important information on the genetic background of PADs, which in turn should lead to a better understanding of these disorders and precise clinical management of affected patients. This review aimed to present a comprehensive overview of the known and potentially involved molecules in the etiology of PADs to elucidate the pathogenesis of these disorders and eventually offer a better prognosis for affected patients.  相似文献   
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74.
The pressure-volume relationship of the ferret gastric corpus was investigated to quantify the relative contributed of cholinergic and nonadrenergic, noncholinergic (NANC) mechanisms to the volume-accommodating property of this region. In splanchnectomized animals under control conditions the pressure-volume relationship of the corpus fitted a linear regression (Y = 0.30X + 0.57). Atropine decreased the magnitude of the pressure rise per unit volume, while after vagotomy this effect was reversed. The magnitude of these pressure changes in individual animals was consistent with reciprocal regulation of cholinergic and NANC pathways. Moreover, after vagotomy the shape of the pressure-volume curve was altered such that the pressure rise per unit volume was greater at the lower distending volumes. Continuous, low-frequency electrical vagal stimulation restored the pressure-volume relationship to that seen prior to vagotomy, an effect abolished by hexamethonium (25 mg/kg). Vasoactive intestinal polypeptide, on the other hand, caused a dose-related reduction in corpus pressure during the ramp increases in volume comparable to that seen during electrical stimulation but did not restore the shape of the pressure-volume curve. These data indicate that the action of the vagus may in part be permissive, with the sensitivity of local NANC pathways being modulated by a vagal cholinergic input.  相似文献   
75.
A scanning system for small animal imaging using non-contact, hybrid broadband diffuse optical spectroscopy (ncDOS) and diffuse correlation spectroscopy (ncDCS) is presented. The ncDOS uses a two-dimensional spectrophotometer retrieving broadband (610-900 nm) spectral information from up to fifty-seven source-detector distances between 2 and 5 mm. The ncDCS data is simultaneously acquired from four source-detector pairs. The sample is scanned in two dimensions while tracking variations in height. The system has been validated with liquid phantoms, demonstrated in vivo on a human fingertip during an arm cuff occlusion and on a group of mice with xenoimplanted renal cell carcinoma.OCIS codes: (170.0170) Medical optics and biotechnology, (170.0110) Imaging systems  相似文献   
76.

Purpose

This study aimed to determine effects of community-based healthy lifestyle education on the incidence of metabolic syndrome (MetS) in Tehranian children considering parental factors during a 13-year follow-up.

Methods

This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS) on 1603 healthy children, aged 8–18 years, who had complete parental data. Parental factors including MetS, education, age, occupation, and smoking were considered to distinguish parental clusters which could potentially predispose children to MetS. Lifestyle interventions were aimed at achieving healthy dietary patterns and increasing physical activity. Cluster analysis and survival Cox model were used to determine potential low and high risk parental clusters and the effect of intervention on the hazard of MetS in children respectively.

Results

In a model adjusted for children’s age and sex, the hazard of the MetS incidence was 36% higher in children from high-risk parental cluster than those from low-risk parental cluster (HR = 1.36, 95% CI = 1.07–1.73). Moreover, the intervention group showed a 39% lower risk for MetS incidence (HR = 0.61, 95% CI = 0.44–0.85) compared to controls, during the first 6 years after baseline assessment (short term), although the risk lowering effect of the intervention was not maintained long term.

Conclusion

A healthy lifestyle education was successful in reducing the short-term risk of MetS in children. To identify ways of maintaining long-term results, further research is definitely warranted.

Trial Registration

This study was funded by National Research Council and Planning and Management Organization and has been reviewed and approved by the Iranian registry of clinical trials (ISRCTN52588395).
  相似文献   
77.
78.
AIM: To improve our understanding of Iranian regional variation in Helicobacter pylori (H. pylori ) antibiotic resistance rates to find the best antibiotic therapy for eradication of H. pylori infections.METHODS: A total of 266 patients undergoing endoscopy in Shiraz, Southern Iran, were included in this study. H. pylori strains were isolated from antral biopsies by culture and confirmed by the rapid urease-test and gram staining. Antibiotic susceptibility of H. pylori isolates was determined by E-test.RESULTS: A total of 121 H. pylori strains were isolated, 50 from male and 71 from female patients. Data showed that 44% (n = 53), 20% (n = 24), 5% (n = 6), and 3% (n = 4) of all strains were resistant to the antibiotics metronidazole, amoxicillin, clarithromycin, and tetracycline, respectively. When the antibiotics were considered together we found 11 sensitivity patterns for the strains. Resistance to metronidazole was significantly higher in female than in male patients (P < 0.05). In about 71% of the metronidazole-resistant isolates, the minimum inhibitory concentrations (MICs) exceeded 256 μg/mL.CONCLUSION: We found a moderate rate of primary resistance to metronidazole. However, a high MIC (> 256 mg/L) which was found in 71% of the isolates is considerable. In the case of amoxicillin, an increased resistance rate of 20% is worrying. Resistance to clarithromycin and tetracycline is also emerging among the H. pylori strains in our region.  相似文献   
79.

Background and the purpose of the study

Natural products from plants have an important role in the development and production of new drugs mainly for cancer therapy. More recently, we have shown that the pericarp methanolic extract of Pistacia atlantica sub kurdica (with local name of Baneh) as a rich source of active biological components with high antioxidant and radical scavenging activities, has ability to cease proliferation and induce apoptosis in T47D human breast cancer cells. The present study aimed to clarify whether Baneh extract able to alter cell cycle progression of T47D cells or not.

Methods

In order to study the possible effect of Baneh extract on cell cycle of T47D cells, we evaluated cell cycle distribution and its regulatory proteins by flow cytometry and western blot analysis respectively.

Results

Baneh extract induced G0/G1 cell cycle arrest in conjunction with a marked decrease in expression of cyclin D1 and cdk4 that was strongly dependent on time of exposure. In parallel, Dox-treated T47D cells in early time points were accumulated on S phase, but after 48 h cell cycle progression was inhibited on G2/M. Dox promoted striking accumulation of cyclin B1 rapidly and enhanced cyclin A abundance.

Conclusion

Taken together, our results establish that the antitumor activity of the pericarp extract of Baneh partly is mediated via cell cycle arrest and downregulation of cyclin D1 and cdk4 expression. These findings warrant further evaluation regarding the mechanism(s) of action of this promising anticancer agent.  相似文献   
80.

Background

The prevalence of Pediatric Functional Constipation (FC) has been reported between 0.7% to 29.6%. This study was conducted to compare the laxative effect of cassia fistula emulsion (CFE) with mineral oil (MO) on FC. Cassia fistula is named in Traditional Iranian Medicine (TIM) as “Folus”.

Materials and methods

A randomized clinical trial was carried on 81 children (age range: 4–13 years) with FC, according to Rome III criteria in Amirkola Children’s Hospital, Babol, Iran. They received CFE or MO randomly for three weeks. CFE was produced according to the order of TIM references. Children were counted as improved when they exited from Rome III criteria of FC. Frequency of defecation, fecal incontinence, retentive posturing, severity of pain, consistency of stool and anal leakage of oily material were compared between the two groups and with baselines. An intent-to-treat analysis was used. Safety of drugs was assessed with the evaluation of clinical adverse effects.

Results

41 children were assigned randomly to receive CFE and 40 children received MO. After three weeks of medication, 84% of children in CFE group and 50% in MO group (p = 0.002) exited from the criteria of FC, so called improved. All measurable criteria improved in both groups. The frequency of defecation in CFE group improved from 1.7 per week (before the study) to 10.6 per week (at the third week) while this parameter differed in MO group from 2 to 6.1 (p < 0.001). The severity of pain during defecation and consistency of stool improved significantly better in CFE group than MO group (p < 0.05), but there were not any significant differences between the two groups in fecal incontinence and retentive posturing. Anal leakage of oily material occurred as an important complication in MO group while the children in CFE group did not complaint it. Drug’s compliances were not significantly different in the two groups. CFE and MO did not cause clinically significant side effects.

Conclusions

CFE was most effective than MO in the 3-week treatment of children with FC.  相似文献   
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