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41.
健脾化瘀中药提高胞嘧啶脱氨酶/单纯疱疹病毒胸苷激酶基因治疗肝细胞癌的实验研究 总被引:2,自引:0,他引:2
目的:观察健脾化瘀中药提高胞嘧啶脱氨酶/单纯疱疹病毒胸苷激酶基因治疗肝细胞癌的作用。方法:脂质体lipofectamine将含有双自杀基因的腺病毒载体pAd-CD/TK导人293细胞,收集病毒上清转染人肝癌细胞BEL7402,MTT法测定BEL7402细胞存活率。裸鼠人肝癌模型转染CD/TK双自杀基因后,给予5-FC500mg/kg,GCV 100mg/kg腹腔注射,同时予健脾化瘀中药960复方灌胃。观察肿瘤生长情况。结果:给予前体药物5-FC和GCV后,CD/TK转染细胞被杀死。并表现出较强的旁观者效应。转染细胞比例达到10%即表现出较强的杀伤作用(P<0.01)。健脾化瘀中药960复方具有提高旁观者效应作用,1.67ml/kg和2.5ml/kg960复方含药血清组细胞存活率显著低于对照组(P<0.01)。转染基因组应用5-FC和GCV治疗后,裸鼠肝癌的生长明显受到抑制(P<0.05),抑瘤率39.42%,单用中药组抑瘤率18.04%,中药与CD/TK 5-FC/GCV联合运用组,较单纯CD/5-FC/HSV-tk/GCV对裸鼠肿瘤模型的生长抑制作用更加明显(P<0.05),抑瘤率55.10%。结伦:腺病毒介导CD/TK自杀基因可有效地杀死人肝癌BEL7402细胞,健脾化瘀中药960复方具有显著提高CD/TK双自杀基因对人肝癌细胞的抑杀作用。 相似文献
42.
Gene therapy is considered a feasible approach for the treatment and prevention of HIV/AIDS. Targeting both viral genes and host dependency factors can interfere with the viral lifecycle and prevent viral replication. A number of approaches have been taken to target these genes, including ribozymes, aptamers, and RNAi based therapies. A number of these therapies are now beginning to make their way into clinical trials and providing proof of principle that gene therapy is a safe and realistic option for treating HIV. Here, we focus on those therapies that have progressed along the pipeline to preclinical and clinical testing. 相似文献
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Nervous system tumors are one of the leading causes of cancer related death. Specific mechanisms facilitating the invasive
behavior of gliomas remain obscure. Advanced simulation models of the in vivo response to therapy conditions should potentially
improve malignant glioma treatment. Expressional profiling of vimentin––one of reliable pro-invasive tumor makers––in those
simulation models was the goal of this study, in order to estimate a pro-invasive response of surviving malignant glioma cells
under clinically relevant therapeutic conditions. Human U87-MG malignant glioma cells were used. These cells are characterized
by the wild p53-phenotype, which is relevant for the majority of primary malignant glioblastomas. Experimental design foresaw the cells to
undergo either irradiation or chemo-treatment with temozolomide alone, or combined treatment. Expression profiling of vimentin
was performed by quantitative “Real-Time”-PCR under all treatment conditions simulating diverse tumor regions. Here we demonstrated
that vimentin expression patterns in human malignant glioma cells strongly depend on cellular density, algorithms of drug
delivery and chemo/radio treatment. Substantial differences were recognized between immediate and late therapy effects. Significant
increase in vimentin expression levels was detected particularly in low-density cell cultures under durable treatment with
constant concentration levels of temezolomide. Simulation of variable intratumoral regional conditions (central intratumoral
regions vs. disseminated malignant cells in peripheral regions) demonstrated differential response of vimentin expression
in malignant glioma cell cultures treated under clinically relevant conditions. Slight ebbing of expression levels as late
effects of the treatment in confluent cultures may correspond to necrotic processes clinically observed in central intratumoral
regions. Contrary, in disseminated malignant cells of peripheral regions therapy resulted in vimentin-inducing effects. This
is in agreement with the clinical observations of an increased aggressiveness and malignancy grade of post-operatively chemo/radio-treated
malignant gliomas. 相似文献
48.
Jesús Vaquero Mercedes Zurita Miguel A. Rico Concepcion Aguayo Celia Bonilla Esperanza Marin Noemi Tapiador Marta Sevilla David Vazquez Joaquin Carballido Cecilia Fernandez Gregorio Rodriguez-Boto Mercedes Ovejero 《Cytotherapy》2018,20(6):806-819
Background aims
Cell therapy with autologous mesenchymal stromal cells (MSCs) in patients with spinal cord injury (SCI) is beginning, and the search for its better clinical application is an urgent need.Methods
We present a phase 2 clinical trial in patients with chronic SCI who received three intrathecal administrations of 100 x 106 MSCs and were followed for 10 months from the first administration. Efficacy analysis was performed on nine patients, and safety analysis was performed on 11 patients. Clinical scales, urodynamic, neurophysiological and neuroimaging studies were performed previous to treatment and at the end of the follow-up.Results
The treatment was well-tolerated, without any adverse event related to MSC administration. Patients showed variable clinical improvement in sensitivity, motor power, spasms, spasticity, neuropathic pain, sexual function or sphincter dysfunction, regardless of the level or degree of injury, age or time elapsed from the SCI. In the course of follow-up three patients, initially classified as ASIA A, B and C, changed to ASIA B, C and D, respectively. In urodynamic studies, at the end of follow-up, 66.6% of the patients showed decrease in postmicturition residue and improvement in bladder compliance. At this time, neurophysiological studies showed that 55.5% of patients improved in somatosensory or motor-evoked potentials, and that 44.4% of patients improved in voluntary muscle contraction together with infralesional active muscle reinnervation.Conclusions
The present guideline for cell therapy is safe and shows efficacy in patients with SCI, mainly in recovery of sphincter dysfunction, neuropathic pain and sensitivity. 相似文献49.
50.
Promoter optimisation of lentiviral vectors for efficient insulin gene expression in canine mesenchymal stromal cells: potential surrogate beta cells 下载免费PDF全文