胞质雄性不育性在叶用芥菜上的利用     

Nikornpun  M.　N. Senapa 《中国蔬菜》2004,1(1):10-11

以从美国威斯康星大学引进的叶用芥菜胞质雄性不育系叶用4-4为母本,以泰国清迈大学选育出的8个优良叶用芥菜品种为转育父本,杂交后连续回交4代(BC4),再将BC4与优良叶用芥菜品种40R2-3-4配制8个杂交组合,其中2个组合(4-4 × 19-H-12)×40R2-3-4和(4-4 × 2R2)×40R2-3-4结球率为100％,产量比商用品种分别高34％和13％,比其亲本分别高25％和5％。  相似文献   

Clone identification and genetic relationship among vine cacti from the genera Hylocereus and Selenicereus based on RAPD analysis   总被引：1，自引：0，他引：1  

N. Tel-Zur  S. Abbo  D. Bar-Zvi  Y. Mizrahi   《Scientia Horticulturae》2004,100(1-4):279-289

Clones of Hylocereus and of Selenicereus species were distinguished from each other by the banding pattern generated by one to nine 10-mer oligonucleotide primers in the random amplified polymorphic DNA (RAPD) reaction. RAPD analysis was also applied to estimate the genetic relationship among five Hylocereus and nine Selenicereus species. A dendrogram was constructed based on a data matrix of 173 polymorphic bands originated by nine primers. Two groups were identified, one consisting of Hylocereus species and the other consisting of Selenicereus species. These results are consistent with the accepted taxonomic classification of the genera studied. The principal coordinate analysis (PCO), i.e. the plot drawn on the basis of the RAPD data, clearly distinguished between three groups, namely, Hylocereus species, S. megalanthus and the rest of the Selenicereus species studied. PCO thus strongly support the notion that the tetraploid S. megalanthus is an exception among the Selenicereus group. The RAPD results support our hypothesis regarding the allopolyploid (rather than autopolyploid) origin of this species.  相似文献   

Factors affecting the development of disease symptoms in potatoes infected by <Emphasis Type="Italic">Tobacco rattle virus</Emphasis>     

D.J. Robinson  M.F.B. Dale  D. Todd 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(9):921-928

Infection of potato plants with Tobacco rattle virus by its nematode vector can have different outcomes, including the development of spraing symptoms in progeny tubers. A novel syndrome described here comprises a generalized mottle in leaves on all stems, together with virtually total failure to produce daughter tubers. The outcome of infection depends partly on the potato genotype, but field trials with 15 varieties showed that the incidence and severity of spraing symptoms at three sites differed. There was no evidence that this was due to differences in virulence among the virus isolates at the sites, but it was probably the result of environmental differences that influenced the numbers and activity of the vector nematodes. At the most severely affected site, spraing symptoms were found in all varieties tested, except Record, including several that were not affected at the other two sites. Taking both severity and incidence of symptoms into account, the ranking of varieties was similar at each site. The incidence of spraing symptoms was greater in larger than in smaller tubers, and increased with later harvest dates, but did not increase when early harvested tubers were stored. Tobacco rattle viruswas detected in the roots of many of the weeds growing at one of the sites and in the roots of a few plants of the subsequent barley crop.  相似文献   

Diagnosis of Congenital Cardiac Right-to-left Shunts with ^99mTc-macroaggregated Albumin     

Federica Morandi  DVM  MS    Gregory B. Daniel  DVM  MS    Rebecca E. Gompf  DVM  MS    Anne Bahr  DVM  MS 《Veterinary radiology & ultrasound》2004,45(2):97-102

Diagnosing right-to-left congenital cardiac shunts can be difficult. Cardiac catheterization and angiocardiography represent the traditional gold standard for diagnosis, but they are invasive. Nuclear scintigraphy using 99mTc-macroaggregated albumin (MAA) has been employed in humans as an alternate method of diagnosis. This study reviews eight dogs presented for evaluation of a suspect right-to-left cardiac shunt that were examined using 99mTc-MAA. In all, 2-4 mCi (74-148 MBq) of reduced particle 99mTc-MAA were injected IV in a cephalic vein and static images of the whole body, including right and left lateral, dorsal, and ventral views, were acquired for 60 s and stored into a 256 x 256 x 16 matrix. Shunt fractions were calculated. One dog with radiopharmaceutical distribution limited to the lungs did not have a shunt. Seven dogs had distribution of the radiopharmaceutical outside the pulmonary capillary bed, indicating bypassing of the pulmonary capillary circulation due to a right-to-left shunt. Four dogs had 99mTc-MAA within the brain. Three dogs that did not have brain uptake, but instead had a sharp cutoff of radioactivity at the level of the front limbs and neck, were diagnosed with reverse patent ductus arteriosus (PDA). The asymmetric distribution of the radiopharmaceutical is due to the location of the shunt, distal to the brachiocephalic trunk and left subclavian artery. Shunt fractions of dogs with extrapulmonary radioactivity ranged from 40% to 59%. Nuclear scintigraphy with 99mTc-MAA is a quick alternative method of diagnosing right-to-left cardiac shunts that permits quantification of shunt fraction. Distinguishing between reverse PDA and other right-to-left shunts may be possible based on the radiopharmaceutical distribution.  相似文献   

Spontaneous neoplasms of lagomorphs.     

J Jill Heatley  Annette N Smith 《Veterinary Clinics of North America: Exotic Animal Practice》2004,7(3):561-77, v

Many of the same neoplastic processes reported in companion animal medicine have been documented in lagomorphs. With only a few reports in the literature regarding rabbits and hares, the behavior of many of these tumors cannot be predicted. Further, based on limited current knowledge, the practitioner is left to make decisions for diagnostics and therapeutics in these cases based upon current recommendations for companion animals with adjustments for lagomorph physiology. We hope that this review of lagomorph neoplasia will inform the general practitioner of the occurrence of these tumors, promote further documentation and research of these processes in rabbits, and encourage the practitioner of rabbit medicine along with rabbit owners to consult with veterinary oncologists regarding neoplastic processes in rabbits rather than just giving a guarded prognosis.  相似文献   

Magnetic resonance imaging of a brain abscess in a 10-month-old filly     

F. Audigié  DVM  PhD    J. Tapprest  DVM  PhD    C. George  DVM    D. Didierlaurent  N. Foucher  F. Faurie  DVM    M. Houssin  DVM    J.-M. Denoix  DVM  PhD 《Veterinary radiology & ultrasound》2004,45(3):210-215

The purpose of this paper was to correlate the magnetic resonance imaging (MRI) characteristics of a mature brain abscess in a horse with histopathologic alterations of brain tissue. Eight months after the onset of clinical signs, MRI of the brain of a 10-month-old filly was performed. A large space-occupying lesion in the right cerebral hemisphere was identified. This space-occupying lesion was delineated by a thick and well-defined capsule that was isointense to brain parenchyma on the T1-weighted images and with a markedly hypointense on the T2-weighted images. The identification of such a capsule is highly diagnostic of a mature brain abscess. The lesion seen on MR images was confirmed at necropsy where a large abscess of the right hemisphere was observed. Streptococcus zooepidemicus and Pseudomonas aeruginosa were isolated from the abscess. Based on histopathologic examination, the signal characteristics of the capsule on T1-weighted and T2-weighted images were found to be due to the presence of numerous hemosiderin-laden macrophages. These results are in agreement with previous studies on human patients. This report confirms the value of MRI in the diagnosis of equine brain diseases.  相似文献   

Molecular epidemiology of two fowl cholera outbreaks on a free-range chicken layer farm.     

P Zhang  N Fegan  I Fraser  P Duffy  R E Bowles  A Gordon  P J Ketterer  W Shinwari  P J Blackall 《Journal of veterinary diagnostic investigation》2004,16(5):458-460

Two outbreaks of fowl cholera on a multiage free-range egg farm were investigated. The outbreaks occurred in 1994 and 2002. A total of 22 strains of Pasteurella multocida were available for study, 11 from the 1994 outbreak and 11 from the 2002 outbreak. Lesions typical of acute fowl cholera were seen in the 1994 outbreak, whereas both acute and chronic fowl cholera occurred in the 2002 outbreak. The isolates were examined in an extended phenotypic typing methodology, by a P. multocida-specific polymerase chain reaction (PCR), by the Heddleston somatic serotyping scheme, and by restriction endonuclease analysis (REA) typing using the enzyme HpaII. All 22 strains had the same phenotypic properties, all were confirmed as P. multocida by PCR, all were Heddleston serovar 4, and all had the same REA pattern. The results indicate that these 2 outbreaks were caused by the same clone of P. multocida--despite the 8-year time period between the outbreaks.  相似文献   

Cell Proliferation in the Atretic Follicles of Buffalo and Cattle Ovary     

JB Feranil  N Isobe  T Nakao 《Reproduction in domestic animals》2004,39(6):405-409

The present study was carried out to describe the proliferative activity of granulosa and theca cells in healthy antral and atretic follicles of Philippine buffaloes (BU) and Holstein-Friesian (HF) cows. Paraffin sections of ovary were immunostained with mouse monoclonal antibody to proliferating cell nuclear antigen (PCNA). Then the follicles were classified into healthy and various stages of atretic follicles. The granulosa layer of healthy follicles had a significantly higher frequency of PCNA-positive cells than the early and advanced atretic follicles in both breeds. In the theca interna, significantly reduced populations of the PCNA-positive cells were found in both breeds as atresia progressed. Moreover, HF had significantly higher PCNA-positive cells in the theca interna of healthy, early atretic and advanced atretic follicles than BU. A reduction of PCNA-positive cells during atresia was also noted in the theca externa in both animals although differences were not significant. The results of the present work suggest that the proliferative activity of granulosa and theca cells decreases in association with follicular atresia in the BU similar to HF. Furthermore, a significantly deficient cell proliferative activity of theca interna was found in BU compared with HF.  相似文献   

Clostridium difficile diarrhea: infection control in horses.     

Viveca B?verud 《Veterinary Clinics of North America: Equine Practice》2004,20(3):615-630

C difficile has emerged as an important cause of diarrheic disease in horses. C difficile diarrhea is usually diagnosed in mature horses, mostly when they are treated with antimicrobials and hospitalized. It is important for clinicians at veterinary hospitals to have knowledge about the organism and the infection. To prevent C difficile diarrhea, judicious use of antimicrobials is important, as is minimizing different stress factors at the animal hospital or clinic. Infected horses must be isolated. Routine examination for C difficile and toxin A or B is recommended in horses with antibiotic-associated diarrhea. When treating foals for R equi pneumonia, it is important to avoid accidental ingestion of erythromycin by the dams. To reduce the number of environmental spores, thorough cleaning and surface disinfection of the animal hospital and clinic are important. Routine handwashing should be performed by all staff.  相似文献   

Cloning and characterization of a bovine genomic fragment homologous to epidermal growth factor genes          下载免费PDF全文

S.J. John  B.F. Benkel    S. Bilodeau-Goeseels 《Canadian journal of veterinary research》2004,68(4):293-301

Epidermal growth factor (EGF) is a potent mitogen for a variety of cell types. The 53-amino acid mature EGF protein is encoded by sequences in exons 20 and 21 of a gene spanning over 110 kb. In this study, we report the cloning and characterization of 7.5 kb of bovine genomic sequence homologous to exon 19 through 21 from EGF genes from other mammalian species. The cloned gene fragment had an unusual sequence composition in the form of an in-frame TGA codon in the coding sequence. The sequence was expressed at low levels in kidney tissue and the corresponding cDNA contained the TGA codon. The level of similarity between the bovine exonic sequence and the human, porcine, murine, feline, and canine corresponding sequences varied from 64% to 73%; however, when only sequences encoding the mature EGF protein were compared, the level of similarity between the bovine sequence and the sequence from these species was 59% to 66%. The sequence similarity of the deduced mature protein was lower (34% to 39%) than the sequence similarity of the deduced propeptide. Although the cloned sequences could originate from a bovine EGF pseudogene, the possibility exists that they originate from the functional EGF gene. An as yet unidentified mechanism to by-pass the stop codon would allow the synthesis of a functional EGF protein. Alternatively, the cloned sequence could originate from an EGF-like gene.  相似文献