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61.
In tomato ( Lycopersicon esculentum Mill.) a single dominant gene ( Frl) on chromosome 9 confers resistance to fusarium crown and root rot (crown rot) incited by Fusarium oxysporum f. sp. radicis-lycopersici. To identify randomly amplified polymorphic DNA (RAPD) markers linked to Frl, crown rot susceptible and resistant tomato lines were screened for polymorphisms using 1000 random 10-mer primers and three reliable RAPD markers were found linked to Frl (UBC #'s 116, 194, and 655). A codominant polymorphic PCR marker of TG101, a restriction fragment length polymorphic (RFLP) marker linked to Frl, was developed to facilitate the linkage studies. Using TG101 and the four RAPD markers, on a Frl segregating backcross population of 950 plants indicated that all belong to the same linkage group. The polymorphic allele order was found to be TG101 – 655 – 116 – 194 – Frl. UBC 194 was found to be 5.1 cM from Frl in this population. Furthermore, it was the only marker found in the resistant genotypes ‘Mocis’ and Fla 7226, whereas resistant genotypes ‘Momor’, Ohio 89-1, and Fla 7464 all had UBC 194 and UBC #'s 116, 194, and 655. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
62.
Canine cranial cruciate ligament rupture is often bilateral and asymmetrical, ranging from partial to complete rupture. The purpose of our diagnostic accuracy study was to assess the accuracy of 3 Tesla magnetic resonance imaging (MRI) detection of fiber loss and use of a visual analog scale in the diagnosis of complete versus partial cranial cruciate ligament rupture in 28 clinical dogs with unilateral complete rupture and contralateral partial rupture. Three Tesla MRI was performed on 56 stifles using sagittal sequences (T2‐weighted fast spin echo with fat saturation, proton density fast spin echo, and T2‐weighted 3D fast spin echo CUBE). Two MRI observers assessed the cranial cruciate ligament for fiber loss and completed a visual analog scale. The MRI data were compared to arthroscopy and clinical status. Accuracy classifying partial or complete rupture was assessed using receiver operating characteristic analysis. Compared to arthroscopy, for complete cranial cruciate ligament rupture, sensitivity, specificity, and accuracy of MRI detection of fiber loss were 0.78, 0.50–0.60, and 0.68–0.71, respectively, and, for partial tears, specificity was 1.00. An MRI visual analog scale score ≥79 was indicative of complete cranial cruciate ligament rupture (sensitivity 0.72–0.94 and specificity 0.71–0.84). Using a visual analog scale cut‐point ≥79, observers achieved good accuracy discriminating clinical status of partial or complete cranial cruciate ligament rupture (area under the curve 0.87–0.93). MRI evaluation for fiber loss and use of a visual analog scale are specific in stifles with clinically stable partial cranial cruciate ligament rupture. In stifles with clinically unstable complete cranial cruciate ligament rupture, both MRI tests are sensitive though not specific compared to arthroscopy. As a diagnostic imaging method, MRI may help guide treatment in patients with cranial cruciate ligament damage, particularly for stable partial rupture.  相似文献   
63.
Daily rhythm of tear production in normal horse   总被引:1,自引:0,他引:1  
Objective  This study was designed to assess the daily rhythm of tear production in clinically healthy horses, to compare left eye and right eye, and to evaluate the influence of time and gender.
Animal studied  For our study 18 horses (nine female and nine male) were subjected to three different light/dark (L/D) schedules: 12/12 L/D cycles, constant light (24/0 L/D) and constant darkness (0/24 L/D).
Procedures  In all subjects Schirmer tear tests were performed at 4-h intervals over a 24-h period.
Results  A circadian rhythm of tear production was found during the 12/12 L/D period and during constant darkness. Also our results showed a statistical significant difference comparing left eye and right eye, and between gender.
Conclusions  Our findings would suggest that the time of tear evaluation is significant in the diagnosis of tear film disorders, and that the difference between the two eyes and the two genders should be taken into consideration during the ophthalmic exam.  相似文献   
64.
The aim of this study was to evaluate total serum protein concentration measured using biuret reaction and the protein fractions determined using acetate cellulose electrophoresis in Ragusana donkeys (Equus asinus). Blood samples were collected from 68 clinically healthy female donkeys by jugular venipuncture. The serum levels of total proteins were determined using biuret method, and the separation of proteins was performed using acetate cellulose electrophoresis. Coefficients of variation were also calculated for within-assay precision, and were found to be less than 5% for α- and β1-globulins and 8% or less for albumin, β2-, and γ-globulins. A total of five protein fractions were separated and quantified: albumin, α-, β1-, β2-, and γ-globulins. Data obtained from young and adult subjects were compared using the Mann–Whitney U test. Reference intervals (2.5%-97.5% quantiles) were determined for total proteins (50.0-84.0 g/L), albumin (16.2-36.6 g/L), α-globulins (4.85-19.5 g/L), β1-globulins (2.25-10.35 g/L), β2-globulins (3.30-14.85 g/L), γ-globulins (10.0-30.5 g/L), and albumin/globulin ratio (0.41-1.13). In relation to age, statistically significant differences were found in total protein concentration and γ-globulins. The results obtained in the present study contributed to establish reference intervals of serum protein fractions obtained using acetate cellulose electrophoresis in female Ragusana donkeys to be used by practitioners for health control.  相似文献   
65.
Considering that workload can also be expressed in terms of estimated net transport cost (COT), the metabolic energy needed to transport unit mass of animal unit distance, the aim of our study was to describe the heart rate (HR), COT, and the total metabolic power requirement per kilogram (P) during different exercises (aerobic, anaerobic, and aerobic–anaerobic exercises). On the basis of their attitude, 25 horses, divided into five equal groups, traveled a distance of 6,000 m, walking at 100 m/min in a horse walker (group A); performed 20-minute treadmill walk at 130 m/min, average speed up gradient of 5% (group B); performed a 700-m-long show jumping course with 13 fences (group C); traveled a distance of 2,100 m galloping at a speed of 700 m/min (group D); and traveled a distance of 2,000 m trotting at a speed of 660 m/min (group E). On each horse, HR was continuously recorded by means of an equine HR monitor. COT was calculated with the following formula: (HR − 35) kg−1 m−1 103; P was calculated applying the formula: (HR − 35) min−1 kg−1. COT and P values, estimated from the mean HR, measured continuously during each experimental condition showed no linear relationship with HR and speed. The use of combined weight of horse and tack (group C and D) and horse, tack, and sulky (group E) statistically changed the results of formula application. COT and P change in different exercises and provide additional information about performance in athletic horses.  相似文献   
66.
The Food and Drug Administration multi-component regulatory procedure for determining polynuclear aromatic hydrocarbons in foods was recently used to survey 24 foodstuffs for the presence of these compounds. The procedure has a reliable limit of quantitation of 2 ppb. The potent carcinogen benzo(a)pyrene was detected in only one of the 24 products analyzed, at a level of 3 ppb. Pyrene and/or fluoranthene were found in 19 of the 24 samples examined, at levels ranging from less than 1 ppb to about 75 ppb. A comparison of the recent survey data to that obtained approximately 10 years ago reveals that the types and levels of polynuclear aromatic hydrocarbons found are essentially unchanged.  相似文献   
67.
A variety of food products containing nitrite were analyzed for 14 volatile N-nitrosamines by using a method demonstrated to be sensitive to 10 ppb. A total of 121 food samples were screened for volatile N-nitrosamine content. N-Nitrosopyrrolidine was confirmed in fried bacon at levels up to 139 ppb. N-Dimethylnitrosamine, N-nitrosopyrrolidine, and N-nitrosopiperidine were also confirmed in spice-cure mixtures at levels ranging from 50 to 2000 ppb.  相似文献   
68.
Effects of physiological variables (age, body weight and sex) on lipemia (total lipids, phospholipids, triglycerides and NEFA), fecal fat and chymotrypsin excretion were examined in dogs. On comparing various ages and body weights, they found statistically significant differences, while only total lipids showed a statistically significant difference between the two sexes. Moreover, there was a significant correlation between body weight and fecal fat and chymotrypsin excretion. The results obtained contribute to the evaluation of small intestine functionality, especially in relation to some diseases, as malabsorption, maldigestion and steatorrhea in the dog.  相似文献   
69.
70.
The aim of this study was investigate the effect of growing associated with different gender on circulating total and free iodothyronine concentrations during the first 13 mo of age in foals. In addition, we investigated the evolution of circulating concentrations of thyroid hormones during the first 3 d of weaning. Blood was collected from 13 clinically healthy Thoroughbred foals every month. All foals were weaned at the 4 mo and blood samples were taken also at 24, 48 and 72 h after weaning. The results obtained showed growing effects for tri-iodothyronine (T3), thyroxine (T4), free tri-iodothyronine (fT3) and free thyroxine (fT4) values (P < .001).

Serum T3 concentrations averaged respectively 2.89 and 0.29 nmol/L at 7 and 9 mo. Serum T4 concentrations averaged respectively 100.17 and 21.77 nmol/L at 1 and at 10 mo. Serum fT3 concentrations averaged respectively 6.96 and 1.50 pmol/L at 1 and 4 mo. Serum fT4 concentrations averaged respectively 31.40 and 4.93 pmol/L at 1 and 9 mo. Significant correlations between T3, T4, fT3 and fT4 with body weight (BW) and between T3, T4 and fT4 with age were observed.

Weaning effects (P < .001) were shown for T3 and fT4 levels. No differences (P > .05) in T4 and fT3 levels were observed over the 3-day period. Gender effects (P < .001) were shown for T3, T4, fT3, and fT4 levels. Significant correlations between T4 and fT4 with BW and age were observed in colts and fillies. T3 concentrations were correlated with age only in colts and fT3 with BW only in colts. The results obtained seem to lend support to the recognized effects of growing and weaning in modulating the thyroid function of Thoroughbred foals. In fact, significant and differentiated effects of growing and weaning on total and free iodothyronine levels have been demonstrated.  相似文献   

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