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121.
122.
Past research has indicated that child abuse is related to mental and physical health conditions and that mental and physical health conditions are related to decreased health-related quality of life (HRQOL). However, little is known about the independent relationship between child abuse and HRQOL. For the current analysis, data were from the nationally representative Netherlands Mental Health Survey and Incidence Study. Multiple linear regression analyses tested the relationships between child abuse and current HRQOL (SF-36) after adjusting for the effects of sociodemographic variables and numerous psychiatric disorders and physical health conditions. Neglect, psychological abuse, physical abuse, severe sexual abuse, and number of types of child abuse experienced were associated with reduced mental HRQOL. Psychological abuse, physical abuse, and number of types of child abuse experienced were associated with reduced physical HRQOL. Child abuse is an important determinant of HRQOL. The ability to successfully reduce the occurrence of child abuse or provide early intervention after child abuse occurs may help to improve HRQOL in the general population.  相似文献   
123.
Several studies have suggested that there may be an increased prevalence of affective disorders in people with motor neuron disease (MND). However, the literature is inconsistent, possibly because of small sample sizes in the existing studies. The Canadian province of Alberta has a universal health care system in which physician contacts are recorded along with ICD-9-CM diagnostic codes. In this analysis, diagnostic codes indicative of MND and affective disorders were used. Stratified analysis and logistic regression were used in the analysis. There were 336 cases of MND leading to a prevalence of 14.5 per 100,000 in provincial residents > or =20 years old. Affective disorders were identified in 8.6% of the total population during the same year. The crude odds ratio for affective disorders in MND was 2.3 (95% CI = 1.7-3.0). However, the prevalence of affective disorders declined with increasing illness duration.  相似文献   
124.
CONTEXT: Although military personnel are trained for combat and peacekeeping operations, accumulating evidence indicates that deployment-related exposure to traumatic events is associated with mental health problems and mental health service use. OBJECTIVE: To examine the relationships between combat and peacekeeping operations and the prevalence of mental disorders, self-perceived need for mental health care, mental health service use, and suicidality. DESIGN: Cross-sectional, population-based survey. SETTING: Canadian military. PARTICIPANTS: A total of 8441 currently active military personnel (aged 16-54 years). MAIN OUTCOME MEASURES: The DSM-IV mental disorders (major depressive disorder, posttraumatic stress disorder, generalized anxiety disorder, panic disorder, social phobia, and alcohol dependence) were assessed using the World Mental Health version of the World Health Organization Composite International Diagnostic Interview, a fully structured lay-administered psychiatric interview. The survey included validated measures of self-perceived need for mental health treatment, mental health service use, and suicidal ideation. Lifetime exposure to peacekeeping and combat operations and witnessing atrocities or massacres (ie, mutilated bodies or mass killings) were assessed. RESULTS: The prevalences of any past-year mental disorder assessed in the survey and self-perceived need for care were 14.9% and 23.2%, respectively. Most individuals meeting the criteria for a mental disorder diagnosis did not use any mental health services. Deployment to combat operations and witnessing atrocities were associated with increased prevalence of mental disorders and perceived need for care. After adjusting for the effects of exposure to combat and witnessing atrocities, deployment to peacekeeping operations was not associated with increased prevalence of mental disorders. CONCLUSIONS: This is the first study to use a representative sample of active military personnel to examine the relationship between deployment-related experiences and mental health problems. It provides evidence of a positive association between combat exposure and witnessing atrocities and mental disorders and self-perceived need for treatment.  相似文献   
125.
Large-scale changes (gross chromosomal rearrangements [GCRs]) are common in genomes, and are often associated with pathological disorders. We report here that a specific pair of nearby inverted repeats in budding yeast fuse to form a dicentric chromosome intermediate, which then rearranges to form a translocation and other GCRs. We next show that fusion of nearby inverted repeats is general; we found that many nearby inverted repeats that are present in the yeast genome also fuse, as does a pair of synthetically constructed inverted repeats. Fusion occurs between inverted repeats that are separated by several kilobases of DNA and share >20 base pairs of homology. Finally, we show that fusion of inverted repeats, surprisingly, does not require genes involved in double-strand break (DSB) repair or genes involved in other repeat recombination events. We therefore propose that fusion may occur by a DSB-independent, DNA replication-based mechanism (which we term “faulty template switching”). Fusion of nearby inverted repeats to form dicentrics may be a major cause of instability in yeast and in other organisms.  相似文献   
126.
The integrin α6β1 and its main ligand laminin-111 are overexpressed in glioblastoma, as compared with normal brain tissue, suggesting they may be involved in glioblastoma malignancy. To address this question, we stably expressed the α6 integrin subunit in the U87 cell line via retroviral-mediated gene transfer. We show that cell surface expression of the α6β1 integrin led to dramatic changes in tumor U87 cell behavior, both in vitro and in vivo. Nude mice receiving either subcutaneous or intracerebral inoculation of α6β1-expressing cells developed substantially more voluminous tumors than mice injected with control cells. The difference in tumor growth was associated with a marked increase in vascularization in response to α6β1 integrin expression and may also be related to changes in the balance between cell proliferation and survival. Indeed, expression of α6β1 enhanced proliferation and decreased apoptosis of U87 cells both in the tumor and in vitro. Additionally, we demonstrate that α6β1 is implicated in glioblastoma cell migration and invasion and that laminin-111 might mediate dissemination of α6β1-positive cells in vivo. Our results highlight for the first time the considerable role of the integrin α6β1 in glioma progression.Malignant brain tumors have an increasing incidence in both children and adults. In adults, the most common type of primary brain tumor, malignant glioma, is considered as one of the deadliest of human cancers. Despite recent advances in both diagnostic modalities and therapeutic strategies, the 5-year survival rate of less than 3% in patients with glioblastoma is among the lowest for all cancers.1 Patients with the most malignant histopathological subtype, glioblastoma, carry the worst prognosis, with median survival rate of less than 1 year, despite aggressive surgery associated with adjuvant radiotherapy and chemotherapy.1 Glioblastoma are characterized by rapidly dividing cells, high degree of vascularity, invasion into normal brain tissue, and an intense resistance to death-inducing stimuli.2,3 Since integrins, the major family of extracellular matrix (ECM) receptors, are involved in these events, they are one of the most promising molecules to consider for a targeted therapy.Integrins are cell surface transmembrane αβ heterodimers that recognize specific ECM ligands. The combination of α and β subunits, leading to the formation of at least 24 receptors, determines the ligand specificity.4 Glioblastoma commonly displays enhanced expression of several integrins along with their ECM ligands: αvβ3 and αvβ5 (tenascin and vitronectin receptors), α5β1 (fibronectin receptor), α2β1 (collagens receptor), and α3β1, α6β4, and α6β1 (laminins receptors).5 Numerous studies have focused on the αv integrin family. The integrins αvβ3 and αvβ5 are markers of glioblastoma malignancy6 and influence a variety of processes in glioblastoma progression in vivo, including proliferation, apoptosis, and angiogenesis.7 Furthermore, cilengitide, an αvβ3 and αvβ5 integrins antagonist, extends mouse survival by delaying the tumor growth8,9 and is nowadays in clinical trial for recurrent malignant glioma. Two other integrins, α5β1 and α3β1, have been shown to be implicated in glioma cell adhesion and migration in vitro.10,11 In addition, the use of α5β1 antagonists reduces glioma cell proliferation in vitro,10 while α3β1 antagonists inhibited glioma invasion in vivo.11The α6 integrin subunit associates with β1 or β4 subunits to form functional heterodimers that selectively bind laminins. The α6β4 integrin is essential for the organization and maintenance of epithelial hemidesmosomes that link the intermediate filaments with the extracellular matrix.12 The major ligand of α6β4 is the laminin-332, while α6β1 is a well-characterized laminin-111 receptor. Overexpression of α6β1 integrin has been associated with the progression of many epithelial tumors. In particular, induction of α6β1 expression is an early event in hepatocellular carcinogenesis.13,14 In the same way, during prostate cancer progression α6β1 is continually expressed and found in micrometastases.15 Expression of α6β1 integrin has also been linked to metastatic potential of melanoma cells,16 and has been involved in the survival and metastatic potential of human breast carcinoma cells.17,18 Moreover, in a recent study using the α6-blocking antibody GoH3, Lee et al19 inhibited angiogenesis and breast carcinoma growth in vivo.Several studies concerning gliomas and the α6β1 ligand laminin-111 have been reported in the literature. Using immunohistochemistry studies, Gingras et al20 showed that α6 integrin was strongly expressed in glioblastoma tissue, whereas it was weakly expressed in normal brain. Previtali et al21 confirmed that the expression of α6 was increased in glioblastoma and in other central nervous system tumors, such as meningioma, astrocytoma, and neuroblastoma, when compared with the autologous normal tissue counterpart. In glioblastoma biopsies, laminin-111 is highly expressed on tumor blood vessels, but also within the brain tumor as punctuate deposits and at the tumor invasion front.22 In vitro, glioma cells can both secrete laminin-111 and induce its expression in normal brain tissue.22,23,24 Moreover, laminin-111 is one of the most permissive substrates for adhesion and migration of glioma cells in vitro.25,26,27 Additionally, over laminin-111, migrating glioma cells are protected from apoptosis.28 For all these reasons, we hypothesized that laminin-111 and its main receptor α6β1 may contribute to glioblastoma progression.In the present study we investigated the role of integrin α6β1 in glioblastoma malignancy by using U87, a well-characterized glioblastoma cell line. We report that stable expression of α6β1 in this α6-negative cell line leads to enhanced tumor progression and tumor growth in vivo. We demonstrate that α6β1 is pro-angiogenic and acts on the balance between proliferation and apoptosis. Additionally, we show that α6β1 is involved in glioblastoma cell migration and invasion. Our results highlight for the first time the considerable role of integrin α6β1 in the malignant phenotype of glioblastoma cells and demonstrate that the α6β1-expressing cell is an appropriate model for the study of glioblastoma progression.  相似文献   
127.

Ethnopharmacological relevance

Achillea santolina L., Pistacia atlantica Desf, Rheum ribes L., Sarcopoterium spinosum (L.) Spach and Teucrium polium L. have traditionally been used as herbal antidiabetic medicines. However their alleged benefits and mechanisms remain elusive.

Aim of the study

This study aimed to evaluate the effect of water extracts of these plants in in vitro and in vivo experiments.

Materials and methods

In vitro enzymatic starch digestion with aqueous extracts from plants at concentrations of 1, 5, 10, 12.5, 25, 50 and 100 mg/ml was assayed using α-amylase and α-amyloglucosidase. Acarbose was used as control and glucose liberation was determined by glucose oxidase method. Oral starch tolerance test (OSTT) and oral glucose tolerance test (OGTT) were determined for the plant extracts at concentrations 125, 250 and 500 mg/kg b.wt. on Sprague-Dawley rats. Blood glucose levels in rats treated with plant extracts and drugs (acarbose or metformin and glipizide) were measured at −30, 0, 45, 90 and 135 min.

Results

Compared to acarbose (IC50 = 1.2 μg/ml), water extracts of Pistacia atlantica, Rheum ribes and Sarcopoterium spinosum exerted significant dose dependent dual inhibition of α-amylase and α-glucosidase in in vitro enzymatic starch digestion bioassay, with IC50s; 46.98, 58.9 and 49.9 mg/ml, respectively. Comparable in vivo results were obtained for starch-fed rats, exhibiting significant acute postprandial antihyperglycemic efficacies. While Achillea santolina and Teucrium polium extracts lacked any favourable in vitro anti-α-amylase and anti-α-glucosidase effect, other modes of action can possibly explain their substantial acute antihyperglycemic activities in starch-treated rats. Except for Pistacia atlantica extracts, none of the investigated extracts qualified for improving the glucose intolerance in fasted rats on glucose loading.

Conclusions

Pistacia atlantica, Rheum ribes and Sarcopoterium spinosum can be considered as potential candidates for amelioration/management of type 2 diabetes.  相似文献   
128.
129.

Background

Nck1 and Nck2 adaptor proteins are involved in signaling pathways mediating proliferation, cytoskeleton organization and integrated stress response. Overexpression of Nck1 in fibroblasts has been shown to be oncogenic. Through the years this concept has been challenged and the consensus is now that overexpression of either Nck cooperates with strong oncogenes to transform cells. Therefore, variations in Nck expression levels in transformed cells could endorse cancer progression.

Methods

Expression of Nck1 and Nck2 proteins in various cancer cell lines at different stages of progression were analyzed by western blots. We created human primary melanoma cell lines overexpressing GFP-Nck2 and investigated their ability to proliferate along with metastatic characteristics such as migration and invasion. By western blot analysis, we compared levels of proteins phosphorylated on tyrosine as well as cadherins and integrins in human melanoma cells overexpressing or not Nck2. Finally, in mice we assessed tumor growth rate of human melanoma cells expressing increasing levels of Nck2.

Results

We found that expression of Nck2 is consistently increased in various metastatic cancer cell lines compared with primary counterparts. Particularly, we observed significant higher levels of Nck2 protein and mRNA, as opposed to no change in Nck1, in human metastatic melanoma cell lines compared with non-metastatic melanoma and normal melanocytes. We demonstrated the involvement of Nck2 in proliferation, migration and invasion in human melanoma cells. Moreover, we discovered that Nck2 overexpression in human primary melanoma cells correlates with higher levels of proteins phosphorylated on tyrosine residues, assembly of Nck2-dependent pY-proteins-containing molecular complexes and downregulation of cadherins and integrins. Importantly, we uncovered that injection of Nck2-overexpressing human primary melanoma cells into mice increases melanoma-derived tumor growth rate.

Conclusions

Collectively, our data indicate that Nck2 effectively influences human melanoma phenotype progression. At the molecular level, we propose that Nck2 in human primary melanoma promotes the formation of molecular complexes regulating proliferation and actin cytoskeleton dynamics by modulating kinases or phosphatases activities that results in increased levels of proteins phosphorylated on tyrosine residues. This study provides new insights regarding cancer progression that could impact on the therapeutic strategies targeting cancer.  相似文献   
130.
Primary pericardial sarcomas are extremely rare. We report a case of 19 year old male who presented with cough, dyspnoea, and orthopnea. Investigations and exploratory thoracotomy revealed a large pericardial mass. Surgical debulking of the tumor was performed and the histopathological examination was compatible with synovial sarcoma. The tumor was unresectable due to its invasion and adhesion to mediastinal structures. Hence patient was started on palliative chemotherapy (adriamycin and ifosfamide based). ...  相似文献   
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