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排序方式: 共有2204条查询结果,搜索用时 265 毫秒
1.
Revierförfter von Mühlen zu Solitude 《European Journal of Forest Research》1868,12(1):340-342
Ohne Zusammenfassung
Bergleiche Auguftheft diefer Bl?tter, in melchem gleichfalls auf die Wichtigfeit diefes Qegenftandes hingemiefen murde. Die
Red. 相似文献
2.
In a large pig breeding herd with high prevalence of post-parturient diseases of the sows, weaned sows of different parity groups with (n = 663) or without (n = 1125) recidiving mastitis metritis agalactia (MMA) in their previous history were subjected to ultrasonography. A total of 114 of 663 sows with recidiving MMA in their previous history and with ultrasonographic visible mammary gland changes, and 157 of sows without recidiving MMA in their previous history were culled and subjected to gross pathological and bacteriological examination of their mammary glands. The sows having suffered MMA had more (p < 0.001) hyperechogenic images in their mammary glands compared with the sow having suffered no recidiving MMA. Abdominal glands were more (p < 0.01) prone to pathological changes compared with the pectoral ones. Sows of high parity had more hyperechogenic images and gross pathological changes in their mammary glands compared with the sows of low parity. 相似文献
3.
A. Lindner Dr med vet l; P. von Wittke Dr. med vet; M. Schmald J. Kusserow H. Sommer Dr habil Dr med vet 《Journal of Equine Veterinary Science》1992,12(1)
Lactate kinetics in whole blood of horses was investigated after exercise of differing velocities and duration. The following categories of exercise were used: A: <11 m/second and >180 seconds (n=35), B: >11 m/second and <180 seconds (n=17) and C: <11 m/second and <180 s (n=10). The mean peak lactate concentration determined in horses in category A was 4.49 ± 2.21 mmol/1, in B, 16.32 ± 4.81 mmoVl and in C, 4.58 ± 1.59 mmol/l. While the maximum lactate concentrations in categories A and C were always found immediately after the exercise, the peaks in category B were measured between the first and tenth minute after exercise. Mean lactate concentrations measured at 2-minute intervals after bouts of category-B exercise tended to stabilize 3 to 10 minutes after exercise; however, mean lactate concentrations measured during the intervals before and after the peak value differed significantly. The lactate concentration returned to pre-exercise levels within 20 minutes after exercise bouts of category C, but remained above pre-exercise levels up to 60 minutes after bouts of category-A and -B exercise. It was concluded that, for an evaluation of lactate data after intensive anaerobic exercise, sequential blood sampling at 2-minute intervals for a period of up to 12 minutes after exercise is necessary. Less frequent sampling may be a reason for the often described irreproducibility of lactate concentrations in horses. After aerobic or mild anaerobic exercise, one sample is sufficient, but it has to be taken as soon as possible after exercise. 相似文献
4.
H Adam G von Lengerken D Olthoff M Schwalbe M Wicke 《Archiv fuer experimentelle veterinaermedizin》1989,43(2):293-299
Membraneous phospholipids of subcellular structures were determined from the musculature of German Landrace pigs of the GDR, following exposure to halothane. Mating variants A (H+ male X H+ female), B (H+ male X H- female), and C (H- male X H+ female) were used for positive responders (MHS), while variants B, C, and D (H- male X H- female) were used for negative responders (MHN). Four phospholipid fractions were recorded from the muscle samples for mitochondria and microsomes (according to SR section). Differences between the MHS and MHN groups for the above fractions and without consideration of mating variants and genotype were not observed, although unambiguous responses were exhibited by all animals, either positive or negative to halothan. Significant differences with regard to the above phospholipid fractions were recordable only for variant A (MHS group) as compared to D (MHN), in other words, for the homozygous genotypes, once the above results had been rearranged within MHS and MHN along with different mating variants and genotypes. However, no unambiguous results were obtainable for the heterozygous genotypes of mating variants B and C. Possible underlying reasons are discussed in some detail. The results obtained from mating variants A and D are likely to confirm earlier findings and seem to suggest that the sarcoplasmic reticulum is the primary site of origin of susceptibility to halothane or malignant hyperthermia. 相似文献
5.
Dr. Erika von Winning 《Journal of pest science》1948,21(9):141-142
Ohne Zusammenfassung 相似文献
6.
Colitis cystica profunda in dogs has been diagnosed in one case only. The two own cases were characterized by repeated, partly bloody diarrhea, vomitus, and painful defecation. The disease was diagnosed by clinical examination and colonoscopy with the ensuing histological examination of biopsy specimens. The disease could be managed by administration of a diet, sulfasalazine and corticosteroids. 相似文献
7.
8.
Verbeylen Goedele De Bruyn Luc Adriaensen Frank Matthysen Erik 《Landscape Ecology》2003,18(8):791-805
In determining isolation effects in fragmented populations, the landscape matrix is not often considered. Usually simple distance
measures are used to quantify degree of isolation. We tested the effect of the matrix on the presence of red squirrels in
354 wooded patches in the Brussels Region, by comparing several isolation measures. These were 1) distance to the nearest
source patch, 2) the Hanski-measure (a combination of distance to and size of all possible sources), 3) effective distances
calculated from different least cost models using the ArcView grid extension ‘Cost Distance’ (a combination of distance and
resistance of the landscape, with different resistances for different landscape types) and 4) some combinations of the Hanski-measure
and the effective distances. Size and quality of the target patches were always included in the tests of the predictive power
of different isolation measures on squirrel presence/absence. All variables examined (patch size, quality and isolation) significantly
influenced squirrel presence. Models using the effective distances gave the best results. Models including the Hanski-measure
improved significantly when Euclidean distance was replaced by effective distance, showing that parameterisation of matrix
resistance added significant additional explanatory power when modelling squirrel presence.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
Kim M. Plummer Sarah J. Clark Lana M. Ellis Ashwini Loganathan Taha H. Al-Samarrai Erik H.A. Rikkerink Patrick A. Sullivan Matthew D. Templeton Peter C. Farley 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(3):265-274
Peptidases have been implicated in the pathogenicity of fungi that cause disease in plants. Expression of the secreted aspartic peptidase gene (gcsap), of a Glomerella cingulata isolate pathogenic on apples, is induced during appressorium formation. To determine whether the secreted aspartic peptidase (GcSAP) is essential to pathogenicity, gcsap was disrupted using a vector containing a 637 bp fragment of genomic DNA that encodes the sequence spanning the two active site aspartic acid (Asp) residues. To ensure that the truncated gcsap gene products could not have residual peptidase activity the codons for the active site residues Asp112 and Asp297 were both mutated to histidine residues. Both PCR and Southern analysis confirmed disruption of gcsap. Neither gcsap mRNA nor GcSAP activity was detected in the disruption mutant. Pathogenicity tests on fruit from three apple cultivars showed that GcSAP was not required for pathogenicity. The disruption mutant grew on medium containing protein as the sole source of nitrogen because G. cingulata secretes a previously undetected peptidase(s). A serine peptidase that had a pH optimum between pH 7.0 and 8.0 and a K
m of 0.25 mM for the synthetic substrate succinyl-Ala–Ala–Pro–Phe-p-nitroanilide was identified. 相似文献
10.
Safety of standardized Macleaya cordata extract in an eighty‐four‐day dietary study in dairy cows 下载免费PDF全文
W. Wang L. C. Dolan S. von Alvensleben M. Morlacchini G. Fusconi 《Journal of animal physiology and animal nutrition》2018,102(1):e61-e68
The objective of this study was to evaluate the safety of a standardized Macleaya cordata Extract Product (MCEP) containing the quaternary benzophenanthridine alkaloids, sanguinarine and chelerythrine, when fed to dairy cows. Thirty‐six dairy cows were randomized into three groups with twelve cows/treatment in two replica pens for each treatment group: control (C) without MCEP added to feed, treatment 1 (SANG‐1000) with MCEP added to feed at 1,000 mg/animal/day (1.5 mg/kg bw/day) and treatment 2 (SANG‐10000) with MCEP added to feed at 10,000 mg/animal/day (15.5 mg MCEP/kg bw/day). After two weeks of acclimation, animals were observed for an 84‐day experimental period, with body weight, feed intake and milk production measured daily. Milk composition was analysed every two weeks. Haematological analyses were performed on Day 0 and Day 84, and clinical chemistry analyses were performed on Day 84 of the study. There was no statistically significant difference (p > .10) among the three groups on body condition score, milk production or milk composition over the study period. There were no significant differences in body weight gain or feed consumption among the three groups. Animals in the SANG‐10000 group had significantly higher mean corpuscular volume (MCV) than the C group (p < .1) and lower mean corpuscular haemoglobin concentration (MCHC) than the SANG‐1000 group (p < .1). Concentrations of sanguinarine and chelerythrine in milk samples collected on Day 84 were below the detection limit (LOD) as measured by high‐performance liquid chromatography‐mass spectrometry (HPLC‐MS/MS). In conclusion, this study presents compelling data supporting the hypothesis that the test product MCEP, when included in the TMR at up to 10,000 mg/animal/day (15.5 mg MCEP/kg bw/day), is well tolerated by dairy cows. 相似文献