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51.
Testicular torsion/detorsion is one of the important emergencies that requires fast surgical intervention. This study aimed to investigate the effects of Salvia miltiorrhiza hydroalcoholic extract combined with verapamil on testicular ischaemia/reperfusion damage in Wistar albino rats. All animals were distributed in 3 groups (n = 8), including the sham-operated group, torsion/detorsion (TD) group and torsion/detorsion + pretreatment with 200 mg/kg Salvia miltiorrhiza extract combined with 0.3 mg/kg verapamil (SMV) group. Oxidative stress biomarkers (MDA, GPx, CAT and TAC) both in plasma and testicular tissue, sperm parameters (motility, vitality, concentration and morphology) and histopathological parameters (MSTD, GECT, Johnson's score, Cosentino's score and testicular cell thickness) were assessed in all groups. Ischaemia/reperfusion significantly increased MDA and decreased GPx, CAT and TAC levels (p < .05). Pretreatment with SMV significantly increased GPx, CAT and TAC levels (p < .05). SMV group increased progressive sperm motility and vitality and reduced non-progressive motility of spermatozoon (p < .05). Testicular torsion significantly decreased all histopathological parameters compared to the sham group (p < .05). SMV pretreatment remarkably increased MSTD, GECT and Cosentino's score in comparison with the TD group (p < .05). A combination of Salvia miltiorrhiza with verapamil could reduce damages triggered by testicular torsion detorsion and improve sperm functionality parameters and oxidative stress defence systems.  相似文献   
52.

Background

Entamoeba moshkovskii and E. dispar are impossible to differentiate microscopically from the pathogenic species E. histolytica. Multiplex polymerase chain reaction (Multiplex PCR) is a widespread molecular biology technique for amplification of multiple targets in a single PCR experiment.

Methods

For detection and differentiation of the three-microscopy indistinguishable Entamoeba species in human, multiplex PCR assay using different DNA extraction methods was studied. A conserved forward primer was derived from the middle of the small-subunit rRNA gene, and reverse primers were designed from signature sequences specific to each of these three Entamoeba species.

Results

A 166-bp PCR product with E. histolytica DNA, a 580-bp product with E. moshkovskii DNA and a 752-bp product with E. dispar DNA were generated in a single-round and multiplex PCR reaction.

Conclusion

We recommend this PCR assay as an accurate, rapid, and effective diagnostic method for the detection and discrimination of these three Entamoeba species in both routine diagnosis of amoebiasis and epidemiological surveys.  相似文献   
53.
Background

Weight regain (WR) and insufficient weight loss (IWL) after sleeve gastrectomy (SG) are challenging issues. This study aimed to evaluate the predictors of WR and IWL after SG.

Methods

In this retrospective analytical study, 568 patients who underwent SG at Hazrat-e Rasool General Hospital, Tehran, Iran, between January 2015 and April 2022 were evaluated. A total of 333 patients were included. WR and IWL were evaluated by multiple criteria such as a BMI of > 35 kg/m2, an increase in BMI of > 5 kg/m2 above nadir, an increase in weight of > 10 kg above nadir, percentage of excess weight loss (%EWL) < 50% at 18 months, an increase in weight of > 25% of EWL from nadir at 36 months, and percentage of total weight loss (%TWL) < 20% at 36 months. All participants were followed up for 36 months.

Result

The univariate analysis showed that preoperative BMI, obstructive sleep apnea, metformin consumption, and grades 2 and 3 fatty liver disease were associated with WR and IWL (P < 0.05). WR or IWL incidence varied (0–19.3%) based on different definitions. The multivariate analysis showed that a preoperative BMI of > 45 kg/m2 [odds ratioAdjusted (ORAdj) 1.77, 95% CI: 1.12–4.11, P = 0.038] and metformin consumption [ORAdj: 0.48, 95% CI: 0.19–0.78, P = 0.001] were associated with WR and IWL after SG, regardless of the definition of WR or IWL.

Conclusion

This study showed that preoperative BMI of > 45 kg/m2, obstructive sleep apnea, metformin consumption, and grades 2 and 3 of fatty liver disease were associated with WR or IWL.

Graphical abstract
  相似文献   
54.
Controversial immunomodulatory properties of bee venom (BV) have provided an appropriate field for more investigation. The aim of present research was to verify the effects of honeybee venom on matrix metalloproteinase activity and interferon production as well as cell proliferation in monocyte and fibroblast cell lines.The monocyte and fibroblast cell lines (K562, HT-1080, WEHI-164) were used in order to assess proliferative response, interferon-1 production and matrix metalloproteinase-2 (MMP-2) activity. Australian BV (ABV) and Iranian BV (IBV) preparations at concentrations of 0.025, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, and 1microg/ml were added to each overnight cultured cells. In time course study, cells were treated each with ABV and IBV. In all cases supernatants were collected 24 hours after treatment. A sample of the each medium was used for zymography and interferons assay. Non-treated cells were used as controls.The production of IFN-a and IFN-b in supernatant of cell cultures was assessed using enzyme linked immunoassay procedure. MMP-2 activity, as an inflammatory index, was evaluated using zymoanalysis method.The results of this study showed that, there were no significant difference between two sources of honey bee venoms when they were added to an identical cell line, whereas, the responses of various cell lines against bee venom were different. The increasing amounts of bee venom to human monocyte cell line (K562) revealed a significant increase in proliferative response. Our findings showed that the bee venom had no influence on IFN-a production in cell culture media, whereas, adding the BV to K562 cell line could significantly increase the production level of IFN-b only on day 8 post-treatment. In addition the effect of bee venom on MMP-2 activity in both cell culture media, WEHI-164 and K562 was similar. The stimulatory effect of bee venom on MMP-2 activity occurred at low doses. In contrast, its inhibitory effect was seen at high concentrations.It is concluded that, honeybee venom affects on MMP-2 activity and interferon beta production as well as cell proliferation in a time and dose-dependent manner.  相似文献   
55.
Patients with human immunodeficiency virus (HIV) infection are at increased risk for developing lymphoproliferative disorders. Multicentric Castleman's disease should always be kept in the differential diagnosis of HIV-positive patients suspected of having lymphoma to avoid misdiagnosis. We report the case of a 40-year-old HIV-positive homosexual man who presented with lower back pain and features highly suggestive of lymphoma including lymphadenopathy, elevated lactic dehydrogenase, and splenomegaly. The patient's plasma was positive by polymerase chain reaction for Kaposi sarcoma herpesvirus/human herpesvirus-8 (KSHV/ HHV8), and a lymph node biopsy revealed Multicentric Castleman's disease. He was started on highly active antiretroviral therapy, corticosteroids, valganciclovir, and rituximab. His back pain subsided, lymphadenopathy regressed, and he became KSHV/HHV8 negative. Albeit a rare condition, Castleman's disease should always be considered in immunocompromised patients suspected of having lymphoma.  相似文献   
56.
Signal transduction networks can be perturbed biochemically, genetically, and pharmacologically to unravel their functions. But at the systems level, it is not clear how such perturbations are best implemented to extract molecular mechanisms that underlie network function. Here, we combined pairwise perturbations with multiparameter phosphorylation measurements to reveal causal mechanisms within the signaling network response of cardiomyocytes to coxsackievirus B3 (CVB3) infection. Using all possible pairs of six kinase inhibitors, we assembled a dynamic nine-protein phosphorylation signature of perturbed CVB3 infectivity. Cluster analysis of the resulting dataset showed repeatedly that paired inhibitor data were required for accurate data-driven predictions of kinase substrate links in the host network. With pairwise data, we also derived a high-confidence network based on partial correlations, which identified phospho-IκBα as a central “hub” in the measured phosphorylation signature. The reconstructed network helped to connect phospho-IκBα with an autocrine feedback circuit in host cells involving the proinflammatory cytokines, TNF and IL-1. Autocrine blockade substantially inhibited CVB3 progeny release and improved host cell viability, implicating TNF and IL-1 as cell autonomous components of CVB3-induced myocardial damage. We conclude that pairwise perturbations, when combined with network-level intracellular measurements, enrich for mechanisms that would be overlooked by single perturbants.  相似文献   
57.
Primary drug resistance is a major problem in multiple myeloma, an incurable disease of the bone marrow. Cell adhesion-mediated drug resistance (CAM-DR) causes strong primary resistance. By coculturing multiple myeloma cells with bone marrow stromal cells (BMSCs), we observed a CAM-DR of about 50% to melphalan, treosulfan, doxorubicin, dexamethasone, and bortezomib, which was not reversed by secreted soluble factors. Targeting the adhesion molecules lymphocyte function-associated antigen 1 (LFA-1) and very late antigen 4 (VLA-4) by monoclonal antibodies or by the LFA-1 inhibitor LFA703 reduced CAM-DR significantly. Only statins such as simvastatin and lovastatin, however, were able to completely restore chemosensitivity. All these effects were not mediated by deadhesion or reduced secretion of interleukin 6. Targeting geranylgeranyl transferase (GGTase) and Rho kinase by specific inhibitors (GGTI-298 and Y-27632), but not inhibition of farnesyl transferase (FTase) by FTI-277, showed similar reduction of CAM-DR. Addition of geranylgeranyl pyrophosphate (GG-PP), but not of farnesyl pyrophosphate (F-PP), was able to inhibit simvastatin-induced CAM-DR reversal. Our data suggest that the 3-hydroxy-3-methylglutaryl-coenzyme-A (HMG-CoA)/GG-PP/Rho/Rho-kinase pathway mediates CAM-DR and that targeting this pathway may improve the efficacy of antimyeloma therapies by reduction of CAM-DR.  相似文献   
58.
Overweight and obese patients with osteoarthritis (OA) experience more OA pain and disability than patients who are not overweight. This study examined the long-term efficacy of a combined pain coping skills training (PCST) and lifestyle behavioral weight management (BWM) intervention in overweight and obese OA patients. Patients (n=232) were randomized to a 6-month program of: 1) PCST+BWM; 2) PCST-only; 3) BWM-only; or 4) standard care control. Assessments of pain, physical disability (Arthritis Impact Measurement Scales [AIMS] physical disability, stiffness, activity, and gait), psychological disability (AIMS psychological disability, pain catastrophizing, arthritis self-efficacy, weight self-efficacy), and body weight were collected at 4 time points (pretreatment, posttreatment, and 6 months and 12 months after the completion of treatment). Patients randomized to PCST+BWM demonstrated significantly better treatment outcomes (average of all 3 posttreatment values) in terms of pain, physical disability, stiffness, activity, weight self-efficacy, and weight when compared to the other 3 conditions (Ps<0.05). PCST+BWM also did significantly better than at least one of the other conditions (ie, PCST-only, BWM-only, or standard care) in terms of psychological disability, pain catastrophizing, and arthritis self-efficacy. Interventions teaching overweight and obese OA patients pain coping skills and weight management simultaneously may provide the more comprehensive long-term benefits.  相似文献   
59.

Objective

Obesity and joint injury are primary risk factors for osteoarthritis (OA) that involve potential alterations in the biomechanical and inflammatory environments of the joint. Posttraumatic arthritis is a frequent long‐term complication of intraarticular fractures. Obesity has been linked to primary OA and may potentially contribute to the development of posttraumatic arthritis by a variety of mechanisms. The objectives of this study were to determine whether diet‐induced obesity influences the severity of posttraumatic arthritis in mice and to examine the interrelationships between joint degeneration and serum levels of the inflammatory cytokines and adipokines that are involved in this response.

Methods

C57BL/6 mice were fed either normal chow (13% fat) or a high‐fat diet (60% fat) starting at 4 weeks of age. At 16 weeks of age, half of the mice in each group were subjected to a closed intraarticular fracture of the left knee. At 8 weeks postfracture, knee OA was assessed by cartilage and synovium histology in addition to bone morphology. Serum cytokine concentrations were determined with multiplex assays.

Results

Fractured knee joints of mice receiving a high‐fat diet showed significantly increased OA degeneration compared with nonfractured contralateral control knees, while fractured knee joints of mice receiving a low‐fat diet did not demonstrate significant differences from nonfractured contralateral control knees. A high‐fat diet increased serum concentrations of interleukin‐12p70 (IL‐12p70), IL‐6, and keratinocyte‐derived chemokine while decreasing adiponectin concentrations. Joint injury also increased IL‐12p70 concentrations in mice receiving a high‐fat diet. Systemic levels of adiponectin were inversely correlated with synovial inflammation in control limbs.

Conclusion

Diet‐induced obesity significantly increased the severity of OA following intraarticular fracture. Obesity and joint injury together can alter systemic levels of inflammatory cytokines such as IL‐12p70.
  相似文献   
60.
The development of regenerative therapies for cartilage injury has been greatly aided by recent advances in stem cell biology. Induced pluripotent stem cells (iPSCs) have the potential to provide an abundant cell source for tissue engineering, as well as generating patient-matched in vitro models to study genetic and environmental factors in cartilage repair and osteoarthritis. However, both cell therapy and modeling approaches require a purified and uniformly differentiated cell population to predictably recapitulate the physiological characteristics of cartilage. Here, iPSCs derived from adult mouse fibroblasts were chondrogenically differentiated and purified by type II collagen (Col2)-driven green fluorescent protein (GFP) expression. Col2 and aggrecan gene expression levels were significantly up-regulated in GFP+ cells compared with GFP− cells and decreased with monolayer expansion. An in vitro cartilage defect model was used to demonstrate integrative repair by GFP+ cells seeded in agarose, supporting their potential use in cartilage therapies. In chondrogenic pellet culture, cells synthesized cartilage-specific matrix as indicated by high levels of glycosaminoglycans and type II collagen and low levels of type I and type X collagen. The feasibility of cell expansion after initial differentiation was illustrated by homogenous matrix deposition in pellets from twice-passaged GFP+ cells. Finally, atomic force microscopy analysis showed increased microscale elastic moduli associated with collagen alignment at the periphery of pellets, mimicking zonal variation in native cartilage. This study demonstrates the potential use of iPSCs for cartilage defect repair and for creating tissue models of cartilage that can be matched to specific genetic backgrounds.  相似文献   
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