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101.

Objective

To determine the better approach for weaning preterm infants from nasal continuous positive airway pressure (NCPAP) with or without transitioning to nasal cannula (NC).

Design/methods

This is a randomized, open label, controlled trial. Preterm infants born at ≥ 28 weeks gestation who were clinically stable on NCPAP of 5 cm H2O with FiO2 < 0.30 for at least 24 h were randomly assigned to one of 2 groups. The no-NC group were kept on NCPAP until they were on FiO2 = 0.21 for 24 h, and then were weaned off NCPAP completely without any exposure to NC. If they met failing criteria, NCPAP was re-instituted. The NC-group was weaned off NCPAP when FiO2 was ≤ 0.30 to NC (2 L/min) followed by gradual weaning from oxygen. Infants who failed NC were supported back with NCPAP for 24 h before making a second attempt of NC.

Results

Sixty neonates were enrolled; 30 in each group. The two groups were similar in birthweight, gestational age, sex, antenatal steroids, mode of delivery, use of surfactant and xanthines, and duration of mechanical ventilation. After randomization, the no-NC group had fewer days on oxygen [median (interquartile range): 5 (1-8) vs 14 (7.5-19.25) days, p < 0.001] and shorter duration of respiratory support [10.5 (4-21) vs 18 (11.5-29) days, p = 0.03]. There were no differences between groups regarding success of weaning from NCPAP.

Conclusions

Weaning preterm infants from NCPAP to NC is associated with increased exposure to oxygen and longer duration of respiratory support.  相似文献   
102.
Aberrant activation of the Wnt signalling pathway is a key feature of many cancers. β-Catenin, adenomatous polyposis coli (APC) and E-cadherin are major players in this pathway. The aim of this study is to examine the expression of β-catenin, APC and E-cadherin in tumour tissues of 80 Tunisian patients with gastric carcinoma and to determine the methylation status of the APC promoter in tumour tissues. Associations between protein expression and clinico-pathological parameters, including prognosis, were performed. Positive expression of β-catenin, APC and E-cadherin was observed in 77.5, 68.7 and 60 % of cases, respectively. Tumours lacking membranous expression of β-catenin had greater extent of lymph node metastasis, poor differentiation and advanced T-stage. The expression of E-cadherin correlated with poor differentiation (P?=?0.05) and β-catenin expression (P?=?0.004). With regards to prognosis, the overall survival time was significantly prolonged for patients showing normal β-catenin expression (exclusively or predominantly membranous staining) alone or combined with positive APC expression (P log rank?=?0.008 and 0.003, respectively). The methylated pattern of APC promoter 1A was detected in 43.8 % of cases and correlated with T-stage (P?=?0.046) and distant metastasis (P?=?0.037). No correlation was found between the methylated profile of APC promoter 1A and the expression of APC protein in tumour tissues. Our findings suggest that deregulation of the Wnt pathway via abnormal expression of β-catenin and E-cadherin occurred frequently in gastric carcinoma and correlated with worse clinical behaviour.  相似文献   
103.
We report one case of congenital cystic adenomato?d malformation of the lung (C.A.A.M.) diagnosed at 24 weeks of gestation with cocommitant fetal hydraps. The diagnosis of (C.A.A.M.) type I was confirmed histologically.  相似文献   
104.
Isoniazid is a first line antituberculosis drug metabolized mainly in the liver by the Nacetyltransferase. There are differences between individuals in acetylation metabolism. Subjects are thereby characterized as being rapid or slow acetylators. The purpose is to study the distribution pattern of acetylation in patients with tuberculosis followed up at the teaching Hospital of La Rabta. The determination of acetylator phenotype was carried out on 620 tuberculosis patients during a period of 12 years. There were 483 men and 137 women with a median age of 40.3 years. The test was investigated before drug regimen administration at the dose of 5 mg/kg. A blood sample was taken three hours after the first administration. The determination of acetylation profile was worked out by Vivien hypothesis. In our population 391 were low and 229 were fast acetylators. The median dose recommended within the test was 3.04 mg/kg/day. 56% of our patients were initially receiving high dose of isoniazid. An increase in serum transaminase was initially observed in 60 patients among whom 47 slow acetylators. After dose adaptation, 53 patients had improved their biological abnormalities. The majority of Tunisian population seem to belong to slow acetylators modal. The frequency of hepatotoxicity suggests reducing the recommended dose of isoniazid from 5 to 3 mg/kg/day.  相似文献   
105.
The goal of this study was to evaluate the COG Monte Carlo radiation transport code, developed and tested by Lawrence Livermore National Laboratory, for neutron capture therapy related modeling. A boron neutron capture therapy model was analyzed comparing COG calculational results to results from the widely used MCNP4B (Monte Carlo N-Particle) transport code. The approach for computing neutron fluence rate and each dose component relevant in boron neutron capture therapy is described, and calculated values are shown in detail. The differences between the COG and MCNP predictions are qualified and quantified. The differences are generally small and suggest that the COG code can be applied for BNCT research related problems.  相似文献   
106.
Abstract Objectives:   To evaluate our experience in the management of patients with major blunt renal trauma treated at a major urban trauma center during the last ten years. Patients and Methods:   The medical records of 72 patients with major blunt renal lacerations treated from 1998 to 2008 were reviewed retrospectively. Patients were broken down into two groups based on whether they were managed conservatively (group 1) or surgically (group 2). Each group was compared with respect to the initial evaluation, computerized tomography findings, associated injuries, hospital stay, transfusion requirements, nephrectomy rate, complications and follow-up imaging. Results:   There were 57 patients with grade IV and 15 patients with grade V renal injuries. Of these, 51 (70.8%) patients were managed conservatively (48 with grade IV and 3 with grade V) and 21 (29.2%) patients were managed surgically (9 with grade IV and 12 with grade V). Patients in group 1 had significantly lower transfusion requirements (3.1 vs. 7.5 units, p < 0.0001), shorter hospital stays (11.8 vs. 15.9 days p < 0.003) and fewer complications (21.6 vs. 76.1%, p < 0.001). No death was observed in group 1, while three in group 2 died of major associated injuries. All surviving patients had significant resolution of the extravasation before hospital discharge. Conclusions:   Our data supports the conservative management of grade IV blunt renal parenchymal injuries in the absence of hemodynamic instability of renal origin. Even select patients with grade V parenchymal injuries can undergo a trial of conservative management.  相似文献   
107.
108.
We previously reported that infection of BALB/c mice with the parasite Plasmodium chabaudi induces high production of natural autoantibodies. Here we demonstrate that such an infection of lupus-prone (NZB × NZW)F1 (B/W) mice retards the development of their autoimmune disease. Survival and disease hallmarks (high-grade proteinuria and IgG anti-DNA antibodies) were delayed for 6 months when parasite inoculation was given at either 3 or 7 months of age, i.e. before or after the onset of the clinical symptoms. Similar beneficial effects, although less pronounced, were obtained when mice were treated with a total of 800 m?g of IgG (P-IgG) or IgM (P-IgM) or 300 m?g of cryoglobulin preparations isolated from P. chabaudi-infected BALB/c mice while similarly prepared fractions from uninfected mice had little effect. Compared to these fractions, P-IgG and P-IgM contained higher levels of natural antibodies bearing the D23 idiotype characteristic of polyreactive natural autoantibodies with enhanced activity against Fab and Fc fragments of IgG. In surviving mice, the level of anti-DNA antibodies, particularly those of IgG1 isotype, were significantly decreased. Flow cytometric analysis of various T cell subsets showed that the number of cells expressing γδ T cell receptor (TcR) antigens which did not vary with age was not modified after P-IgG or P-IgM treatment. In contrast, the number of T cells expressing Vβ8.1,2, Vβ10 and Vβ14 TcR antigens, which increased with age, were significantly reduced. Taken together, these results indicate that parasite infection of mice induces the synthesis of populations of IgM and IgG natural autoantibodies with immunoregulatory properties and that these antibodies attempt, at least transitorily, to rescue a natural autoantibody network that is deficient in B/W mice.  相似文献   
109.
Brain lesions induced in newborn mice or rats by the glutamatergic agonists ibotenate (acting on NMDA and metabotropic receptors) or S-bromowillardiine (acting on AMPA-kainate receptors) mimic some aspects of white matter cysts and transcortical necrosis observed in human perinatal brain damage associated with cerebral palsy. Exogenous and endogenous cannabinoids have received increasing attention as potential neuroprotective agents in a number of neurodegenerative disorders of the adult. One recent study showed neuroprotection by the cannabinoid agonist WIN-55212 in a newborn rat model of acute severe asphyxia. The present study was designed to assess the neuroprotective effects of the endogenous cannabinoid anandamide using a well-defined rodent model of neonatal excitotoxic brain lesions. In this model, anandamide provided dose-dependent and long-lasting protection of developing white matter and cortical plate reducing the size of lesions induced by S-bromowillardiine. Anandamide had only marginal neuroprotective effect against ibotenate-induced cortical grey matter lesions. Anandamide-induced neuroprotection against AMPA-kainate receptor-mediated brain lesions were blocked by a CB1 antagonist but not by a CB2 antagonist. Furthermore, anandamide effects were mimicked by a CB1 agonist but not by a CB2 agonist. Real-time PCR confirmed the expression of CB1 receptors, but not CB2 receptors, in the untreated newborn neocortex. Finally, neuroprotective effects of anandamide in white matter involved increased survival of preoligodendrocytes and better preservation of myelination. The present study provides experimental support for the role of endocannabinoids as a candidate therapy for excitotoxic perinatal brain lesions.  相似文献   
110.

Objective

To determine the diagnostic value of mean apparent diffusion coefficient (ADC) measures to distinguish between benign (grade I) and atypical (grade II) cranial meningiomas.

Patients and methods

Forty-seven patients (10 men and 37 women) with cranial meningiomas were included in the study and underwent MRI examination including diffusion-weighted imaging (DWI). Signal characteristics on conventional MR and diffusion-weighted images were evaluated. The intratumoral mean ADC values were obtained and correlated with the final histopathological findings of the excised tumors. The optimum cutoff value of mean ADC measurements to differentiate between grade I and II was determined using the generated receiver operating characteristic (ROC)

Results

Thirty-six meningiomas were benign (WHO grade I), while 11 were atypical (grade II). No grade III meningiomas were encountered during the study period. At standard MRI sequences, only the enhancement pattern had produced a significant statistical correlation with the tumoural grade (p?=?0.001). Tumoural margins, peritumoural edema, and the DWI signal showed none statistical relationship (p?=?0.105, 0.11 and 0.219 respectively). Intratumoral mean ADC values were significantly lower in grade II meningiomas (p?<?0.001). The mean ADC value was 1.02?±?0.16?×?10?3?mm2/s for grade I meningiomas and 0.72?±?0.09?×?10?3?mm2/s?1 for grade II. According to the generated receiver operating curve (ROC), we determined a threshold of 0.79?×?10?3?mm2/s?1 to produce the best diagnostic performance to distinguish between grade I and II meningiomas (sensitivity 81.2%, specificity 91.7% and accuracy 89.3%). The positive and negative predictive values were 75% and 94.3%.

Conclusion

The intratumoral mean ADC measurement provides a discriminative feature to discriminate between benign (grade I) and atypical (Grade II) cranial meningiomas.  相似文献   
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