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The Vietnam Initiative on Zoonotic Infections (VIZIONS): A Strategic Approach to Studying Emerging Zoonotic Infectious Diseases 总被引:1,自引:0,他引:1
Maia A. Rabaa Ngo Tri Tue Tran My Phuc Juan Carrique-Mas Karen Saylors Matthew Cotten Juliet E. Bryant Ho Dang Trung Nghia Nguyen Van Cuong Hong Anh Pham Alessandra Berto Voong Vinh Phat Tran Thi Ngoc Dung Long Hoang Bao Ngo Thi Hoa Heiman Wertheim Behzad Nadjm Corina Monagin H. Rogier van Doorn Motiur Rahman My Phan Vu Tra James I. Campbell Maciej F. Boni Pham Thi Thanh Tam Lia van der Hoek Peter Simmonds Andrew Rambaut Tran Khanh Toan Nguyen Van Vinh Chau Tran Tinh Hien Nathan Wolfe Jeremy J. Farrar Guy Thwaites Paul Kellam Mark E. J. Woolhouse Stephen Baker 《EcoHealth》2015,12(4):726-735
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The type II transmembrane protease TMPRSS2 activates the spike (S) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) on the cell surface following receptor binding during viral entry into cells. In the absence of TMPRSS2, SARS-CoV achieves cell entry via an endosomal pathway in which cathepsin L may play an important role, i.e., the activation of spike protein fusogenicity. This study shows that a commercial serine protease inhibitor (camostat) partially blocked infection by SARS-CoV and human coronavirus NL63 (HCoV-NL63) in HeLa cells expressing the receptor angiotensin-converting enzyme 2 (ACE2) and TMPRSS2. Simultaneous treatment of the cells with camostat and EST [(23,25)trans-epoxysuccinyl-L-leucylamindo-3-methylbutane ethyl ester], a cathepsin inhibitor, efficiently prevented both cell entry and the multistep growth of SARS-CoV in human Calu-3 airway epithelial cells. This efficient inhibition could be attributed to the dual blockade of entry from the cell surface and through the endosomal pathway. These observations suggest camostat as a candidate antiviral drug to prevent or depress TMPRSS2-dependent infection by SARS-CoV. 相似文献
115.
A.-M. N’goan-Domoua N. Kouamé A. Kouamé-Koutouan S. Anet-Koua W.-A. Lia R.-D. N’gbesso A.-K. Kéita 《Médecine Nucléaire》2012,36(10):615-618
ObjectiveTo demonstrate the role of obstetric Doppler ultrasound in reducing the rate of maternal-fetal complications in childbirth.Patients and methodsCase-control study lasting 12 months carried out at the regional hospital center in Yamoussoukro (Ivory Coast). It involved 204 parturients who had a “complicated delivery”. We have divided them into two groups with one group of cases, consisting of 151 parturients who did not have obstetric ultrasound and a group of controls, consisting of 53 parturients who had an obstetric ultrasound during labor. We studied the occurrence of maternal and neonatal complications in the two groups.ResultsDuring the study period, 1182 vaginal deliveries were made. Of these, 204 were complicated (17.3%). Three maternal deaths and 12 cases of uterine rupture were observed in the case group against none maternal complication in the control group. Thirty-eight cases of stillbirth against zero in controls, 69 cases of neonatal brain injury cases against three among controls were evidenced. The causes of complications were dominated by the obstruction (21 cases) followed by abruptio placentae (eight cases) in the mother. Fetal distress (69 cases) followed by the circular of umbilical cord (48 cases) was the dominant causes in fetus.ConclusionComplicated deliveries represent over a quarter of births in Ivory Coast. Most complications can be avoided by an ultrasound exploration of all new mothers in the labor ward. 相似文献
116.
Notch, epidermal growth factor receptor, and beta1-integrin pathways are coordinated in neural stem cells 总被引:4,自引:0,他引:4
Notch1 and beta1-integrins are cell surface receptors involved in the recognition of the niche that surrounds stem cells through cell-cell and cell-extracellular matrix interactions, respectively. Notch1 is also involved in the control of cell fate choices in the developing central nervous system (Lewis, J. (1998) Semin. Cell Dev. Biol. 9, 583-589). Here we report that Notch and beta1-integrins are co-expressed and that these proteins cooperate with the epidermal growth factor receptor in neural progenitors. We describe data that suggests that beta1-integrins may affect Notch signaling through 1) physical interaction (sequestration) of the Notch intracellular domain fragment by the cytoplasmic tail of the beta1-integrin and 2) affecting trafficking of the Notch intracellular domain via caveolin-mediated mechanisms. Our findings suggest that caveolin 1-containing lipid rafts play a role in the coordination and coupling of beta1-integrin, Notch1, and tyrosine kinase receptor signaling pathways. We speculate that this will require the presence of the adequate beta1-activating extracellular matrix or growth factors in restricted regions of the central nervous system and namely in neurogenic niches. 相似文献
117.
Metabolic response to exogenous ethanol in yeast: an in vivo NMR and mathematical modelling approach
Martini S Ricci M Bartolini F Bonechi C Braconi D Millucci L Santucci A Rossi C 《Biophysical chemistry》2006,120(2):135-142
The understanding of the metabolic behaviour of complex systems such as eukaryotic cells needs the development of new approaches that are able to deal with the complexity due to a large number of interactions within the system. In this paper, we applied an approach based on the combined use of in vivo NMR experiments and mathematical modelling in order to analyze the metabolic response to ethanol stress in a wild-strain of Saccharomyces cerevisiae. Considering the cellular metabolic processes resulting from activation, inhibition, and feed-back activities, we developed a model able to describe the modulation of the whole system induced by an external stress due to increasing concentrations of exogenous ethanol. This approach was able to interpret the experimental results in terms of metabolic response to exogenous ethanol in the yeast. The robustness and flexibility of the model enables it to work correctly at different initial exogenous ethanol concentrations. 相似文献
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119.
The House Sparrow (Passer domesticus), formerly a common bird species, has shown a rapid decline in Western Europe over recent decades. In The Netherlands, its
decline is apparent from 1990 onwards. Many causes for this decline have been suggested that all decrease the vital rates,
i.e. survival and reproduction, but their actual impact remains unknown. Although the House Sparrow has been dominant in The
Netherlands, data on life history characteristics for this bird species are scarce: data on reproduction are non-existent,
and here we first present survival estimates based on live encounters and dead recoveries of marked individuals over the period
1976–2003, 14 years before and 14 years during the decline, reported to the Dutch Ringing Centre. We show that there is an
indication that both juvenile and adult survival are lower during the period of decline.
Secondly, to be able to analyse the relative impact of changes in the vital rates, we formulated a general matrix model based
on a range of survival values between zero and one with a step size of 0.01 (both juvenile and adult yearly survival) and
a range of realistic reproduction values (one, three or five fledglings per pair per year). With the matrix model, we calculated
the finite rate of population change (λ) and applied elasticity analysis. To diagnose the cause of the decline in the Dutch
House Sparrow, we parameterised the model with estimates of survival values before and during the decline and present the
resulting λ. With the survival estimates from the declining period, λ < 1 only if reproduction is relatively low. We discuss this result within the light of available literature data on survival
in the House Sparrow. Finally, we evaluate which of the suggested causes of population decline should be reversed to mitigate
the decline and how this can be achieved. 相似文献
120.
Ferreira Júnior JR Ramos AS Chambergo FS Stambuk BU Muschellack LK Schumacher R El-Dorry H 《Biochemical and biophysical research communications》2006,339(1):30-36
Genes for the enzymes that metabolize galactose in Saccharomyces cerevisiae are strongly induced by galactose and tightly repressed by glucose. Because glucose also represses mitochondrial activity, we examined if derepression of the GAL1 galactokinase gene requires physiologically active mitochondria. The effect of mitochondria on the expression of GAL1 was analyzed by a novel approach in which the activity of the organelles was altered by functional expression of URF13, a mitochondrial protein unique to the Texas-type cytoplasmic male sterility phenotype in maize. Mitochondrial targeting and functional expression of the URF13 protein in yeast result in a decrease of the mitochondrial membrane potential similar to those observed in cells treated with mitochondrial inhibitors such as antimycin A or sodium azide. Activation of URF13 in galactose-induced cells results in the inhibition of GAL1 expression in the absence of repressing concentrations of glucose. Our data reveal the existence of a regulatory pathway that connects the derepression of the GAL1 gene with mitochondrial activity. 相似文献