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91.
目的:探讨microRNA-100(miR-100)在大鼠肝脏发育成熟和癌变时的表达。方法取新生SD乳鼠、成年SD大鼠肝组织以及经连续喂饲2-乙酰氨基芴加部分肝切除术(2-AAF/PH)诱导的SD大鼠肝癌组织,分别采用实时荧光定量PCR及FISH技术检测miR-100的表达。结果同新生SD乳鼠相比,miR-100在成年SD大鼠肝组织中表达明显升高( P<0.05)。大鼠肝脏癌变组织的miR-100表达较成年大鼠肝组织明显下降( P<0.05),接近于新生SD乳鼠miR-100的表达水平。结论 miR-100可作为SD大鼠肝脏发育成熟的标志,其表达降低可能与肿瘤形成有关。 相似文献
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Ahlem Rafrafi Besma Chahed Safa Kaabachi Wajih Kaabachi Haifa Maalmi Kamel Hamzaoui Fayçal Haj Sassi 《Human immunology》2013
Interleukin 8 (IL-8), is a proinflammatory chemokine, has been reported to have angiogenic activity and to be responsible for tumor-associated angiogenesis in several cancers. In this study, we aimed to study the (IL-8) gene polymorphism in relation with risk development of non small cell lung cancer in Tunisian patient. Two single nucleotide polymorphisms (−251T/A [rs4073], +781C/T [rs2227306]) of the IL-8 gene were screened in 170 patients with NSCLC and 225 healthy controls by PCR–RFLP. 相似文献
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Contaminated recreational waters pose a public health concern, as the potential for waterborne diseases exists in water contaminated with human fecal waste. Worldwide, bacterial indicators such as Escherichia coli, enterococci, and total and fecal coliform are used as indicators of water quality. However, enteric viruses also present a public health concern and their presence cannot always be determined based on bacterial indicators. This study explores the use of molecular detection methods of enteric viruses as indicators of fecal contamination. Four viruses, enterovirus, norovirus genogroups I and II, and male-specific FRNA coliphage, were tested in this study. Highly sensitive RT-PCR methods developed at the University of Hawaii at Manoa were utilized to evaluate environmental samples collected from three lakes in Wuhan, Hubei Province, China. Sixteen of twenty-five sites tested positive for at least one virus. Enterovirus was the most commonly detected virus, followed by norovirus genogroup I. These findings support the use of molecular detection methods to test for enteric virus presence in recreational freshwater sources in China as alternative water quality indicators, and utilize recently developed, highly sensitive methods of detection of these viruses. In addition, these findings suggest that there is substantial fecal contamination of the three lakes tested in this study. 相似文献
97.
Kallol Saha Rushna FirdausSekhar Chakrabarti Provash Chandra Sadhukhan 《Journal of virological methods》2013
Chikungunya and dengue, two arboviral infections are common in South-East Asia and their early clinical manifestations are very similar hence it is important to discriminate between them as early as possible for better clinical management. The aim of this study was to design a rapid, sensitive and specific method for the differential diagnosis of these two viruses simultaneously. A rapid one-tube duplex RT-PCR assay was developed that requires 110 min including RNA extraction, RT-PCR and agarose gel electrophoresis by using a novel Taq polymerase with high processivity. This one-tube duplex RT-PCR system with primers designed from the conserved regions of the genome allowed discrimination between the two viral groups. Bioinformatics analysis of the DNA sequences from PCR amplified products confirmed that this method was very specific and accurate. The time required for this duplex RT-PCR was comparable to the standard IgM capture ELISA method. This novel approach would help to diagnose specifically and accurately these two closely related arboviruses and enable early detection from blood. This method could be applied in resource limited settings, for surveillance in endemic regions or for routine epidemiological screening. 相似文献
98.
Kassandra Walluks Yuan Chen Cornelius Woelfel Linlin Yang Tiantian Cui Claudia Seliger Christiane Geier Thomas Knösel Sven Hauke Iver Petersen 《Pathology, research and practice》2013
Dermatofibrosarcoma protuberans (DFSP) is a dermal and subcutaneous tumor of intermediate malignancy. The most remarkable cytogenetic feature of DFSP is the chromosomal translocation t(17;22)(q22;q13), causing a fusion of the platelet-derived growth factor beta chain (PDGFB) gene at 22q13, and the collagen type 1 alpha 1 (COL1A1) at 17q22. The aim of the study was to analyze the molecular characteristic of DFSP in conjunction with histopathological and clinical features. 相似文献
99.
目的 通过抑制sox19b基因的表达,探讨sox19b基因在斑马鱼胚胎眼睛发育和形成中的作用。方法 通过显微注射sox19b 吗啉寡聚核苷酸(MO)抑制sox19b 基因的表达,观察胚胎发育过程中表型的变化;采用石蜡包埋组织切片及HE染色、RT-PCR和整封原位杂交等方法探讨敲除sox19b 后对斑马鱼胚胎眼睛发育的调控机制。 结果 敲除sox19b 基因后,斑马鱼胚胎眼睛发育受到影响,表现为眼睛变小或缺失,视网膜及晶状体结构发育异常(n =57/93);眼睛发育过程中重要调控基因 rx3、pax2a及 vsx2 等表达明显降低,进而影响眼睛的发育和形成。 结论 sox19b 基因作为转录调控因子,可以通过调节眼区转录因子的表达进而影响斑马鱼胚胎早期眼睛的发育和形成。 相似文献
100.
MDR1 gene expression and drug resistance of AML cells 总被引:5,自引:0,他引:5
Jan Maxwell NØrgaard Anne Bukh Sven Tyge Langkjer Niels Clausen Torben Palshof & Peter Hokland 《British journal of haematology》1998,100(3):534-540
We investigated the cellular drug resistance to aclarubicin (Acla), cytosine arabinoside (Ara-C), daunorubicin (Dau), doxorubicin (Dox), etoposide (Etop) and mitoxantrone (Mitox) using the MTT assay at time of disease presentation in 93 cases of acute myeloid leukaemia (AML). In 31 cases we concomitantly investigated MDR1 (multiple drug resistance 1 gene) expression (semi-quantitative competitive RT-PCR) of the leukaemic cells. Drug resistance towards Dau, Dox and Etop was correlated to the MDR1 expression of the AML cells ( P < 0.05) with high MDR1 expression being associated with high drug resistance towards these drugs. Although the data did not allow firm conclusions to be drawn on the correlation between MDR1 expression and drug resistance towards Ara-C and Mitox, the drug resistance towards Acla clearly was not correlated to, or dependent on, the MDR1 expression level of the AML blast cells. In addition, when examining the cross-activities among the six drugs distinct patterns emerged. Thus, high to very high degrees of cross-activity were found to exist between Dau, Dox, Etop and Mitox, whereas Ara-C had moderate cross-activity with the other drugs except Acla, which showed absent to moderate cross-activity with the other drugs. We conclude that MDR1 gene expression is of significance for cellular drug resistance towards specific (MDR1-related) drugs in AML, whereas it is not of significance regarding drug resistance towards other drugs, which is the case with the anthracycline Acla. We suggest that in the place of other more or less complicated ways to circumvent MDR1-mediated drug resistance, Acla may be used to replace Dau, Dox and other MDR1-related drugs if proven as potent as the drug it is to substitute. 相似文献