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81.
Kerkmann A Ganter M Frase R Ostmeier M Hewicker-Trautwein M Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(9-10):413-421
In three flocks, 13 pure- and 1 crossbred German black headed mutton lambs were ascertained which had clinical signs of epidermolysis bullosa (EB). The three farmers reported of further 20 affected lambs with similar signs in their flocks in the past lambing seasons. The affected lambs were progeny of six rams and 17 ewes. Two rams and six ewes with affected offspring from two farms were used for a breeding trial. In the course of these experimental matings, 21 lambs were born, six of which were affected by EB. All lambs born in this trial underwent clinical and haematological examination and all the affected lambs had to be euthanised due to severe and progressing clinical symptoms. Clinical examinations in 20 affected lambs revealed shedding of claw horn, erosions and ulcers of skin and mucous membranes. Histopathology showed subepidermal splitting and blistering with intact basal keratinocytes. These findings together with the premature death of affected lambs within the first two months of life made a Herlitz type of junctional EB most likely. The results of the test matings demonstrated the genetic transmission and indicated an autosomal recessive mode of inheritance for this lethal condition. 相似文献
82.
Zdeňka Svobodová Jana Máchová Hana Kroupová Miriam Smutná Ladislav Groch 《Aquaculture International》2007,15(3-4):277-286
Three case studies of ammonia autointoxication of the common carp (Cyprinus carpio L.) are described. In the first case, carp yearlings with a full digestive tract were transferred during the growing period
from pond water (22°C) to tap water (17°C). In the second case, marketable carp were transferred from the fishing ground of
a pond (18°C) to a storage pond (10–12°C). Harvest was performed in late September when the fish were still ingesting natural
feed. In the third case, marketable carp after storage for 1 month were transferred to storage ponds with markedly lower water
temperature. Stress because of harvest and handling also occurred in this case. In all cases, highly increased concentrations
of ammonia were found in the blood plasma of the fish (mean ± SD 1760 ± 350 μmol L−1 in the first case, 870 ± 540 μmol L−1 in the second case, and 880 ± 150 μmol L−1 in the third case). Highly congested, dark-red coloured, oedematous gills were observed for all specimens. We can avoid similar
cases of ammonia autointoxication by protection of fish from sudden changes of temperature during rearing, harvesting, and
handling. 相似文献
83.
Aranzazu Hernández-Andrés Miriam Pérez-Mateos Pilar Montero Maria Del Carmen Gómez-Guillén 《Fisheries Science》2008,74(4):899-910
ABSTRACT: High-pressure technology is used as an alternative to heat processing because of its inactivating effect on microorganisms and enzymes. However, it can also alter the structure of other muscle proteins. The present study compares the effects of high pressure (300 MPa, 7°C, 20 min) on the proteolytic degradation and alterations in the myofibrillar proteins of sardine and blue whiting muscle. Also, muscle homogenates and enzyme extracts were pressurized in order to evaluate the high-pressure effects on unprotected proteolytic enzymes outside the whole muscle structure. Peak proteolytic activity was found to occur at 55°C in both species. The peak activity pH was pH 3 for the sardine and pH 8 for the blue whiting; the main enzyme families being aspartic proteases in the former and alkaline serine proteases in the latter. Pressurization lowered activity levels at the peak activity pH and temperature in the fish muscle (by 30.8% in the sardine and by 9.5% in the blue whiting) and also slightly in the enzyme extracts (by 16.8% in the sardine and by 19.4% in the blue whiting). The electrophoretic profiles disclosed higher protein degradation in the pressurized muscle. Overall, the observed changes in proteolytic activity can be attributed not only to the effect of high pressure on the enzymes, but also and mainly, to the effect on other muscle proteins. 相似文献
84.
M. Wysoki G. Forer E. Dunkelblum Miriam Harel Polina Fraistat Devora Gordon L. Anshelevich M. Kehat M. Kehat L. Anshelevich Devora Gordon Miriam Harel E. Dunkelblum L. Zilberg A. Rubin A. Shani Ada Rafaeli Miriam Altstein Oma Ben-Aziz Irit Schafler I. Seltzer C. Gilon A. Hefetz Tamar Katzav Victoria Soroker Ali R. Harari 《Phytoparasitica》1998,26(2):175-181
85.
Yehudith Birk Miriam Waldman 《Plant foods for human nutrition (Dordrecht, Netherlands)》1965,12(2):199-209
Summary A comparative study has been carried out on amylase, urease and trypsin-inhibiting activities in the soybean varieties Adams, Harosoy and Lincoln and in soybean plant material of Harosoy. No significant quantitative difference was found between these activities in the three varieties. Two pH optima, at 5.5 and at 6.4 were found for amylase activity from all three varieties of soybeans. Although the temperature of 60° was most favourable for Adams-, Harosoy-and Lincoln-amylase, the latter lost almost all its activity at 70° whereas that of Adams remained constant.No urease and trypsin-inhibiting activities and only slight amylase activity could be detected in the leaves, stems and empty pods of the soybean plant. Young seeds (three weeks after setting) were compared, on the basis of dry weight, to mature seeds and were found to contain 50% of the trypsin inhibiting activity, 34% of the amylase and only 3% of the urease of the latter.
with 3 figs. 相似文献
Zusammenfassung Eine vergleichende Studie wurde durchgeführt über Amylase-, Urease- und Trypsin-hemmende Wirkung der Sojabohnen-Sorten Adams, Harosoy und Lincoln sowie in Sojabohnenpflanzen der Sorte Harosoy. Keine mengenmäßig-signifikanten Unterschiede in der Wirkung fanden sich bei den drei Sorten. Zwei pH-Optima ergaben sich für die Amylase-Aktivität der drei Sojabohnen-Sorten bei 5,5 und 6,4. Obwohl die Temperatur von 60° sehr günstig für die Amylase der Sorten Adams, Harosoy und Lincoln war, verlor die Amylase der letztgenannten Sorte fast ihre gesamte Wirksamkeit bei 70°, während die der Sorte Adams dabei konstant blieb.Keine Urease- und Trypsin-hemmende Wirkung und eine nur leichte Amylase-Aktivität konnte in den Blättern, Sproßachsen und in den leeren Hülsen der Sojabohnen-Pflanze nachgewiesen werden. Junge Samen (drei Wochen nach der Aussaat) wurden auf Trockengewichtsbasis mit reifen Samen verglichen. Es wurde bei den jungen Samen — im Vergleich zu den reifen — eine nur 50%ige Trypsin-hemmende Wirkung, eine 34%ige der Amylase und eine nur 3%ige der Urease ermittelt.
Resumen Se ha efectuado un estudio comparativo sobre las actividades de la amilasa, la ureasa y el inhibidor de la tripsina en las variedades de porotos de soya Adams, Harosoy y Lincoln, así como en algunas partes vegetativas de la variedad Harosoy. No se encontraron ningunas diferencias cuantitativas entre las actividades de estas variedades. Se encontraron dos valores optimales del pH, 5.5 y 6.4, para la amilasa de todas las tres variedades de porotos de soya. Aunque la temperatura más favorable para la amilasa de las variedades Adams, Harosoy y Lincoln fuera 60°, esta última perdió casi toda su actividad a 70°, mientras que la actividad de la variedad Adams se quedó sin cambiar.No se pudo demostrar la presencia de ureasa y actividad inhibidora de la tripsina en las hojas, los tallos y las cápsulas vacías de las plantas de soya, y se encontró solamante una ligera actividad de amilasa en estas partes vegetativas. Se compararon, en base seca, semillas nuevas (a las tres semanas de formarse) con semillas maduras. Se encontró que las primeras exhibieron 50% de la actividad inhibidora de la tripsina, 34% de la actividad de amilasa y solo 3% de la actividad de ureasa, en comparación con las actividades de las semillas maduras.
Resumé Une étude comparative a été faite sur les activités de l'amylase, l'uréase et l'activité inhibitrice de la trypsine, dans les variétés de fèves de soya: Adams, Harosoy et Lincoln ainsi que sur différents stades de l'appareil végatatif du soya Harosoy. Aucune différence quantitative, significative, ne fut trouvée entre les activités dans les trois variétés. Deux pH optima à 5.5 et à 6.4 furent trouvés pour l'activité de l'amylase de toutes les trois variétés de fèves de soya. Bien que la témperature de 60° fut la plus favorable pour l'amylase de Adams, Harosoy et Lincoln, l'amylase de ces 2 derniers perdit presque toute son activité à 70° tandis que l'amylase dAdams resta constante.Ni activité d'urease, ni activité inhibitrice de trypsine ainsi que très peu d'amylase ne furent observés dans les feuilles, tiges et gousses vides de la plante soya. De jeunes semences (trois semaines après la fécondation) furent comparées, sur la base du poids sec, à des semences adultes et furent trouvées contenir 50% de l'activité inhibitrice de la trypsine, 34% de l'amylase et rien que 3% de l'uréase par rapport aux graines adultes.
with 3 figs. 相似文献
86.
Increase in phosphorylase activity during cold-induced sugar accumulation in potato tubers 总被引:2,自引:1,他引:2
Pieternel A. M. Claassen Miriam A. W. Budde Martha H. Van Calker 《Potato Research》1993,36(3):205-217
Summary The accumulation of reducing sugars, sucrose and hexose phosphates in cv. Bintje and genotype KW77-2916 during storage at
2, 4, or 8°C was studied in relation to several catalytic activities. Bintje tubers accumulated sugars during storage at 2
or 4°C, whereas KW77-2916 showed reduced cold-sweetening at 2°C. The increase in glucose 6-phosphate and sucrose occurred
concurrently and preceded the increase in reducing sugar concentration. Phosphorylase activity showed a strong interaction
with temperature, storage duration and sugar accumulation in both genotypes. Invertase activity increased in Bintje concomitantly
with the increase in reducing sugars, but this effect was less obvious in KW77-2916. The activities of other glycolytic and
Krebs cycle enzymes showed no obvious correlation with sugar accumulation. It is suggested that the increase in phosphorylase
activity acts as a triggering event in the sweetening of potato tubers during cold storage. 相似文献
87.
Martin Venturas Salvia García Álvarez Miriam Fajardo Alcántara Carmen Collada Luis Gil 《European Journal of Forest Research》2013,132(1):107-120
Species selection for reforestations can be challenging in habitat protection zones, especially in human transformed landscapes, where nativeness of some species is not easily determined and yet is crucial for knowing whether a species can be used or not. We try to determine whether Pinus uncinata Ramond ex DC was present in the Cantabrian Range (Spain) and whether it could have disappeared recently due to anthropogenic causes. Plant morphology and needle anatomy were characterized in Pinus sylvestris L. and P. uncinata 2-year-old seedlings. An analysis of variance was used for selecting morphological markers capable of discriminating both species. These markers permit the comparison of seedlings coming from the highest zone of Puebla de Lillo relict pinewood (Cantabrian Range) with reference material from Castillo de Vinuesa (Iberian Range). This comparison was firstly made with two multivariate methods, a principal component analysis and a multivariate discriminant analysis. Subsequently, this was corroborated with the detection of a species-specific chloroplast DNA marker. The differences found between both species reflect the better adaptation of P. uncinata to typical highland environment. Several Puebla de Lillo seedlings had P. uncinata type morphology and haplotype, suggesting the presence of this species in the Cantabrian Range until recently. This discovery changes the current interpretation of the zone’s vegetation, enhancing the natural presence of highland open pinewoods. However, human activities (fire and livestock grazing) have driven them to extinction and have favoured the contemporary expansion of heathlands. Based on this P. uncinata case, we discuss how local extinctions can affect management and conservation policies negatively. 相似文献
88.
Diamond Miriam Ganapathy Murali Peterson Steve Mach Carl 《Water, air, and soil pollution》2000,117(1-4):133-156
The Lahontan Reservoir in western Nevada has among the highest mercury (Hg) concentrations recorded in water, sediments and biota. The QWASI fugacity/aquivalence multispecies model was applied to examine Hg dynamics through a steady-state analysis of high loading conditions. The analysis indicated that the Carson River supplies most Hg in the water and upper sediments, with minimal inputs from the atmosphere and the Truckee Canal. Model estimates suggest that more than 90% of Hg entering the system from the Carson River at high flow is retained in the sediment of the reservoir, with export removing the remainder. Losses due to volatilization are negligible. The amount of methylmercury (MeHg) in the reservoir can be accounted for by inputs from the Carson River with minimal methylation occurring in the reservoir. The lack of species conversion and high retention rate appear to be due to the unreactive mineralogy of particulate Hg. Thus, we suggest that Hg dynamics are similar to that of other highly particle-reactive metals where fate is determined by particle movement. Finally, model results suggest an additional source of Hg to the system, which we hypothesize is from deep contaminated sediment that enters the system through sediment mixing caused by seasonal wet and dry cycles and sediment resuspension. 相似文献
89.
Miriam S Martin Michael D Kleinhenz Abbie V Viscardi Andrew K Curtis Blaine T Johnson Shawnee R Montgomery Maria E Lou Johann F Coetzee 《Journal of animal science》2022,100(1)
Castration is a routine procedure performed on beef and dairy operations in the United States. All methods of castration cause behavioral, physiologic, and neuroendocrine changes associated with pain. The American Veterinary Medical Association and the American Association of Bovine Practitioners recommend that anesthesia and analgesia be administered during castration. The objective of this study was to evaluate the effectiveness of bupivacaine liposome suspension, a novel, long-acting, local anesthetic formulation administered as a nerve block at castration. The authors chose to investigate this novel formulation as an alternative to the current industry standards using lidocaine nerve blocks alone or in combination with meloxicam. Thirty male Holstein calves, 16 to 20 wk of age, were enrolled and randomly assigned to one of the four treatment groups prior to surgical castration: 1) bupivacaine liposome suspension block + oral placebo (BUP), 2) lidocaine block + oral placebo (LID), 3) lidocaine block + oral meloxicam (1 mg/kg) (LID + MEL), and 4) saline block + oral placebo (CON). Biomarkers were collected at −24 h and from 0 to 120 h post-castration and included infrared thermography, pressure mat gait analysis, chute defense and behavior scoring (pain and activity), and blood sampling for serum cortisol and prostaglandin E2 metabolites (PGEMs). Responses were analyzed using repeated measures, with calf nested in treatment as a random effect, and treatment, time, and their interaction designated as fixed effects. The results from pressure mat gait analysis show that the CON had a shorter front limb stance time from baseline (−8.73%; 95% confidence interval [CI]: −24.84% to 7.37%) compared with BUP and LID + MEL (>5.70%; 95% CI: −22.91% to 23.79%) (P < 0.03). The CON tended to have an increase in front limb force from baseline (6.31%; 95% CI: −1.79% to 14.41%) compared with BUP, LID, and LID + MEL (<−5.06%; 95% CI: −14.22% to 0.95%) (P < 0.04). The CON displayed higher counts of hunched standing (2.00; 95% CI: 1.68 to 2.32) compared with LID + MEL (1.43; 95% CI: 1.13 to 1.72) (P = 0.05). The CON had higher cortisol concentrations at 24 h (7.70 ng/mL; 95% CI: 1.52 to 13.87 ng/mL) relative to BUP (3.11 ng/mL; 95% CI: −2.56 to 8.79 ng/mL) (P = 0.002). At 4 and 24 h, LID + MEL had lower PGEM concentrations from baseline (−32.42% and −47.84%; 95% CI: −78.45% to −1.80%) compared with CON (27.86% and 47.63%; 95% CI: 7.49% to 82.98%) (P < 0.02). The administration of bupivacaine liposome suspension as a local anesthetic block at the time of castration was as effective at controlling pain as a multimodal approach of lidocaine and meloxicam. 相似文献
90.
Miriam Kleiter Dr. Med. Vet. David E. Malarkey DVM PhD David E. Ruslander DVM Donald E. Thrall DVM PhD 《Veterinary radiology & ultrasound》2004,45(3):255-260
Cyclooxygenase-2 (COX-2) is an enzyme upregulated in some human and animal tumors. Enzymatic products are associated with tumorigenic activities. Given the poor response of canine nasal tumors to radiation, we considered the possibility that some of this resistance may be associated with COX-2 expression. To test this, 21 formalin-fixed, paraffin-embedded, and archived biopsy samples from canine epithelial nasal tumors were analyzed for COX-2 expression using immunohistochemistry. The biopsies were collected from dogs prior to radiation therapy. COX-2 expression was present in 17 of 21 (81%) tumors. The expression was observed in several different tumor types, including nasal carcinomas, adenocarcinomas, and squamous cell carcinomas. Samples from five control dogs without nasal neoplasia were also analyzed for COX-2 staining. These specimens were characterized by varying degrees of lymphoplasmacytic rhinitis with scattered regions of COX-2 positive respiratory epithelial and stromal cells. Whether the intensity and distribution of COX-2 expression in nasal tumors can be used as a prognostic marker requires further investigation. A combination therapy of irradiation and a selective COX-2 inhibitor appears worthy of clinical investigation in the treatment of canine epithelial nasal tumors. 相似文献