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Zusammenfassung 49 röntgeninduzierte Mutanten der Wintergerstensorten Friedrichswerther Berg, Peragis Mittelfrühe II, Kleinwanzlebener 12 und Mahndorfer werden morphologisch beschrieben. Sie werden unter der Rangstufe Linie (auf dem gleichen Rang wie die Sorte), zusammengefaßt nach Hauptmerkmalen, in das morphologische System eingeordnet. Sie konnten 10 verschiedenen Varietäten der convar.hexastichon (L.) Alef. s. l. zugeordnet werden. Eine dieser Varietäten (var.semiaristatum, p. 240) stellt eine neue Merkmalskombination dar und wird beschrieben.Soweit bisher Kreuzungsanalysen vorliegen, werden Angaben über die Vererbung des Hauptmerkmals bei den einzelnen Mutanten gemacht; in der Regel liegen monogen rezessive Erbgänge vor. Drei verschiedene Ausprägungsgrade des Hauptmerkmals Grannen kurz und brüchig konnten auf ebenso viele Glieder einer Serie multipler Allele zurückgeführt werden (S. 235 ff). Sie werden wie folgt benannt:fragilis exigua ,fragilis mediocris ,fragilis distimeta . Nach der Dominanz geordnet, ergibt sich die ReiheFra > fra ex > fra med > fra dis .  相似文献   
54.
In two different dairy farms six calves exhibiting bilateral flexion of the fetlock joints in front or rear legs were born in 2000 to 2002. Four of the affected calves from the same farm were crossbred between German Holstein cows with red and white coat colour and a bull of the breed Limousin. The other two affected calves born on another farm were purebred German Holsteins with a black and white coat colour. The tests for BVD virus antigen and antibodies were negative in all affected calves. Three of the calves showed a lower selen and a higher glutamate dehydrogenase concentration in the analyses of blood metabolites. Two crossbred calves showed a degeneration of the liver with a progressive periportal fibrosis in a histological examination. In one calf an edema of astrocytes of the central nervous system was seen. The analysis of the pedigrees revealed for the four crossbred calves the Limousin bull as common ancestor and the mothers of the calves as relatives. For the affected purebred German Holstein calves also a sire was identified as a common ancestor. The pedigrees support inheritance through a monogenic autosomal recessive locus or more recessive gene loci with variable expressivity. However, the analysis could not clarify whether different gene loci are responsible for the congenital anomalies observed in the calves from the two farms and thus, the observed anomalies may be different genetic entities. Obvious environmental reasons were not found.  相似文献   
55.
The influence of contaminated hay [Cladosporium herbarum (CL) and Fusarium graminearum (FU), respectively] on fermentation and thiamine metabolism of bovine rumen content was investigated using the longterm rumen simulation technique (RUSITEC). Six investigation periods 25 days long each were carried out. A nine days feeding period with normal hay was followed by the testphase I (five days) with a mixture of normal and mouldy hay and testphase II (five days) with additive an 0.3 mg thiamine per reaction vessel. The last four days served as regeneration time with normal hay. The following marginal effects of mouldy hay on rumen fermentation patterns could be noted. A) During testphase I: cellulase activity: +10.0% (FU); alternation of the thiamine derivate pattern, but no effect on total thiamine content (CL, FU). B) During testphase II the results were more obvious: bacterial protein synthesis: -22.6% (CL), -24.4% (FU). Alternation of the fatty acid pattern: propionate (-7.30% FU), n-butyrate (-3.90% CL, +3.49% FU), n-valerate (-8.5% CH, FU). Cellulase activity: -17.0% (CL, FU). But no effect on total thiamine (CL, FU); alternation of the thiamine derivate pattern: more non phosphorylate thiamine. The noted effects on rumen fermentation and thiamine metabolism were not severe enough to be responsible for the development of a CCN.  相似文献   
56.
An animal model for interface tissue formation in cemented hip replacements   总被引:2,自引:0,他引:2  
OBJECTIVE: To create a model in sheep for investigation of early changes related to the formation of an interface membrane in hip prosthesis. STUDY DESIGN: Experimental study. ANIMALS: Twenty-four female adult Swiss Alpine sheep. METHODS: Sheep were divided into 2 groups of 12 for unilateral cemented total hip arthroplasty. In Group I, the prosthesis was fixed with retrograde cement gun injection to achieve a complete cement mantle, whereas in Group II a primary cement mantle defect was produced. Groups I and II were further divided into 2 sub-groups with study end points of 2 and 8.5 months after surgery. Radiographs were evaluated postoperatively and at euthanasia for migration of the femoral component and bone resorption. Histologic sections were evaluated semiquantitatively for changes in cell types and numbers, and bone reactions; and quantitatively for size of interface membrane and new bone formation. RESULTS: Radiographically, there tended to be an increase in bone resorption and periosteal bone formation throughout the femoral shaft in Group II compared with Group I, but this was only statistically significant at the region of the femoral neck (R5) at both time periods (P<.05). Semiquantitative histologic evaluation revealed significant increases (P<.05) in cellularity, numbers of fibroblasts, giant cells, macrophages, and mononuclear cells, in Group II primarily at 2 months after surgery. This was also true for interface membrane formation and bone remodeling. Quantitative data showed an increased in the size of the interface membrane and area of bone formation at 8.5 months in Group II. CONCLUSIONS: The cement defect model offered controlled and repeatable production of an interface membrane. The results suggest that a primary cement mantle defect could be a possible trigger for implant instability, eliciting a cascade of biomechanical and molecular events in bone tissue leading to aseptic loosening. CLINICAL RELEVANCE: The results show the effect of defects in the cement mantle in promoting interface membrane formation. Long-term and biochemical studies are required to evaluate the relevance of this interface membrane formation.  相似文献   
57.
The objective of this study was to analyse the heritabilitiy of the lactational incidence of displaced abomasum (DA) and the relationships of DA with milk production traits in German Holstein cows. Data were recorded between February 1999 and January 2000 in cooperation with five veterinary practitioners. Their veterinary practices were located in the northern part of Lower Saxony. The investigation included 160 dairy farms under the official milk-recording scheme with 9,315 cows. The lactational incidence of the left abomasal displacement amounted to 1.21%, and of the right abomasal displacement to 0.41%, respectively. The linear heritability estimates for the lactational incidences of left and right DA were h(2) = 0.05 +/- 0.012 and h(2) = 0.004 +/- 0.005, respectively. Using the Dempster-Lerner-transformation the corresponding heritabilities were h(2) = 0.53 and 0.09, respectively. Milk losses for the lactation when DA was diagnosed were significant and reached 1016 kg milk, 41 kg fat, 36 kg protein and 0.07% protein. Fat content significantly increased by 0.18%. The analysis could not show significant differences between cows diagnosed with DA and cows not diagnosed with DA in the 305-day milk production traits of the lactation preceding the diagnosis of DA. There was also no indication for an unequal distribution of breeding values for milk performance traits between cows with and without DA. The additive genetic correlations between 305-day milk performance and left DA were low. The results indicated that cows with a high milk production and superior breeding values for milk performance were not exposed to an increased risk for DA.  相似文献   
58.
This study evaluated the suitability of invA gene amplification by PCR as an effective means of detecting Salmonella species in pigs experimentally infected with S. Typhimurium DT104. A controlled infection study using 24 pigs was performed in order to compare efficacy, precision and detection rates of the invA-based PCR method originally described by Rahn, K. De Grandis, S.A., Clarke, R.C., McEwan, S.A., Galan, J.E., Ginocchio, C., Curtiss, R. 3rd, C.L. Gyles, (Mol. Cell. Probes 1992; 6: 271-279) as a new in-house invA-based PCR method for the specific detection of Salmonella spp. in pork and different tissue samples of slaughter pigs. Finally, PCR results were compared with culture detection rates obtained by isolation procedures following the ISO 6579:2000, the 'gold standard'. After slaughtering, 14 different tissue samples of each pig were investigated to verify the usefulness of the two invA-based PCR methods in different matrices of slaughter pigs. The results demonstrate that the application of the widely used invA-based primer pair (139 + 141) may result in questionable products if samples gained from selective enrichment in the Rappaport-Vassiliadis medium were investigated. These questionable products can lead to false-positive results, if no additional hybridization procedure is attached or if unspecialized persons use this method in routine laboratory practice. The newly developed in-house PCR method used is based on the 3'-prime region of invA, especially designed and harmonized for the detection of Salmonella in different matrices of slaughtered pigs after bacterial enriched broth culture. In this study, this PCR revealed no questionable products and, furthermore, the specificity of the amplificate could be tested by means of the restriction enzyme NdeI. In comparison with the culture detection procedure, the new PCR method has a sensitivity of 100% and a specificity of 96%. Thus, this method might be used as a meaningful tool in eliminating Salmonella-positive carcasses at slaughterhouse level and thus, keeping them out of the food chain.  相似文献   
59.
Human beings routinely help others to achieve their goals, even when the helper receives no immediate benefit and the person helped is a stranger. Such altruistic behaviors (toward non-kin) are extremely rare evolutionarily, with some theorists even proposing that they are uniquely human. Here we show that human children as young as 18 months of age (prelinguistic or just-linguistic) quite readily help others to achieve their goals in a variety of different situations. This requires both an understanding of others' goals and an altruistic motivation to help. In addition, we demonstrate similar though less robust skills and motivations in three young chimpanzees.  相似文献   
60.
Since 1990 the number of glanders outbreaks in race, military and pleasure horses in Asia and South America is steadily increasing. Glanders, which is eradicated in Western Europe, Australia and Northern America, is currently considered a re-emerging disease. Consequently, the disease may be introduced into glanders-free regions by subclinical carriers at any time. The causative agent of glanders, Burkholderia (B.) mallei, is highly contagious and leads to chronic disease in horses whereas in donkeys and mules the disease is acute and often fatal. Occurrence of the disease leads to international trading restrictions and infected animals immediately have to be culled and safely disposed off. In humans B. mallei infection results in a severe clinical course, and is fatal without appropriate therapy. Its pathogenicity makes B. mallei a potential biological agent that may be used in bioterroristic attacks. Due to the eradication of glanders in the second half of the last century, veterinarians in western European countries are no longer familiar with its clinical presentation in solipeds. Having these facts in mind, this review describes the epidemiology, clinical signs, pathology and the current eradication strategy of this interesting zoonosis. Pictures of imported endurance horses infected with glanders taken during an eradication campaign in Dubai, United Arab Emirates, in 2004 illustrate most typical clinical findings.  相似文献   
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