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排序方式: 共有115条查询结果,搜索用时 13 毫秒
61.
62.
KM Morton SP de Graaf A Campbell LM Tomkins WM Chis Maxwell G Evans 《Reproduction in domestic animals》2005,40(5):422-428
Ovum pick-up (OPU) was performed three times on adult ewes after synchronization with (n = 4) or without (n = 4) FSH treatment to investigate the effects of FSH treatment on the number of ovarian follicles, oocytes recovered, oocyte quality and development in vitro. FSH treatment increased the number of ovarian follicles (85 vs 162) and oocytes recovered (33 vs 91), although recovery rate was similar for ewes with and without FSH (91/162, 56.2% and 33/85, 38.8% respectively). Of the oocytes recovered, those classified as grades I and II were similar between ewes with (78/91, 85.7%) and without FSH treatment (27/33, 81.8%). The number of ovarian follicles was similar after repeated OPU for ewes treated with FSH, but for ewes not treated with FSH the number of ovarian follicles decreased with repeated OPU. The number of oocytes recovered decreased for FSH-treated ewes only, while the oocyte recovery rate and proportion of oocytes classified as grades I and II were not affected by repeated OPU. Oocyte cleavage (46/78, 58.9% and 19/24, 79.2%) and blastocyst formation (35/46, 76.1% and 12/19, 63.2% respectively) were similar for ewes with and without FSH treatment. The number of ovarian follicles varied between ewes (p < 0.05) although the number of oocytes recovered and oocyte development in vitro were similar between ewes. 相似文献
63.
American beech (Fagus grandifolia Ehrh.) in the understory of northern hardwood stands can interfere with the development of more desirable species such as sugar maple (Acer saccharum Marsh.). Yet, managers have had only limited methods for identifying stands where beech might dominate a new cohort. We examined five uneven-aged stands in New York State to determine the degree of influence that understory beech has on species development after a cutting treatment. No significant differences between stands were found, allowing us to develop a single model for evaluation. Understory beech was assessed using a species index value (SIV), which measures the proportion of stems, weighted by height, for a species on a milacre plot. We used a 5×5 transition matrix to compare pre- and post-cut beech importance levels. Stand-level trends showed an overall increase in the proportion of sample plots with higher levels of understory beech after cutting, with the likelihood of change on individual plots dependent on their pre-cut status. Plots with either no beech or very high levels of beech changed little after cutting, while beech was more likely to reach critical levels of dominance when pre-cut SIV was medium or higher. The transition matrix gives forest managers a means to forecast the probable level of future beech importance following cutting, based upon precursor conditions. 相似文献
64.
Molecular mapping of QTL for southwestern corn borer resistance, plant height and flowering in tropical maize 总被引:12,自引:0,他引:12
M. M. Khairallah M. Bohn C. Jiang J. A. Deutsch D. C. Jewell J. A. Mihm A. E. Melchinger D. González-De -León D. A. Hoisington 《Plant Breeding》1998,117(4):309-318
Development of multiple insect resistance in tropical maize represents a major effort of the maize breeding programme at CIMMYT. Resistance to the southwestern corn borer (SWCB) is polygenically controlled with primarily additive gene action. Our main objective was to identify quantitative trait loci (QTL) involved in resistance to SWCB. Other objectives were to detect QTL in the same population for plant height, female flowering, and the anthesis-silking interval (ASI). A population of 472 F2 individuals derived from a cross between the susceptible line Ki3 and the resistant inbred CML139, was restriction fragment length polymorphism (RFLP) genotyped using 110 maize probes. F3 families were rated for leaf-feeding damage after artificial infestation at one location in three consecutive years. Height and flowering were measured in protected trials in two locations. QTL analyses were conducted using joint composite interval mapping. Seven QTL on chromosomes 3, 5, 6, 8, and 9 explained 30% of the phenotypic variance (σ2p) for SWCB damage. Most QTL alleles conferring resistance were contributed from CML139. QTL showed dominance, partial dominance and additive gene action. Eleven QTL dispersed across the genome were determined to affect plant height and explained 43% of σ2p. Four of these were in close proximity to loci with qualitative effects on plant height. Thirteen QTL (50% of sigma;2p) were identified for days to female flowering and nine (30% of σ2p) for ASI. Our results, along with those from other mapping studies at CIMMYT, are allowing us to formulate marker-assisted selection schemes to complement the breeding efforts for such complex traits as borer resistance. 相似文献
65.
Unlu NZ Bohn T Francis D Clinton SK Schwartz SJ 《Journal of agricultural and food chemistry》2007,55(4):1597-1603
Tomato sauces were produced from unique tomato varieties to study carotenoid absorption in humans. Tangerine tomatoes, high in cis-lycopene, especially prolycopene (7Z,9Z,7'Z,9'Z), and high-beta-carotene tomatoes as an alternative dietary source of beta-carotene were grown and processed. Sauces were served after 2 week washout periods and overnight fasting for breakfast to healthy subjects (n = 12, 6M/6F) in a randomized crossover design. The serving size was 150 g (containing 15 g of corn oil), tangerine sauce containing 13 mg of lycopene (97.0% as cis-isomers) and high-beta-carotene sauce containing 17 mg of total beta-carotene (1.6% as the 9-cis-isomer) and 4 mg of lycopene. Blood samples were collected 0, 2, 3, 4, 5, 6, 8, and 9.5 h following test meal consumption and carotenoids determined in the plasma triacylglycerol-rich lipoprotein fraction by HPLC-electrochemical detection. Baseline-corrected areas under the concentration vs time curves (AUC) were used as a measure of absorption. AUC0-9.5h values for total lycopene in the tangerine sauce group were 870 +/- 187 (nmol.h)/L (mean +/- SEM) with >99% as cis-isomers (59% as the tetra-cis-isomer). The AUC0-9.5h values for total beta-carotene and lycopene after consumption of the high-beta-carotene sauce were 304 +/- 54 (4% as 9-cis-carotene) and 118 +/- 24 (nmol.h)/L, respectively. Lycopene dose-adjusted triacylglycerol-rich lipoprotein AUC responses in the tangerine sauce group were relatively high when compared to those in the literature and the high-beta-carotene group. The results support the hypothesis that lycopene cis-isomers are highly bioavailable and suggest that special tomato varieties can be utilized to increase both the intake and bioavailability of health-beneficial carotenoids. 相似文献
66.
Bohn AA Wills TB West CL Tucker RL Bagley RS 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(3):315-320
BACKGROUND: Diagnosis of central nervous system (CNS) abnormalities in dogs can be challenging antemortem. Historically, cerebrospinal fluid (CSF) analysis has been used for routine diagnostic evaluation of animals with suspected neurologic disease; however, with increasing availability of magnetic resonance (MR) imaging, the need for concurrent CSF analysis may be questioned. OBJECTIVE: The purpose of this study was to retrospectively assess and compare the diagnostic information contributed from MR imaging and CSF analysis in a population of dogs presenting with neurologic disease. METHODS: Results of concurrent MR imaging and CSF analysis were evaluated in dogs presented for neurologic diseases. Based on clinical diagnosis, the sensitivity of CSF analysis and MR imaging for detecting a nervous system abnormality was calculated. Dogs with diagnoses confirmed by other diagnostic modalities were also evaluated separately. RESULTS: A total of 256 dogs were included in the study. For clinical diagnoses in which abnormalities were expected, MR imaging abnormalities were found in 89% and CSF abnormalities in 75% of dogs; CSF abnormalities were more common than MR imaging abnormalities only in inflammatory CNS disease. The majority of CSF abnormalities were nonspecific; an etiologic diagnosis was determined in only 2% of CSF samples. MR imaging excelled in detecting structural disorders, revealing 98% of vertebral abnormalities. In confirmed cases (n = 55), 76% of MR images and 9% of CSF samples were diagnostic. When intervertebral disk disease (IVDD) and vertebral malformation were excluded from analysis (n = 16 remaining), 25% of MR images and 6% of CSF cytology results were highly indicative of the confirmed diagnoses; CSF titer results provided the diagnosis in 25% of these cases. CONCLUSION: CSF analysis may not be necessary when MR findings of IVDD or vertebral malformation/instability are obvious; however, when the cause of neurologic disorder is uncertain, concurrent MR imaging and CSF analysis provides the greatest assistance in establishing a clinical diagnosis. 相似文献
67.
M Ruiz de Arcaute LM Ferrer D Lacasta JM González M De las Heras M Borobia JJ Ramos 《Australian veterinary journal》2020,98(9):438-441
At the slaughterhouse, 1465 culled sheep heads were studied in order to identify disorders of the mandibular cheek teeth. Of these, 227 (15.5%) had evidence of osteomyelitis. The lesional profile showed that the mandible was affected in a similar proportion on both sides (46.7% on the right side vs 50.7% on the left side), mainly in the middle region (55.3%) and with most of the lesions closed without fistulisation (89.4%). In addition, swelling was palpable, with an increase in thickness in the area of the affected body (2.65 ± 0.065 cm vs 1.74 ± 0.030 cm). In 78.6% of the animals, the regional lymph nodes were enlarged. Concerning the mandibular cheek teeth, more than half of the animals lacked at least one tooth (57.0%), with the first premolar being the most frequently missing tooth (34.8%) and the third molar the least (8.2%). The impaction of food around the teeth was very common with the posterior molars being more frequently affected. In the knowledge of the authors, this is the first study that analyses the prevalence of mandibular molar and premolar disorders in sheep, and these are revealed as an important condition affecting culled sheep. 相似文献
68.
Endometritis is an important cause of reproductive pathology in the horse. Endometrial cytology preparations from unguarded swabs, guarded swabs or brushes, cap of a guarded swab, low volume lavage or even an endometrial biopsy sample can be utilised to rapidly evaluate uterine health. These cells can easily be stained with a modified Wright's stain and evaluated for the presence or absence of inflammatory cells and pathogens. Commonly visualised cell types are easily identified with a traditional light microscope at 400× or 1000× magnification. This technique provides an easy and rapid way to diagnose endometritis in the horse. 相似文献
69.
Immunohistochemical Expression of Cyclooxygenase‐2 (COX‐2) in Feline Endometrial Adenocarcinoma and in Normal and Hyperplastic Endometria 下载免费PDF全文
AL Saraiva R Payan‐Carreira F Gärtner I Santana A Rêma LM Lourenço MA Pires 《Reproduction in domestic animals》2015,50(2):333-340
Cyclooxygenase‐2 (COX‐2) is overexpressed in several human and animal neoplasms, including the human endometrial carcinoma. It has been suggested as a prognostic marker and a potential therapeutic target. This study aimed to (i) clarify histological aspects of feline endometrial adenocarcinomas (FEA) of the papillary serous type and (ii) characterize COX‐2 immunohistochemical expression in normal, hyperplastic and neoplastic endometrium in this species. Archived paraffin‐embedded tissue samples of 33 FEA, eight cystic endometrial hyperplasias (CEHs) and 21 samples of normal, healthy endometrium in the follicular (FS; n = 10) and luteal (LS; n = 11) stages were evaluated. Histological evaluation of haematoxylin and eosin‐stained sections of the FEA revealed a papillary proliferation of neoplastic cells of serous type, accompanied by clear and multinucleated cells. Other architectural arrangements mainly included solid and tubular growth. Randomly distributed areas of necrosis within the tumours were commonly observed. Invasion of the myometrium, of the serosa and of the vascular and/or lymphatic vessels was not constant features. The mean number of mitoses was higher in FEA compared to non‐neoplastic endometrium. COX‐2 scores were lower in FEA (p = 0.003) and CEH (p = 0.05) when compared to normal epithelium (NE). The loss of the membrane apical reinforcement in epithelial cells was observed in FEA samples, which was accompanied by the dislocation of COX‐2 labelling into the cytoplasm and the perinuclear area; in contrast, in epithelial cells in the healthy and hyperplastic endometria, the immunoreaction showed the characteristic pattern of apical membrane reinforcement, suggestive of the membrane polarization. COX‐2 epithelial scores were higher in the FS than in the LS. No differences were found in stromal COX‐2 expression between normal, CEH and FEA groups, but it was higher in the LS than in the FS. In summary, loss of COX‐2 compartmentalization in neoplastic epithelial cells might be one of the molecular events underlying endometrial carcinogenesis. 相似文献
70.