首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   325篇
  免费   16篇
儿科学   3篇
妇产科学   1篇
基础医学   55篇
口腔科学   3篇
临床医学   56篇
内科学   50篇
皮肤病学   16篇
神经病学   30篇
特种医学   6篇
外科学   25篇
预防医学   16篇
眼科学   1篇
药学   31篇
中国医学   7篇
肿瘤学   41篇
  2023年   6篇
  2022年   1篇
  2021年   3篇
  2020年   4篇
  2019年   3篇
  2018年   5篇
  2017年   2篇
  2016年   2篇
  2015年   4篇
  2014年   5篇
  2013年   7篇
  2012年   31篇
  2011年   30篇
  2010年   15篇
  2009年   6篇
  2008年   26篇
  2007年   39篇
  2006年   27篇
  2005年   24篇
  2004年   30篇
  2003年   22篇
  2002年   26篇
  2001年   3篇
  2000年   2篇
  1999年   4篇
  1997年   2篇
  1996年   1篇
  1994年   1篇
  1992年   1篇
  1988年   1篇
  1986年   1篇
  1985年   2篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1979年   1篇
  1965年   1篇
排序方式: 共有341条查询结果,搜索用时 15 毫秒
71.
We report a case of diffuse large B-cell lymphoma occurring in a patient with the hyperimmunoglobulinemia E syndrome, a rare immune disorder defined by elevated immunoglobulin E levels and recurrent bacterial and fungal infections often manifesting as cold abscesses. This case further supports the notion that patients with hyperimmunoglobulinemia E have an increased risk of lymphoid malignancies and should be closely monitored. Despite a theoretic risk of severe infectious complications, chemotherapy was well tolerated and resulted in a sustained complete remission.  相似文献   
72.
We compared the neuroprotective and metabolic effects of chronic treatment with ionotropic or metabotropic glutamate receptor antagonists, in rats bearing a unilateral nigrostriatal lesion induced by 6-hydroxydopamine (6-OHDA). The ionotropic, N-methyl-D-aspartate receptor antagonist MK-801 increased cell survival in the substantia nigra pars compacta (SNc) and corrected the metabolic hyperactivity (increased cytochrome oxidase activity) of the ipsilateral substantia nigra pars reticulata (SNr) associated with the lesion, but showed no effects on the 6-OHDA-induced hyperactivity of the subthalamic nucleus (STN). Significant-although less pronounced-protection of SNc neurons was also observed following treatment with the metabotropic glutamate receptor (mGluR5) antagonist 2-methyl-6-(phenylehtynyl)-pyridine (MPEP). As opposed to MK-801, MPEP abolished the STN metabolic hyperactivity associated with the nigrostriatal lesion, without affecting SNr activity. Specific modulation of STN hyperactivity obtained with mGluR5 blockade may, therefore, open interesting perspectives for the use of this class of compounds in the treatment of Parkinson's disease.  相似文献   
73.
74.
In a wide range of human cancers, increased levels of heat shock protein 27 (Hsp27) are closely associated with tumorigenesis, metastasis, resistance to anticancer therapeutics, and thus poor prognosis. In this study, we evaluate the radiosensitizing effects of Hsp27 gene silencing using OGX-427, a second-generation antisense oligonucleotide (ASO), on the radioresistant head and neck squamous cell carcinoma (HNSCC) SQ20B cells. In vitro, the downregulation of Hsp27 significantly enhanced radiation-induced apoptotic and clonogenic death, and promoted Akt inactivation. In vivo, combining OGX-427 with local tumor irradiation (5 × 2 Gy) led to a significant regression of SQ20B tumors related to a high rate of apoptosis and decreased levels of glutathione antioxidant defenses. Increasing the total radiation dose (15 × 2 Gy) significantly amplified the radiosensitizing effect of OGX-427. Treatment of tumors with OGX-427 plus radiation resulted in a decrease in angiogenesis associated with a reduced activation of the Akt pathway. Furthermore, the combined treatment enhanced the survival of SQ20B-bearing mice and showed no signs of acute and delayed toxicity. Our findings demonstrate for the first time that Hsp27 knockdown enhances the cytotoxic effects of radiotherapy in vivo and provide preclinical proof of principle for clinical trials using Hsp27 antisense technology in the treatment of patients with HNSCC radioresistant cancers.  相似文献   
75.
Exogenous treatment with monosialoganglioside GM1 has been described to afford protection against different apoptotic insults. However, the underlying mechanisms remain to be determined. In this study, we focused on the effect of GM1 on the apoptotic cascade induced by benzo[a]pyrene (B[a]P) in rat hepatic F258 epithelial cells. We first demonstrated that a co-treatment with GM1 (80 microM) reduced B[a]P (50 nM)-induced apoptosis as evidenced by a decrease of both cell population exhibiting nuclear fragmentation and caspase 3 cleavage and activity. We next showed that the p53 phosphorylation and nuclear translocation as well as the intracellular alkalinization related to Na+/H+ exchanger 1 (NHE1) activation, two early events of the apoptosis induced by B[a]P, were not inhibited by GM1. In contrast, the late mitochondria-dependent acidification elicited by B[a]P was inhibited by GM1 co-treatment, and an inhibition of the oxidative stress was also observed. Because GM1 has been shown to reduce the low-molecular weight iron content related to ethanol-induced oxidative stress, we finally investigated the involvement of iron under our conditions. Using the two iron chelators deferiprone and desferrioxamine, we clearly showed that iron played an important role in B[a]P-induced apoptosis in F258 cells, and that B[a]P-treatment resulted in a significant GM1-sensitive increase in (55)Fe uptake. In conclusion, our results indicate that exogenous GM1 partly prevents B[a]P-induced apoptosis by interfering with mitochondria-related intracellular acidification and iron transport.  相似文献   
76.
The known plagionicin A (1) and eight new monotetrahydrofuran acetogenins, plagionicins B-D (2-4) and plagioneurins A-E (5-9), were isolated from the leaves of Disepalum plagioneurum by bioassay-guided purification. The structures of the new compounds were elucidated by spectroscopic methods. The new monotetrahydrofuran (mono-THF) acetogenins exhibited significant in vitro cytotoxicity against the KB cancer cell line, with IC(50) values in the nanomolar range.  相似文献   
77.
An effective virus-like particle (VLP) based prophylactic vaccine designed to protect against persistent infection with human papillomavirus (HPV) types 16 and 18 and subsequent lesion development will need to induce a strong humoral and cellular immune response capable of providing long-term protection. Our objective was to evaluate the ability of an HPV16/18 L1 VLP vaccine formulated with the AS04 adjuvant system (3-O-desacyl-4'-monophosphoryl lipid A (MPL) and aluminium salt) to induce an immune response of higher magnitude and persistence compared to a vaccine formulated with aluminium salt only. We demonstrated that MPL adsorbed onto aluminium salt retains its capacity to activate an innate immune response as assessed by the production of TNFalpha by human monocytes (U937). In addition, vaccination of mice, monkeys or human subjects with AS04 formulations induced higher total anti-L1 VLP16 and L1 VLP18 antibody responses (1.6-8.5-fold) than the aluminium salt only formulations. The enhanced antibody response induced by the AS04 vaccine formulation (1.6-4.1-fold) in monkeys and humans was shown to be targeted to functional neutralising L1 VLP16 and L1 VLP18 epitopes as assessed by V5/J4 specific ELISAs or HPV16 and HPV18 pseudo-neutralization assays. The enhanced immune profile observed with the AS04 formulation in terms of both total, V5/J4 specific and neutralizing antibodies was shown to persist for at least 3.5-year post-vaccination in human subjects. Finally, using the newly developed B cell ELISPOT assay we also demonstrated that the AS04 formulation elicited an increased frequency (2.2-5.2-fold) of HPV L1 VLP specific memory B cells when compared with the aluminium salt only formulations. These data strongly support the role of the AS04 adjuvant, which includes the immunostimulant MPL, in triggering a persistent vaccine-induced immune response of high quality.  相似文献   
78.
Optical Schiff's bases of gossypol were prepared with chiral gossypol and ethylamine. As has been similarly observed among the gossypol enantiomers, the (-)-gossypol ethylimine was more active than either the (+)-gossypol ethylimine or the racemic gossypol ethylimine against KB and MCF7 cells. Gossypolone was also observed to be more toxic than gossypol against both cell lines. All of the gossypol products tested showed comparable toxicity toward MCF7/ADR (adriblastine-resistant) cells. Attempts at producing chiral gossypolone from chiral gossypol failed because of rapid racemization. In addition, the Schiff's base derivatives of gossypolone formed with R-(+)-2-amino-3-phenyl-1-propanol could only be separated at reduced temperature, indicating that gossypolone Schiff's bases are less optical stable than gossypol Schiff's bases.  相似文献   
79.
PURPOSE: To evaluate the feasibility and tolerance of a postoperative course of gemcitabine (GEM) combined with continuous radiation after curative resection of pancreatic adenocarcinoma. METHODS AND MATERIALS: Thirty patients (median age, 61 years; performance status, 0 to 1) with Stage II and III curatively resected pancreatic head adenocarcinoma were included. Gemcitabine 1000 mg/m2 (3 out of 4 weeks, two cycles) was given within 8 weeks of surgery and followed by GEM 300 mg/m2 weekly combined with continuous radiation (45 Gy in 25 fractions, 1.8 Gy per fraction). RESULTS: For GEM alone, all patients received the two courses with dose reductions in 14 of 30 patients (46%). All but 3 patients completed full chemoradiation; 1 stopped radiation because of subocclusion of a gastroenterostomy, and 2 did not start owing to disease progression. Reduction in GEM during radiation was necessary in 12 of 30 patients (40%). No toxic death was noted; World Health Organization Grade 3/4 hematologic and nonhematologic toxicities were seen in 10 of 30 patients (33%) and 3 of 30 patients (10%), respectively. After a median follow-up of 19 months, no late toxicity was reported. Eleven patients died from progressive disease; median disease-free survival and overall survival were 14.5 and 19 months, respectively. CONCLUSION: This adjuvant combination is well tolerated and can be safely administered after curative surgery for pancreatic cancer. Further evaluation of this regimen is ongoing.  相似文献   
80.
In order to assess if oxytocin- and vasopressin-induced mitogenic effects detected on small-cell lung carcinoma (SCLC) cell lines could be transposed on primary SCLC, the aim of the present work was to identify mediators of these mitogenic actions on primary tumours samples. This was addressed on normal human lung tissue, on SCLC and on non-SCLC (NSCLC). Herein, we observe, in normal human lung, that OTR is colocalized with vascular endothelial cells of the lung and is not expressed by lung cells of epithelial nature. We detected mRNA amplification of V1aR, V2R and of a V2R variant. We observed that 86% of SCLC biopsies analyzed expressed at least the OTR and that 71% expressed the OTR, the V1aR and the V2R altogether. Comparatively, 50% of NSCLC biopsies tested expressed at least the OTR and 32% expressed the OTR, the V1aR and the V2R altogether. The occurrence of the V1bR/V3R is of 28 and 18% for SCLC and NSCLC, respectively. Nevertheless, for the SCLC biopsies analyzed in this study, V1bR/V3R expression correlates, in all cases, with the expression of all the other neurohypophysial peptide receptors. Our results suggest that neurohypophysial peptide antagonists may offer promise as a potential new therapeutic modality for the treatment of lung cancer expressing at least one of the neurhypophysial peptide receptor subtypes.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号