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81.
82.
The commercially available immunoassay "OnSite Rotavirus" was used for the detection of animal rotaviruses in 113 faecal samples. The sensitivity of the test was 88% and the specificity 96% compared with reference methods (EIA, EM). This test would detect approximately 4.4 x 10(6) to 1.8 x 10(7) virus particles per ml. The presence of virus could be demonstrated in fresh faecal samples from cattle, horses and pigs within a few minutes. The rotaviruses of group A were identified independently of the virus serotype. Further results and additional problems of using this test kit are described.  相似文献   
83.
84.
Unconditional quantum teleportation   总被引:5,自引:0,他引:5  
Quantum teleportation of optical coherent states was demonstrated experimentally using squeezed-state entanglement. The quantum nature of the achieved teleportation was verified by the experimentally determined fidelity Fexp = 0.58 +/- 0.02, which describes the match between input and output states. A fidelity greater than 0.5 is not possible for coherent states without the use of entanglement. This is the first realization of unconditional quantum teleportation where every state entering the device is actually teleported.  相似文献   
85.
Inorganic nitrogen (N) determination in soil extracts is a useful tool in studying soil–N interactions. The main method used worldwide is the steam distillation, but colorimetric methodologies show advantages of being quick, simple, sensitive, and higher yield. However, they are subject to disruption when the extract has interfering organic N, limiting its application in tropical soil. The aim of this study is to evaluate colorimetric methods for the determination of NH4+ (through Berthelot reaction) and NO3? + NO2? (through Griess-Ilosvay reaction) in saline extracts of tropical soils by addition of activated charcoal during the extraction process. It is recommended to use extraction solution of 2 mol L?1 potassium chloride (KCl) and reaction time of 30 min. Validation parameters confirmed the best performance of the colorimetric methods, revealing results favorable to the addition of the activated charcoal in the extraction process to increase the accuracy and precision of the colorimetric methods.  相似文献   
86.
Real-time ultrasound imaging was used in a clinical study to estimate the number of follicles of different sizes, ovulation and conception rates, and to study follicle dynamics following oestrus-induction of bitches.
Follicles were identified during late anoestrus (between 100 and 60 days prior to the pre-ovulatory LH surge) and there appeared to be a shift in the population from small follicles (1–3 mm in diameter) to large follicles (>4 mm diameter) approximately 2 days prior to the LH surge. Corpora lutea could be reliably identified although the majority were cavitated. High ovulation rates (97–100%) and pregnant rates (86–100%) were detected, and although the conception rate was approximately 70% it varied between 8 and 92%. Within the narrow range of the clinical population studied there were trends relating age to reproduction performance. Oestrus induction with a gonadotrophin regime appeared to result in large numbers of small follicles that did not ovulate, whilst when using cabergoline the number of small and large follicels and the number of copora lutea were similar to those of control cycles.  相似文献   
87.
This case series of five dogs describes the effects of ingesting large amounts of an iron EDTA snail-bait product. In all cases signs of toxicity occurred between 6 and 24 h after ingestion and included abdominal pain and haemorrhagic gastroenteritis. Two of the dogs had pretreatment serum iron levels measured and in both cases the levels were above normal limits. All of the dogs were treated with iron chelation therapy and supportive care including intravenous fluids, analgesics, gastric protectants and antibiotics. Chelation therapy with desferrioxamine mesylate did not cause adverse effects in any of the dogs and all survived to discharge. The effects of iron EDTA snail bait in dogs requires further study and minimum toxic doses need to be established.  相似文献   
88.
The objectives of the present study were to quantify the effects of a biological chronic stressor (lameness) on the duration and frequency of different oestrous behaviours in parallel with milk hormone profiles. Dairy cows 51.8 ± 1.4 days postpartum (n = 59), including 18 non‐lame control cows, were scored for lameness and closely observed for signs of oestrus having had their follicular phases synchronized by administration of gonadotrophin‐releasing‐hormone (GnRH) followed by prostaglandin F (PG) 7 days later. Lameness shortened the period when herd‐mates attempted to mount the lame cows (1.83 ± 0.69 h vs 5.20 ± 1.53 h; p = 0.042) but did not affect the overall duration of total behaviours (lame 12.3 ± 1.3 h vs non‐lame 15.2 ± 1.3 h). Lameness also lowered the intensity of oestrus [1417 ± 206 points (n = 18) vs 2260 ± 307 points (n = 15); p = 0.029]. Throughout the synchronized oestrous period, lame cows mounted the rear of herd‐mates less frequently (p = 0.020) and tended to chin rest less (p = 0.075). Around the period of maximum oestrous intensity, lameness also diminished the proportion of cows mounting the rear of another cow and chin resting (p = 0.048, p = 0.037, respectively). Furthermore, lame cows had lower progesterone values during the 6 days before oestrous (p ≤ 0.05). Fewer lame cows were observed in oestrus following PG (non‐lame 83%, lame 53%; p = 0.030); however, if prior progesterone concentrations were elevated, lame cows were just as likely to be observed in oestrus. In conclusion, following endogenous progesterone exposure, lameness shortens the period when herd‐mates attempt to mount lame cows but does not affect the incidence of oestrous. However, lame cows are mounted less frequently and express oestrus of lower intensity. This is associated with lower progesterone prior to oestrus but not with abnormal oestradiol or cortisol profiles in daily milk samples.  相似文献   
89.
Even though the respiratory system is one of the most accessible organs for diagnostic testing, it is not always easy to define chronic lower airway disease in the horse. Diagnostic procedures performed by first opinion veterinarians in the field are often restricted to taking the history and performing clinical examination. Respiratory tract endoscopy, tracheal or bronchoalveolar lavage, and blood sampling are sometimes used but other specific ancillary examinations are seldom performed in stable settings. Therefore, our objectives were to evaluate the diagnostic value of different techniques and examination types routinely used in the diagnostic workup of chronic equine lower airway cases in both stable and clinical circumstances. Another aim of this study was to estimate the prevalence of different chronic pulmonary disorders among horses admitted to a Hungarian referral clinic. According to the conditional inference tree method, age of the horse, history, clinical examination, respiratory tract endoscopy, and bronchoalveolar lavage cytology proved to be the most valuable tools to define pathology. It was also concluded that in 22% of cases, more specific ancillary diagnostic modalities, unavailable for the field veterinarian, were needed to establish the final diagnosis. According to our study, the most frequently diagnosed chronic pulmonary disorders in Hungary are of noninfectious origin, principally recurrent airway obstruction. Regardless of the cause, and interestingly including recurrent airway obstruction as well, these diseases occur primarily during the warm months.  相似文献   
90.
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