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681.
Emissions of CO2 and N2O from a pasture soil from Madagascar—Simulating conversion to direct‐seeding mulch‐based cropping in incubations with organic and inorganic inputs
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Michel Rabenarivo Nicole Wrage‐Moennig Jean‐Luc Chotte Lilia Rabeharisoa Tantely M. Razafimbelo Lydie Chapuis‐Lardy 《植物养料与土壤学杂志》2014,177(3):360-368
In the highlands of Madagascar, agricultural expansion gained on grasslands and cropping systems based on direct seeding with permanent vegetation cover are emerging as a means to sustain upland crop production. The objective of this study was to examine how such agricultural practices affect greenhouse‐gas emissions from a loamy Ferralsol previously used as a pasture. We conducted an experiment under controlled laboratory conditions combining cattle manure, crop residues (rice straw), and mineral fertilizers (urea plus NPK or di‐NH4‐phosphate) to mimic on‐field inputs and examined soil CO2 and N2O emissions during a 28‐d incubation at low and high water‐filled pore space (40% and 90% WFPS). Emissions of N2O from the control soil, i.e., soil receiving no input, were extremely small (< 5 ng N2O‐N (g soil)–1 h–1) even under anaerobic conditions. Soil moisture did not affect the order of magnitude of CO2 emissions while N2O fluxes were up to 46 times larger at high soil WFPS, indicating the potential influence of denitrification under these conditions. Both CO2 and N2O emissions were affected by treatments, incubation time, and their interactions. Crop‐residue application resulted in larger fluxes of CO2 but reduced N2O emissions probably due to N immobilization. The use of di‐NH4‐phosphate was a better option than NPK to reduce N2O emissions without increasing CO2 fluxes when soil received mineral fertilizers. Further studies are needed to translate the findings to field conditions and relate greenhouse‐gas budgets to crop production. 相似文献
682.
Wakayama T Tabar V Rodriguez I Perry AC Studer L Mombaerts P 《Science (New York, N.Y.)》2001,292(5517):740-743
Embryonic stem (ES) cells are fully pluripotent in that they can differentiate into all cell types, including gametes. We have derived 35 ES cell lines via nuclear transfer (ntES cell lines) from adult mouse somatic cells of inbred, hybrid, and mutant strains. ntES cells contributed to an extensive variety of cell types, including dopaminergic and serotonergic neurons in vitro and germ cells in vivo. Cloning by transfer of ntES cell nuclei could result in normal development of fertile adults. These studies demonstrate the full pluripotency of ntES cells. 相似文献
683.
684.
Howlett NG Taniguchi T Olson S Cox B Waisfisz Q De Die-Smulders C Persky N Grompe M Joenje H Pals G Ikeda H Fox EA D'Andrea AD 《Science (New York, N.Y.)》2002,297(5581):606-609
Fanconi anemia (FA) is a rare autosomal recessive cancer susceptibility disorder characterized by cellular hypersensitivity to mitomycin C (MMC). Six FA genes have been cloned, but the gene or genes corresponding to FA subtypes B and D1 remain unidentified. Here we show that cell lines derived from FA-B and FA-D1 patients have biallelic mutations in BRCA2 and express truncated BRCA2 proteins. Functional complementation of FA-D1 fibroblasts with wild-type BRCA2 complementary DNA restores MMC resistance. Our results link the six cloned FA genes with BRCA1 and BRCA2 in a common pathway. Germ-line mutation of genes in this pathway may result in cancer risks similar to those observed in families with BRCA1 or BRCA2 mutations. 相似文献
685.
G protein-coupled receptors in Anopheles gambiae 总被引:3,自引:0,他引:3
Hill CA Fox AN Pitts RJ Kent LB Tan PL Chrystal MA Cravchik A Collins FH Robertson HM Zwiebel LJ 《Science (New York, N.Y.)》2002,298(5591):176-178
We used bioinformatic approaches to identify a total of 276 G protein-coupled receptors (GPCRs) from the Anopheles gambiae genome. These include GPCRs that are likely to play roles in pathways affecting almost every aspect of the mosquito's life cycle. Seventy-nine candidate odorant receptors were characterized for tissue expression and, along with 76 putative gustatory receptors, for their molecular evolution relative to Drosophila melanogaster. Examples of lineage-specific gene expansions were observed as well as a single instance of unusually high sequence conservation. 相似文献
686.
Ruhl S Casson N Kaiser C Thoma R Pospischil A Greub G Borel N 《Veterinary microbiology》2009,135(1-2):169-174
Bovine abortion of unknown infectious aetiology still remains a major economic problem. In this study, we focused on a new possible abortigenic agent called Parachlamydia acanthamoebae. Retrospective samples (n=235) taken from late-term abortions in cattle were investigated by real-time diagnostic PCR for Chlamydiaceae and Parachlamydia spp., respectively. Histological sections of cases positive by real-time PCR for any Chlamydia-related agent were further examined by immunohistochemistry using specific antibodies. Chlamydophila abortus was detected only in three cases (1.3%) by real-time PCR and ArrayTube Microarray playing a less important role in bovine abortion compared to the situation in small ruminants in Switzerland. By real-time PCR as many as 43 of 235 (18.3%) cases turned out to be positive for Parachlamydia. The presence of Parachlamydia within placental lesions was confirmed in 35 cases (81.4%) by immunohistochemistry. The main histopathological feature in parachlamydial abortion was purulent to necrotizing placentitis (25/43). Parachlamydia should be considered as a new abortigenic agent in Swiss cattle. Since Parachlamydia may be involved in lower respiratory tract infections in humans, bovine abortion material should be handled with care given the possible zoonotic risk. 相似文献
687.
Neumann EJ Grinberg A Bonistalli KN Mack HJ Lehrbach PR Gibson N 《Veterinary microbiology》2009,138(3-4):297-303
The porcine reproductive and respiratory syndrome virus (PRRSV) is an enveloped RNA virus. Virions of PRRSV contain six membrane proteins: the major proteins GP5 and M and the minor proteins GP2, GP3, GP4, and E. The GP5 is the major envelope proteins, which was involved in the formation and infectivity of PRRSV by coaction with other membrane proteins. Here, to determine the function of alone GP5 envelope protein in viral entry, we investigated the formation and infectivity of GP5-pseudotyped virus particles. By co-transfection of GP5 expression plasmids with murine leukemia virus (MuLV) based retroviral vectors (pHIT60, encoding MuLV Gag-Pol; pHIT111, encoding an MuLV genome with a β-galactosidase reporter gene) into 293 T cells and analysis of the culture medium using ultracentrifugation, Western blot, and infection assay. We observed that the GP5 envelope protein was incorporated into the MuLV retroviral vectors to generate an pseudotyped murine leukemia virus, which was infectious to PAM and Mack-145 target cells and displayed the same host range with wild-type PRRSV. The infection of the pseudotyped virus on PAM target cells is effectively neutralized by polyclonal antibodies specific for PRRSV or GP5. The results suggested that the GP5 protein may play a key role in the viral entry by interacting with the host cell receptor. The GP5-pseudotyped virus will be useful in the identification of the cellular receptor binding with GP5 protein. 相似文献
688.
Background
The performance of piglet weight gain is strongly dependent on the sow''s ability to meet the demand for adequate milk. Postparturient disorders, especially those subsumed under the term postpartum dysgalactia syndrome (PPDS), can alter or reduce the milk production sensitively, resulting in starving piglets. The aim of this study was to gather further information about the prevalence of different bacterial species in the anterior and posterior mammary glands of sows with respect to the clinical appearance of PPDS.Methods
In this study, the health status of 56 sows after farrowing was determined with special regard to mastitis and dysgalactia. Pooled milk samples from anterior and posterior glands were taken from both affected and non-affected animals and analysed bacteriologically for the presence of a wide spectrum of different pathogens.Results
Mainly Escherichia coli, staphylococci and streptococci were detected in high percentages but without significant differences in healthy and diseased animals and anterior and posterior glands. However, the large percentages of coliform bacteria suggested a transmission route via faecal contamination.Conclusion
In this study, the prevalence of different bacteria in anterior and posterior glands in PPDS positive and negative sows was analysed. No significant differences in bacteria of healthy and diseased sows were assessed. Therefore, the development of clinical PPDS and actual infection seems to be largely dependant on individual resistance in single sows. 相似文献689.
The objective of this study was to determine the effect of vitamin E source on plasma vitamin E concentration. Five different formulations of natural source vitamin E (4,000 IU/day) were supplemented to Standardbred mares (n = 4 per group) for 14 days. Treatment 1 was given 10 g of 400 IU/g natural acetate (RRR-α-tocopheryl-acetate) powder, treatment 2 was given 6.66 g of 600 IU/g natural acetate powder, treatment 3 was given 6.66 g of 600 IU/g natural alcohol (RRR-α-tocopherol) powder, treatment 4 was given 20 g of 200 IU/g micellized natural alcohol powder, and treatment 5 was given 8 mL of 500 IU/mL micellized natural alcohol liquid. Blood samples were collected before supplementation (day 0), after day 7 and day 14 of supplementation, and analyzed for plasma α-tocopherol. Treatments 1, 2, and 3 increased (P < .05) from days 0 to 7, but remained similar at day 14. Treatments 4 and 5 also increased (P = .004, and P < .0001, respectively) from days 0 to 7 and were higher (P < .05) than treatment 1, 2, and 3. Plasma levels peaked at day 7 and either plateaued or decreased (treatment 5, P = .004) at day 14. The micellized alcohol formulations remained elevated (treatment 4) or decreased (treatment 5) after achieving peak blood concentration and, as hypothesized, tended to have plasma concentrations higher than the other vitamin E forms. Care should be taken to ensure that the most active biologically available form of vitamin E is provided in the diet to maximize its efficiency. 相似文献
690.
Ariane Schweighauser Dr med vet DACVIM ; Iwan A. Burgener Dr med vet DACVIM DECVIM ; Frédéric Gaschen Dr med vet DACVIM DECVIM ; Nicole Luckschander Dr med vet DACVIM DECVIM ; Andreas Hasler Dr med vet DACVIM ; Johann Lang Dr med vet DECVDI Thierry Francey Dr med vet DACVIM 《Journal of Veterinary Emergency and Critical Care》2009,19(4):363-368
Objectives – This case series describes 5 dogs with small intestinal intussusception and acute kidney injury due to infection with Leptospira interrogans serovar Australis.
Case Series Summary – Small intestinal intussusception was observed in 4 dogs diagnosed with acute kidney injury due to leptospirosis presented between 1997 and 2005. Intussusception was diagnosed at initial presentation or later during hospitalization. An additional dog fulfilling our inclusion criteria was presented to a small animal specialty clinic nearby and was included. Upon admission, all dogs were severely azotemic and thrombocytopenic. All 5 dogs showed the strongest microscopic agglutination test serology reaction to L. interrogans serovar Australis. Two dogs survived with no apparent residual renal damage, 1 survived with subsequent mild chronic kidney disease, and 2 dogs were euthanized at the owners' request due to a guarded prognosis.
New or Unique Information Provided – Intussusception can occur or may be seen in dogs with leptospirosis due to L. interrogans serovar Australis and patients should be monitored closely for this potential complication. As all 5 dogs described in this case series showed the highest titer for L. interrogans serovar Australis, these precautions may be especially applied in geographic areas where this particular serovar is seen. 相似文献
Case Series Summary – Small intestinal intussusception was observed in 4 dogs diagnosed with acute kidney injury due to leptospirosis presented between 1997 and 2005. Intussusception was diagnosed at initial presentation or later during hospitalization. An additional dog fulfilling our inclusion criteria was presented to a small animal specialty clinic nearby and was included. Upon admission, all dogs were severely azotemic and thrombocytopenic. All 5 dogs showed the strongest microscopic agglutination test serology reaction to L. interrogans serovar Australis. Two dogs survived with no apparent residual renal damage, 1 survived with subsequent mild chronic kidney disease, and 2 dogs were euthanized at the owners' request due to a guarded prognosis.
New or Unique Information Provided – Intussusception can occur or may be seen in dogs with leptospirosis due to L. interrogans serovar Australis and patients should be monitored closely for this potential complication. As all 5 dogs described in this case series showed the highest titer for L. interrogans serovar Australis, these precautions may be especially applied in geographic areas where this particular serovar is seen. 相似文献