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641.
We aimed to fill the literature gap by identifying the clinical benefits of aromatherapy in older adults with dementia, and its efficacy in reducing behavioral and psychological symptoms of dementia (BPSD) based on available randomized controlled trials (RCT). A systematic review of 11 clinical trials shortlisted from electronic databases from 1995 to 2011 was carried out. The RCT showed that aromatherapy had positive effects on reduction of BPSD, improvement in cognitive functions, increasing quality of life, enhancing independence of activities of daily living and so on. However, adverse effects were noted in some studies. Limitations on methodology are discussed and suggestions on directions of further studies are made. It is recommended that aromatherapy shows the potential to be applied as a therapeutic and safe complementary and alternative therapy for the management of BPSD on more evidence collected from better designed RCT. Geriatr Gerontol Int 2012; 12: 372–382.  相似文献   
642.
Biotinylated interleukin-4 (IL-4) was used to examine IL-4 receptor (IL- 4R) expression on a range of human B-cell lines by flow cytometry. Using high concentrations of biotinylated IL-4, we have identified a novel low-affinity IL-4 receptor expressed at high levels on pre-B lines. Expression of this low-affinity receptor did not correlate with detected mRNA levels for the previously cloned receptor or with reactivity of two anti-human IL-4R monoclonal antibodies (MoAb). Radiolabeled IL-4 cross-linking studies using pre-B lines showed a doublet of 65 to 75 Kd in contrast to the 110- to 130-Kd molecule detected on cells expressing the cloned IL-4R. A soluble IL-4 binding protein (IL-4bp) was purified from the supernatants of three pre-B lines expressing the low-affinity receptor on their surface. IL-4bp could block both IL-4-mediated CD23 induction on tonsil B cells and IL- 4-induced inhibition of proliferation of the pre-B line JM1. Partial N- terminal amino acid sequence was obtained from purified IL-4bp that confirmed this protein to be novel. A 12 amino acid peptide based on the IL-4bp sequence was used to produce a polyclonal antiserum that was reactive with purified IL-4bp, and also bound to the surface of pre-B cells but not to murine CTLL cells transfected with the human IL-4R. Blocking MoAb against the previously characterized high-affinity receptor inhibited IL-4-mediated proliferation of hIL-4R+ CTLL cells but had no effect on IL-4-induced inhibition of JM1 cell proliferation, and only partially inhibited IL-4-mediated CD23 and sIgM induction and proliferation of tonsil B cells. The data presented here provide evidence for a novel cell-surface expressed low-affinity IL-4R that also exists as a biologically active soluble IL-4 binding protein.  相似文献   
643.
The aim of this investigation was to identify domains of collagen type I that can support platelet adhesion under flow conditions. Four cyanogen bromide (CB) fragments composing 87% of the collagen alpha 1(I)-chain were studied under static and flow conditions. Under static conditions, bovine and human collagen fragment alpha 1(I)CB3 induced aggregate formation, whereas alpha 1(I)CB7 and alpha 1(I)CB8 supported adhesion of dendritic and contact platelets. Bovine alpha 1(I)CB6 weakly supported platelet adhesion. At shear rate 300/s, collagen fragment alpha 1(I)CB3 strongly supported platelet adhesion, whereas lower platelet adhesion was observed to alpha 1(I)CB7 and alpha 1(I)CB8. The fragment alpha 1(I)CB6 did not support platelet adhesion under flow conditions. Adhesion to alpha 1(I)CB3 was completely inhibited by a low concentration (0.6 IgG microgram/mL) of anti-GPIa monoclonal antibody (MoAb), whereas this concentration of antibody partially inhibited adhesion to alpha 1(I)CB7 and alpha 1(I)CB8. At higher concentrations (3 micrograms/mL) the anti-glycoprotein Ia (GPIa) antibody completely inhibited adhesion to alpha 1(I)CB8 and further reduced adhesion to alpha 1(I)CB7. Platelet adhesion to alpha 1(I)CB3, alpha 1(I)CB7, and alpha 1(I)CB8 was strongly inhibited by an anti-GPIb MoAb. A MoAb against the GPIb-binding site of von Willebrand factor (vWF) strongly inhibited platelet adhesion to alpha 1(I)CB7 and alpha 1(I)CB8, whereas platelet adhesion to alpha 1(I)CB3 was not inhibited. We conclude that under flow conditions alpha 1(I)CB3, alpha 1(I)CB7, and alpha 1(I)CB8 support GPIa/IIa-dependent platelet adhesion. The GPIb-vWF interaction is important under flow conditions for adhesion to alpha 1(I)CB7 and alpha 1(I)CB8 and probably also to alpha 1(I)CB3.  相似文献   
644.
The Ws mutant allele of rats represents a 12-base deletion at the tyrosine kinase domain of the c-kit gene. Although homozygous Ws/Ws rats were deficient in both connective tissue-type mast cells (CTMC) and mucosal-type mast cells (MMC), mast cells did develop when bone marrow cells of Ws/Ws rats were cultured in the presence of concanavalin A-stimulated spleen cell conditioned medium (ConA-SCM). Although the proliferative response of rat cultured mast cells (RCMC) derived from Ws/Ws rats to ConA-SCM was comparable to that of RCMC derived from control normal (+/+) rats, the proliferative response of Ws/Ws RCMC to rat recombinant stem cell factor (rrSCF; a ligand for the c-kit receptor tyrosine kinase) was much lower than that of +/+ RCMC. However, a slight c-kit kinase activity was detectable in Ws/Ws RCMC, and the proliferation of Ws/Ws RCMC was accelerated when rrSCF was added to ConA-SCM. Because CTMC contain rat mast cell protease-I (RMCP- I) and MMC contain RMCP-II, the phenotype of +/+ and Ws/Ws RCMC in various culture conditions was evaluated by immunohistochemistry of RMCPs. Both +/+ and Ws/Ws RCMC showed the MMC-like phenotype (RMCP-I- /II+) when they were cultured with ConA-SCM alone. Most +/+ RCMC and about half of Ws/Ws RCMC acquired a novel protease (RMCP-I+/II+) phenotype when they were cultured with rrSCF alone. However, because the number of Ws/Ws RCMC dropped to one-tenth in the medium containing rrSCF alone, the absolute number of Ws/Ws RCMC with the RMCP-I+/II+ phenotype did not increase significantly. The effect of rrSCF in inducing the novel phenotype was suppressed when ConA-SCM was added to rrSCF. In contrast, +/+ and Ws/Ws RCMC cocultured with +/+ fibroblasts showed the RMCP-I+/II+ phenotype even in the presence of ConA-SCM. Moreover, a fibroblast cell line derived from SI/SI mouse embryos that did not produce SCF did not support the survival of both +/+ and Ws/Ws RCMC but did induce the RMCP-I+/II+ phenotype in about half of +/+ and Ws/Ws RCMC when their survival was supported by the addition of ConA- SCM. The normal signal transduction through the c-kit receptor did not appear to be prerequisite for the acquisition of the RMCP-I+/II+ phenotype.  相似文献   
645.
Kalra  R; Paderanga  DC; Olson  K; Shannon  KM 《Blood》1994,84(10):3435-3439
Children with neurofibromatosis, type 1 (NF-1) are at increased risk of developing malignant myeloid disorders and their bone marrows frequently show loss of the normal allele of the NF1 tumor-suppressor gene. NF1 encodes a protein called neurofibromin, which accelerates guanosine triphosphate (GTP) hydrolysis on the p21ras (Ras) family of signaling proteins. We used a genetic approach to test the hypothesis that NF1 negatively regulates myeloid cell growth through its effect on Ras. This model predicts that, if RAS mutations and loss of NF1 function deregulate myeloid growth by the same biomechanical mechanism, then activating RAS mutations will be restricted to children with malignant myeloid disorders who do not have NF-1. We studied 71 children, including 28 with bone marrow monosomy 7 syndrome (Mo7), 35with juvenile chronic myelogenous leukemia (JCML), three with other forms of preleukemia, and five with acute myelogenous leukemia (AML), for activating mutations of KRAS and NRAS. The incidence of RAS mutations was 21% (12 of 55) in patients without NF-1 and 0% (zero of 16) in children with NF-1 (P = .04). Among the 55 patients who did not have NF-1, we found RAS mutations in four of 27 with Mo 7, in five of 24 with JCML, in two of 3 with AML, and in a patient with myeloproliferative syndrome (MPS). These data from primary human cancer cells provide strong genetic evidence that NF1 limits the growth of myeloid cells by regulating Ras.  相似文献   
646.
The prognostic significance of c-kit receptor expression on leukemic blast cells was determined in 122 children with acute myeloid leukemia (AML) entered onto Childrens Cancer Group protocol 213. Clinical and laboratory characteristics as well as outcome were analyzed according to the percentage of blast cells expressing c-kit receptors and the relative number of c-kit receptors per cell as determined by indirect immunofluorescence. c-kit receptor expression was strongly associated with the expression of the CD34 antigen. However, contrary to findings in adult patients with AML, c-kit receptor expression by childhood AML blast cells was not predictive of a poor response to therapy.  相似文献   
647.
Baumler  CB; Bohler  T; Herr  I; Benner  A; Krammer  PH; Debatin  KM 《Blood》1996,88(5):1741-1746
Increased apoptosis of CD4+ T cells is considered to be involved in CD4+ T-cell depletion in human immunodeficiency virus type-1 (HIV-1)- infected individuals progressing toward acquired immunodeficiency syndrome (AIDS). We have recently shown that CD95 (APO-1/Fas) expression is strongly increased in T cells of HIV-1-infected children. In this report we provide further evidence for a deregulated CD95 system in AIDS. CD95 expression in HIV-1+ children is not restricted to previously activated CD45RO+ T cells but is also increased on freshly isolated naive CD45RA+ T cells. In addition, specific CD95-mediated apoptosis is enhanced in both CD4+ and CD8+ T cells. Furthermore, levels of CD95 ligand mRNA are profoundly increased. Specific T-cell receptor/CD3-triggered apoptosis in HIV-1+ children is more enhanced in CD8+ than in CD4+ T cells. Accelerated activation induced cell death of T cells could partially be inhibited by blocking anti-CD95 antibody fragments. These data suggest an involvement of the CD95 receptor/ligand system in T-cell depletion and apoptosis in AIDS and may open new avenues of rational intervention strategies.  相似文献   
648.
Children with neurofibromatosis type 1 (NF1) are at increased risk of developing malignant myeloid disorders, particularly juvenile chronic myelogenous leukemia/juvenile myelomonocytic leukemia (JCML/JMML). We investigated bone marrows from 11 such patients (8 boys and 3 girls) and detected allelic losses at the NF1 locus in 4 of them and probable losses in 2 others. To determine which hematopoietic cell lineages were derived from the abnormal clones, Epstein-Barr virus (EBV)-transformed cell lines and CD34+ cells were analyzed from 3 children with JCML with allelic losses in unfractionated marrow. CD34 cells from these 3 patients lacked the normal NF1 allele, whereas EBV cell lines retained it. Erythroblasts plucked from the burst-forming unit-erythroid colonies of one of these children lacked the normal NF1 allele. We also studied a 10-month-old boy with NF1 who developed an unusual myeloproliferative syndrome. His bone marrow and EBV cell line both showed loss of the normal NF1 allele. In our series and in the literature, male sex and maternal transmission of NF1 were associated with the highest risk of myeloid leukemia. These data (1) provide strong genetic evidence that NF1 functions as a tumor-suppressor in early myelopoiesis, (2) confirm the clonal nature of JCML/JMML, (3) suggest that the elevation in fetal hemoglobin seen in JCML/JMML is a result of primary involvement of erythroid progenitors in the malignant clone, (4) show consistent loss of NF1 in the CD34 cells of affected children and show that the malignant clone may also give rise to pre-B cells in some cases, and (5) implicate epigenetic factors in the development of leukemia in children with NF1.  相似文献   
649.
Growth and development following marrow transplantation for leukemia   总被引:1,自引:3,他引:1  
One hundred forty-two patients between the ages of 1 and 17 years who survived disease-free more than 1 year after marrow transplantation for hematologic malignancy had growth and development evaluations from one to 14 years posttransplant (median 4 years). Prior to transplant all children received multiagent chemotherapy and 55 also received central nervous system irradiation, but none had growth and development evaluations. Marrow transplant preparation included high-dose chemotherapy and total body irradiation (TBI) given as a single dose of 9.2 to 10.0 Gy (79 patients) or as fractionated doses of 2.0 to 2.25 Gy/d for six to seven days (63 patients). After transplant abnormal thyroid function was present in 39%. Stimulated 11-desoxycortisol levels were subnormal in 24% of patients evaluated. Growth hormone (GH) deficiency was present in 17 of 25 children who received previous cranial irradiation. Partial GH deficiency was present in 4 of 25 who received previous cranial irradiation and in 6 of 18 who had not received cranial irradiation. Height velocity was decreased in all patients. After transplant, height was significantly influenced by chronic graft-v-host disease and single-dose TBI. Sixty-eight percent had delayed development of secondary sexual characteristics. Gonadal failure occurred in nearly all who were postpubertal at transplant. While it is not possible to determine how many of these endocrine abnormalities occurred as a result of treatment administered prior to transplantation, these data do demonstrate that children who become long-term survivors after marrow transplantation for hematologic malignancy have endocrine abnormalities that adversely affect growth and development.  相似文献   
650.
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