全文获取类型
收费全文 | 4307篇 |
免费 | 273篇 |
国内免费 | 1篇 |
出版年
2024年 | 6篇 |
2023年 | 37篇 |
2022年 | 111篇 |
2021年 | 160篇 |
2020年 | 122篇 |
2019年 | 156篇 |
2018年 | 212篇 |
2017年 | 165篇 |
2016年 | 221篇 |
2015年 | 275篇 |
2014年 | 283篇 |
2013年 | 367篇 |
2012年 | 413篇 |
2011年 | 367篇 |
2010年 | 219篇 |
2009年 | 169篇 |
2008年 | 221篇 |
2007年 | 192篇 |
2006年 | 155篇 |
2005年 | 148篇 |
2004年 | 138篇 |
2003年 | 100篇 |
2002年 | 92篇 |
2001年 | 25篇 |
2000年 | 24篇 |
1999年 | 25篇 |
1998年 | 22篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 10篇 |
1994年 | 12篇 |
1993年 | 10篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 3篇 |
1989年 | 9篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 9篇 |
1985年 | 6篇 |
1984年 | 5篇 |
1982年 | 4篇 |
1981年 | 5篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1976年 | 5篇 |
1973年 | 6篇 |
1972年 | 4篇 |
1968年 | 4篇 |
1962年 | 2篇 |
排序方式: 共有4581条查询结果,搜索用时 31 毫秒
91.
Santos Brígida Delgadinho Mariana Ferreira Joana Germano Isabel Miranda Armandina Arez Ana Paula Faustino Paula Brito Miguel 《Molecular biology reports》2020,47(7):5397-5402
Molecular Biology Reports - The aim of this study was to explore the association between alpha-thalassemia, fetal hemoglobin, hematological indices, and clinical adverse events in Angolan sickle... 相似文献
92.
de Farias Bianca Xavier Costa Ana Beatriz Engel Nicole Alessandra de Souza Goldim Mariana Pereira da Rosa Turatti Cristini Cargnin-Cavalho Anderson Fortunato Jucélia Jeremias Petronilho Fabricia Jeremias Isabela Casagrande Rezin Gislaine Tezza 《Neurochemical research》2020,45(10):2487-2498
Neurochemical Research - Obesity is characterized by chronic inflammation of low grade. The cholinergic anti-inflammatory pathway favors the reduction of the inflammatory response. In this work the... 相似文献
93.
Ernetti Julia R. Boschetti Joana P. Delazeri Francieli De Bastiani Veluma I. M. Pontes Mariana R. Ribeiro Luisa P. Lingnau Rodrigo Toledo Luís Felipe Lucas Elaine M. 《Hydrobiologia》2020,847(16):3355-3364
Hydrobiologia - Pithecopus rusticus is an endemic amphibian restricted to the type locality, in southern Brazil, and possibly endangered to extinction, due to habitat degradation. However, an... 相似文献
94.
Fabricio de Carvalho Veruska L. F. Alves Walter M. T. Braga Celso V. Xavier Jr. Gisele W. B. Colleoni 《Cancer immunology, immunotherapy : CII》2013,62(1):191-195
The exact function of MAGE-C1/CT7 and MAGE-C2/CT10 is not yet understood in multiple myeloma (MM). However, the homologs MAGE-C1/CT7 and MAGE-C2/CT10 genes encode highly immunogeneic cancer/testis antigens (CTAs) and can be potential targets for T cell-based immunotherapy. MAGE-C1/CT7 and MAGE-C2/CT10 mRNA expression were investigated in MM patients, solitary plasmacytomas, monoclonal gammopathies of undetermined significance (MGUS) and bone marrow (BM) aspirates from healthy donors by RT-PCR. MAGE-C1/CT7 and MAGE-C1/CT10 were expressed in 67 and 59 % of the 46 MM analyzed patients. At least one of the genes was expressed in 76 % of MM cases. Solitary plasmacytoma also showed MAGE-C1/CT7 and MAGE-C2/CT10 expression. MAGE-C1/CT7 and MAGE-C2/CT10 were not expressed in normal BM samples, showing restricted expression of these CTA genes in MM, solitary plasmacytoma and MGUS. In the present study, we found high expression of the homologs MAGE-C1/CT7 and MAGE-C2/CT10 in monoclonal gammopathies and speculate whether these genes might represent a valuable therapeutic option for myeloma, in particular for combined immunotherapy. 相似文献
95.
Christoph Domschke Yingzi Ge Isa Bernhardt Sarah Schott Sophia Keim Simone Juenger Mariana Bucur Luisa Mayer Maria Blumenstein Joachim Rom Joerg Heil Christof Sohn Andreas Schneeweiss Philipp Beckhove Florian Schuetz 《Cancer immunology, immunotherapy : CII》2013,62(6):1053-1060
Background
The bone marrow (BM) of breast cancer patients harbors tumor-reactive memory T cells (TCs) with therapeutic potential. We recently described the immunologic effects of adoptive transfer of ex vivo restimulated tumor-reactive memory TCs from the BM of 12 metastasized breast cancer patients in a clinical phase-I study. In this trial, adoptive T cell transfer resulted in the occurrence of circulating tumor antigen-reactive type-1 TCs. We here describe the long-term clinical outcome and its correlation with tumor-specific cellular immune response in 16 metastasized breast cancer patients, including 12 included in the original study.Methods
Sixteen metastatic breast cancer patients with preexisting tumor-reactive BM memory TCs were included into the study. The study protocol involved one transfusion of TCs which were reactivated in vitro with autologous dendritic cells pulsed with lysates of MCF-7 breast cancer cells as source of tumor antigens. The presence of tumor-reactive memory TCs was analyzed by IFN-γ ELISpot assays.Results
Tumor-reactive memory TCs in the peripheral blood were induced de novo in 7/16 patients (44 %) after adoptive TC transfer. These patients were considered immunologic responders to the therapy. Positive adoptive immunotherapy (ADI) response was observed significantly more often in patients without bone metastases (p = 0.0051), in patients with high levels of tumor-reactive BM TCs prior to therapy (p = 0.036) and correlated significantly with the estimated numbers of transferred tumor-reactive TCs (p = 0.0021). After the treatment, we observed an overall median survival of 33.8 months in the total cohort with three patients alive at last follow-up and more than 7 years after ADI. Numbers of transferred tumor-reactive TCs correlated significantly with the overall survival of patients (p = 0.017). Patients with an immunologic response to ADI in the peripheral blood had a significantly longer median survival than nonresponders (median survival 58.6 vs. 13.6 months; p = 0.009).Conclusion
In metastasized breast cancer patients, adoptive transfer of BM TCs can induce the presence of tumor antigen-reactive type-1 TCs in the peripheral blood. Patients with immunologic response after ADI show a significantly longer overall survival. Patients with bone metastases significantly less frequently respond to the treatment and, therefore, might not be optimal candidates for ADI. Although the present study does not yet prove the therapeutic effect of ADI, these findings shed light on the relation between immune response and cancer prognosis and suggest that transfer of reactivated BM TCs might bear therapeutic potential. 相似文献96.
Eldamária de Vargas Wolfgramm Lyvia Neves Rebello Alves Elaine Stur Thaís Tristão Tovar Mariana Penha De Nadai Sartori Allan Kardec de Castro Neto Iúri Drumond Louro 《Molecular biology reports》2013,40(3):2139-2144
Breast cancer is a heterogeneous disease, previously associated with genomic instability. Our aim was to analyze microsatellite markers in order to determine patterns and levels of instability, as well as possible correlations with histopathological parameters. Polymerase chain reaction was used to characterize microsatellite instability (MSI) and loss of heterozygosity (LOH) in 107 breast carcinomas at twelve microsatellite loci. Some of the markers were selected because of their relation to steroid hormone metabolism, which seems to be related to sporadic breast cancer risk. D5S346 and D17S250 markers showed a statistically significant frequency of MSI. LOH in D3S1611, D17S250, AR and ER-β were associated with some parameters of worse prognosis. Marker group analysis showed that CYP19, AR and ER-β were related to histological grade III, ER-negative and PR-negative cases. Our results suggest that marker group analysis may be preferred to the single marker strategy, being predictive of worst prognosis when single markers are unable to provide such information. A further evaluation of steroid metabolism genes and their association with low penetrance genes in breast cancer may be useful. 相似文献
97.
Aparecida de Lourdes Perim Roberta Losi Guembarovski Julie Massayo Maeda Oda Leandra Fiori Lopes Carolina Batista Ariza Marla Karine Amarante Maria Helena Pelegrinelli Fungaro Karen Brajão de Oliveira Maria Angelica Ehara Watanabe 《Molecular biology reports》2013,40(7):4591-4596
Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy. Genetic polymorphisms in the 3′UTR region of the CXCL12 (rs1801157) and TP53 codon 72 (rs1042522) genes may contribute to susceptibility to childhood ALL because they affect some important processes, such as metastasis regulation and tumor suppression. Thus the objective of the present study was to detect the frequency of two genetic polymorphisms in ALL patients and controls and to add information their impact on genetic susceptibility and prognosis. The CXCL12 and TP53 polymorphisms were tested in 54 ALL child patients and in 58 controls by restriction fragment length polymerase chain reaction and allelic specific chain reaction techniques, respectively. The frequencies of both allelic variants were higher in ALL patients than in the controls and indicated a positive association: OR = 2.44; 95 % CI 1.05–5.64 for CXCL12 and OR = 2.20; 95 % CI 1.03–4.70 for TP53. Furthermore, when the two genetic variants were analyzed together, they increased significantly more than fivefold the risk of this neoplasia development (OR = 5.24; 95 % CI 1.39–19.75), indicating their potential as susceptibility markers for ALL disease and the relevance of the allelic variant combination to increased risk of developing malignant tumors. Future studies may indicate a larger panel of genes involved in susceptibility of childhood ALL and other hematological neoplasias. 相似文献
98.
Rosane Aparecida Ribeiro Sandra Lucinei Balbo Letícia Prates Roma Rafael Ludemann Camargo Luiz Felipe Barella Emerielle Cristine Vanzela Paulo Cesar de Freitas Mathias Everardo Magalhães Carneiro Antonio Carlos Boschero Maria Lúcia Bonfleur 《Molecular biology reports》2013,40(7):4521-4528
Monosodium glutamate-obese rats are glucose intolerant and insulin resistant. Their pancreatic islets secrete more insulin at increasing glucose concentrations, despite the possible imbalance in the autonomic nervous system of these rats. Here, we investigate the involvement of the cholinergic/protein kinase (PK)-C and PKA pathways in MSG β-cell function. Male newborn Wistar rats received a subcutaneous injection of MSG (4 g/kg body weight (BW)) or hyperosmotic saline solution during the first 5 days of life. At 90 days of life, plasma parameters, islet static insulin secretion and protein expression were analyzed. Monosodium glutamate rats presented lower body weight and decreased nasoanal length, but had higher body fat depots, glucose intolerance, hyperinsulinemia and hypertrigliceridemia. Their pancreatic islets secreted more insulin in the presence of increasing glucose concentrations with no modifications in the islet-protein content of the glucose-sensing proteins: the glucose transporter (GLUT)-2 and glycokinase. However, MSG islets presented a lower secretory capacity at 40 mM K+ (P < 0.05). The MSG group also released less insulin in response to 100 μM carbachol, 10 μM forskolin and 1 mM 3-isobutyl-1-methyl-xantine (P < 0.05, P < 0.0001 and P < 0.01). These effects may be associated with a the decrease of 46 % in the acetylcholine muscarinic type 3 (M3) receptor, and a reduction of 64 % in PKCα and 36 % in PKAα protein expressions in MSG islets. Our data suggest that MSG islets, whilst showing a compensatory increase in glucose-induced insulin release, demonstrate decreased islet M3/PKC and adenylate cyclase/PKA activation, possibly predisposing these prediabetic rodents to the early development of β-cell dysfunction. 相似文献
99.
Raquel Schier Guerra Mariana Machado Fidelis do Nascimento Stephanie Miesch Mohammad Javad Najafzadeh Raphael Orélis Ribeiro Antonio Ostrensky Gerrit Sybren de Hoog Vania Aparecida Vicente Walter A. Boeger 《Mycopathologia》2013,175(5-6):421-430
Knowledge of natural ecology is essential for a better understanding of pathogenicity and opportunism in black yeast-like fungi. Although etiological agents of diseases caused by these fungi are supposed to originate from the environment, their isolation from nature is difficult. This is probably due to their oligotrophic nature, low competitive ability, and, overall, insufficient data on their natural habitat. We obtained environmental samples from mangrove areas where mortalities by lethargic crab disease (LCD) are reported and areas without disease recorded. Isolation of chaetothyrialean black yeasts and relatives was performed using a highly selective protocol. Species-specific primers were used to determine if these isolates represented Exophiala cancerae or Fonsecaea brasiliensis, two proven agents of LCD, in order to test hypotheses about the origin of the disease. Isolates, identified by morphology as Fonsecaea- or Exophiala-like, were tested specific diagnostic markers for the fungi associated with LCD. Although several black fungi were isolated, the main causative agent of the LCD, E. cancerae, was not found. Molecular markers for F. brasiliensis revealed 10 positive bands for isolates from biofilms on mangrove leaves, branches, and aerial roots, of which four were confirmed by ITS sequencing. The absence of E. cancerae in environmental samples suggests that the species is dependent on the crab, as a genuine pathogen, different from F. brasiliensis, which is probably not dependent on the host species, U. cordatus. However, we did not attempt isolation from the marine water, which may represent the pathway of dispersion of the black yeast species between neighbor mangroves. 相似文献
100.
Carolina Torres Mariana Mimosa Leonardo Galetto 《Plant Systematics and Evolution》2013,299(8):1433-1441
Plant–pollinator interactions provide highly important ecological functions, and are influenced by floral nectar characteristics. The night blooming Datura ferox is an excellent model to test general hypotheses on the relationship between nectar traits (e.g., nectar secretion patterns, nectar chemical composition), pollinators and reproductive success for invasive, weedy species in highly modified ecosystems as crop fields. We hypothesized an adjustment between nectar composition and secretion dynamics through flower anthesis and the activity and requirements of nocturnal pollinators. Nectar chemical analyses showed low quantities of amino acids and lipids, phenolics, and alkaloids were not detected. D. ferox showed sucrose-dominant nectar with comparable amount of hexoses. Sugar proportions did not vary between populations or during flowering season. Most nectar is secreted before flower opening. Nectar resorption was detected at the end of anthesis. Experimentally drained flowers of both populations increased nectar production up to 50 % in the total amount of sugar per flower compared to control flowers. Nectar standing crop was relatively constant during the flowering season, but differences were detected between populations. Nectar traits of D. ferox would be favoring cross-pollination and maintaining seed production of this weed, since recently open flowers display a higher amount of nectar and they can renew nectar after a pollinator visit or reabsorb it at the end of anthesis. This nectar source may be important for native pollinators considering that human-induced forest fragmentation is related with the impoverishment of native flora from agro-ecosystems. 相似文献