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1.
Autoimmune thyroid diseases (AITD) and Type 1 diabetes (T1D) frequently occur in the same individual pointing to a strong shared genetic susceptibility. Indeed, the co-occurrence of T1D and AITD in the same individual is classified as a variant of the autoimmune polyglandular syndrome type 3 (designated APS3v). Our aim was to identify new genes and mechanisms causing the co-occurrence of T1D + AITD (APS3v) in the same individual using a genome-wide approach. For our discovery set we analyzed 346 Caucasian APS3v patients and 727 gender and ethnicity matched healthy controls. Genotyping was performed using the Illumina Human660W-Quad.v1. The replication set included 185 APS3v patients and 340 controls. Association analyses were performed using the PLINK program, and pathway analyses were performed using the MAGENTA software. We identified multiple signals within the HLA region and conditioning studies suggested that a few of them contributed independently to the strong association of the HLA locus with APS3v. Outside the HLA region, variants in GPR103, a gene not suggested by previous studies of APS3v, T1D, or AITD, showed genome-wide significance (p < 5 × 10−8). In addition, a locus on 1p13 containing the PTPN22 gene showed genome-wide significant associations. Pathway analysis demonstrated that cell cycle, B-cell development, CD40, and CTLA-4 signaling were the major pathways contributing to the pathogenesis of APS3v. These findings suggest that complex mechanisms involving T-cell and B-cell pathways are involved in the strong genetic association between AITD and T1D.  相似文献   
2.
Aim of the workTo determine the clinical characteristics of ankylosing spondylitis (AS) in rheumatology wards in Togo. Patients and methods: The medical records of AS patients in four rheumatology wards in Togo were recorded from January 2000 to December 2019. Results: The study included 37 AS cases out of 35,304 rheumatic diseases patients’ files that were investigated over the preceding 20 years; accounting for 0.1% of hospital cases. Male predominance was noticed with a M:F ratio of 4.3. The mean age at disease onset was 29.6 ± 10.3 years and the mean duration of the symptoms was 9.5 ± 9.2 years. The clinical findings were dominated by spinal pain (91.9%). The main peripheral joints involvements were knees (48.6%) and ankles (35.1%) and the most frequent extra-articular features were ocular with conjunctivitis (13.5%) and uveitis (8.1%) respectively. Plain radiographs of the spine revealed syndesmophytes (45.9%) with bony ankylosis and bamboo spine (21.6%); and that of the pelvis showed sacroiliitis in 89.2%. The human leucocytic antigen (HLA B27) was positive in four cases. Non-steroidal anti-inflammatory drugs (NSAIDs) and sulfasalazine were the most commonly used drugs, respectively in 89.2% and 67.6% of patients. One patient was receiving biologic therapy. Conclusion: Ankylosing spondylitis is relatively rare in Togo. There is no particularity in the clinical features or imaging and laboratory findings. The diagnostic delay reflects the importance of the plain radiograph structural changes. NSAIDs and disease modifying anti-rheumatic drugs (DMARDs) are the cornerstone of the treatment due to their accessibility in Togo.  相似文献   
3.
目的探讨喉癌患者血小板表面血小板膜糖蛋白Ⅱb/Ⅲa纤维蛋白原受体(PAC-1)、血小板P-选择素(CD62P)阳性表达率以及与患者临床病理特征和复发的关系。方法选取2014年1月~2015年12月间在我院耳鼻喉科手术治疗的116例喉癌患者,随访≥2年,并选取同期在我院体检的健康人群60例为对照组,采用流式细胞仪检测法检测外周血PAC-1和CD62P阳性率,并分析与临床病理特征、复发的关系。结果喉癌患者PAC-1和CD62P阳性表达率分别为(17.82±1.76)%和(22.87±3.13)%,明显高于健康人群(P<0.05);而且在喉癌患者PAC-1表达和CD62P表达呈正相关性(r=0.238,P<0.05)。T3-T4分期或N2-N3分期患者PAC-1和CD62P阳性表达率高于T1-T2分期或N0-N1分期患者(P<0.05)。另外远处转移组PAC-1和CD62P阳性表达率高于未发生转移组(P<0.05);随访期间有24例患者复发,复发率为20.69%。复发喉癌患者PAC-1、CD62P阳性表达率分别为(17.02±0.85)%和(21.84±1.17)%,明显高于未复发的喉癌患者(P<0.05)。经Logistics回归分析,PAC-1和CD62P是喉癌患者复发的独立危险因素(P<0.05)。结论PAC-1和CD62P阳性表达率与喉癌患者T分期、淋巴结转移和远处转移密切相关,同时可作为喉癌局部复发、区域淋巴结转移、远处转移的预测指标。  相似文献   
4.
5.
《Human immunology》2020,81(9):550-552
We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 144 Mexicans from the state of Guerrero to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes in the state of Guerrero include eight Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in the state of Guerrero are Native American (61.36 ± 2.69% by ML; 54.17% of Native American haplotypes) and European (35.01 ± 4.59% by ML; 32.29% of European haplotypes), and a relatively low African genetic component (3.63 ± 2.38% by ML; 5.90% of African haplotypes).  相似文献   
6.
7.
Transplanting the Highly Sensitized Patient: The Emory Algorithm   总被引:4,自引:0,他引:4  
Renal transplant patients sensitized to HLA antigens comprise nearly one-third of the UNOS wait-list and receive 14% of deceased donor (DD) transplants, a rate half that of unsensitized patients. Between 1999 and 2003, we performed 492 adult renal transplants from DD; 120 patients (approximately 25%) had a panel reactive antibody (PRA) of >30%, with nearly half (n = 58) having a PRA of >80%. Our approach is based upon high-resolution solid-phase HLA antibody analysis to identify class I/II antibodies and a 'virtual crossmatch' to predict compatible donor/recipient combinations. Recipients are excluded from the United Network for Organ Sharing match run if donors possess unacceptable antigens. Thus, when sensitized patients appear on the match run, they have a high probability of a negative final crossmatch. Here, we describe our 5-year experience with this approach. Five-year graft survival ranged from 66% to 70% among unsensitized (n = 272), moderately sensitized (PRA < 30%, n = 100) and highly sensitized (>30% PRA; n = 120) patients, equal to the average national graft survival (65.7%). The application of this approach (the Emory Algorithm) provides a logical and systematic approach to improve the access of sensitized patients to DD organs and promote more equitable allocation to a highly disadvantaged group of patients awaiting renal transplantation.  相似文献   
8.
Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.  相似文献   
9.
Forty-one multiplex families, from published sources and new data from the National Cancer Institute, segregating for Hodgkin's disease and HLA, have been studied. A reanalysis of these data strongly suggests a recessive mode of inheritance for susceptibility to Hodgkin's disease. The HLA haplotype sharing data between affected relatives demonstrate that approximately 60% of cases in multiplex families are due to an HLA-linked susceptibility gene, the remaining 40% being due to other familial factors. The data clearly support the hypothesis of etiological heterogeneity for Hodgkin's disease, with both HLA-linked and HLA-unlinked factors being responsible. Finally, there is an increased concordance of histological types between affected relatives, but this concordance seems independent of HLA sharing.  相似文献   
10.
目的 探讨血管紧张素Ⅱ(AngⅡ)1型受体拮抗剂(ARB)洛沙坦对代谢综合征(MS)肾组织环氧化酶2(COX-2)表达的影响及其机制。 方法 把7周大的MS模型肥胖Zucker大鼠随机分成洛沙坦处理组和未处理组,以瘦Zucker大鼠为对照组,连续给药4个月后观察肾组织内COX-2的表达。另外,用AngⅡ刺激6 h的系膜细胞和用从微型渗透泵灌注AngⅡ 5 d的C57BL/6小鼠肾脏提取的肾皮质,观察COX-2的表达。采用RT-PCR和Western印迹法分别检测COX-2 mRNA和蛋白的表达。 结果 洛沙坦可阻止肥胖Zucker大鼠肾组织内COX-2表达增加。AngⅡ直接刺激可以诱导系膜细胞和肾组织内COX-2表达增加。 结论 AngⅡ可以调控MS肾组织内COX-2表达增加。ARB可以通过抑制COX-2的表达保护MS肾脏,这对应用非COX-2抑制剂来保护MS肾脏具有重要的意义。  相似文献   
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