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1.
H Herrmann 《Archiv fuer experimentelle veterinaermedizin》1978,32(4):489-494
Reported is a microprocess of enzyme immune assay in which slipformed air pockets of polyvinylchloride (PVC), as used in the pharmaceutical industry, are used as carriers of antigens or antibody. Two methods, the anti-globulin and the double-antibody methods, are based on antibody which had been coupled with alkaline phosphatase. Tests in which various sub-types of influenza virus were used have shown the double-antibody method to be a sensitive technique which can be successfully used in the differentiation of envelope antigens. 相似文献
2.
H Waibl J Herrmann J Rehage P Lorenzi G Constantinescu 《DTW. Deutsche tier?rztliche Wochenschrift》2001,108(6):261-263
A relatively thick (diameter approximately 2 mm), ropelike (length ca. 20 mm) and elastic "Vinculum tendinis" connects--within the fetlock tendon sheath--the dorsal side of the deep digital flexor tendon with the dorsal part of the Manica flexoria (the communicating band of the Musculus interosseous medius to the superficial digital flexor tendon). The extensive fetlock tendon sheath can be involved in diseases such as aseptic and septic inflammations. Spreading of these inflammations makes in some of these cases the partial resection of the tendon of the deep digital flexor muscle and the cutting of these Vincula necessary. The results of this contribution, collected from 60 hindlimbs of adult bovines show variations in number, length, diameter and extent and the inner structure with blood vessels and nerves. 相似文献
3.
4.
C Mohr L D?hner B Herrmann H Herrmann 《Archiv fuer experimentelle veterinaermedizin》1978,32(4):495-500
Matrix protein is known as a type-specific structural protein of influenza viruses. An attempt has been made to find out whether or not strain-specific components could be detected from matrix protein, in addition to its type-specific antigen determinants. The technique of enzyme immune assay was chosen as the optional method to differentiate between matrix proteins of various influenza-A viruses. Antigen titration was undertaken of several matrix proteins, using two specific anti-matrix-protein sera in each case. Information regarding serological relationships between the tested matrix proteins of various influenza-A viruses was obtained from a quotient between the titres of one antigen, on the one hand, and the two anti-matrix-protein sera used in titration, on the other. Two matrix protein sub-types were established in the context of the influenza-A viruses tested. Sub-type M1 was attributable to older strains (A/PR/8 and A/FM/1), whereas the matrix protein of sub-type M2 was found to be present in more recent strains (A/Hongkong and A/Port Chalmers). 相似文献
5.
6.
Application of the Soil and Water Assessment Tool (SWAT) to predict the impact of alternative management practices on water quality and quantity 总被引:10,自引:0,他引:10
Alternative land management practices such as conservation or no-tillage, contour farming, terraces, and buffer strips are increasingly used to reduce nonpoint source and water pollution resulting from agricultural activities. Models are useful tools to investigate effects of such management practice alternatives on the watershed level. However, there is a lack of knowledge about the sensitivity of such models to parameters used to represent these conservation practices. Knowledge about the sensitivity to these parameters would help models better simulate the effects of land management. Hence, this paper presents in the first step a sensitivity analysis for conservation management parameters (specifically tillage depth, mechanical soil mixing efficiency, biological soil mixing efficiency, curve number, Manning's roughness coefficient for overland flow, USLE support practice factor, and filter strip width) in the Soil and Water Assessment Tool (SWAT). With this analysis we aimed to improve model parameterisation and calibration efficiency. In contrast to less sensitive parameters such as tillage depth and mixing efficiency we parameterised sensitive parameters such as curve number values in detail.In the second step the analysis consisted of varying management practices (conventional tillage, conservation tillage, and no-tillage) for different crops (spring barley, winter barley, and sugar beet) and varying operation dates. Results showed that the model is very sensitive to applied crop rotations and in some cases even to small variations of management practices. But the different settings do not have the same sensitivity. Duration of vegetation period and soil cover over time was most sensitive followed by soil cover characteristics of applied crops. 相似文献
7.
K Krawielitzki T Zebrowska R Schadereit J Kowalczyk U Hennig J Wünsche U Herrmann 《Archives of Animal Nutrition》1990,40(1-2):25-37
In an experiment with 3 pigs (initial live weight 30 kg, each fitted with 2 re-entrant fistulas in duodenum and ileum, one labelled with 15N), the duodenal and ileum digesta was exchanged. The N and 15N contents were estimated in faeces, urine, duodenal and ileum digesta of all experimental animals as well as in special organs and in the contents of different tract sections. The 15N excess (15N') of N compounds secreted into the gut lumen was determined using the 15N' in pancreas, gut mucosa and TCA-soluble blood serum. From measuring the digesta passage through the 3 sections of the digestive tract: 1. mouth ... duodenum, 2. duodenum ... ileum, 3. ileum ... after (Krawielitzki et al., 1989) the absorption and secretion rates of nitrogen were calculated. Secretion into the 1st section amounted to 5.3 g N/d (= 15% of intake) and the absorption to approximately 1% of intake. In the 2nd section the corresponding dates were 8.9 resp. 38.6 g N/d (= 25 resp. 110% of N intake), and in the 3rd one 1.9 resp. 8.4 g N/d (= 5.6 resp. 24% of N intake). Total absorption amounted to 134% of N intake and the over all re-absorption of endogenous N compounds secreted into the gut lumen to about 90%. During the passage the amount of endogenous N (g/d) decreased from 5.3 at the duodenum to 3.8 at the ileum to 1.6 in the faeces, but the relative portion increased (13 resp. 35 resp. 39%). An incorporation into body proteins occurred only from N compounds absorbed in the 1st and in the 2nd section. N (or 15N) absorbed in the large intestine was almost quantitatively excreted by urine. The method of digesta exchange between cannulated labelled and unlabelled pigs seems to be a suitable method to estimate absorption and secretion of exogenous and endogenous N portions in various sections of the digestive tract. 相似文献
8.
Henrich Herrmann 《Forstwissenschaftliches Centralblatt》1915,37(2):51-60
Ohne Zusammenfassung 相似文献
9.
K Krawielitzki U Hennig T Zebrowska J Kowalczyk U Herrmann 《Archives of Animal Nutrition》1990,40(1-2):17-23
An experiment was carried out using pigs weighing approximately 30 kg. The animals were fitted with two re-entrant cannulas in duodenum and ileum. During a 5 day period the passage of digesta through duodenum and ileum as well as the excretion by urine and faeces was estimated, taking an aliquot of 5% for N analysis. Transit of digesta amounted to 12.4 ... 13.2. kg/d in the duodenum and 2.7 ... 3.6 kg/d in the ileum. The appertaining N passage rates were 36.8 ... 42.4 resp. 8.7 ... 11.2 g N/d, corresponding to 108 ... 120% and 27 ... 32% of the N intake. The transit rate of duodenal digesta was highest immediately after feeding (1.4 ... 1.5 kg/h), decreased thereafter strongly, reaching a second lower maximum of 0.85 ... 1.0 kg/h 2 ... 3 h after feeding and then going down to 0.3 ... 0.4 kg/h just before the next feeding. The daily mean value was about 500 g/h. Endogenous N content of duodenal digesta varied between 10% after feeding and 50% 6 ... 12 h after feeding, with an average of 18.1%. In contrast the endogenous N content of ileal digesta was relatively constant amounting about 42% during the whole day. These findings correspond with those found by other authors using other rations and other live weights of the pigs. They refer to a clear diurnal rhythm of digesta transit and to the enormous dynamics of absorption and secretion processes in the intestinal tract of pigs during digestion.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
The effects of weaning on beef calves of different ages were investigated. Forty male and 40 female calves were either weaned at 6 (W6, n = 40) or 8 (W8, n = 40) months of age. The vocalization activity and behaviors (feeding, lying and standing/walking) were observed during the first 3 days following weaning. Body weight was recorded at 6 and 8 months and 2 weeks following weaning. W6 animals vocalized more often than W8 calves and females more than males on day 1 (P < 0.05). The vocalization activity decreased at a higher rate in W8 than in W6 from days 1 to 3. On day 2, W6 calves spent less time lying and more standing/walking than W8 calves (P < 0.05). The behaviors did not differ between males and females. The average daily gain after weaning did not differ between weaning ages (P > 0.05), but W8 calves gained more from 6 to 8 months of age. In conclusion, weaning distress was more pronounced in W6 than in W8 calves. W8 calves also had a superior growth performance during 6 to 8 months of age. The effect of the calves' sex was less pronounced. Therefore, it is recommended to wean beef calves later than 6 months of age. 相似文献