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101.
102.
The maturation and developmental potential on cumulus-cell-free oocytes is of great importance theoretically and practically. The present study was to investigate the effects of l -ascorbic acid, α-tocopherol and co-culture on in vitro developmental potential of porcine denuded oocytes (DOs). Porcine DOs were cultured in maturation medium supplemented with vitamin C (0, 50, 100, 250, 500, 750 μM) and vitamin E (0, 10, 20, 50, 100, 250 μ m ), respectively. And they were also co-cultured with dispersed cumulus cells (group CCscoculture), intact cumulus cells oocyte complexes (COCs) (group COCscoculture), and COCs whose oocytes were removed (group OOXcoculture), respectively. After 44 h incubation, the maturation rates, cleavage rates and blastocyst rates after parthenogenetic activation in three experiments mentioned above were collected and analysed, respectively. L -Ascorbic acid promoted porcine DOs in vitro maturation and blastocyt development after parthenogenetic activation while α-tocopherol did not increase the in vitro maturation rates, but improved the blastocyst rate. None of the three co-culture manner promoted the in vitro maturation and the cleavage of porcine DOs after parthenogenetic activation, but all the co-culture manners improved the blastocyst rates. Both Vitamin C and E enhance the in vitro developmental potential of porcine DOs. Co-culture increases the developmental potential of porcine DOs.  相似文献   
103.
Schutz  JP 《Forestry》1999,72(4):359-366
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104.
Congenital myasthenic syndromes (CMSs) are a group of inherited disorders of neuromuscular transmission characterized by fatigable muscle weakness. One major subgroup of patients shows a characteristic "limb girdle" pattern of muscle weakness, in which the muscles have small, simplified neuromuscular junctions but normal acetylcholine receptor and acetylcholinesterase function. We showed that recessive inheritance of mutations in Dok-7, which result in a defective structure of the neuromuscular junction, is a cause of CMS with proximal muscle weakness.  相似文献   
105.
ABSTRACT

Aims: The main goal of the current study was to evaluate, on a commercial beef cattle farm, the impact of infection with gastrointestinal nematodes resistant to both ivermectin (IVM) and moxidectin (MXD) on the productivity of calves.

Methods: Male Aberdeen Angus calves, aged 9–11 months, with faecal nematode egg counts (FEC) ≥200 epg and body weight ≥190?kg, were allocated to two herds. Herd A (n?=?90) grazed a maize-winter forage crop rotation and Herd B (n?=?90) grazed a 2-year-old Agropyrum pasture. On Day 0 in each herd, calves were randomly allocated into five groups (n?=?18), which were treated with 0.2?mg/kg IVM; 0.2?mg/kg MXD; 3.75?mg/kg ricobendazole (RBZ), both IVM and RBZ, or remained untreated. Faecal samples collected on Days ?1 and 19 were used to determine the percentage reduction in FEC, and genera of the nematodes were determined by the identification of the third-stage larvae recovered from faecal cultures. Total weight gain was determined from body weights recorded on Days ?1 and 91.

Results: Overall mean reduction in FEC was 42% for IVM, 67% for MXD, 97% for RBZ and 99% for IVM?+?RBZ. The reduction in FEC for Cooperia spp. was ≤78% for IVM and MXD, and for Haemonchus spp. was 0 and 36% for IVM and MXD, respectively, confirming the presence of parasites resistant to both anthelmintics. Only IVM?+?RBZ treatment resulted in 100% efficacy against Haemonchus spp. The overall estimated mean total weight gain for calves treated with IVM was 15.7 (95% CI?=?11.9–19.7) kg and for calves treated with IVM?+?RBZ was 28.8 (95% CI?=?25–32.5) kg (p?<?0.001). Mean total weight gain for calves treated with MXD was 23.5 (95% CI?=?19.7–27.2) kg.

Conclusions and clinical relevance: In calves naturally infected with resistant nematodes, under the production system assessed here, weight gains were lower in calves treated with anthelmintics that were moderately or highly ineffective compared to those treated with highly effective anthelmintics. These results demonstrate to farmers and veterinarians the importance of a sustainable and effective nematode control under field conditions.  相似文献   
106.
Recent determinations of the Newtonian constant of gravity have produced values that differ by nearly 40 times their individual error estimates (more than 0.5%). In an attempt to help resolve this situation, an experiment that uses the gravity field of a one-half metric ton source mass to perturb the trajectory of a free-falling mass and laser interferometry to track the falling object was performed. This experiment does not suspend the test mass from a support system. It is therefore free of many systematic errors associated with supports. The measured value was G = (6.6873 +/- 0. 0094) x 10(-11) m3 kg-1 sec-2.  相似文献   
107.
A general method is introduced for the rapid and simultaneous evaluation of each member of large encoded catalyst libraries for the ability to catalyze a reaction in solution. The procedure was used to select active catalysts from a library of potential polymer-bound multifunctional catalysts. From approximately 7000 beads screened (3150 distinct catalysts), 23 beads were selected for catalysis of an acylation reaction. Kinetic experiments indicate that the most strongly selected beads are also the most efficient catalysts.  相似文献   
108.
109.
Fawcett D 《The Veterinary record》2011,168(10):281; author reply 281-281; author reply 282
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110.
CASE PRESENTATION AND ASSESSMENT: A 3-month-old female Cornish Rex kitten was found to have non-painful swelling of the carpal and tarsal regions when presented for routine neutering. The kitten was smaller in stature and less active than its siblings and, according to the owner, had a bunny-hopping gait, was reluctant to climb stairs and strained during defecation. Radiography of the affected limbs and a subsequent radiographic survey of the entire skeleton demonstrated features consistent with rickets. The three littermates were clinically and radiographically normal. As a nutritionally complete diet was being fed, it seemed most likely that the kitten had an inborn error related to vitamin D metabolism. Serum biochemistry demonstrated reduced total alkaline phosphatase activity and increased concentrations of parathyroid hormone. Concentrations of 1,25- and 25-hydroxycholecalciferol were markedly reduced, confirming the diagnosis of rickets. TREATMENT: The kitten was treated with calcitriol, administered orally once daily, and improved rapidly both clinically and radiologically. Serial laboratory studies suggested that the error in vitamin D metabolism was transient, and, at the time of writing, as an adult, the cat appears to require no ongoing replacement calcitriol therapy. CLINICAL RELEVANCE: This case emphasises the value of examining a full 'calcium profile' via a human or veterinary reference laboratory, and a favourable prognosis in some kittens with rickets makes such investigations worthwhile. Even when finances preclude detailed investigation, trial therapy using a nutritionally complete diet and physiological doses of calcitriol or cholecalciferol is inexpensive and can produce a good response.  相似文献   
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