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31.
印度每年可产1500万吨的香蕉,占全球香蕉产量的19%。但因国内消费量过大,导致其出口量所占全球香蕉出口份额不到1%。香蕉生产公司(Bancom)主席称,印度是最大的香蕉生产国和消费国,但还必须增加出口量,而海湾国家将成为印度香蕉出口的主要目标国。由于印度邻近中东市场,运输成本  相似文献   
32.
Dihydroferulic acid (DFA) and dihydrosinapic acid (DSA) were isolated from Kurosu (unpolished rice vinegar) as the major constituents responsible for Kurosu's radical scavenging activity. The levels of antioxidative activity of DFA and DSA in DPPH radical scavenging were higher than those of their respective structurally related compounds, ferulic acid and sinapic acid. The concentrations of DFA and DSA were low in common rice vinegar (polished rice vinegar), suggesting that Kurosu is more advantageous than rice vinegars as an antioxidative food item. As the concentrations of DFA and DSA were low in unpolished rice, too, these acids are thought to be produced in Kurosu through the process of the fermentation from ferulic acid and sinapic acid, respectively.  相似文献   
33.
Estrogen and its receptors are essential for sexual development and reproduction. Oestrogen receptor alpha (ERα) is a nuclear receptor activated by the hormone oestrogen. In male, ERα is encoded by the gene ESR1 (oestrogen receptor1) responsible for better fertility. ESR1 is involved in the reabsorption of luminal fluid during the transit of spermatozoa from the testis to the head of the epididymis which is important for their survival and maturation during epididymal storage. The absence of ESR1 leads to reduced epididymal sperm content, reduced sperm motility and fertilizing ability. The present study was undertaken to investigate the expression and presence of ESR1 gene in fertile and low-fertile male goat breeds. We identified ESR1 gene through various molecular tools. Genotyping was carried out by high resonance melting analysis using Roche Light Cycler 480(LC-480) system and found three different genotypes. Genotypic frequency-AA (blue-0.67), BB(Red-0.2), AB(Green-0.08) with allele frequency A(0.71 and B (0.29). The predominance of this gene in head of epididymis in fertile bucks was confirmed by SDS-PAGE, Western blotting and immunohistochemistry. From the results, we corroborated that the present study provides a useful and effective way to predict male fertility in goat breeds, which in turn increases the percentage of fertility in flock leading to more number of offspring in a kidding season.  相似文献   
34.
The luteinising hormone (LH) surge in response to 1 mg oestradiol benzoate intramuscular injection was studied on 67 occasions in 45 cows with cystic ovarian disease 20 to 150 days post partum. Cows diagnosed as having luteal cysts were given 500 micrograms cloprostenol intramuscularly 24 hours before oestradiol, to induce luteolysis. Oestradiol benzoate was also given to eight post partum acyclic and eight cyclic cows and in all these cases a control LH response was characterised for comparison. Eight of 17 cows with luteal cysts (47 per cent), and 10 of 21 cows with follicular cysts (48 per cent), released LH in response to oestradiol. Some cows with cysts were given one of two treatments. Seven cows with follicular cysts were treated with a progesterone-releasing device (PRID) for seven days: all responded to a second oestradiol treatment given 24 hours after removal of the PRID. Luteal cysts in three cows and follicular cysts in nine cows were ruptured manually: only one cow (a luteal case) responded to the second oestradiol treatment given 24 hours after manual rupture. In eight cows initially diagnosed with luteal cysts, cloprostenol was not given and plasma progesterone concentration at the time of oestradiol treatment was high (over 0.9 ng ml-1): none released LH in response to oestradiol. As manual rupture did not improve the LH response to oestradiol, it is concluded that the defective LH response to oestradiol in cows with cystic ovarian disease was not influenced in the short-term by cyst fluid contents.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
35.
Objective To determine the clinical skills and areas of knowledge used by veterinarians in small animal practice during their first year after graduation and the degree of assistance and supervision they received while developing these skills. Design A postal survey was sent in December 1999 to 59 veterinarians who completed their training at Murdoch University in December 1998. Procedure The first part of the survey asked for information on veterinary work patterns since leaving university. The second part consisted of a list of diagnostic and therapeutic skills of varying complexity and the graduates were asked to indicate whether they had used these skills in practice and whether they had been assisted or supervised while doing them. The respondents were also asked if they had had the opportunity to practise these skills as undergraduates at university or during extramural experience. In the third part the areas of knowledge used in practice were assessed by analysis of a series of consecutive cases. Results Forty replies were received but since three graduates had done no small animal work the analysis of the skills section is based on 37 responses. Thirty graduates supplied information on 994 canine cases and 308 feline cases. The distribution of the mean work time was dogs and cats 69%, horses 13%, farm animals 11%, birds 3% and others 4%. Skills used by over 90% of graduates included general anaesthesia, examination of the tympanic membrane, taking and interpreting an abdominal radiograph, catheterising a male cat, fine needle aspiration of a mass, neutering dogs and cats, tooth scaling and extraction and treating an aural haematoma. The survey also identified the opportunities for undergraduates to practise some of these skills during extramural experience and the extent of assistance given to new graduates during their first year in practice. The areas of knowledge used in over 10% of the cases included vaccination, anaesthesia/sedation, skin/coat problems, general advice on pet health, neutering and musculoskeletal diseases. Conclusion Veterinarians, in their first year after graduation, use a wide range of complex diagnostic and therapeutic skills. Although many of these skills are acquired during the undergraduate training, a significant contribution is made by extramural practical work undertaken during the clinical years of the undergraduate course and in the first year following graduation. Practising veterinarians play an important role in providing opportunities and supervision for clinical training.  相似文献   
36.
Objective To provide serological data to support Australia's claim of freedom from porcine reproductive and respiratory syndrome.
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus.  相似文献   
37.
38.
Some intriguing bedding plane features that were observed in the Mesoproterozoic Chorhat Sandstone are biological and can be interpreted as the burrows of wormlike undermat miners (that is, infaunal animals that excavated tunnels underneath microbial mats). These burrows suggest that triploblastic animals existed more than a billion years ago. They also suggest that the diversification of animal designs proceeded very slowly before the appearance of organisms with hard skeletons, which was probably the key event in the Cambrian evolutionary explosion, and before the ecological changes that accompanied that event.  相似文献   
39.
40.
This study investigated whether the stress associated with a 30-minute journey in a truck could distort the oestradiol-induced surge of luteinising hormone (LH) in dairy cows. Altogether 20 journeys were monitored, 16 to 18 hours after intramuscular administration of 1 mg oestradiol benzoate (OE2). Plasma cortisol concentration was elevated (P less than 0.001) within 30 minutes of the start of each journey, even when the journey was repeated at about weekly intervals, indicating a lack of habituation. The LH surge in response to 11 OE2 treatments in nine non-cycling cows within 30 days after calving was either absent (one cow) or significantly delayed, of shorter duration or of lesser amplitude following transport, compared with untransported OE2-treated controls. However, in six cycling cows, 58 days or more after calving, transport affected the LH surge only once. Even in these cows, the LH surge did not start until the cortisol concentration returned to normal, which may suggest a transient postponement of the LH surge by transport. In conclusion, transport impaired the LH surge in early post partum cows with little or no effect after ovarian cyclicity was resumed. It is hypothesised that endocrine events leading to the onset of the LH surge are more vulnerable to stressors in early post partum cows and in the natural situation this might be responsible for the occurrence of anovulation and cystic ovarian disease.  相似文献   
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