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131.
Small intestinal organoid-derived SP cells contribute to repair of irradiation-induced skin injury 总被引:3,自引:0,他引:3
He DN Qin H Liao L Li N Zhu WM Yu BJ Wu X Zhao RC Li JS 《Stem cells and development》2005,14(3):285-291
Side population (SP) cells, characterized by their ability to efflux the fluorescent dye Hoechst 33342, were isolated from the small intestine of mice. In the abdominal irradiation model, small intestinal organoid-derived SP (sioSP) cells from ROSA 26 mice were submucosally injected into the small intestinal of the irradiated C57BL/6 mice. In contrast to the control mice, mice receiving sioSP cell transplantation demonstrated far less skin injury. Most importantly, hairs in the irradiated body part of the transplanted mice almost remained black, whereas the counterpart in the control mice almost turned white. Histochemistry studies showed the donor cells gave rise to skin cells in the irradiated skin. Thus, our study demonstrated for the first time that stem cells from the small intestine can differentiate into skin cells under local cues and thus supports the theory of stem cell plasticity. 相似文献
132.
Immunohistochemical and molecular assessment of human herpesvirus type 8 in gastrointestinal tumours
BACKGROUND: Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the gastrointestinal tract, histologically identified as highly cellular spindle or epithelioid cell tumours, and often positive for CD34 (60-70%). Kaposi's sarcomas (KSs) are similar to GISTs: they are most often found in the gastrointestinal tract (although cutaneous lesions do occur), they are also composed of spindle or epithelioid cells (although erythrocytes are also seen), and the tumour cells are nearly all positive for CD34. Human herpesvirus type 8 (HHV-8) DNA has been found consistently in all types of KS, in particular in CD34 positive KS tumour cells. However, the association between HHV-8 and GIST has not been investigated. AIMS: To assess the presence of HHV-8 in GISTs. METHODS: Paraffin wax embedded tissues of 86 primary GISTs and their recurrent or metastatic tumours were analysed immunohistochemically for the CD34 antigen and HHV-8 latent nuclear antigen 1 (LNA-1) and by means of the nested polymerase chain reaction (PCR) and real time PCR for HHV-8 DNA. RESULTS: None of the 86 GISTs contained HHV-8 DNA sequences or LNA-1 positive cells. CONCLUSIONS: These results demonstrate the lack of HHV-8 infection in GIST tumour cells. HHV-8 does not appear to play a role in the pathogenesis of GIST, irrespective of the status of the tumour. 相似文献
133.
采用含造影剂及显色剂的填充剂对成年SD大鼠动脉血管系统进行灌注,并借助数字X射线成像设备对灌注效果进行实时监测,通过断层解剖成像系统获取切削间距为100 μm的二维断面解剖数据集(图像分辨率为4917×3446×24 bit,共1 464张),最后利用Visual C 结合可视化工具包编程实现数据集的动脉分割及三维可视化,得到数字化SD大鼠动脉血管系统的三维模型.该模型能提供大鼠动脉血管系统的空间结构信息,为实验大鼠血管系统的研究提供了更为准确可靠的形态学参考. 相似文献
134.
Different applications of polymerases with and without proofreading activity in single-nucleotide polymorphism analysis 总被引:2,自引:0,他引:2
Zhang J Li K Liao D Pardinas JR Chen L Zhang X 《Laboratory investigation; a journal of technical methods and pathology》2003,83(8):1147-1154
With the completion of the human genome project, single-nucleotide polymorphisms (SNPs) have become the focus of intense study in biomedical research. Polymerase-mediated primer extension has been employed in a variety of SNP assays. However, these SNP assays using polymerase without proofreading function are compromised by their low reliability. Using a newly developed short amplicon harboring restriction enzyme site, EcoR-I, we were able to compare the single-base discrimination abilities of polymerases with and without proofreading function in primer extension in a broad range of annealing temperatures. Thermodynamic analysis demonstrated a striking single-nucleotide discrimination ability of polymerases with proofreading function. Using unmodified 3'-end allele-specific primers, only template-dependent products were generated by polymerase with proofreading activity. This powerful single-base discrimination ability of exo(+) polymerases was further evaluated in primer extension using three types of 3' terminally modified allele-specific primers. As compared with the poor fidelity in primer extension of polymerases lacking 3' exonuclease activity, this study provides convincing evidence that the use of proofreading polymerases in combination with 3'-end modified allele-specific primers can be a powerful new strategy for the development of SNP assays. 相似文献
135.
Ren-Wu Chen X.-C. May Lu Changping Yao Zhilin Liao Zhi-Gang Jiang Hans Wei Hossein A. Ghanbari Frank C. Tortella Jitendra R. Dave 《Neuroscience letters》2007
In an earlier study, we demonstrated that PAN-811 (3-aminopyridine-2-carboxaldehyde thiosemicarbazone), a novel neuroprotectant, provides protection against glutamate, staurosporine, veratridine, or hypoxia/hypoglycemia toxicities in primary cortical neuronal cultures by upregulating Bcl-2 expression [R.-W. Chen, C. Yao, X.C. Lu, Z.-G. Jiang, R. Whipple, Z. Liao, H.A. Ghanbari, B. Almassian, F.C. Tortella, J.R. Dave. PAN-811 (3-aminopyridine-2-carboxaldehyde thiosemicarbazone), a novel neuroprotectant, elicits its function in primary neuronal cultures by upregulating Bcl-2 expression. Neuroscience 135 (2005) 191–201]. Both JNK (c-Jun N-terminal kinase) and p38 MAP (mitogen-activated protein) kinase activation have a direct inhibitory action on Bcl-2 by phosphorylation. In the present study, we continued to explore the mechanism of PAN-811 neuroprotection. Our results indicate that treatment of cultured cortical neurons with glutamate (100 μM) induces phosphorylation of both JNK and p38 MAPK. Specifically, pretreatment of neurons with 10 μM PAN-811 (an optimal neuroprotective concentration) for 1 h, 4 h, or 24 h significantly suppresses glutamate-mediated activation of both JNK and p38 MAPK. Furthermore, the p38 MAPK-specific inhibitor SB203580 and the JNK-specific inhibitor SP600125 prevented glutamate-induced neuronal death in these primary cultures. Our results demonstrate that glutamate-induced phosphorylation of JNK and p38 MAPK is suppressed by PAN-811, which might contribute to Bcl-2 upregulation and PAN-811 neuroprotection. 相似文献
136.
Autoimmunity in the pathogenesis of cardiomyopathy 总被引:3,自引:0,他引:3
137.
H.-H. Wang L.-N. Liao C.-L. Lin L.-L. Yen Y.-M. Hsiao J.-L. Ko 《Transfusion Clinique et Biologique》2021,28(1):44-50
BackgroundPlatelet transfusion is required to treat haemo-oncology or trauma patients. Platelet apheresis (PA) performed with apheresis equipment has increased rapidly in recent years. Leucocyte-reduced platelet apheresis (LRPA) can reduce the risk of platelet refractoriness and febrile nonhemolytic transfusion reactions (FNHTRs) for transfusion. Accordingly, this study aimed to investigate and compare the platelet metabolic and functional responses between PA performed with Haemonetics and LRPA performed with Trima Accel cell separator.MethodsThe qualities of platelets collected through PA and LRPA were evaluated in terms of visual appearance, morphology, platelet-aggregation changes, metabolic activities, and bacterium-screening test during 5-day storage. Statistical analyses included two-sample t-test and generalised estimating equation(GEE) method.ResultsDuring 5-day storage in LRPA, residual leucocytes were all <1.0×106, and the parameters of platelet function were as follows: platelet aggregated to agonists such as adenosine 5′-diphosphate (ADP) and collagen, and the extent of shape change and pO2 showed no statistically significant difference between PA and LRPA. The hypotonic shock reaction (HSR) on days 0, 1, and 3 were significantly higher in LRPA than in PA (71.78±6.92 vs. 64.10±7.42; P=0.002; 71.53±8.98 vs. 62.96±9.84; P=0.007; 68.05±7.28 vs. 57.76±6.80; P<0.0001, respectively). Values of mean platelet volume (MPV) were statistically larger in PA than in LRPA on days 0, 1, and 3. On day 5, the swirling score was higher in LRPA than in PA. The mean lactate levels had no statistically significant difference between PA and LRPA. Moreover, no growth was observed through bacterium-screening test conducted on 40 samples.ConclusionComparison of LRPA and PA products collected from the Trima Accel and Haemonetics automated blood-collection systems, respectively, revealed that both products possessed good platelet qualities even though additional processes are needed to reduce leucocytes. Furthermore, investigating the outcomes of other apheresis instruments with focus on the safety of donors, products, and recipients is necessary. 相似文献
138.
目的探讨导致产妇发生产褥期乳腺炎(PM)的影响因素。 方法选择2020年9月1日至12月31日,在成都市某三甲妇女儿童医院分娩,并进行产后42 d随访的1 162例产妇为研究对象。根据产妇产后42 d内是否发生PM,将其分为PM组(n=103)与对照组(n=1 059)。采用本研究自行设计的《产褥期乳腺炎相关影响因素调查问卷》(以下简称为《调查问卷》),联合《中国简式心理状态剖面图(POMS)量表》(以下简称为《POMS量表》),分别对2组产妇进行调查。《调查问卷》内容主要包括产妇一般人口学资料、妊娠及疾病、药物使用、母乳喂养、饮食及生活习惯等10个维度,共计50个条目。《POMS量表》包括心理焦虑等7个维度,共计40个条目。对2组产妇《调查问卷》条目及《POMS量表》评分,采用独立样本t检验、χ2检验及Fisher确切概率法等进行统计学比较。本研究遵循的程序符合病例收集医院医学伦理委员会要求,经过该伦理委员会批准[审批文号:科研伦审2021(29)],并与研究对象签署临床研究知情同意书。2组产妇的年龄等一般临床资料比较,差异无统计学意义(P>0.05)。 结果①本研究纳入产妇的PM发生率为8.9%(103/1 162),产后第3、4周PM发生率最高,分别为2.7%(31/1 162)与2.4%(28/1 162)。②本研究2组产妇围生期补充铁剂及口服益生菌占比,乳头皲裂程度、吸奶器使用时间及频率、乳头保护罩与乳头保护霜使用频率构成比,哺乳衔接姿势正确率,哺乳时乳房疼痛程度、哺乳内衣穿戴率等分别比较,差异均有统计学意义(P<0.05)。③PM组产妇《POMS量表》焦虑评分为(7.1±5.0)分,显著高于对照组的(5.3±4.1)分,并且差异有统计学意义(t=-3.540、P=0.001)。④将上述影响产妇发生PM的单因素分析中差异有统计学意义因素,并结合已有研究结果与临床经验,纳入10项影响因素,进行多因素非条件logistic回归分析结果显示,产妇围生期补充铁剂(OR=3.351,95%CI:1.949~5.758,P<0.001),乳头皲裂(OR=3.564,95%CI:1.909~6.654,P<0.001),吸奶器使用频率>1次/d(OR=5.102,95%CI:1.047~24.876,P=0.044),乳头保护霜使用频率>1次/d(OR=2.147,95%CI:1.156~3.987,P=0.016),哺乳衔接姿势不正确(OR=2.311,95%CI:1.202~4.445,P=0.012),穿戴不舒适哺乳内衣(OR=2.322,95%CI:1.008~5.347,P=0.048),不穿戴哺乳内衣(OR=3.516,95%CI:1.821~6.789,P<0.001),焦虑评分高(OR=1.073,95%CI:1.007~1.143,P=0.029),均为导致产妇发生PM的独立危险因素;而围生期口服益生菌(OR=0.110,95%CI:0.025~0.478,P=0.003)是其独立保护因素。 结论通过制定临床干预措施,指导产褥期产妇纠正不正确行为,如围生期补充铁剂、吸奶器与乳头保护霜使用不当,哺乳内衣穿戴及哺乳行为不规范等,提倡产妇围生期口服益生菌,缓解产妇焦虑情绪,对预防产妇PM发生具有重要意义。 相似文献
139.
140.
目的探讨先天性生殖器官异常孕妇的围生结局。方法选择2009年1月至2019年12月,于四川大学华西第二医院活产分娩的99779例单胎妊娠孕妇为研究对象。根据是否合并先天性生殖器官异常,将其分为观察组(n=324,合并)及对照组(n=99455,未合并)。回顾性分析2组孕妇的临床病例资料,总结观察组不同类型先天性生殖器官异常孕妇的围生结局特点。采用χ^(2)检验及独立样本t检验,对2组孕妇妊娠期各并发症发生率、剖宫产率及新生儿出生体重等,进行统计学分析。本研究遵循的程序符合2013年修订的《世界医学协会赫尔辛基宣言》要求。结果①观察组孕妇最常见先天性生殖器官异常前3位依次为纵隔子宫、单角/残角子宫及弓形子宫,分别占35.2%(114/324)、26.2%(85/324)及13.9%(45/324)。包括既往妊娠次数在内,观察组孕妇共计妊娠571次,其中弓形子宫、纵隔子宫孕妇的自然流产率位列前2位,分别为38.5%(35/91)、28.6%(61/213);阴道畸形孕妇足月产率(70.0%),高于子宫畸形者(52.8%),并且差异有统计学意义(χ^(2)=4.432、P=0.035)。②观察组孕妇早产、胎膜早破、胎位异常、胎盘早剥、胎儿生长受限(FGR)、胎盘黏连/植入、子宫破裂及剖宫产率分别为29.6%、29.3%、36.1%、5.9%、2.5%、21.0%、3.4%、78.7%,均分别高于对照组孕妇的9.8%、22.3%、5.7%、1.2%、1.0%、11.5%、1.5%、62.0%;而羊水过少率(0.9%)及新生儿出生体重[(2913±652)g],则显著低于对照组的2.9%、(3254±445)g,并且上述差异均有统计学意义(均为P<0.05)。2组孕妇前置胎盘、妊娠期高血压疾病(HDCP)、产后出血(PPH)及子宫切除率比较,差异均无统计学意义(P>0.05)。结论先天性生殖器官异常孕妇的母、胎围生期并发症发生风险高。提高该病孕妇的孕前及早孕期诊断率,加强围生期保健及处理,可改善其围生结局。 相似文献