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171.
Erika V. S. Albuquerque Welcimar G. Cunha Aulus E. A. D. Barbosa Poliene M. Costa João B. Teixeira Giovanni R. Vianna Glaucia B. Cabral Diana Fernandez Maria F. Grossi-de-Sa 《In vitro cellular & developmental biology. Plant》2009,45(5):532-539
The genetic modification of Coffea arabica fruits is an important tool for the investigation of physiological characteristics and functional validation of genes related
to coffee bean quality traits. In this work, plants of C. arabica cultivar Catuaí Vermelho were successfully genetically modified by bombardment of embryogenic calli. Calli were obtained
from 90% of the leaf explants cultivated in a callogenesis-inducing medium modified with 20 μM 2,4-dichlorophenoxyacetic acid
(2,4-D). The resulting calli were bombarded with the pBI426 vector containing a uidA and nptII gene fusion that was driven by the double CaMV35s promoter. Kanamycin-selected embryos were positive for β-glucuronidase
(GUS) activity in histochemical assays and for target gene amplification by polymerase chain reaction. Integration of the
nptII gene was confirmed by Southern blot and showed a low copy number (one to three) of insertions. Transformed plants showed
normal development and settled fruits. GUS expression was assessed in the flower and fruit organs demonstrating the capacity
of the double CaMV35s promoter to drive long-term stable expression of uidA in C. arabica fruit tissues. Moreover, we obtained a T1 progeny presenting 3:1 Mendelian segregation of the uidA gene. This investigation is the first to report exogenous gene expression in coffee fruits and transgenic inheritance in
C. arabica plants. 相似文献
172.
Anelise S. Todeschin Maria Helena Vianna Jacob Silvana Jacobs Maria Flavia Marques Ribeiro Aldo Bolten Lucion 《Hormones and behavior》2009,56(1):93-325
Early-life environmental events can induce profound long-lasting changes in several behavioral and neuroendocrine systems. The neonatal handling procedure, which involves repeated brief maternal separations followed by experimental manipulations, reduces stress responses and sexual behavior in adult rats. The purpose of this study was to analyze the effects of neonatal handling on social behaviors of male and female rats in adulthood, as manifest by the results of social memory and social interaction tests. The number of oxytocin (OT) and vasopressin (VP) neurons in the paraventricular (PVN) and supraoptic (SON) nuclei of hypothalamus were also analyzed. The results did not demonstrate impairment of social memory. Notwithstanding, handling did reduce social investigative interaction and increase aggressive behavior in males, but did not do so in females. Furthermore, in both males and females, handling was linked with reduced number of OT-neurons in the parvocellular region of the PVN, while no differences were detected in the magnocellular PVN or the SON. On the other hand, handled males exhibited increased number of VP-neurons in the magnocellular zone of the PVN. We may conclude that the repeated brief maternal separations can reduce affiliative social behavior in adult male rats. Moreover, the disruption of the mother-infant relationship caused by the handling procedure induced long-lasting morphological changes in critical neuroendocrine areas that are involved in social bonding in mammals. 相似文献
173.
174.
Wanessa LF Tavares Gleidice E Lavalle Mariana S Figueiredo Aline G Souza Angelica C Bertagnolli Fernando AB Viana Paulo RO Paes Rubens A Carneiro Guilherme AO Cavalcanti Marilia M Melo Geovanni D Cassali 《Acta veterinaria Scandinavica》2010,52(1):1-6
Background
Hypertension and proteinuria are medical complications associated with the multisystemic effects of long-term hypercortisolism in dogs with hyperadrenocorticism (HAC).Methods
This study investigated the relationships among adrenocorticotropic hormone (ACTH)-stimulation test results, systemic blood pressure, and microalbuminuria in clinically-healthy dogs (n = 100), in dogs affected with naturally occurring pituitary-dependent (PDH; n = 40), or adrenal-dependent hyperadrenocorticism (ADH; n = 30).Results
Mean systemic blood pressure was similar between clinically healthy dogs and dogs with HAC (p = 0.803). However the incidence of hypertension was highest in dogs with ADH (p = 0.017), followed by dogs with PDH, with the lowest levels in clinically healthy dogs (p = 0.019). Presence of microalbuminuria and albuminuria in clinically healthy dogs and dogs affected with HAC was significantly different (p < 0.001); incidences of albuminuria followed the same pattern of hypertension; highest incidence in dogs with ADH, and lowest level in clinically healthy dogs; but microalbuminuria showed a different pattern: clinically healthy dogs had highest incidences and dogs with ADH had lowest incidence. The presence of albuminuria was not associated with blood pressure values, regardless of whether dogs were clinically healthy or affected with ADH or PDH (p = 0.306).Conclusions
Higher incidence of hypertension and albuminuria, not microalbuminuria was seen in dogs affected with HAC compared to clinically healthy dogs; incidence of hypertension and albuminuria was significantly higher in dogs affected with ADH compared to PDH. However, presence of albuminuria was not correlated with systemic blood pressure. 相似文献175.
Dubey JP Vianna MC Sousa S Canada N Meireles S Correia da Costa JM Marcet PL Lehmann T Dardé ML Thulliez P 《The Journal of parasitology》2006,92(1):184-186
The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in 225 free-range chickens (Gallus domesticus) from Portugal was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT) and found in 61 chickens with titers of 1:5 in 8, 1:10 in 6, 1:20 in 3, 1:40 in 23, 1:80 in 5, 1:160 in 4, 1:320 in 8, and 1:640 or higher in 4. Hearts, leg muscles, and brains of 15 seropositive (MAT 1:10 or higher) chickens were bioassayed individually in mice. Tissue from 38 chickens with titers of 1:5 or less were pooled and fed to a T. gondii-free cat. Feces of the cat were examined for oocysts, but none was found. Toxoplasma gondii was isolated from 16 of 19 chickens with MAT titers of 1:10 or higher. Genotyping of 12 of these 16 isolates with polymorphisms at the SAG2 locus indicated that 4 were type III, and 8 were type II. None of the isolates was lethal for mice. Phenotypically, T. gondii isolates from chickens from Portugal were different from those of T. gondii isolates from chickens from Brazil. 相似文献
176.
Histiostoma papillata sp. n. (Acari: Histiostomatidae) is described from Victoria, Australia. It was found in the fins and gills of juvenile Murray cod, Maccullochella peelii peelii (Mitchell), where it appeared to inflict injuries thought to be responsible for the mortality of fish in a diet trial. 相似文献
177.
Vinícius Rozendo Vianna Gabriel Carvalho Costa Pedro Rodrigues de Alencar Raphael Igor Dias 《Austral ecology》2023,48(6):1154-1167
Roads are responsible for different negative effects on wildlife, including the isolation of populations and the direct reduction of biodiversity. Millions of animals are killed in traffic every year. Despite that, the influence of animal behaviour on the probability of animal-vehicle collisions has been overlooked by the literature. The blue-black grassquit (Volatinia jacarina) is a small, migratory, dichromatic species. During the breeding period, males vigorously defend small, clustered territories. Here, we investigated how the number of roadkills varied spatially and temporally in relation to the breeding activity, density, and sex of grassquits. We demonstrated that the variation in the movement dynamics and reproductive behaviour of the grassquits are associated with a great number of casualties. Road mortality is higher during the breeding period but is not associated with juvenile dispersion. As expected, males have a higher probability of being road-killed than females, suggesting that territory defence and mate searching may increase the risk of mortality. On the other hand, the clustering of individuals may not increase the risk of road fatalities, suggesting that other environmental attributes may influence the probability of being killed on roads. 相似文献
178.
Horz HP Scheer S Huenger F Vianna ME Conrads G 《Journal of microbiological methods》2008,72(1):98-102
We evaluated two DNA preparation strategies (MolYsis, Molzym GmbH & Co. KG, Bremen, Germany) and Pureprove, SIRS-Lab GmbH, Jena, Germany) to selectively extract bacterial DNA from human clinical samples. By testing 16 oral samples we found that human DNA could be largely eliminated while detectable levels of bacterial DNA were obtained with all samples. Both approaches hold great potential for microbial diagnostic systems. 相似文献
179.
Lisauskas SF Cunha NB Vianna GR Mendes EA Ramos GL Maranhão AQ Brígido MM Almeida JO Baptista HA Motta FL Pesquero JB Aragão FJ Rech EL 《Biotechnology letters》2008,30(12):2063-2069
Human factor IX is synthesized in the liver and secreted in the blood, where it participates in a group of reactions involving
coagulation factors and proteins that permit sanguinary coagulation. In this work two lines of transgenic mice were developed
to express the FIX gene in the mammalian glands under control of milk β-casein promoter. The founding females secreted the FIX in their milk
(3% total soluble protein). The stable integration of transgene was confirmed by southern blot analysis. The presence of the
FIX recombinant protein in the milk of transgenic females was confirmed by western blot and the clotting activity was revealed
in blood-clotting assays. The coagulation activity in human blood treated with recombinant FIX increased while the time of
coagulation decreased. Our results confirm the production of a large amount of recombinant biologically active FIX in the
mammary gland of transgenic mice. 相似文献
180.
Throughout 1 year, from October 2003 to September 2004, 88 visits to the landing site of a small urban fishery (APREBAN) in Rio de Janeiro city were conducted and 816 specimens of Rhizoprionodon lalandii were analysed. The sample, mostly females, was composed of two cohorts: young-of-the-year were abundant in spring and summer and adults predominated in autumn and winter. Gravid females were most abundant from April to June, whereas post-partum females composed most of the catch in August to September. Adult males were present all year although were more abundant between February and July. No neonates were captured during the study and most embryos collected measured slightly below the reported total length ( L T ) at time of birth ( L 0 ) for the species, suggesting that parturition may occur slightly outside the main fishing grounds or that neonates were not captured in commercial gillnets set at this time of the year. The mean L T at maturity ( L T50 ) for males was 578 mm and females matured between 620 and 660 mm, although a precise estimate of L T50 for females could not be determined. The total length ( L T ) and total mass ( M T ) relationship was calculated for both sexes and showed no significant differences. The mean condition factor increased steadily from February to July followed by a steep decrease in values relative to females in August and September, suggesting a pupping season. The present study area can be classified as a coastal juvenile habitat and a probable mating ground for R. lalandii . 相似文献