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《Immunobiology》2020,225(2):151876
Acute graft-versus-host disease (aGVHD) is a severe inflammatory complication of haematopoeitic stem cell transplantation. The nuclear factor- Kappa Beta (NF-κB) signaling pathway regulates T cell activation. The NF-κB controls the expression of microRNA-146a (miR-146a) that in turn regulates NF-κB activation through a negative feedback loop. We aim to analyze the association between NF-κB1 encoding p50 (rs28362491, −94 in.ertion/deletion ATTG) and miR-146a (rs2910164, G > C) polymorphisms and risk of aGVHD. Genotyping was performed for 135 HLA-matched donors using polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP).The incidence of aGVHD grades II-IV was 24/135 (17.8 %). NF-κB1 genotype and cytomegalovirus infection were significantly associated with risk of aGVHD II-IV (p = 0.022, HR = 3.17, 95 % CI:1.18-8.51 and p = 0.048, HR = 2.56, 95 % CI:1.01–6.52, respectively). In multivariate analysis, NF-κB1homozygous deletion/deletion genotype was the only independent risk factor associated with aGVHD II-IV (p = 0.013, HR = 3.50, 95 % CI:1.30–9.44). No significant association could be observed between miR-146a polymorphism and aGVHD. Combined NF-κB1 and miR146a genotype analysis warrants investigation in a larger cohort. Our preliminary data do not support the association between miR146a and aGVHD, but suggest an association between NF-κB1 and risk of aGVHD that may pave the way for the development of a novel targeted therapy if proved in a larger cohort.  相似文献   
94.
《Immunobiology》2020,225(2):151900
BackgroundNK cells as a part of innate immune system, are controlled by a set of activating and inhibitory KIR receptors (aKIR, iKIR) which are implicated in tumor microenvironment immunity through a variety of activating and inhibitory immune signals. KIRs are multi gene family receptors that differ in the number and type of genes among individuals. In the current research we determined the KIRs genes and genotypes impact on predisposition to meningioma development in Iranians.MethodsSequence-specific primers-polymerase chain reaction (SSP-PCR) was performed for genotyping of 16 KIRs in 159 meningioma cases and 362 age and sex matched healthy controls (CNs) at Shiraz Institute for Cancer Research.ResultsComparison of the KIR genotypes frequencies between cases and controls disclosed a highly significant increase in Bx genotype, CxTx subset and Cen AB and Tel AB in meningioma cases and a decrease in AA genotype, C4Tx subset and Cen AA, Tel AA, Tel BB in healthy controls.Among all 16 KIR genes, the carriers of KIR2DL5 and KIR2DS5 constituted a much greater proportion in meningioma than control group. Comparison of carrier frequencies of KIR2DS4 variants between case and controls revealed a higher frequency of KIR2DS4 full length (KIR2DS4fl) in meningioma cases and a lower frequency of KIR2DS4 deleted variant (KIR2DS4del) in controls. Furthermore, the simultaneous presence of 2DS5, 2DS4fl, CenAB, TelAB and absence of 2DS4del, CenAA, TelAA, TelBB, magnify the risk of developing meningioma substantially (OR ≈ 23). Altogether, 41 distinct KIR genotypes were characterized in 521 subjects. Among them, some individuals were characterized by seven peculiar genotypes that the linkage disequilibrium between KIR2DS2-KIR2DL2 and KIR2DL5-KIR2DS3-KIR2DS5 has not been detected. The carriers of certain genotypes with presence of as KIR2DL5 and absence of KIR2DS3, KIR2DS5 constituted a much higher proportion in meningioma than control group which increase the risk of meningioma up to 72 times.ConclusionThis case- control study suggests carriers of Bx genotype, KIR2DL5, KIR2DS5, 2DS4fl, ≥ 4 iKIR, CxTx subset as well as Cen AB and Tel AB are associated with an increased risk of developing meningioma whereas carrying KIR2DS4del, AA, C4TX genotypes and Cen AA, Tel AA, Tel BB reduce the genetic predisposition for meningioma.  相似文献   
95.
目的分离、鉴定口腔变黑普雷沃氏菌(Prevotella nigrescens,P.nigrescens),探讨其对食管鳞癌是否有促进作用。方法胰豆胨肝粉琼脂(GAM)培养基厌氧原代培养慢性牙周炎患者龈沟液,挑选黑色菌落分离纯化;革兰染色、16S rRNA基因测序鉴定分离的单克隆细菌;该细菌感染食管鳞癌细胞NE6-T后细胞生物学性状变化。结果慢性牙周炎患者龈沟液厌氧原代培养120 h后可见多个菌落,其中灰黑色菌落经连续划线法分离纯化为黑色、圆形光滑单克隆菌落。该细菌革兰染色阴性、串珠状排列,16S rDNA序列与P.nigrescens F0103同源性为99.78%(P.nigrescens LY01)。LY01感染促进NE6-T细胞体外增殖、迁移、侵袭和裸鼠皮下荷瘤生长,并诱导Ki67表达上调和p-STAT3激活。结论慢性牙周炎口腔P.nigrescens可能促进了食管鳞癌发展。  相似文献   
96.
Hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome (LS), is a common cancer-predisposing syndrome. This study aimed to investigate the spectrum of germ-line mutations in Russian LS patients. LS-related mismatch repair (MMR) genes were analyzed in 16 patients, who were forwarded to genetic testing due to strong clinical features of LS and had high-level microsatellite instability (MSI-H) in the tumor (n = 14) or unknown MSI status (n = 2). In addition, 672 consecutive colorectal cancer (CRC) cases were screened for family history; 15 patients were younger than 50 years and reported 2 or more instances of LS-related cancers in 1st- or 2nd-degree relatives. Seven of these cases demonstrated MSI-H and therefore were subjected to DNA germ-line testing. Overall, 17/23 (74%) subjects carried LS-associated gene variants (MLH1: 10; MSH2: 4; MSH6: 2; PMS2: 1), with 2 alleles (MLH1 c.677G > T and MSH2 с.1906G > C) detected twice. Testing for recurrent mutations of 30 consecutive MSI-H CRCs led to the identification of 2 additional subjects with LS. The analysis of all relevant publications identified 28 unrelated LS patients presented in Russian medical literature and 3 unrelated Russian LS subjects described in international journals. Overall, 15/49 (31%) genetic defects revealed in Russian LS patients were represented by six recurrent alleles (MLH1: c.350C > T, c.677G > T, c.1852_1854del; MSH2: c.942+3A > T, c.1861C > T, с.1906G > C). We conclude that the founder effect for LS in Russia is seemingly less pronounced than the one for hereditary breast-ovarian cancer syndrome, however testing for recurrent LS mutations may be considered feasible in some circumstances.  相似文献   
97.
The etiological role of human papillomavirus (HPV) in cervical cancer has been well established. However, it is inconclusive whether HPV plays the same role in esophageal carcinogenesis. In this study, we detected HPV infection in 145 frozen esophageal tissues, including 30 normal epithelium (ENOR), 37 dysplasia (DYS) and 78 invasive squamous cell carcinoma (ESCC), and in 143 frozen cervical tissues composed of 30 normal epithelium (CNOR), 38 intraepithelial neoplasia (CIN) and 75 invasive squamous cell carcinoma (CSCC). The patients and symptom-free subjects enrolled in this study were from a high-incidence area for both ESCC and CSCC, Linzhou City, Northern China, from 2007 to 2009. The HPV infection analysis was conducted by using an HPV GenoArray Test Kit. We found that the high-risk HPV types accounted for more than 90 % of the HPV-positive lesions of esophagus and cervix tissues. The prevalence of high-risk HPV types increased significantly during the progression of both esophageal and cervical carcinogenesis (positive rate in esophageal tissues: 33 % ENOR, 70 % in DYS and 69 % in ESCC; positive rate in cervical tissues: 27 % in CNOR, 82 % in CIN and 88 % in CSCC; P < 0.001, respectively). Infection with the high-risk HPV types increased the risk for both DYS and ESCC by 4-fold (DYS vs. ENOR: OR = 4.73, 95 %CI = 1.68-13.32; ESCC vs. ENOR: OR = 4.50, 95 %CI = 1.83-11.05) and increased the risk for both CIN and CSCC by 12-fold and 20-fold (CIN vs. CNOR: OR = 12.18, 95 %CI = 3.85-38.55; CSCC vs. CNOR: OR = 20.17, 95 %CI = 6.93-58.65), respectively. The prevalence of high-risk types in ESCC patients was lower than that in CSCC patients (P = 0.005) and was significantly associated with the degree of ESCC tumor infiltration (P = 0.001). HPV 16 was the most prevalent subtype in both esophageal and cervical tissues. Single HPV infection increased significantly along with the progression of ESCC and maintained a high level in cervical tissues, regardless of whether they were CNOR or CSCC tissues. Our results showed that infection with HPV, especially the high-risk types, was positively associated with both esophageal and cervical cancers, suggesting that HPV also plays a role in the etiology of ESCC in the high-incidence area.  相似文献   
98.
Lung cancer is a leading cause of cancer deaths worldwide. Development of lung cancer is associated with exposure to carcinogens such as tobacco smoke and some environmental factors. The incidence of lung cancer increases with age, particularly after age 60. It was estimated that less than 2% of all lung cancer cases occurred in patients younger than 45; therefore, this type of tumor can be considered as an aging-related disease. MicroRNAs (miRNAs) are small non-coding RNA molecules capable of regulating expression of over 50% of protein-coding genes. miRNAs were shown to play an extremely important role in cell functioning, affecting all biological processes, as well as development of various diseases. Expression profiles of miRNAs are known to be altered in cancer, including lung cancer, and also exhibit changes during aging. These RNA molecules are stable in tissue sections and blood and reflect tumor origin, histotype, and stage, which make them candidate diagnostic and prognostic biomarkers. miRNA mimetics or inhibitors can be delivered into a cell, with possible therapeutic implications. Here, we review the results obtained during the last several years that demonstrate the aging-related regulation of miRNAs expression, in association with their role in lung cancer initiation, progression, and resistance to anticancer therapy, as well as the possibility to use miRNAs as predictive biomarkers for treatment response.  相似文献   
99.
This study is to detect the co-expression of embryonic stem cell-related markers (Oct4 and Sox2) in the carcinogenesis of oral mucosa. The expression profile of these markers was studied by immunohistochemistry assay in rat and human samples. The normal oral mucosa (20 cases) and the transforming oral mucosa (20 cases) were performed in rat samples. The precancerous lesions (20 cases), OSCCs in primary site (116 cases), corresponding epithelial non-cancer tissues adjacent to the OSCC (20 cases) and 46 paired metastatic OSCCs in lymph nodes were performed in human samples. The co-expression of the two markers was defined as both of them are positively detected in the same site of one case under one selected field of microscope. The results indicated that Oct4 and Sox2 were individually detected in normal oral mucosa, but they cannot be co-expressed in the same site of one case. The co-expression of Oct4 and Sox2 (Oct4+Sox2+) was frequently detected in the transforming oral mucosa of rat (16/20), precancerous lesions of human (12/20) and epithelial non-cancer tissues adjacent to the OSCC (18/20). Also, Oct4+Sox2+ profile was remarkable noted in the primary sites of OSCCs (38/116). In the 46 paired OSCCs (primary sites with lymph node metastasis), Oct4+Sox2+ profile (8/46) was less frequently detected than Oct4low/-Sox2low/- (14/46) profile in the metastatic sites. To conclude, this study suggests Oct4 and Sox2 are expressed in normal oral mucosa, premalignant diseases, primary sites of OSCCs and metastasis sites of OSCCs. Oct4+Sox2+ profile may contribute to the malignant transformation of oral mucosa.  相似文献   
100.
Objectives: To evaluate the clinical value of acridine orange fluorescent staining in urinary cytology for the diagnosis of upper urinary tract urothelial carcinoma. Methods and materials: A retrospective analysis was conducted with 510 cases of upper urinary tract urothelial carcinoma (UTUC) in terms of the results of acridine orange fluorescence (AO-F) staining of the exfoliated cells in urine. The percentage of positive AO-F result and the positive predictive value of AO-F for high-grade and muscle invasive urothelial carcinoma were calculated and analyzed in terms of clinical characteristics. Results: The overall percentage of positive AO-F result was 49% in the 510 patients, 54.1% for males and 40.6% for females. AO-F was positive in 51.9% of the patients with hematuria and 36.2% of the patients without hematuria. AO-F was positive in 56.4% of the patients with renal pelvis carcinoma and 42.8% of the patients with ureteral cancer; in 44.6% of the patients with non-muscle invasive carcinoma and 53.5% of the patients with muscle-invasive carcinoma. AO-F was positive in 26.8% of the cases with low-grade carcinoma and 55.3% of the patients with high-grade carcinoma. The positive predictive value of AO-F was 88% for high-grade cancer, and only 53.6% for muscle invasive carcinoma. Conclusions: Acridine orange fluorescence microscopy cannot increase the sensitivity of urine exfoliative cytology in the diagnosis of UTUC. It may be used as a predictor of high-grade UTUC. Acridine orange fluorescence microscopy in urinary cytodiagnosis does not show high value in predicting muscle invasive UTUC.  相似文献   
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