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51.
Tight junctions (TJs) in inter-Sertoli junctional areas and epididymal epithelia build up the blood–testis barrier (BTB) and the blood–epididymal barrier (BEB), respectively. In this study, the expression of occludin, an integral member of the TJs, was examined in testis and different regions of epididymis of Lepus sinensis coreanus , an Korean wild rabbit species. In testis, intense occludin immunoreactivity was found in the basally located inter-Sertoli junctional area together with diffused immunoreactivity of occludin in the cytoplasm of Sertoli cells. It can be suggested that occludin is one of the robust elements of BTB in seminiferous tubules of rabbit testis. In proximal and distal caput epididymis, occludin immunoreactivity was found in the lateral as well as apical contacts of epithelial cells. In corpus epididymis, intense occludin immunoreactivity was found in the basolateral as well as apical contacts of epithelial cells together with cytoplasmic signal. In cauda epididymis, occludin immunoreactivity in luminal epithelia was relatively strong but largely found in the cytoplasm. This suggests that intriguing regulatory mechanisms differentially recruit occludin to the TJ in the different regions of epididymal epithelia. The differences in the subcellular localization as well as expression levels of occludin among the epididymal segments may reflect differential paracellular permeability of epithelia along the epididymal tubules and be correlated with sperm maturation in rabbit. In Western blot, a major form of occludin was MW 62 kDa together with small fragments of MW 34–39 kDa in testis and epididymis, suggesting the peptide cleavage of occludin. This is the first report on the molecular nature of TJs in a wild rabbit testis and epididymis.  相似文献   
52.
Objective To document an ovine disease attributed to the consumption of Lythrum hyssopifolia (lesser loosestrife). Procedures Historical and histological review of field and experimental cases. Results 1–20% mortality occurred in sheep flocks grazing paddocks where L. hyssopifolia was the predominant green vegetation. Well‐documented disease outbreaks occurred in summer on nine farms across Victoria between 1974 and 2002. Liver damage occurred in all nine outbreaks, with kidney damage in at least eight. Hepatocyte necrosis was usually zonal to midzonal (zone 2) in the liver samples from four farms and periacinar (zone 3) in those from three farms, but some livers showed only single‐cell necrosis. Multinucleate hepatocytes near necrotic areas were a feature in six cases. Proximal tubular epithelium appeared to be the primary renal target and brown granules were often present in renal tubules. Biochemical and histological evidence of liver and kidney damage was obtained from two sheep experimentally pen‐fed harvested L. hyssopifolia. Conclusion Chemicals in L. hyssopifolia are toxic to ovine hepatocytes and renal tubular epithelial cells.  相似文献   
53.
A 14-year-old Haflinger mare was presented with a wound on the right metatarsus which it had sustained 3 years earlier. The wound had never completely healed but had only recently become a problem. Over a period of several months, the wound became larger, produced a lot of exudate, and the horse became lame on the affected limb. Clinical examination and radiographs failed to reveal the cause of the deterioration. Histological evaluation of tissue removed during debridement of the wound revealed squamous cell carcinoma. Because the tumour had already invaded the bone, the prognosis was unfavourable and the horse was euthanised. Necropsy showed the tumour to have metastasised to the right inguinal area and the adjacent mammary gland.  相似文献   
54.
SUMMARY: Biochemical profiles, restriction endonuclease analysis (REA) and ribotyping were used to investigate Pasteurella multocida isolates from outbreaks of fowl cholera on 7 turkey farms in New South Wales. While only a single isolate was available from 5 of the farms, multiple isolates, 4 and 12 respectively, were available from the other 2 farms. The available field evidence suggested that 8 outbreaks had occurred with one farm suffering 2 outbreaks. The isolates obtained were all confirmed as Pasteurella multocida . Biochemical profiles allocated the isolates to 4 groups, 3 being variants of P multocida subsp multocida and the fourth being P multocida subsp septica . REA performed with Hpall established 7 groups. Ribotyping using the Hpall digests probed with the 16S rRNA operon of Haemophilus paragallinarum recognised the same 7 groups as REA. Unlike the biochemical profiles, both REA and ribotyping provided a fine subdivision that identified outbreaks as either related or unrelated. The REA and ribotyping patterns as well as biochemical profiles were stable for all isolates from the outbreaks in which multiple isolates were obtained from either the same bird or from different birds. REA and ribotyping were found to be superior to biotyping methods for the investigation of fowl cholera outbreaks.  相似文献   
55.
Zusammenfassung Die Untersuchung des Reifevorgangs bei Buchenfrüchten durch Verfolgung von Frischgewicht, Trockengewicht und Fettgehalt ergibt, da? der Reifeproze? erst Anfang bis Ende August beginnt und sechs bis acht Wochen dauert. Eine Beurteilung der Bucheckern auf Keimf?higkeit ist daher frühestens Mitte September m?glich. Auf Standorten mit Auflage von Moder oder Rohhumus wird die Entwicklung der Keimlinge durch eine Bodenbearbeitung nach dem Samenfall wesentlich gef?rdert; bew?hrt hat sich die Scheibenegge Rome TAH 14/28 und der Scheibenpflug TTS. Die schlechtere Keimlingsentwicklung bei fehlender Bodenbearbeitung wird auf eine Sch?digung der Keimpflanze beim Wurzelkontakt mit der obersten stark versauerten Mineralbodenschicht zurückgeführt. Zur F?rderung des Buchenaufschlags hat sich eine Düngung kurz vor oder nach dem Buchenaufschlag nicht bew?hrt; empfehlenswert scheinen dagegen Kalkungen 10 bis 30 Jahre vor Bestandesverjüngung.
Investigations regarding the natural regeneration of beech (Fagus silvatica)
Summary The ripening process of beech seeds as followed by the measurement of fresh weight, dry weight and fat content starts beginning to end of August and takes 6 to 8 weeks. A judgement of the germination ability is possible not earlier than mid of September. At sites with mor or raw humus the development of the seedlings can be improved substantially by soil cultivation. The unsatisfactory development of seedlings if soil cultivation is missing is caused by a damage of the seedling after beeing in root contact with the uppermost strongly acid mineral soil layer. A fertilization shortly before or after the seed fall has no positive effect on the development of seedlings; liming should be done 10 to 30 years before regeneration of the stand.
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56.
57.
A steer examined because of obstructive urolithiasis and urethral rupture underwent laser lithotripsy, using a chromium-thulium-holmium:yttrium-aluminum-garnet (Ho:YAG) laser inserted through an ischial urethrotomy. Procedures were performed with caudal epidural anesthesia. Six months after surgery, the urethra was patent with no clinical evidence of urethral stricture or fistula. Ischial urethrotomy provided rapid access to the bladder for catheterization and to the obstructive urolith for lithotripsy. Laser lithotripsy was a rapid and effective means of urolith removal in this steer.  相似文献   
58.
A femtosecond laser-based optical frequency synthesizer is referenced to an optical standard, and we use it to demonstrate the generation and control of the frequency of electromagnetic fields over 100 terahertz of bandwidth with fractional uncertainties approaching 1 part in 10(19). The reproducibility of this performance is verified by comparison of different types of femtosecond laser-based frequency synthesizers from three laboratories.  相似文献   
59.
Is there a genetic basis to growth in Atlantic cod?   总被引:4,自引:0,他引:4  
There is still much disagreement and debate about whether or not genetically based growth differences occur in Atlantic cod, and there is evidence on both sides. In this review, data on genetically based growth differences in cod will be presented to shed light on this hypothesis. Motivated by the hypothesis that growth patterns may reflect specific genotype adaptations, we review stock‐specific responses on growth. An example of genetically based differences between the population units at two spawning localities off south Iceland is discussed. Here, significant differences in growth performance of the different SypI genotypes were found. Also, the cod sampled at Loftstaðahraun displayed higher mean weight and length compared to the cod from Kantur indicating that these population units may display different life histories. Other studies have shown conflicting results depending on which side of the Atlantic the problem has been investigated. We propose that a common‐garden meta‐analysis with several cod stocks from both sides of the Atlantic is needed to give any reasonable answer to the question of genetically based growth differences. Until such studies have been conducted, it is premature to conclude one way or the other. In this review, we have not tried to quantify how large the environmental part of growth regulation versus the genetic part is, as this information is not available in the published literature on cod. Based on recent research on two flatfish species (turbot and Atlantic halibut), approximately 30% of growth variation is caused by genetical factors, but it remains to be seen if this is similar in cod. A fruitful way to continue this research might be to conduct controlled experiments, where performance (growth, food intake, feed conversion efficiency, feeding behaviour, etc.) and environmental factors (e.g. temperature, oxygen, photoperiod, predation risk, food availability) are studied simultaneously for different genotypes and different stocks.  相似文献   
60.
Summary Extraction of synthetic amino acids dissolved in water by means of electro-ultrafiltration (EUF) showed average recovery rates of about 75%. Higher losses were obtained, particularly with cysteine, methionine and NH4 4; the latter, probably being deprotonated at the cathode, may be lost in form of NH3. The EUF extracts of three arable and two forest soils were investigated for their N compounds. In the arable soils only about 3% of the total organic N extracted by EUF was free amino acids; about 23%–55% consisted of amino N (hydrolysable N) and the rest was non-hydrolysable N. The two forest soils contained higher amounts of EUF-extractable organic N compared with the arable soils. In the two forest soils the content of free amino-acid N amounted to 8% and 11% of the EUF organic N, and the proportion of hydrolysable N from total EUF-organic N was 41% and 46%. It is suggested that the amino-acid N and the hydrolysable N can be easily mineralized.  相似文献   
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