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101.
Cu deficiency — a potential factor in BSE? Recent data indicate that ”︁normal prions” contain copper as an antioxydative cofactor. In ”︁infective prions” Cu seems to be replaced by other trace metals. Cu deficiency symptoms of ruminants as described in the older literature are compared with the symptoms of bovine spongiform encephalopathy (BSE).  相似文献   
102.
103.
Experiments were conducted to assess protein solubility in .2% KOH as an indicator of soybean protein quality for chicks and pigs and to assess effects of particle size on protein solubility. As the particle size (micron) of soybean meal (SBM) increased, protein solubility (%) decreased (b = -.0206). In two 9-d chick trials, dehulled SBM (48% CP) was subjected to various autoclaving times and then fed as the sole source of dietary protein to young chicks. Increasing autoclaving times from 0 to 40 min at 120 degrees C resulted in a quadratic decrease in protein solubility. A broken-line model was fitted wherein gain:feed of chicks was plotted as a function of protein solubility. The analysis showed no reduction in feed efficiency with solubilities greater than 59 +/- 1.5% (mean +/- SEM). When solubility was below 59%, however, gain:feed decreased 1.5% for each 1% decrease in protein solubility. The third trial (13 d) was conducted with 7.5-kg pigs fed autoclaved SBM (44% CP) as the primary source of protein. Feed efficiency was significantly decreased when protein solubility was less than 66%. This study showed that protein solubility in KOH was a good index of in vivo soybean protein quality, and that it is important to standardize SBM particle size when applying the KOH assay.  相似文献   
104.
Zussamenfassung Alle untersuchten Zellwandpr?parate von isolierten Karottengeweben enthalten mehr oder weniger unl?slichen Stickstoff. Besonders hoch sind diese Stickstoffwerte in den Zellw?nden von Geweben, die auf kinetinhaltigen oder mit h?heren Auxinmengen versehenen N?hrmedien gewachsen waren. Relativ niedrige Stickstoffwerte erh?lt man dagegen in den Zellw?nden von Geweben auf Medien mit Fraktion G1. Das Problem der Anwesenheit von Proteinen und Nucleins?uren in den W?nden pflanzlicher Zellen wird anhand der Literatur diskutiert. Mit einem Ausblick auf die Kontrolle der Zellwandbildung durch die Zelle und den hierbei wirksam werdenden Informations-Rückkopplungs-Mechanismus schlie?t die Arbeit.
Summary All the tested cell wall preparations of isolated carrot tissues contain more or less insoluble nitrogen. These nitrogen values are particularly high in the cell walls of those tissues grown on media containing kinetin or higher amounts of auxin. On the contrary, relatively low nitrogen values are found in the cell walls of tissues cultured on media containing the fraction G1. The problem of the presence of proteins and nucleic acids inside the walls of plant cells is discussed in relation to results obtained by other authors. The paper concludes with a brief review of the control mechanism of cell wall formation by the cell itself and of the feed back of informations involved in it.

Résumé Toutes les préparations étudiées des parois cellulaires des tissus de carotte contiennent plus ou moins de l'azote insoluble. Particulièrement cette teneur en azote est très considérable dans les parois cellulaires des tissus cultivées sur des milieux contenants la cinétine ou des quantités d'auxines fort élevées. Contrairement on obtient des teneurs en azote relativement basses dans les parois cellulaires des tissus cultivées sur des milieux contenant la fraction G1. Le problème de la présence des protéines et des acides nucléiques dans les parois des cellules végétaux a été discuté suivant les résultats de la littérature. L'exposé est terminé par une revue de la régulation de la formation de la paroi cellulaire par la cellule elle-meme, et du mécanisme de couplage rétroactive de l'information.


(mit 1 Fig. )  相似文献   
105.
Isolation and molecular characterisation of equine rotaviruses from Germany   总被引:2,自引:0,他引:2  
A total of 26 rotavirus positive faecal samples of diarrhoeal foals, and 8 equine rotavirus isolates were examined. Viral RNA patterns were generated, G typing was performed by PCR, and a P[12]-specific DNA probe was developed for P typing. Furthermore, five equine rotavirus isolates were sequenced in the genomic regions coding for VP7 and part of VP4. Rotaviruses of genotype G3 P[12] were found in 22 faecal samples and G14 P[12] type could be found in 4 faecal samples. These findings confirm that in Germany G3 P[12] is the predominating type of equine rotaviruses.  相似文献   
106.
Tissue samples from lungs, pulmonary lymph nodes, large intestine, and uteri of 14 wild boar bagged at a seasonal hunt were examined for the presence of chlamydiae, mycobacteria and mycoplasmas. Nested PCR detected chlamydial DNA in 57.1% of the animals, predominantly in the lung. DNA sequencing identified Chlamydophila psittaci as the predominant species, but Chlamydophila abortus and Chlamydia suis were also encountered. Immunohistochemical staining of tissue sections confirmed the presence of typical chlamydial inclusions in lungs and uteri. While the role of Chlamydiaceae as pathogens in wild boar has yet to be established, the present findings revealed a possible wildlife reservoir of these bacteria.  相似文献   
107.
A suitable method in the routine veterinary practice for the quantitative determination of the glomerular filtration rate (GFR) in dogs and cats has not been available until to date. Therefore, we modified the known plasma clearance model (=P-CL). The resulting P-CLterminal was assessed concerning its diagnostic value. P-CL of exogenous creatinine (P-CLcrea) and of inulin were determined in dogs (n=12, Beagle, 6 months of age) and cats (n=11, Domestic Short Hair, 14 months of age). The marker substances were administered as a bolus injection. In fasted dogs, P-CLcrea was 84.3 +/- 14.85 ml/min/m2 after a creatinine dose of 2.4 g/m2. An electrolyte infusion during the clearance determination did not alter the resulting values (p>0.05). In fasted cats, P-CLcrea was 54.7 +/- 5.8 ml/min/m2 (creatinine dose 2.0 g/m2). The inulin clearance, determined at the same time, was 104.5 +/- 19.81 ml/min/m2. Feeding the cats just before and during the test increased P-CL of both markers significantly (p<0.05). In order to adapt the clearance method for diagnostic assessment of GFR in the small animal practice, we aimed at minimizing the number of required blood samples (3 instead of 7 or more) and introduced the modified exogenous creatinine clearance (P-CLterminal). These values determined were 108.4 +/- 20.81 ml/min/m2 in fasted dogs and 66.3 +/- 11.81 ml/min/m2 in fasted cats. An electrolyte infusion (dogs) and feeding (cats) had the same effect on P-CLterminal values as described above for P-CL. In conclusion,the modified exogenous creatinine clearance is a suitable renal function test for the early diagnosis of renal disease in dogs and cats presented in small animal practices.  相似文献   
108.
To enable us to handle a large number of oocytes at a given time and to have an increased throughput of cloned embryos, we attempted the Handmade cloning (HMC) technique, a zona-free method of bovine somatic cell nuclear transfer. Our objective was to study the developmental competence of the HMC derived embryos obtained using different types of somatic cells. A total of 6,874 cumulus-oocyte-complexes were used with either 7th or 11th passage fibroblasts (1st and 2nd groups, respectively), which were prepared from male animals, or granulosa cells (3rd group) as nuclei donors. The average cleavage rate was 65%, accompanied by a blastocyst rate of just 2% for the cleaved products and 5% for the >8-cell embryos, and there was no significant difference between the three groups. Out of 27 blastocysts recovered, 22 blastocysts were transferred to 22 recipients, resulting in two pregnancies. One pregnancy was lost after the fourth week while the other progressed to full term with the birth of a male calf. This first successful cloning of a male calf with the HMC technique in Europe indicates the successful adoption and establishment of this technique in our laboratory, and that this technique can be successful in producing viable embryos.  相似文献   
109.
The objective of this study was to evaluate the effect of supplementary antioxidants (AOX) and whey protein on the immune function health of puppies. Four groups of 10 puppies were fed a control and 3 different test foods (control + antioxidants (AOX), control + AOX + 1% whey protein, and a grocery brand (low AOX)) for 6 weeks. A standard vaccination protocol with a combination canine parvovirus (CPV) and distemper (CDV) vaccine was carried out at 2 and 4 weeks. The results showed that animals on high AOX foods had significantly increased titers, memory cells and serum E concentrations compared to the control and groc groups respectively.  相似文献   
110.
For molecular biological detection of Mycobacterium avium subsp. paratuberculosis (MAP), PCR methods with primers targeting different regions specific for MAP are used worldwide. However, some uncertainties exist concerning the specificity of certain target regions and the sensitivity. To identify the methods which are best suited for diagnostics, 8 single-round and 5 nested PCR systems including 12 different primer pairs based on IS900 (9 x), ISMav2 (1x), f57 (1x), and locus 255 (1x) sequences were compared regarding their analytical sensitivity and specificity under similar PCR conditions. Reference strains and field isolates of 17 Mycobacterium species and subspecies, 16 different non-mycobacterial bovine pathogens and commensals were included in this study. Single-round PCR resulted in a detection limit of 100 fg to 1 pg, and nested PCR in 10 fg or below. Depending on the specific primer sequences targeting IS900, false positive results occurred with one of the five single-round and two of the four nested PCR systems. This also applied to the single-round PCR based on ISMav2 and the nested PCR based on f57. A high number of non-specific products were primarily detected for the single-round PCR assay based on ISMav2, but also for a single-round PCR targeting the IS900 and the locus 255. In conclusion, stringent selection of IS900-specific primers ensures that IS900 remains a favourite target sequence for amplification of MAP specific loci. The studied PCR systems based on f57, and locus 255 can also be recommended. Revision of ISMav2 primers is necessary. Single-round PCR systems are very reliable. Nested PCR assays were occasionally disturbed by contaminations, thus bearing a risk for routine diagnostics.  相似文献   
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