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We report the case of a bilateral and multilocular spermatocele and sperm granuloma in a dog that was vasectomized 5 years before. Clinical examination revealed scrotal dermatitis and benign prostatic hyperplasia. Orchiectomy was performed, and gross and histological examination showed testicular degeneration associated with epididymal sperm granuloma. In relation to this case, the literature about long-term effects of vasectomy in dogs has been reviewed. On the basis of these results, a preventive sonogram and physical assessment in prostate and other reproductive structures before vasectomy is recommended. 相似文献
23.
Oestrus Expression and Ovarian Function in Repeat Breeder Cows, Monitored by Ultrasonography and Progesterone Assay 总被引:1,自引:0,他引:1
Ovarian ultrasonography and plasma progesterone levels were monitored in 37 lactating Holstein cows with a history of repeat breeding; the data obtained were analysed in conjunction with clinical and behavioural signs, to identify the aetiology of the syndrome. Differences were detected between RBCs displaying apparently normal cycles and others with irregular cycles. There were also differences in heat expression; a large number of repeat breeder cows (RBCs, 50%) displayed delayed or silent oestrus. Ovarian disorders were common in RBCs, and included ovarian cysts, mistimed AI, subluteal progesterone levels, luteal dysfunction or ovulation defects. Both ultrasonography and plasma progesterone assays are useful tools for ascertaining the aetiology of the repeat breeder syndrome. 相似文献
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Diversity of boron-toxicity tolerance in lentil growth and yield 总被引:1,自引:0,他引:1
Boron (B) toxicity is increasingly being recognized as a problem in arid areas of West Asia, where lentil is widely grown. This study investigated whether or not: (1) phenotypic variation of B-toxicity tolerance exists at the seedling stage in lentil, (2) such variation persists to affect adult performance, and (3) there is geographical diversity in seedling tolerance. Four experiments were conducted in a greenhouse. Boric acid was added and mixed uniformly into the soil-mix to prepare high-B soil. Experiment I screened 77 lentil lines randomly selected from ICARDA's international nurseries. Visual growth scores and foliar B-toxicity symptom scores were taken 4–5 weeks after sowing, and used as an indicator for B-toxicity tolerance. In Experiments II and III, four selected lines were studied beyond the seedling stage. In Experiment IV, 231 lentil accessions from seven different countries/regions of the world were screened. There were highly significant differences between the 77 lines in B-toxicity tolerance at the seedling stage as indicated by their degree of B-toxicity symptom, and plant growth. The two tolerant and two sensitive selections from Experiment I showed diverse performance up to maturity as reflected by their differences in leaflet loss, dry mass reduction, and seed yield when grown in high-B soil. There were significant differences in B-toxicity tolerance between the 231 accessions. On average, accessions from Afghanistan were the most tolerant, followed by those from India, Iraq, Syria, Europe, Ethiopia, and Nepal. 相似文献
25.
Lucas RJ Hattar S Takao M Berson DM Foster RG Yau KW 《Science (New York, N.Y.)》2003,299(5604):245-247
In the mammalian retina, a small subset of retinal ganglion cells (RGCs) are intrinsically photosensitive, express the opsin-like protein melanopsin, and project to brain nuclei involved in non-image-forming visual functions such as pupillary light reflex and circadian photoentrainment. We report that in mice with the melanopsin gene ablated, RGCs retrograde-labeled from the suprachiasmatic nuclei were no longer intrinsically photosensitive, although their number, morphology, and projections were unchanged. These animals showed a pupillary light reflex indistinguishable from that of the wild type at low irradiances, but at high irradiances the reflex was incomplete, a pattern that suggests that the melanopsin-associated system and the classical rod/cone system are complementary in function. 相似文献
26.
The primary circadian pacemaker, in the suprachiasmatic nucleus (SCN) of the mammalian brain, is photoentrained by light signals from the eyes through the retinohypothalamic tract. Retinal rod and cone cells are not required for photoentrainment. Recent evidence suggests that the entraining photoreceptors are retinal ganglion cells (RGCs) that project to the SCN. The visual pigment for this photoreceptor may be melanopsin, an opsin-like protein whose coding messenger RNA is found in a subset of mammalian RGCs. By cloning rat melanopsin and generating specific antibodies, we show that melanopsin is present in cell bodies, dendrites, and proximal axonal segments of a subset of rat RGCs. In mice heterozygous for tau-lacZ targeted to the melanopsin gene locus, beta-galactosidase-positive RGC axons projected to the SCN and other brain nuclei involved in circadian photoentrainment or the pupillary light reflex. Rat RGCs that exhibited intrinsic photosensitivity invariably expressed melanopsin. Hence, melanopsin is most likely the visual pigment of phototransducing RGCs that set the circadian clock and initiate other non-image-forming visual functions. 相似文献
27.
Signaling by heterotrimeric GTP-binding proteins (G proteins) drives numerous cellular processes. The number of G protein molecules activated by a single membrane receptor is a determinant of signal amplification, although in most cases this parameter remains unknown. In retinal rod photoreceptors, a long-lived photoisomerized rhodopsin molecule activates many G protein molecules (transducins), yielding substantial amplification and a large elementary (single-photon) response, before rhodopsin activity is terminated. Here we report that the elementary response in olfactory transduction is extremely small. A ligand-bound odorant receptor has a low probability of activating even one G protein molecule because the odorant dwell-time is very brief. Thus, signal amplification in olfactory transduction appears fundamentally different from that of phototransduction. 相似文献
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Summary Nineteen durum wheat landraces, cultivars or advanced lines of different origins in West Asia and North Africa (WANA), and three barley and two bread wheat varieties were evaluated for their boron (B) toxicity tolerance. Seedlings were grown at five levels of soluble soil B in a plastic house under controlled temperatures. Significant differences existed between the durum wheat entries in days-to-symptom appearance and foliar symptom score. Under the highest soil B treatment, large differences existed between entries for dry weight per plant (P<0.05) but differences were non-significant for shoot B concentrations. Days-to-symptom appearance was highly correlated with symptom score, which was not correlated with shoot B concentrations. Boron toxicity symptom scores of the durum wheat entries ranged from the sensitive barley check to the moderately sensitive bread wheat check. As expected, days-to-symptom appearance decreased and symptom severity increased as the soil B concentrations increased.The result of this study supported the preliminary finding that small, though statistically significant, variation in B toxicity symptom scores exist in durum wheat. The higher CV of symptom scores found here was mainly due to one sensitive entry, Cakmak. If Cakmak was excluded from the analysis, the CV would be reduced by half, to 10%. Durum wheat genotypes which are more tolerant to B toxicity should be sought. Based on the results of this study, and of soil surveys and information collected in WANA, germplasm collected from Algeria, Iraq, Libya, Syria, and the Anatolian Plateau of Turkey should be screened first.Abbreviations B
boron
- WANA
West Asia and North Africa 相似文献
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