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1.
Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain.  相似文献   
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ObjectivesTo compare the amount of en-masse retraction with or without piezocision corticotomy, to assess the type of tooth movement, to evaluate root integrity after retraction, and to record reported pain levels.Materials and MethodsThis randomized, controlled clinical trial included 26 orthodontic patients requiring premolar extraction. The patients were divided into two groups: (1) an extraction with piezocision corticotomy group (PCG) and (2) an extraction-only group, which served as the control group (CG). Cone-beam computed tomography images were acquired before and 4 months after the initiation of en-masse retraction utilizing miniscrews. The following variables were assessed: the amount of en-masse retraction, incisor inclination, incisor and canine root resorption, and patient-reported pain.ResultsTwelve and 11 participants completed the entire study in the PCG and CG, respectively. The amount of en-masse retraction was significantly greater in the PCG compared to the CG (mean = 4.8 ± 0.57 mm vs 2.4 ± 0.33 mm, respectively [P < .001]). There was also significantly less tipping and root resorption of incisors in the PCG (P < .05). The reported pain was significantly higher on the first day in the PCG compared to the CG (P < .001); however, it became similar between the groups after 24 hours.ConclusionsPiezocision corticotomy enhanced the amount of en-masse retraction two times more with less root resorption. However, future studies are required to assess the long-term effects of this technique.  相似文献   
3.
The expression of interferon inducible genes are reported to be heightened in systemic lupus erythematosus (SLE); nevertheless, not much is known regarding the genetic variants underlying these genes and their role in the pathogenesis of disease. Herein, we aim to explore the potential association and contribution of polymorphisms in MX1 gene (i) promoter with part of exon 1 (ii) intron 6, and (iii) their resulting haplotypes, with susceptibility to SLE. A total of 306 subjects, 152 SLE and 154 healthy controls (HC), were screened by direct sequencing method. Statistical analysis was carried out using appropriate software. The screening region of interest in MX1 revealed the existence of promoter (?123C/A, ?88G/T, ?20 A/C) and intron 6 (+9862G/A, +10190G/A, +9901C/G, +9920C/A, +9959C/T, +10047A/G) variants in SLE and HC. A significant association was observed between MX1 ?88G/T SNP and susceptibility to SLE (χ 2?=?4.18, p?=?0.04, OR?=?1.89, 95 % CI 1.03–3.5). Haplotype analysis also revealed increased risk of SLE among individuals carrying CTA haplotype (?123 C, ?88 T, ?20 A) (χ 2?=?5.74, p?=?0.017, OR?=?4.28, 95 % CI 1.30–14.06). None of the other tested variants showed any significant association with SLE. The present study is the first to reveal the influence of genetic variation in MX1 gene in susceptibility to SLE.  相似文献   
4.
ObjectiveThe aim of the present study was to study the etiologies and patterns of maxillofacial fractures in patients treated in Riyadh City, Saudi Arabia, between 2007 and 2011.Patients and methodsData were obtained through a retrospective review of 237 patients admitted to the King Saud Medical City Dental Department with a diagnosis of maxillofacial trauma. After excluding patient files with incomplete or unclear records, and cases in which computed tomography showed no evidence of fracture, the files of 200 patients with a diagnosis of maxillofacial fracture were included in the study. For each case, patient’s sex and age, pattern of facial fractures, and cause of injury were recorded on a data sheet. The data were transferred to an SPSS (ver. 16.0; SPSS Inc., Chicago, IL, USA) spreadsheet for statistical analysis. The chi-square test was used to test the association between two categorical variables or factors (age group, cause) with p value set at p<0.05, and t-test value at <0.05 and independent.ResultsMotor vehicle accidents were the most common cause of maxillofacial fractures in most age groups, especially in males. Within the study sample, mandibular fractures were significantly more common than middle-third facial fractures (56.4% vs. 43.6%; p=0.006). Among mandibular fractures, parasymphyseal fractures were most common (47%), followed by condylar fractures (35.3%). Most (77.2%) middle-third facial fractures involved the zygomatic complex, and the incidence of such fractures differed significantly between male and female patients. p=0.72, not significant.ConclusionMales were more prone to maxillofacial fractures, perhaps as a result of the conservative nature of Saudi society, as the rules of Saudi Arabia do not allow the females to drive. Motor vehicle accidents were the most common cause of maxillofacial fractures in patients aged 10–29 years, indicating the high demand for the application of stricter traffic rules to reduce the rate of such accidents.  相似文献   
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The L‐arginine/NO pathway is an important regulator of pulmonary hypertension, the leading cause of mortality in patients with the chronic lung disease of prematurity, bronchopulmonary dysplasia. L‐arginine can be metabolized by NO synthase (NOS) to form L‐citrulline and NO, a potent vasodilator. Alternatively, L‐arginine can be metabolized by arginase to form urea and L‐ornithine, a precursor to collagen and proline formation important in vascular remodelling. In the current study, we hypothesized that C3H/HeN mice exposed to prolonged hyperoxia would have increased arginase expression and pulmonary vascular wall cell proliferation. C3H/HeN mice were exposed to 14 days of 85% O2 or room air and lung homogenates analyzed by western blot for protein levels of arginase I, arginase II, endothelial NOS (eNOS), ornithine decarboxylase (ODC), ornithine aminotransferase (OAT), and α‐smooth muscle actin (α‐SMA). Hyperoxia did not change arginase I or eNOS protein levels. However, arginase II protein levels were 15‐fold greater after hyperoxia exposure than in lungs exposed to room air. Greater protein levels of ODC and OAT were found in lungs following hyperoxic exposure than in room air animals. α‐SMA protein levels were found to be 7‐fold greater in the hyperoxia exposed lungs than in room air lungs. In the hyperoxia exposed lungs there was evidence of greater pulmonary vascular wall cell proliferation by α‐SMA immunohistochemistry than in room air lungs. Taken together, these data are consistent with a more proliferative vascular phenotype, and may explain the propensity of patients with bronchopulmonary dysplasia to develop pulmonary hypertension.  相似文献   
7.
Extensive evidence demonstrates that a hospital's organizational ownership structure impacts its overall performance, but little is known concerning the influence of hospital structure on the health of its community. This paper explores the association between US hospital referral region (HRR) health rankings and hospital ownership and performance. Data from the 2016 Commonwealth Fund Scorecard on Local Health System Performance, the American Hospital Association dataset, and the Hospital Value‐Based Purchasing dataset are utilized to conduct a cross‐sectional analysis of 36 quality measures across 306 HRRs. Multivariate regression analysis was used to estimate the association among hospital ownership, system performance measures—access and affordability, prevention and treatment, avoidable hospital use and cost, and healthy lives—and performance as measured by value‐based purchasing total performance scores. We found that indicators of access and affordability, as well as prevention and treatment, were significantly associated across all 3 hospitals' organizational structures. Hospital referral regions with a greater number of not‐for‐profit hospitals demonstrated greater indications of access and affordability, as well as better prevention and treatment rankings than for‐profit and government hospitals. Hospital referral regions with a greater number of government, nonfederal hospitals had worse scores for healthy lives. Furthermore, the greater the total performance scores score, the better the HRR score on prevention and treatment rankings. The greater the per capita income, the better the score across all 4 dimensions. As such, this inquiry supports the assertion that performance of a local health system is dependent on its community's resources of health care delivery entities and their structure.  相似文献   
8.
Introduction::Early intervention in patients with congenitally disconnected pulmonary artery improves long-term outcome.Case presentation::We present 3 cases of...  相似文献   
9.
Background:Camel urine (CU) has been used as traditional treatment in the Arabian Peninsula for centuries. Although, researchers have reported CU anti-cancer effects, the exact mechanism(s) of action involved has not been fully elucidated. The epithelial–mesenchymal transition EMT is a phenotypic switch that promotes the acquisition of a fibroblastoid-like morphology by epithelial tumor cells, resulting in enhanced tumor cell motility and invasiveness. EMT has been shown to contribute to metastasis and chemoresistance of carcinomas. For that, in the present study, we have assessed the potential mechanism (s) by which CU exert its anti-cancer effects and its possible synergistic therapeutic effect with Doxorubicin (DOX) in breast cancer cells. Methods:Determination of anti-proliferative and apoptosis validation of CU was performed by 3-(4,5-Dimethylthiazol-2-yl)-2,5,-diphenyltetrazolium bromide (MTT), annexin-V-fluorescein isothiocyanate assays, and Western blot. EMT protein markers, migration and invasion of cells were determined by Western blot or immunofluorescent staining, Scratch assay, Transwell invasion assay, respectively. Results:CU applied a significant anti-cancer effect on breast cancer cells via induction of DNA damage and apoptosis in a concentration- and time-dependent manner. Also, CU remarkably reversed the EMT by downregulating N-cadherin and Vimentin expression and upregulating E-cadherin expression. As a result, the stemness, migration and invasion of breast cancer cells were also inhibited, which was likely mediated by NF-κB-Snail signalling pathway and its downstream inflammatory effectors. CU successfully enhanced DOX cytotoxicity by reversing EMT which possibly through inhibition of NF-κB-Snail signalling and subsequently inflammation. Thus, our study provides new mechanistic bases for the therapeutic application of CU that may improve the outcomes of anti-cancer chemotherapy.Key Words: Chemoresistance, camel urine, breast cancer, NF-κB, EMT  相似文献   
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