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891.
Hematophagous vectors strictly require ingesting blood from their hosts to complete their life cycles. Exposure of the alimentary canal of these vectors to the host immune effectors necessitates efficient counteractive measures by hematophagous vectors. The Anopheles mosquito transmitting the malaria parasite is an example of hematophagous vectors that within seconds can ingest human blood double its weight. The innate immune defense mechanisms, like the complement system, in the human blood should thereby immediately react against foreign cells in the mosquito midgut. A prerequisite for complement activation is that the target cells lack complement regulators on their surfaces. In this work, we analyzed whether human complement is active in the mosquito midgut, and how the mosquito midgut cells protect themselves against complement attack. We found that complement remained active for a considerable time and was able to kill microbes within the mosquito midgut. However, the Anopheles mosquito midgut cells were not injured. These cells were found to protect themselves by capturing factor H, the main soluble inhibitor of the alternative complement pathway. Factor H inhibited complement on the midgut cells by promoting inactivation of C3b to iC3b and preventing the activity of the alternative pathway amplification C3 convertase enzyme. An interference of the FH regulatory activity by monoclonal antibodies, carried to the midgut via blood, resulted in increased mosquito mortality and reduced fecundity. By using a ligand blotting assay, a putative mosquito midgut FH receptor could be detected. Thereby, we have identified a novel mechanism whereby mosquitoes can tolerate human blood. 相似文献
892.
Marta Winiecka-Klimek Maciej Smolarz Maciej P. Walczak Jolanta Zieba Krystyna Hulas-Bigoszewska Blazej Kmieciak Sylwester Piaskowski Piotr Rieske Dawid P. Grzela Ewelina Stoczynska-Fidelus 《PloS one》2015,10(11)
Tumorigenic potential of induced pluripotent stem cells (iPSCs) infiltrating population of induced neural stem cells (iNSCs) generated from iPSCs may limit their medical applications. To overcome such a difficulty, direct reprogramming of adult somatic cells into iNSCs was proposed. The aim of this study was the systematic comparison of induced neural cells (iNc) obtained with different methods—direct reprogramming of human adult fibroblasts with either SOX2 (SiNSc-like) or SOX2 and c-MYC (SMiNSc-like) and induced pluripotent stem cells differentiation to ebiNSc—in terms of gene expression profile, differentiation potential as well as proliferation properties. Immunocytochemistry and real-time PCR analyses were used to evaluate gene expression profile and differentiation potential of various iNc types. Bromodeoxyuridine (BrdU) incorporation and senescence-associated beta-galactosidase (SA-β-gal) assays were used to estimate proliferation potential. All three types of iNc were capable of neuronal differentiation; however, astrocytic differentiation was possible only in case of ebiNSc. Contrary to ebiNSc generation, the direct reprogramming was rarely a propitious process, despite 100% transduction efficiency. The potency of direct iNSCs-like cells generation was lower as compared to iNSCs obtained by iPSCs differentiation, and only slightly improved when c-MYC was added. Directly reprogrammed iNSCs-like cells were lacking the ability to differentiate into astrocytic cells and characterized by poor efficiency of neuronal cells formation. Such features indicated that these cells could not be fully reprogrammed, as confirmed mainly with senescence detection. Importantly, SiNSc-like and SMiNSc-like cells were unable to achieve the long-term survival and became senescent, which limits their possible therapeutic applicability. Our results suggest that iNSCs-like cells, generated in the direct reprogramming attempts, were either not fully reprogrammed or reprogrammed only into neuronal progenitors, mainly because of the inaccuracies of currently available protocols. 相似文献
893.
Florence Cliquet Evelyne Picard-Meyer Miroslav Mojzis Zuzana Dirbakova Zita Muizniece Ingrida Jaceviciene Franco Mutinelli Marta Matulova Jitka Frolichova Ivan Rychlik Vladimir Celer 《PloS one》2015,10(10)
Although rabies incidence has fallen sharply over the past decades in Europe, the disease is still present in Eastern Europe. Oral rabies immunization of wild animal rabies has been shown to be the most effective method for the control and elimination of rabies. All rabies vaccines used in Europe are modified live virus vaccines based on the Street Alabama Dufferin (SAD) strain isolated from a naturally-infected dog in 1935. Because of the potential safety risk of a live virus which could revert to virulence, the genetic composition of three commercial attenuated live rabies vaccines was investigated in two independent laboratories using next genome sequencing. This study is the first one reporting on the diversity of variants in oral rabies vaccines as well as the presence of a mix of at least two different variants in all tested batches. The results demonstrate the need for vaccine producers to use new robust methodologies in the context of their routine vaccine quality controls prior to market release. 相似文献
894.
Peter Valkovic Michal Minar Helena Singliarova Jan Harsany Marta Hanakova Jana Martinkova Jan Benetin 《PloS one》2015,10(8)
Pain is an important and distressing symptom in Parkinson’s disease (PD). Our aim was to determine the prevalence of pain, its various types and characteristics, as well as its impact on depression and quality of life (QoL) in patients with PD. How pain differs in early- and advanced-stage PD and male and female PD patients was of special interest. One hundred PD patients on dopaminergic medications had a neurological examination and participated in a structured interview on pain characteristics and completed standardized questionnaires. A total of 76% of the patients had pain. The following types of pain were present: musculoskeletal pain accounted for 41% of the total pain, dystonic pain for 17%, central neuropathic pain for 22%, radicular pain for 27%, and other pains (non-radicular low back pain, arthritic, and visceral pain) made up 24%. One type of pain affected 29% of all the subjects, two types 35%, three types 10%, and four types of pain were reported by 2%. All types of pain were more prevalent in advanced-stage PD subjects than in early-stage PD subjects, except for arthritic pain (subclassified under”other pain”). The frequency and intensity of actual, average, and worst experienced pain were significantly more severe in advanced-stage subjects. PD subjects with general pain and in advanced stages were more depressed and had poorer QoL. Depression correlated with worst pain in the last 24 hours and with pain periodicity (the worst depression score in patients with constant pain). QoL correlated with average pain in the last 7 days. Pain is a frequent problem in PD patients, and it worsens during the course of the disease. 相似文献
895.
Cristina Escoda-Ferran Esther Carrasco Miguel Caballero-Baños Cristina Miró-Julià Mario Martínez-Florensa Marta Consuegra-Fernández Vanesa G. Martínez Fu-Tong Liu Francisco Lozano 《FEBS letters》2014
CD6 is a lymphocyte glycoprotein receptor that physically associates with the antigen-specific receptor complex at the center of the immunological synapse, where it interacts with its ligand CD166/ALCAM. The present work reports the carbohydrate-dependent interaction of CD6 and CD166/ALCAM with Galectin-1 and -3, two well-known soluble mammalian lectins. Both galectins interfered with superantigen-induced T cell proliferation and cell adhesion phenomena mediated by the CD6-CD166/ALCAM pair, while CD6 expression protected cells from galectin-induced apoptosis. The results suggest that interaction of Galectin-1 and -3 with CD6 and CD166/ALCAM might modulate some relevant aspects of T cell physiology. 相似文献
896.
Brucella abortus is the etiological agent of bovine brucellosis, an infectious disease of humans and cattle. Its pathogenesis is mainly based
on its ability to survive and multiply inside macrophages. It has been demonstrated that if B. abortus ferrochelatase cannot incorporate iron into protoporphyrin IX to synthesize heme, the intracellular replication and virulence
in mice is highly attenuated. Therefore, it can be hypothesized that the unavailability of iron could lead to the same attenuation
in B. abortus pathogenicity. Thus, the purpose of this work was to obtain a B. abortus derivative unable to keep an internal iron pool and test its ability to replicate under iron limitation. To achieve this,
we searched for iron-storage proteins in the genome of brucellae and found bacterioferritin (Bfr) as the sole ferritin encoded.
Then, a B. abortus bfr mutant was built up and its capacity to store iron and replicate under iron limitation was investigated. Results indicated
that B. abortus Bfr accounts for 70% of the intracellular iron content. Under iron limitation, the bfr mutant suffered from enhanced iron restriction with respect to wild type according to its growth retardation pattern, enhanced
sensitivity to oxidative stress, accelerated production of siderophores, and altered expression of membrane proteins. Nonetheless,
the bfr mutant was able to adapt and replicate even inside eukaryotic cells, indicating that B. abortus responds to internal iron starvation before sensing external iron availability. This suggests an active role of Bfr in controlling
iron homeostasis through the availability of Bfr-bound iron. 相似文献
897.
898.
Host range, prevalence, and infection intensity of Paranosema locustae in grasshoppers at an establishment site in Patagonia, Argentina, were recorded. Results agreed with earlier observations at other introduction-establishment areas. Affected grasshoppers were melanoplines (Baeacris punctulatus, Dichroplus elongatus, Dichroplus maculipennis). Sporulation was not observed in instars I, II, and III. 相似文献
899.
Elíades Lorena Cabello Marta Voget Claudio Galarza Betina Saparrat Mario 《World journal of microbiology & biotechnology》2010,26(11):2105-2111
A screening was carried out on 69 fungal strains isolated from alkaline-calcareous, neutral and alkaline-sodic soils, as well
as from their associated plant material, to determine their ability to grow at alkaline pH. A total of 32 fungi were selected
for their ability to produce alkaline keratinase activity in submerged shaken cultures supplemented with soybean meal (SM)
and tryptone and on cow hair (CH) under solid state fermentation conditions. Although several fungal strains produced keratinolytic
activity on both SM and CH, they differed in the levels detected. Among them, Aspergillus niger, Cladosporium cladosporioides, Metarrhizium anisopliae, Neurospora tetrasperma and Westerdikella dispersa were the best producers, with levels higher than 1.2 U ml−1. Different fungal species are here reported for the first time for their ability to produce keratinolytic activity at alkaline
pH. 相似文献
900.
Marta Concheiro Hendreé Jones Rolley E. Johnson Diaa M. Shakleya Marilyn A. Huestis 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(1):13-20
An LCMSMS method was developed and fully validated for the simultaneous quantification of buprenorphine (BUP), norbuprenorphine (NBUP), buprenorphine-glucuronide (BUP-Gluc), and norbuprenorphine-glucuronide (NBUP-Gluc) in 0.5 mL plasma, fulfilling confirmation criteria with two transitions for each compound with acceptable relative ion intensities. Transitions monitored were 468.3 > 396.2 and 468.3 > 414.3 for BUP, 414.3 > 340.1 and 414.3 > 326.0 for NBUP, 644.3 > 468.1 and 644.3 > 396.3 for BUP-Gluc, and 590.3 > 414.3 and 590.3 > 396.2 for NBUP-Gluc. Linearity was 0.1–50 ng/mL for BUP and BUP-Gluc, and 0.5–50 ng/mL for NBUP and NBUP-Gluc. Intra-day, inter-day, and total assay imprecision (%RSD) were <16.8%, and analytical recoveries were 88.6–108.7%. Extraction efficiencies ranged from 71.1 to 87.1%, and process efficiencies 48.7 to 127.7%. All compounds showed ion enhancement, except BUP-Gluc that demonstrated ion suppression: variation between 10 different blank plasma specimens was <9.1%. In six umbilical cord plasma specimens from opioid-dependent pregnant women receiving 14–24 mg/day BUP, NBUP-Gluc was the predominant metabolite (29.8 ± 7.6 ng/mL), with BUP-Gluc (4.6 ± 4.8 ng/mL), NBUP (1.5 ± 0.8 ng/mL) and BUP (0.4 ± 0.2 ng/mL). Although BUP biomarkers can be quantified in umbilical cord plasma in low ng/mL concentrations, the significance of these data as predictors of neonatal outcomes is currently unknown. 相似文献