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Solanum juzepczukii Buk. andSolanum curtilobum Juz. et Buk. are two important primitive cultivated species of potato which are planted in the highlands of Peru and Bolivia. Little natural variation exists within these species. Crosses were made to artificially recreate these species using tetraploid cultivated potatoes as female parents and triploids derived from acaule-diploid crosses as males. The new hybrids were tetraploid (2n = 48) with a high degree of heterosis and variability, and several potential cultivated clones possessing valuable characters such as yield, earliness, frost tolerance and good tuber type were selected.  相似文献   
33.
Four formulations of Chilean hazelnut butter were prepared containing Chilean hazelnut paste and 5%, 10%, 15% and 20% margarine. As the level of margarine was increased to 20%, the protein and crude fiber content decreased markedly, while those of moisture, crude fat and calories increased. After 90 days of storage, neither the samples stored at 5°C nor those stored at 15°C showed any objectionable effects both from the bacteriological and chemical point of view. Sensory analyses, including quality and acceptability studies, were performed on the various blends. Flavor, color and taste were improved by the addition of margarine to the butter formulas. It is concluded, therefore, that Chilean hazelnut butter represents a new and interesting alternative for human nourishment.  相似文献   
34.
Recent studies suggest that ovarian follicular atresia is associated with DNA fragmentation and degeneration of granulosa cells, the hallmark of programmed cell death or apoptosis. Apoptosis of granulosa cells play a major role in follicular atresia. These studies have also demonstrated the involvement of tumour suppressors, apoptotic proteins and survival factors. These factors contribute to the developmental decision as to whether the ovarian follicles mature or undergo atresia. However, the precise temporal and molecular events involved in the apoptotic pathways in this process need to be elucidated. The present report summarizes the role of Jun N‐terminal kinase (JNK), p38 mitogen activated protein kinase (p38 MAPK), and extracellular‐signal regulated kinase (ERK)‐signalling module in the regulation of pro‐ and anti‐apoptotic factors of the granulosa cells in regulating follicular atresia. The findings presented here suggest that the loss of tropic hormone support is translated into the attenuation of Raf‐1‐MAPK/ERK kinase (MEK)‐ERK‐signalling pathway of the granulosa cells and this results in the decreased phosphorylation of the pro‐apoptotic BAD.  相似文献   
35.
2,5-dihydroxy-3,4-dimethoxyphenanthrene (1), fimbriol-A (2), nudol (3), gymnopusin (4) and erianthridin (5) isolated from Maxillaria densa provoked a concentration-dependent inhibition of the spontaneous contractions of the rat ileum with potencies comparable to papaverine. In order to establish the mode of action of stilbenoids 1-5, their effect on the contractions induced by different spasmogens (histamine, barium chloride and L-NAME) was investigated. In general, the results suggested that the relaxant activity of the products does not involve a direct nitrergic or antihistaminergic mode of action or an interference with calcium influx into the smooth muscle cells.  相似文献   
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Using data from bluetongue (BT) outbreaks caused by viral serotype 4 (BTV-4) in Spain during 2004–2005, a predictive model for BTV-4 occurrence in peninsular Spain was developed. An autologistic regression model was employed to estimate the relationships between BTV-4 presence and bioclimatic-related and host-availability-related variables. In addition, the observed abundances of the main potential Culicoides vectors during 2004–2005, namely Culicoides imicola, Culicoides obsoletus group, and species of the Culicoides pulicaris group, were compared between BTV-4 presence/absence areas predicted by the model.BTV-4 occurrence was mainly explained by bioclimatic variables, although a consideration of host-availability variables led to improved fit of the model. The area of BTV-4 presence predicted by the model largely resembled the core distribution area of C. imicola, and this species was the most abundant Culicoides spp. in predicted BTV-4 presence areas. The results suggest that the spatial expansion of BTV-4 took place only as far as those areas in which C. imicola populations efficiently transmitted the virus.  相似文献   
38.
ObjectiveTo investigate a combination of azaperone, detomidine, butorphanol and ketamine (DBK) in pigs and to compare it with the combination of azaperone, tiletamine and zolazepam (TZ).Study designProspective, randomized, blinded, cross–over study.AnimalsTwelve clinically healthy crossbred pigs aged about 2 months and weighing 16–25 kg.MethodsPigs were pre–medicated with azaperone (4 mg kg?1). Ten minutes later anaesthesia was induced with intramuscular DBK (detomidine 0.08 mg kg?1, butorphanol 0.2 mg kg?1, ketamine 10 mg kg?1) or TZ (tiletamine and zolazepam 5 mg kg?1). The pigs were positioned in dorsal recumbency. Heart and respiratory rates, posture, anaesthesia score, PaO2, PaCO2, pH and bicarbonate concentration were measured. t–test was used to compare the areas under time–anaesthesia index curve (AUCanindex) between treatments. Data concerning heart and respiratory rates, PaO2, PaCO2 and anaesthesia score were analysed with anova for repeated measurements. Wilcoxon signed rank test was used for the data concerning the duration of sedation and anaesthesia.ResultsThe sedation, analgesia and anaesthesia lasted longer after DBK than TZ. The AUCanscore were 863 ± 423 and 452 ± 274 for DBK and TZ, respectively (p = 0.002). The duration of surgical anaesthesia lasted a median of 35 minutes (0–105 minutes) after DBK and a median of 15 minutes (0–35 minutes) after TZ (p = 0.05). Four pigs after DBK and six after TZ did not achieve the plane of surgical anaesthesia. The heart rate was lower after DBK than after TZ. Both treatments had similar effects on the other parameters measured.ConclusionsAt the doses used DBK was more effective than TZ for anaesthesia in pigs under field conditions.Clinical relevanceThe combinations can be used for sedation and minor field surgery in pigs. The doses and drugs chosen were insufficient to produce a reliable surgical plane of anaesthesia in these young pigs.  相似文献   
39.
A dog that was referred to the University of Florida Veterinary Medical Center was discovered to have a bamboo skewer within the right atrium and right ventricle, traversing the tricuspid valve. The skewer was ingested approximately four months prior to referral and was partially removed via gastrotomy. The presenting complaint at the time of referral included coagulopathy, anemia and leukocytosis. A linear, hyperechoic structure was identified in the right heart during an echocardiogram. The foreign body was suspected to be a portion of the skewer that the patient had previously ingested. Cardiopulmonary bypass was performed and the foreign body was removed successfully. Complications following surgery included the development of tricuspid valve and ventricular wall thrombi, atrial flutter and amiodarone toxicity. Many indications have been described in the veterinary literature for cardiopulmonary bypass. However, to the best of the authors' knowledge, successful removal of an intracardiac foreign body with cardiopulmonary bypass has not been reported in a veterinary patient. This represents a new indication for cardiopulmonary bypass in veterinary medicine.  相似文献   
40.
OBJECTIVES: To determine the prevalence of gastrointestinal tract lesions in brachycephalic dogs with upper respiratory tract disease. METHODS: The gastrointestinal tract and respiratory disorders of 73 brachycephalic dogs presented with upper respiratory signs were evaluated. Clinical signs and endoscopic and histological anomalies of the upper digestive tract were analysed. RESULTS: A very high prevalence of gastrointestinal tract problems in brachycephalic dogs presented with upper respiratory problems was observed clinically, endoscopically and histologically. Endoscopic anomalies of the upper digestive tract were present even in dogs without digestive clinical signs. Furthermore, histological evaluation of the digestive tract sometimes showed inflammatory lesions not macroscopically visible at endoscopy. Statistical analysis showed a relationship between the severity of the respiratory and digestive signs. This was significant in French bulldogs, males and heavy brachycephalic dogs. CLINICAL SIGNIFICANCE: These observations show a correlation between upper respiratory and gastrointestinal tract problems in brachycephalic breeds with upper respiratory disease. Surgical treatment of respiratory disease could improve the digestive clinical signs, and/or gastro-oesophageal medical treatment could improve the outcome for surgically treated brachycephalic dogs.  相似文献   
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