全文获取类型
收费全文 | 808篇 |
免费 | 46篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 44篇 |
妇产科学 | 9篇 |
基础医学 | 76篇 |
口腔科学 | 30篇 |
临床医学 | 152篇 |
内科学 | 179篇 |
皮肤病学 | 15篇 |
神经病学 | 26篇 |
特种医学 | 143篇 |
外科学 | 46篇 |
综合类 | 17篇 |
预防医学 | 29篇 |
眼科学 | 2篇 |
药学 | 95篇 |
中国医学 | 2篇 |
肿瘤学 | 23篇 |
出版年
2022年 | 3篇 |
2021年 | 9篇 |
2020年 | 7篇 |
2019年 | 6篇 |
2018年 | 15篇 |
2017年 | 8篇 |
2016年 | 14篇 |
2015年 | 14篇 |
2014年 | 31篇 |
2013年 | 34篇 |
2012年 | 22篇 |
2011年 | 17篇 |
2010年 | 30篇 |
2009年 | 44篇 |
2008年 | 14篇 |
2007年 | 34篇 |
2006年 | 22篇 |
2005年 | 13篇 |
2004年 | 12篇 |
2003年 | 10篇 |
2002年 | 13篇 |
2001年 | 6篇 |
2000年 | 12篇 |
1999年 | 28篇 |
1998年 | 36篇 |
1997年 | 40篇 |
1996年 | 39篇 |
1995年 | 25篇 |
1994年 | 39篇 |
1993年 | 23篇 |
1992年 | 11篇 |
1991年 | 12篇 |
1990年 | 8篇 |
1989年 | 23篇 |
1988年 | 25篇 |
1987年 | 18篇 |
1986年 | 20篇 |
1985年 | 12篇 |
1984年 | 15篇 |
1983年 | 10篇 |
1982年 | 15篇 |
1981年 | 16篇 |
1980年 | 14篇 |
1979年 | 3篇 |
1978年 | 7篇 |
1977年 | 13篇 |
1976年 | 19篇 |
1975年 | 10篇 |
1974年 | 9篇 |
1972年 | 4篇 |
排序方式: 共有889条查询结果,搜索用时 3 毫秒
91.
Sadeghi-Abdollahi B Eshaghi A Hosseini SN Ghahremani M Davatchi F 《International journal of rheumatic diseases》2012,15(2):144-153
Aim: Low back pain (LBP) is the second most frequent reason for seeking medical advice. Various treatments are proposed from no intervention, to analgesics, rest, exercises, local interventions and surgical procedures. Results and outcomes are differently reported. Back School (BS), a combination of patient education and physical exercises, seems to have good results. The aim of this study was to check the effect of BS in factory workers. Patients and Methods: All (70) workers were interviewed and 26 of them (37.1%) had chronic LBP. Secondary causes were excluded. Anatomy, physiology, biomechanics of the spine, correct postures at work and back exercises were taught. Pain on a visual analog scale (VAS) of 0–100, and Short Form (SF)‐36 health survey were applied, before, at the end of BS sessions, and 3 months after BS. Analysis was done by t‐test, Wilcoxon and Pearson’s correlation test. Results: The mean VAS on pain before BS was 43.4 ± 22.3, improving to 38.6 ± 17.5 at the end of BS. The difference was not significant (P = 0.19). The mean VAS improved to 27.5 ± 20 at 3 months after BS. The difference was significant compared to before BS (P = 0.001). The quality of life measured by the SF‐36 questionnaire, did not improve significantly, except for two of its eight subgroups (Role Physical, Social Functioning) at the end of BS, and two of its subgroup (Mental Health, Social Functioning) at 3 months after BS. Conclusion: Among industrial workers, BS is mainly effective on pain, but is less evident on SF‐36. 相似文献
92.
Multiple tumor-suppressor gene 1 inactivation is the most frequent genetic alteration in T-cell acute lymphoblastic leukemia 总被引:6,自引:1,他引:6
No constant genetic alteration has yet been unravelled in T-cell acute lymphoblastic leukemia (T-ALL), and, to date, the most frequent alteration, the SIL-TAL1 deletion, is found in approximately 20% of cases. Recently, two genes have been identified, the multiple tumor- suppressor gene 1 (MTS1) and multiple tumor-suppressor gene 2 (MTS2), whose products inhibit cell cycle progression. A characterization of the MTS locus organization allowed to determine the incidence of MTS1 and MTS2 inactivation in T-ALL. MTS1 and MTS2 configurations were determined by Southern blotting using 8 probes in 59 patients with T- ALL (40 children and 19 adults). Biallelic MTS1 inactivation by deletions and/or rearrangements was observed in 45 cases (76%). Monoallelic alterations were found in 6 cases (10%). The second MTS1 allele was studied in the 4 cases with available material. A point mutation was found in 2 cases. The lack of MTS1 mRNA expression was observed by Northern blot analysis in a third case. A normal single- strand conformation polymorphism pattern of MTS1 exons 1alpha and 2 was found and MTS1 RNA was detected in the fourth case, but a rearrangement occurring 5' to MTS1 exon 1 alpha deleting MTS1 exon 1Beta was documented. One case presented a complex rearrangement. Germline configuration for MTS1 and MTS2 was found in only 7 cases. The localization of the 17 breakpoints occurring in the MTS locus were determined. Ten of them (59%) are clustered in a 6-kb region located 5 kb downstream to the newly identified MTS1 exon 1Beta. No rearrangement disrupting MTS2 was detected and more rearrangements spared MTS2 than MTS1 (P<.01). MTS1 but not MTS2 RNA was detected by Northern blotting in the human thymus. These data strongly suggest that MTS1 is the functional target of rearrangements in T-ALL. MTS1 inactivation, observed in at least 80% of T-ALL, is the most consistent genetic defect found in this disease to date. 相似文献
93.
94.
Mackinnon S; Papadopoulos EB; Carabasi MH; Reich L; Collins NH; Boulad F; Castro-Malaspina H; Childs BH; Gillio AP; Kernan NA 《Blood》1995,86(4):1261-1268
Infusions of large numbers (> 10(8)/kg) of donor leukocytes can induce remissions in patients with chronic myeloid leukemia (CML) who relapse after marrow transplantation. We wanted to determine if substantially lower numbers of donor leukocytes could induce remissions and, if so, whether this would reduce the 90% incidence of graft-versus-host disease (GVHD) associated with this therapy. Twenty-two patients with relapsed CML were studied: 2 in molecular relapse, 6 in cytogenetic relapse, 10 in chronic phase, and 4 in accelerated phase. Each patient received escalating doses of donor leukocytes at 4- to 33-week intervals. Leukocyte doses were calculated as T cells per kilogram of recipient weight. There were 8 dose levels between 1 x 10(5) and 5 x 10(8). Lineage-specific chimerism and residual leukemia detection were assessed using sensitive polymerase chain reaction (PCR) methodologies. Nineteen of the 22 patients achieved remission. Remissions were achieved at the following T-cell doses: 1 x 10(7) (n = 8), 5 x 10(7) (n = 4), 1 x 10(8) (n = 3), and 5 x 10(8) (n = 4). To date, 15 of the 17 evaluable patients have become BCR-ABL negative by PCR. The incidence of GVHD was correlated with the dose of T cells administered. Only 1 of the 8 patients who achieved remission at a T-cell dose of 1 x 10(7)/kg developed GVHD, whereas this complication developed in 8 of the 11 responders who received a T-cell dose of > or = 5 x 10(7)/kg. Three patients died in remission, 1 secondary to marrow aplasia, 1 of respiratory failure and 1 of complications of chronic GVHD. Sixteen patients who were mixed T-cell chimeras before treatment became full donor T-cell chimeras at the time of remission. Donor leukocytes with a T-cell content as low as 1 x 10(7)/kg can result in complete donor chimerism together with a potent graft-versus-leukemia (GVL) effect. The dose of donor leukocytes or T cells used may be important in determining both the GVL response and the incidence of GVHD. In many patients, this potent GVL effect can occur in the absence of clinical GVHD. 相似文献
95.
Agonist-induced inside-out signaling results in an increased affinity of integrin alpha IIb beta 3 (platelet glycoprotein IIb-IIIa) for soluble ligands (fibrinogen [Fg] and PAC1). Ligand binding to integrins initiates outside-in signaling that leads to cellular responses such as cell spreading and focal adhesion formation. A point mutation in the beta 3 cytoplasmic domain (S752-->P) is associated with blocked inside- out alpha IIb beta 3 signaling in a variant Glanzmann's thrombasthenia. This mutation was introduced into beta 3 and cotransfected into Chinese hamster ovary cells with a chimeric alpha subunit consisting of the alpha IIb extracellular and transmembrane domains and the alpha 6B cytoplasmic domain. The substitution of the alpha IIb cytoplasmic domain with that of alpha 6 led to activation of alpha IIb beta 3 to bind PAC1, mimicking inside-out signaling. This effect was reversed by the S752-->P mutation, indicating a disruption of inside-out signaling by the mutation. In addition, transfectants expressing this beta 3 variant showed reduced alpha IIb beta 3-mediated cell spreading on immobilized Fg, focal adhesion, and fibrin clot retraction, suggesting an impairment in outside-in alpha IIb beta 3 signaling. Therefore, a single point mutation in the beta 3 cytoplasmic domain impaired bidirectional signaling through alpha IIb beta 3. 相似文献
96.
Molecular basis of the heterogeneity of expression of glycosyl phosphatidylinositol anchored proteins in paroxysmal nocturnal hemoglobinuria 总被引:2,自引:3,他引:2
Endo M; Ware RE; Vreeke TM; Singh SP; Howard TA; Tomita A; Holguin MH; Parker CJ 《Blood》1996,87(6):2546-2557
The purpose of these studies was to determine the molecular basis of the phenotypic mosaicism that is a defining feature of paroxysmal nocturnal hemoglobinuria (PNH). Analysis of T cell clones from a female patient revealed four distinct phenotypes based on surface expression of glycosyl phosphatidylinositol-anchored proteins (GPI-AP). When PIG-A (the gene that is mutant in PNH) from these clones was analyzed, four discrete somatic mutations were identified. Analysis of X chromosomal inactivation among the abnormal T cell clones was consistent with polyclonality. Together, these studies demonstrate that the phenotypic mosaicism that is characteristic of PNH is a consequence of genotypic mosaicism and that, at least in this case, PNH is a polyclonal rather than a monoclonal disease. That four distinct somatic mutations were present in a single patient suggests that in conditions that predispose to PNH PIG-A may be hypermutable. 相似文献
97.
Ghavamzadeh A Alimoghadam K Nasseri P Jahani M Khodabandeh A Ghahremani G 《Bone marrow transplantation》1999,23(3):299-301
Dyskeratosis congenita is recognized by its dermal lesions and constitutional aplastic anemia in some cases. We report successful allogeneic bone marrow transplantation in two siblings with this disease from their sister, and their long term follow-up. We used reduced doses of cyclophosphamide and busulfan for conditioning instead of total body irradiation. Also, we report late adverse effects of transplantation which are not distinguishable from the natural course of disease. 相似文献
98.
O Falusi AL French EC Seaberg PC Tien DH Watts H Minkoff E Piessens A Kovacs K Anastos MH Cohen 《Clinical infectious diseases》2002,35(11):1414-1417
We assessed the prevalence and predictors of latent Toxoplasma infection in a large group of human immunodeficiency virus (HIV)-infected and HIV-uninfected at-risk US women. The prevalence of latent Toxoplasma infection was 15% (380 of 2525 persons) and did not differ by HIV infection status. HIV-infected women aged > or =50 years and those born outside of the United States were more likely to have latent Toxoplasma infection, with prevalences of 32% and 41%, respectively. 相似文献
99.
100.