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91.
92.
巨噬细胞迁移抑制因子最初是由于能抑制体外巨噬细胞随机迁移而被发现,现在它作为一种重要的调节因子参与一系列炎症性疾病过程.我们最近发现,巨噬细胞迁移抑制因子的缺失使一些由炎症介质诱发的白细胞-内皮细胞相互作用减弱,提示巨噬细胞迁移抑制因子在炎症反应中起作用的机制之一是促进白细胞聚集.…… 相似文献
93.
Risk of second primary malignancy in patients with sinonasal tumors: a population‐based cohort study 下载免费PDF全文
Ashwin Ganti BA Max A. Plitt MD Edward C. Kuan MD MBA Hannah N. Kuhar BS Pete S. Batra MD FACS Bobby A. Tajudeen MD 《International forum of allergy & rhinology》2018,8(6):756-762
Background
The 5‐year overall survival rate for patients with sinonasal cancers has remained around 50% for the last 3 decades. Prior studies on head and neck cancers have suggested that 1 reason for poor survival is the frequent development of second primary malignancies (SPMs). The purpose of this study is to assess overall and site‐specific risks of SPM following treatment of sinonasal malignancy.Methods
A retrospective, population‐based cohort study was performed on 2614 patients in the Surveillance, Epidemiology, and End Results (SEER) database who were diagnosed with primary sinonasal malignancy between 1973 and 2014. Standardized incidence ratios (SIRs) and absolute excess risks (AERs) were calculated to assess risk of SPM relative to incidence in the general population.Results
A total of 422 (16.1%) patients with primary sinonasal malignancies developed a total of 480 SPMs. This cohort had a significantly higher frequency of SPMs than expected in the general population (SIR 1.32; 95% confidence interval [CI], 1.20 to 1.44; AER 53.41). Site‐specific analyses of SIRs suggested highest risk of malignancy in the sinonasal tract (SIR 75.64; 95% CI, 53.53 to 103.83; AER 17.22), followed by bone, eye and orbit, oral cavity and pharynx, and lung and mediastinum.Conclusion
Patients with history of sinonasal cancer are at significantly increased risk of developing an SPM. Careful monitoring for development of additional tumors may be warranted.94.
The lamina push test: an alternative to the globe push test for identifying the medial orbit during endoscopic sinus surgery 下载免费PDF全文
Ravi R. Shah MD William W. Thomas MD Edward C. Kuan MD MBA David W. Kennedy MD 《International forum of allergy & rhinology》2018,8(9):1073-1075
Background
Aside from endoscopic and image guidance confirmation, the standard method of identifying the lamina involves the surgeon or an assistant applying gentle pressure on the globe externally. This globe push test requires the surgeon to remove one instrument from the endoscopic field or an assistant to press on the globe, and the test is most useful when either the periorbita or periorbital fat is exposed. We propose an alternative, equally accurate, and more efficient technique dubbed the lamina push test.Methods
A blunt instrument is used to gently apply lateral pressure in the expected location of the medial orbital wall. If the lamina has been adequately skeletonized, the entire lamina will be seen to move as a unit. If residual ethmoid partitions are present, no movement or only localized movement is observed.Results
Using the lamina push test, we have been able to safely identify the lamina papyracea in all patients undergoing endoscopic sinus surgery, without injury to the lamina or orbital contents. The use of direct pressure significantly increases the movement of an intact lamina.Conclusion
The lamina push test is a safe and effective technique for identification of the medial orbital wall, confirmation of removal of all lateral ethmoid partitions, and verification of lamina integrity. It enables more consistent identification of an intact lamina, allows the surgeon to keep both instruments in the endonasal surgical field, and does not require an assistant.95.
Bo Huang Enayet Talukder Lixin Han Pei-Fen Kuan 《Journal of biopharmaceutical statistics》2019,29(1):189-202
One of the most critical decision points in clinical development is Go/No-Go decision-making after a proof-of-concept study. Traditional decision-making relies on a formal hypothesis testing with control of type I and type II error rates, which is limited by assessing the strength of efficacy evidence in a small isolated trial. In this article, we propose a quantitative Bayesian/frequentist decision framework for Go/No-Go criteria and sample size evaluation in Phase II randomized studies with a time-to-event endpoint. By taking the uncertainty of treatment effect into consideration, we propose an integrated quantitative approach for a program when both the Phase II and Phase III trials share a common endpoint while allowing a discount of the observed Phase II data. Our results confirm the argument that an increase in the sample size of a Phase II trial will result in greater increase in the probability of success of a Phase III trial than increasing the Phase III trial sample size by equal amount. We illustrate the steps in quantitative decision-making with a real example of a randomized Phase II study in metastatic pancreatic cancer. 相似文献
96.
Yen‐Tze Liu Ming‐Ju Hsieh Jen‐Tsun Lin Gene Chen Chia‐Chieh Lin Yu‐Sheng Lo Yi‐Ching Chuang Yi‐Ting Hsi Mu‐Kuan Chen Ming‐Chih Chou 《Environmental toxicology》2019,34(4):513-520
The incidence of oral cancer is increasing all over the world, with rates particularly high in Southeast Asian countries, such as Taiwan. Coronarin D (CD) has been confirmed to have anti‐inflammatory, anti‐bacterial effects, and anti‐apoptotic effects in human hepatocellular carcinoma and nasopharyngeal carcinoma. The purpose of this study is to explore whether CD has a suppression effect on oral cancer cells and the mechanisms involved. The results of our study revealed the significantly decreased cancer cell viability and increased activation of apoptosis via increased loss of mitochondrial membrane potential, increased death receptors, leading to the activation of caspase‐8, ‐9, ‐3. Moreover, the rate of apoptosis of cells treated with CD plus JNK inhibitors was decreased compared to CD‐treated cells. This is the first study to demonstrate that CD induces apoptosis in human oral cancer cells and can be expected to be a promising anticancer agent for oral cancer treatment. 相似文献
97.
Yen‐Yu Chen Yuh‐Ming Chang Kuan‐Yi Wang Pei‐Ni Chen You‐Cheng Hseu Ke‐Min Chen Kun‐Tu Yeh Chih‐Jung Chen Li‐Sung Hsu 《Environmental toxicology》2019,34(3):233-239
Glioblastoma (GBM) is the most mortality brain cancer in the world. Due to high invasion and drug resistance cause the poor prognosis of GBM. Naringenin, an ingredient of citrus, exhibits many cellular functions such as antioxidant, anti‐inflammation, and anticancer. Naringenin inhibits the migration of bladder and lung cancer via modulation of MMP‐2 and/or MMP‐9 activities, Naringenin inhibits migration and trigger apoptosis in gastric cancer cells through downregulation of AKT pathway. However, the effects of naringenin in GBM still remain to be elucidated. In this study, we reveal the molecular mechanisms of naringenin in the inhibition of migration and invasion in GBM. No overt alternation of cell proliferation was found in of GBM 8901 cells treated with different concentration of naringenin. Slight decreased cell viability was found in GBM 8401 cell treated with 200 and 300 μM naringenin. Significant reduction of migration and invasion as assayed by Boyden chamber analysis was found in of GBM cells treated with 100, 200, and 300 μM naringenin. Zymography analysis also revealed that the activities of MMP‐2 and MMP‐9 of GBM cells were significantly inhibited in response to 100, 200, or 300 μM naringenin treatment. Proteins of MMP‐2 and MMP‐9 were downregulated in naringenin treated GBM cells. In addition, naringenin also attenuated the activities of ERK and p38. Naringenin decreased mesenchymal markers (snail and slug) expression as revealed by Western blot analysis. Taken together, our findings indicated that naringenin eliminated the migration and invasion of GBM cells through multiple mechanisms including inhibition of MMPs, ERK, and p38 activities and modulation of EMT markers. Our results also suggested that naringenin may be a potential agent to prevent metastasis of GBM. 相似文献
98.
Chia‐Ming Yeh Ming‐Ju Hsieh Jia‐Sin Yang Shun‐Fa Yang Yi‐Ting Chuang Shih‐Chi Su Meng‐Yuan Liang Mu‐Kuan Chen Chiao‐Wen Lin 《Environmental toxicology》2019,34(10):1085-1093
Geraniin has been reported to have numerous biological activities, including antiviral, antihypertensive, antihyperglycaemic, liver protective, antidiabetic, and apoptotic activities. However, the anti‐migration effects of geraniin on oral cancer remain elusive. In this study, we revealed the potential antitumor mechanisms of geraniin through the inhibition of the migration and invasion of human oral cancer cell lines SCC‐9 and SCC‐14. The results of gelatin zymography and Western blot assays revealed that geraniin significantly reduced the activity and expression of matrix metalloproteinase‐2 (MMP‐2) of oral cancer cells in a concentration‐dependent manner. Furthermore, geraniin potently suppressed the phosphorylation of focal adhesion kinase (FAK), Src, and extracellular signal‐regulated kinase (ERK)1/2 but did not affect the phosphorylation of p38 mitogen‐activated protein kinase (MAPK) and c‐Jun N‐terminal kinase 1/2. Moreover, blocking the MAPK/ERK1/2 pathway significantly enhanced the anti‐migration ability of geraniin in oral cancer cells. In conclusion, we demonstrated that geraniin inhibits the motility of SCC‐9 and SCC‐14 cells in vitro through a molecular mechanism that involves the attenuation of MMP‐2 expression and activity mediated by decreased FAK/Src and ERK1/2 pathways. 相似文献
99.
Kuan Rong Chan Eugenia Z. Ong Hwee Cheng Tan Summer Li-Xin Zhang Qian Zhang Kin Fai Tang Nivashini Kaliaperumal Angeline Pei Chiew Lim Martin L. Hibberd Soh Ha Chan John E. Connolly Manoj N. Krishnan Shee Mei Lok Brendon J. Hanson Chao-Nan Lin Eng Eong Ooi 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(7):2722-2727
Viruses must evade the host innate defenses for replication and dengue is no exception. During secondary infection with a heterologous dengue virus (DENV) serotype, DENV is opsonized with sub- or nonneutralizing antibodies that enhance infection of monocytes, macrophages, and dendritic cells via the Fc-gamma receptor (FcγR), a process termed antibody-dependent enhancement of DENV infection. However, this enhancement of DENV infection is curious as cross-linking of activating FcγRs signals an early antiviral response by inducing the type-I IFN-stimulated genes (ISGs). Entry through activating FcγR would thus place DENV in an intracellular environment unfavorable for enhanced replication. Here we demonstrate that, to escape this antiviral response, antibody-opsonized DENV coligates leukocyte Ig-like receptor-B1 (LILRB1) to inhibit FcγR signaling for ISG expression. This immunoreceptor tyrosine-based inhibition motif-bearing receptor recruits Src homology phosphatase-1 to dephosphorylate spleen tyrosine kinase (Syk). As Syk is a key intermediate of FcγR signaling, LILRB1 coligation resulted in reduced ISG expression for enhanced DENV replication. Our findings suggest a unique mechanism for DENV to evade an early antiviral response for enhanced infection.Despite long-lived serotype-specific immunity upon initial infection, predicted global prevalence of dengue now surpasses World Health Organization estimates by more than threefold with 390 million cases annually (1). Furthermore, the risk of severe disease is augmented by cross-reactive or subneutralizing levels of antibody (2, 3), which opsonize dengue virus (DENV) to ligate Fc-gamma receptor (FcγR) for entry into monocytes, macrophages, and dendritic cells, a phenomenon known as antibody-dependent enhancement (ADE) of DENV infection (4, 5). The resultant greater viral burden leads to increased systemic inflammation that precipitates plasma leakage, a hallmark of dengue hemorrhagic fever (6). However, ligation of the activating FcγRs by immune complexes has been shown to induce type-I IFN stimulated genes (ISGs), independent of autocrine or paracrine IFN activity, unless the inhibitory FcγRIIB is coligated (7). We and others reported recently that coligation of FcγRIIB by DENV immune complexes requires high antibody concentration, and such coligation inhibited the entry of DENV immune complexes into monocytes (8, 9). At low antibody concentrations where ADE occurs, the inhibitory FcγRIIB is not coligated (9). Ligation of the activating FcγRs by DENV opsonized with subneutralizing levels of antibody would thus induce the expression of ISGs and hinder DENV replication (10). Here, we demonstrate that DENV employs a unique evasive mechanism by coligating LILRB1 to down-regulate the early antiviral responses triggered by activating FcγRs for ADE. 相似文献