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21.
《Vaccine》2022,40(48):6971-6978
Background and aimsRecent studies have reported poor humoral immune response to mRNA vaccines in patients with chronic liver disease (CLD). However, the immunogenicity of ChAdOx1 (vector-based) and BBV152 (inactivated virus) vaccines in patients with CLD and liver transplant recipients (LTRs) is unknown. Therefore, we aimed to assess the immunogenicity of ChAdOx1 and BBV152 vaccines in patients with CLD (including cirrhosis patients) and LTRs.MethodsIn this single-center prospective study, consecutive completely vaccinated (ChAdOx1 or BBV152) non-cirrhosis CLD patients, those with cirrhosis, and LTRs were compared with matched healthy controls for anti-spike antibody and cellular response.ResultsSixty healthy individuals, 50 NCCLD patients, 63 compensated and 50 decompensated cirrhosis, and 17 LTRs were included. The proportion of non-responders was similar among the healthy control (8 %), non-cirrhosis CLD (16 %), and compensated cirrhosis groups (17.5 %;p = 0.3). However, a higher proportion of patients with decompensated cirrhosis (34 %) and LTRs (59 %) were non-responders than the healthy controls (p = 0.001). Cluster of differentiation (CD) 4-effector cells were lower in patients with non-cirrhosis CLD and compensated cirrhosis. CD4-naïve, CD4-effector, B, and B-memory cells were lower in the decompensated cirrhosis group. Although the central memory cells were higher in the decompensated cirrhosis group, they could not differentiate into effector cells. CD4- and CD8-naïve cells were higher in the marrow in the LTRs, while the CD4-effector memory cells and CD4- and CD8-effector cells were lower in the LTRs. Furthermore, B cells were more deficient in the LTRs, suggesting poor antibody response.ConclusionPatients with decompensated cirrhosis and LTRs demonstrated suboptimal humoral and cellular immune responses against recombinant and inactivated COVID-19 vaccines.  相似文献   
22.
The AKT/mTOR signaling pathway is frequently overexpressed in human epithelial ovarian cancer and an attractive target for therapy. In vivo mouse models were confirmative for in vitro findings, where the administration of mTOR inhibitors in ovarian cancer xenografts showed antitumoral as well as antiangiogenic effects. Phase I – II trials are now ongoing with mTOR inhibitors in ovarian cancer patients, some in combination with conventional cytotoxic agents. If further development of mTOR inhibition in ovarian cancer is pursued, studying combinations of mTOR inhibitors with other new targeted therapies would be of interest. mTOR inhibitors in the adjuvant setting could have potential, since, for the moment, there is no standard maintenance therapy in ovarian cancer. A crucial challenge will be to identify strong predictive biomarkers. This review highlights the rationale for the use of mTOR inhibitors in ovarian cancer and summarizes the available preclinical findings.  相似文献   
23.
Tuberous sclerosis complex is an autosomal dominant inherited disorder characterized by generalized involvement and variable manifestations with a birth incidence of 1:6000. In a quarter of a century, significant progress in tuberous sclerosis complex has been made. Two responsible genes, TSC1 and TSC2, which encode hamartin and tuberin, respectively, were discovered in the 1990s, and their functions were elucidated in the 2000s. Hamartin–Tuberin complex is involved in the phosphoinositide 3‐kinase–protein kinase B–mammalian target of rapamycin signal transduction pathway, and suppresses mammalian target of rapamycin complex 1 activity, which is a center for various functions. Constitutive activation of mammalian target of rapamycin complex 1 causes variable manifestations in tuberous sclerosis complex. Recently, genetic tests were launched to diagnose tuberous sclerosis complex, and mammalian target of rapamycin complex 1 inhibitors are being used to treat tuberous sclerosis complex patients. As a result of these advances, new diagnostic criteria have been established and an indispensable new treatment method; that is, “a cross‐sectional medical examination system,” a system to involve many experts for tuberous sclerosis complex diagnosis and treatments, was also created. Simultaneously, the frequency of genetic tests and advances in diagnostic technology have resulted in new views on symptoms. The numbers of tuberous sclerosis complex patients without neural symptoms are increasing, and for these patients, renal manifestations and pulmonary lymphangioleiomyomatosis have become important manifestations. New concepts of tuberous sclerosis complex‐associated neuropsychiatric disorders or perivascular epithelioid cell tumors are being created. The present review contains a summary of recent advances, significant manifestations and therapy in tuberous sclerosis complex.  相似文献   
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Non-myeloablative conditioning has extended the use of allogeneic haematopoietic transplant to many previously ineligible patients. We added the immunosuppressive and antitumour agent sirolimus (rapamycin) to an established transplant regimen of fludarabine 25 mg/m(2) days -7 through -3 and cyclophosphamide 1000 mg/m(2) days -7 and -6, with tacrolimus and methotrexate immunoprophyllaxis. A total of 23 patients with acute myelogenous leukaemia (AML) were treated, with a median age of 59 years (range: 28-72) at transplant. Only seven patients in total were in complete remission prior to transplantation. Nine patients were in chemotherapy-refractory progression and seven were primarily refractory to induction therapy. Six patients received matched sibling, 11 unrelated donor, 1-5/6 matched and five haploidentical (haplo - three of six or four of six matched) transplants. The haplo-recipients also received antithymocyte globulin, all patients engrafted. Only two, both recipients of haploidentical cells, have died from transplant-related causes. Twelve of 23 patients survived at 198-1162-d post-transplant (median 578). Four of 12 survivors relapsed at 83, 88, 243 and 508 d and three were in remission after chemotherapy and donor lymphocyte infusion. Although follow up is short, this data suggests that non-myeloablative haematopoietic cell transplantation with sirolimus (rapamycin)-based immunosuppression may provide disease control over several years in some patients with advanced and poor prognosis AML.  相似文献   
26.
Introduction: Deregulation of the phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) intracellular signaling pathway is common in breast cancer (BC) and has been found to be potentially implicated in resistance to endocrine and anti-HER2 therapies. Targeting the PI3K/Akt/mTOR pathway may remove this inhibition and restore sensitivity to these compounds. Buparlisib (BKM120) is a potent oral pan-class I PI3K inhibitor that is being extensively evaluated in multiple tumor types.

Areas covered: This review briefly summarizes the pharmacodynamics and pharmacokinetics of buparlisib, focusing on preclinical and clinical data in BC and on ongoing randomized trials.

Expert opinion: Overall, buparlisib is a safe and tolerable drug and, despite its peculiar toxicity profile, it is suitable for studies in combination with other anticancer agents in BC. Early-phase clinical trials in BC have provided evidence of antitumor activity. Several trials are being conducted in all the biological subsets of BC, including combinations with endocrine therapy, anti-HER2 agents, PARP-inhibitors and chemotherapy. While clinical results are eagerly awaited, biological material suitable for both genomic and non-genomic analyses is being collected. The authors expect an intense investigation of the potential biomarkers that explain response or resistance to buparlisib and inspire strategies to rationally explore the therapeutic potential of this drug.  相似文献   
27.

Objective

To identify key predictors and survival outcomes of new-onset diabetes after transplant (NODAT) in liver transplant (LT) recipients by using the Scientific Registry of Transplant Recipients.

Patients and Methods

Data of all adult LT recipients between October 1, 1987, and March 31, 2016, were analyzed using various machine learning methods. These data were divided into training (70%) and validation (30%) data sets to robustly determine predictors of NODAT. The long-term survival of patients with NODAT relative to transplant recipients with preexisting diabetes and those without diabetes was assessed.

Results

Increasing age (odds ratio [OR], 1.01; 95% CI, 1.00-1.02; P≤.001), male sex (OR, 1.09; 95% CI, 1.05-1.13; P=.03), and obesity (OR, 1.13; 95% CI, 1.08-1.18; P<.001) were significantly associated with NODAT. Sirolimus as a primary immunosuppressant carried a 33% higher risk of NODAT than did tacrolimus (OR, 1.33; 95% CI, 1.22-1.45; P<.001) at 1 year after LT. Patients with NODAT had significantly decreased 10-year survival than did those without diabetes (63.0% vs 74.9%; P<.001), similar to survival in patients with diabetes before LT (58.9%).

Conclusion

Using a machine learning approach, we found that older, male, and obese recipients are at especially higher risk of NODAT. Donor features do not affect risk. In addition, sirolimus-based immunosuppression is associated with a significantly higher risk of NODAT than other immunosuppressants. Most importantly, NODAT adversely affects long-term survival after LT in a manner similar to preexisting diabetes, indicating the need for more aggressive care and closer follow-up.  相似文献   
28.
哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,m TOR)是衰老和衰老相关疾病的一个关键调节因子。雷帕霉素(rapamycin,RAPA)可通过抑制m TOR通路,诱导和促进细胞自噬的发生。细胞自噬是维持细胞内稳态的主要方式与途径,通过降解多余的、受损的及衰老的蛋白与细胞器,为细胞重建、再生和修复提供必需原料。早老症(hutchinson-gilford progeria syndrome,HGPS)患者细胞中伴随早老蛋白(progerin)的异常聚集;此外,诸如亨廷顿病、帕金森病、阿尔茨海默病等神经退行性疾病细胞内同样出现异常蛋白质的聚集,而这些异常蛋白的清除正依赖于细胞的自噬作用。由此可见,雷帕霉素是潜在的抗衰老、治疗早老症及衰老相关疾病的重要药物。该文主要阐述雷帕霉素促进细胞自噬方面的功能及在HGPS、神经退行性疾病方面的应用。  相似文献   
29.
The splicing factor SF2/ASF is an oncoprotein that is up-regulated in many cancers and can transform immortal rodent fibroblasts when slightly overexpressed. The mTOR signaling pathway is activated in many cancers, and pharmacological blockers of this pathway are in clinical trials as anticancer drugs. We examined the activity of the mTOR pathway in cells transformed by SF2/ASF and found that this splicing factor activates the mTORC1 branch of the pathway, as measured by S6K and eIF4EBP1 phosphorylation. This activation is specific to mTORC1 because no activation of Akt, an mTORC2 substrate, was detected. mTORC1 activation by SF2/ASF bypasses upstream PI3K/Akt signaling and is essential for SF2/ASF-mediated transformation, as inhibition of mTOR by rapamycin blocked transformation by SF2/ASF in vitro and in vivo. Moreover, shRNA-mediated knockdown of mTOR, or of the specific mTORC1 and mTORC2 components Raptor and Rictor, abolished the tumorigenic potential of cells overexpressing SF2/ASF. These results suggest that clinical tumors with SF2/ASF up-regulation could be especially sensitive to mTOR inhibitors.  相似文献   
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