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排序方式: 共有2240条查询结果,搜索用时 15 毫秒
31.
Eliane Gouvêa de Oliveira Barros Antonio Palumbo Jr. Pedro Lucas Prado Mello Rômulo Medina de Mattos Julianna Henriques da Silva Bruno Pontes Nathan Bessa Viana Rackele Ferreira do Amaral Flavia Regina Souza Lima Nathalia Meireles da Costa Celia Yelimar Palmero Leandro Miranda-Alves Christina Maeda Takiya Luiz Eurico Nasciutti 《Clinical & experimental metastasis》2014,31(4):461-474
Tumor establishment, growth, and survival are supported by interactions with microenvironment components. Here, we investigated whether the interactions between prostate cancer cells and cortical astrocytes are associated to a potential role for astrocytes in tumor establishment. We demonstrate that astrocytes interact in vitro with prostatic cancers cells derived from different metastatic sites. Astrocytes and their secreted extracellular matrix, stimulate DU145 cell (a brain-derived prostate tumor cell line) proliferation while inhibiting cell death and modulating the expression of several genes related to prostate cancer progression, suggesting the activation of EMT process in these cells. In contrast, DU145 cells and their conditioned medium inhibited cell proliferation and induced cell death of astrocytes. On the other hand, the astrocytes were unable to significantly induce an increment of LNCaP cell (a lymph node-derived prostate tumor cell line) proliferative activity. In addition, LNCaP cells were also unable to induce cell death of astrocytes. Thus, we believe that DU145 cells, but not LNCaP cells, present an even more aggressive behavior when interacting with astrocytes. These results provide an important contribution to the elucidation of the cellular mechanisms involved in the brain microenvironment colonization. 相似文献
32.
Results of unrelated cord blood transplant in fanconi anemia patients: risk factor analysis for engraftment and survival. 总被引:2,自引:0,他引:2
Eliane Gluckman Vanderson Rocha Irina Ionescu Marc Bierings Richard E Harris John Wagner Joanne Kurtzberg Martin A Champagne Carmem Bonfim Marco Bittencourt Philip Darbyshire Manuél-Nicolas Fernandez Franco Locatelli Ricardo Pasquini 《Biology of blood and marrow transplantation》2007,13(9):1073-1082
We retrospectively analyzed results of unrelated cord blood transplantation (UCBT) in 93 Fanconi anemia (FA) patients. Median age at transplantation was 8.6 years (1-45). The units transplanted were HLA-A, -B, or -DRB1 identical in 12 cases, 1 HLA mismatch in 35 cases, and 2 or 3 HLA differences in 45 cases. The median number of nucleated cells (NC) and CD34+ cells infused of recipient weight was 4.9x10(7)/kg and 1.9x10(5)/kg, respectively. Participating centers selected the preparative regimen of their choice, in 57 patients (61%), it included Fludarabine. Graft-versus-host disease (GVHD) prophylaxis consisted mostly of cyclosporine with prednisone. Cumulative incidence (CI) of neutrophil recovery was 60+/-5% at day +60. In multivariate analysis, Fludarabine containing regimen and NC infused>or=4.9x10(7)/kg were associated with higher probability of recovery. CI of grade II-IV acute and of chronic GVHD (aGVHD, cGVHD) was 32%+/-5% and 16%+/-4%, respectively. Overall survival (OS) was 40%+/-5%. In multivariate analysis, factors associated with favorable outcome were use of Fludarabine in the conditioning regimen, number of NC infused>or=4.9x10(7)/kg, and negative cytomegalovirus (CMV) serology in the recipient. In conclusion, factors easily modifiable such as donor selection and a Fludarabine-containing regimen can considerably improve survival in FA patients given a UCBT. These data are the basis for designing prospective protocols. 相似文献
33.
Wrobel L Schorscher-Petcu A Dupré A Yoshida M Nishimori K Tribollet E 《Neuroscience letters》2011,488(1):49-54
Nurr1 is a member of the nuclear receptor superfamily and is a regulatory factor of differentiation, migration and maturation of mesencephalic dopaminergic neurons. The present study was designed to observe the dynamic changes in the protein expression of Nurr1 and the relationship between Nurr1 and proliferating cell nuclear antigen (PCNA) during rat brain and spinal cord development. And we also investigated the significance of Nurr1 in differentiation and migration of nerve cells. Paraffin-embedded sections, immunohistochemistry, immunohistochemical double staining and Western blot techniques were used. The results demonstrate that the presence of Nurr1-positive cells increased during embryo development and that these cells slowly migrated to locations far from the lateral ventricle. In postnatal rats, the presence of Nurr1-positive cells surrounding the lateral ventricle decreased markedly. The expression of Nurr1 in the cerebral cortex peaked at postnatal days 1-5 (P1-P5) and then decreased as the cells matured, becoming rare in the mature cerebral cortex. As the cells matured, a staircase-shaped migration of Nurr1-positive cells from dorsal areas to ventral areas of the spinal cord could be observed. As maturation continued, the presence of Nurr1-positive cells in the spinal cord decreased, and no Nurr1-positive cells were found in the mature spinal cord. The comparative observation of Nurr1 and PCNA showed that the two proteins were expressed in different regions and in different cells. Nurr1 was confined to differentiated and migrating immature cells and was not present in proliferating cells. We suggest that Nurr1 may play a regulatory role in the differentiation, migration and maturation of nerve cells in the rat brain and spinal cord. 相似文献
34.
Silvane Braga Santos Paulo Oliveira Tania Luna Anselmo Souza Márcia Nascimento Isadora Siqueira Davi Tanajura André Luiz Muniz Marshall J. Glesby Edgar M. Carvalho 《Journal of medical virology》2012,84(11):1809-1817
The majority of patients infected with human T‐cell lymphotropic virus‐type 1 (HTLV‐1) are considered carriers, but a high frequency of urinary symptoms of overactive bladder, common in HTLV‐1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) have been documented in these patients. The aim of this study was to determine if immunological and viral factors that are seen in HAM/TSP are also observed in these patients. Participants were classified as HTLV‐1 carriers (n = 45), HTLV‐1 patients suffering from overactive bladder (n = 45) and HAM/TSP (n = 45). Cells from HTLV‐1 overactive bladder patients produced spontaneously more proinflammatory cytokines than carriers. TNF‐α and IL‐17 levels were similar in HAM/TSP and HTLV‐1 overactive bladder patients. High proviral load was found in patients with overactive bladder and HAM/TSP and correlated with proinflammatory cytokines. In contrast with findings in patients with HAM/TSP, serum levels of Th1 chemokines were similar in HTLV‐1 overactive bladder and carriers. Exogenous addition of regulatory cytokines decreased spontaneous IFN‐γ production in cell cultures from HTLV‐1 overactive bladder patients. The results show that HTLV‐1 overactive bladder and HAM/TSP patients have in common some immunological features as well as similar proviral load profile. The data show that HTLV‐1 overactive bladder patients are still able to down regulate their inflammatory immune response. In addition, these patients express levels of chemokines similar to carriers, which may explain why they have yet to develop the same degree of spinal cord damage as seen in patients with HAM/TSP. These patients present symptoms of overactive bladder, which may be an early sign of HAM/TSP. J. Med. Virol. 84:1809–1817, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
35.
Priscila Vianna Gabriela Kniphoff Da Silva Bruno Paiva Dos Santos Moisés Evandro Bauer Caroline Abrão Dalmáz Eliane Bandinelli José Artur Bogo Chies 《American journal of reproductive immunology (New York, N.Y. : 1989)》2010,64(5):359-374
Citation Vianna P, da Silva GK, dos Santos BP, Bauer ME, Dalmáz CA, Bandinelli E, Chies JAB. Association between Mannose‐Binding Lectin gene polymorphisms and pre‐eclampsia in Brazilian Women. Am J Reprod Immunol 2010 Problem Mannose‐binding lectin (MBL) is involved in the maintenance of an inflammatory environment in uterus. High MBL levels have been associated with successful pregnancies whereas low levels are involved in pre‐eclampsia (PE) development. Here, we evaluated MBL2 gene polymorphisms in the structural and promoter regions addressing their association with PE. Method of study DNA samples from 162 control pregnant women and 157 pregnant PE women were genotyped and data compared with demographic and clinical characteristics. Results High frequency of C and D alleles (related to low MBL levels) was observed in PE women when compared to controls (C: 0.08 versus 0.03, P = 0.006; D: 0.10 versus 0.05, P = 0.009). Grouping the MBL genotypes according to phenotype, a higher frequency of OO genotype was observed in PE women when compared to control women (0.15 versus 0.04, P = 0.007). Conclusion Our data suggest that women with genotypes associated with low MBL levels could be potential PE developers. 相似文献
36.
Silva ML Ornellas de Souza MH Ribeiro RC Land MG Boulhosa de Azevedo AM Vasconcelos F Otero L Vasconcelos Z Bouzas LF Abdelhay E 《Cancer Genetics and Cytogenetics》2002,137(2):85-90
We report the cytogenetic analysis of newly diagnosed Brazilian children with acute lymphocytic leukemia (ALL). We investigated 100 ALL cases from four different institutions in Rio de Janeiro. The frequency of chromosomal abnormalities was 92.3%. The karyotype profile and recurrent abnormalities found in this study do not differ essentially from those described by other groups. Although the Brazilian population is usually the product of different ethnic groups, our results show that the frequency of each recurrent abnormality is similar to that found in populations without our degree of diverse ethnic composition. Hence, our results suggest that childhood ALL in Brazil has the same biological features as that in developed countries, supporting the use of similar treatment protocols. We can therefore expect to reach the same survival rates in the coming years, depending possibly on the efficacy of the support therapy and extent of social assistance. 相似文献
37.
Retinoic acid and insect juvenile hormone (JH) are structurally related terpenoids which are widespread in nature and are involved in many biological events such as morphogenesis, embryogenesis and cellular differentiation. Here, we investigated the effects of the retinoids 9-cis retinoic acid (9cisRA), all trans retinol (atROH), all trans retinoic acid (atRA) and the juvenoids methoprene (Met) and JH injection on moult and on phenoloxidase activity in the blood-sucking insect Rhodnius prolixus. Overall, we observed that injection of retinoids or juvenoids (120 pmols) in the hemocoel of 4th instar nymphs reduced the percentage of insects which appeared normal in morphology upon moult. Noteworthy, insects exposed to 9cisRA or JH underwent profound morphological changes upon moult, generating abnormal 5th instar nymphs and also markedly increased the death of insects during the moulting process. In addition, reduction in the percentage of insects that moult without any morphological alteration, induced by retinoids or juvenoids treatment, was negatively correlated with insects that both display abnormal moult and those that die during moult. Hemolymphatic phenoloxidase activity in adult male insects injected with 9cisRA, Met and JH were significantly reduced after a bacterial challenge. Together, these results indicate that not only juvenoids but also retinoids play an important role on morphogenesis and on immune response in R. prolixus, suggesting that the molecular mechanisms involved in these events recognize the terpenoid backbone as an important structural determinant in insects. 相似文献
38.
The influence of glucocorticoid receptor single nucleotide polymorphisms on outcome after haematopoietic stem cell transplantation 下载免费PDF全文
Jean Norden Kim F. Pearce Julie A. E. Irving Matthew P. Collin Xiao N. Wang Daniel Wolff Hans‐Jochem Kolb Gerard Socie Zoya Kuzmina Hildegard Greinix Ernst Holler Vanderson Rocha Eliane Gluckman Ilona Hromadnikova Anne M. Dickinson 《International journal of immunogenetics》2018,45(5):247-256
Haematopoietic stem cell transplantation (HSCT) remains the only cure for most haematological malignancies, however, the mortality rate remains high. Complications after HSCT include relapse, graft versus host disease (GvHD), graft rejection and infection. Over the last few years several groups, have demonstrated that non‐HLA gene polymorphisms can be predictive of outcome after HSCT. Since the glucocorticoid cortisol is pivotal in the regulation of the immune system, we decided to examine single nucleotide polymorphisms (SNPs; rs6198, rs33388 and rs33389) within the glucocorticoid receptor (GR) and correlate with HSCT outcome. The training set consisted of patients (n = 458) who underwent HSCT for acute leukaemia between 1983 and 2005. In the recipients, the absence of the ACT haplotype and absence of the T allele of rs33388 were associated with decreased OS and the absence of the ACT haplotype, the absence of the T allele of rs33388 and the presence of the ATA haplotype were associated with increased risk of relapse. In addition, the presence of the ACT haplotype in the recipient showed a trend to be associated with increased risk of chronic graft versus host disease (cGvHD). The patients in this cohort received mainly myeloablative conditioning (n = 327). The SNPs in the glucocorticoid receptor were then investigated in a validation set (n = 251) of HSCT patients transplanted for acute leukaemia from 2006. This cohort contained significantly more patients that had received reduced intensity conditioning (RIC). Some of the results could be validated in these patients. However, contrary to the training set, the absence of the haplotype ACT in the donor in this cohort was associated with increased risk of cGvHD. Differences in the conditioning were shown to influence the results. These results are the first to associate GR SNPs with HSCT outcome and demonstrate the inherent problems of replicating SNP association studies in HSCT, due to different pre‐transplant regimens. 相似文献
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