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961.
Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single (17)O-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is (16)O-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion.  相似文献   
962.
This work was done to determine the salicylate content of a variety of commonly used spices and to assess whether this potential dietary source of salicylate was bioavailable. Spices, Indian cooked dishes, and blood and urine samples taken after ingestion of a test meal were investigated for their salicylate content using high-performance liquid chromatography with electrochemical detection. The serum salicylic acid concentrations in samples from villagers in southern India were also measured and have been compared with typical European values. Salicylic acid was determined in all spices (up to 1.5 wt %) and cooked dishes. The salicylate content of blood and urine was shown to increase following consumption of the meal, indicating that this dietary source of salicylic acid was bioavailable. Salicylic acid levels in the serum from rural Indians were significantly (median almost 3-fold) higher than values previously measured in Western vegetarians. Chemoprotective aspirin is rapidly hydrolyzed to salicylic acid, and this phytochemical may contribute to the low cancer incidence in rural India.  相似文献   
963.
964.
OBJECTIVE: To determine whether bupivacaine peripheral nerve block of the saphenous, tibial and common peroneal nerves proximal to the femoro-tibial joint reduces peri-operative pain following extracapsular surgical stabilization of cranial cruciate ligament rupture in the nonchondrodystrophoid dog. ANIMALS: Forty-one dogs with naturally acquired femoro-tibial joint instability. Study design Randomized, controlled, clinical trial. METHODS: Dogs diagnosed with suspected cranial cruciate ligament injury based on physical and radiographic evidence were randomly assigned to treatment (bupivacaine) or control (saline) nerve blocks before femoro-tibial joint surgery. Pain scores, skin sensation, pain threshold to incisional pressure, time to first systemic 'rescue' opioid analgesic and total analgesic dose were evaluated for 24 hours. p < 0.05 was considered significant. RESULTS: Treatment dogs had a significantly longer period of cutaneous desensitization than control dogs. There were no significant differences between treatment and control groups for pain score, pain threshold to incisional pressure, or time to first-rescue analgesic. The treatment group received significantly more supplemental analgesics than the control group. CONCLUSIONS: These peripheral nerve blocks were easy to perform and resulted in significant desensitization of the associated nerve autonomous zones, but did not improve post-operative analgesia. CLINICAL RELEVANCE: Clinical benefit was not detected when using this technique for peri-operative pain management following extracapsular cranial cruciate ligament surgical stabilization.  相似文献   
965.
Madam:— In the September issue (N.Z. vet. J. (1985) 33:154), D. and A.K. Dodd, and Messrs Jackson, Mulvaney, Bishop and Jopp write in support of the introduction of myxomatosis into New Zealand, seeing it “as the only means of protecting the fragile environment of the South Island High Country from complete destruction by the rabbit.”  相似文献   
966.
967.
968.
Sir, — It may be of interest to some rural practitioners, having an upsurge in requests for opthalmoscopic examinations of working dogs, to know that at present this practice is engaged in examinations at the National dog trials. Retinal disease is an increasing problem in both Huntaways and Heading dogs in this country. This is probably a result of the extensive use of selected strains and the tendency for the breeds to become more uniform with farmers keeping fewer better-bred dogs. Work on this complex condition is however in its infancy, and a great deal is yet to be resolved. At this stage histological sectioning suggests an inflammatory component, but computer pedigree analysis suggests a heretibility of 0.33 — 0.40. In the main the condition is not analogous to central P.R.A. present in the British Border Collie, despite its ancestral contribution particularly to the Heading dog.  相似文献   
969.
A trial on ‘Fuji’ apples at the Grove Research Station in southern Tasmania during the 1991/92 season studied the thinning effect and interactions between ethephon and benzyladenine (BA) when BA was applied as a secondary thinner after a full bloom (FB) application of ethephon. The spray treatments were a factorial combination of eight application times of BA (11,13,15,17,19, 21, 23 or 25 days after full bloom (AFB)) with ten concentrations (20,40,60,80,100,120,140,160,180 or 200 mg I“1). An unsprayed control and an ethephon control were included. Target thinning results were achieved 19- 23 d AFB with concentrations of 140-160 mg I“1. A corollary of this successful thinning was an increase in fruit weight and size. Return bloom was improved significantly where thinning was successful. There was no effect on fruit firmness, soluble solids or lateral branching. Drawbacks were an increase in the incidence of russet and a reduction in pip number at the optimum thinning times and concentrations.  相似文献   
970.
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