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31.
Gold T 《Science (New York, N.Y.)》1969,165(3900):1345-1349
Some glazing is apparently due to radiation heating; it suggests a giant solar outburst in geologically recent times.  相似文献   
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BackgroundThe repeated administration of high doses of gabapentin may provide better analgesia in horses than current clinical protocols.Hypothesis and ObjectivesAdministration of gabapentin at 40 and 120 mg/kg PO q 12 h for 14 days will not alter serum biochemistry findings or cause adverse effects. Our objectives were to evaluate the effect of gabapentin on serum biochemistry, physical examination, and plasma pharmacokinetics of gabapentin.AnimalsSix healthy adult mares.MethodsHorses received 40 and 120 mg/kg of gabapentin orally q 12 h for 14 days. Horses were examined and scored for ataxia and sedation daily. Serum biochemistry variables were analyzed before treatment and days 7 and 14 after gabapentin administration. Plasma disposition of gabapentin was evaluated after the first and last drug administration. Pharmacokinetic parameters were estimated using noncompartmental analysis.ResultsNo changes occurred in physiologic or biochemical variables. Median (range) maximal plasma gabapentin concentrations (μg/mL) after the last dose (day 15) were 7.6 (6.2‐11) and 22 (14‐33) for 40 mg/kg and 120 mg/kg doses respectively. Maximal concentration of gabapentin was reached within 1 hour after drug administration. Repeated administration of gabapentin resulted in a median (range) area under the curve (AUC0‐12 hours) last/first dose ratio of 1.5 (1.00‐2.63) and 2.92 (1.4‐3.8) for the 40 and 120 mg/kg regimens, respectively.Conclusion and Clinical ImportanceOur results suggest that horses tolerate gabapentin up to 120 mg/kg PO q 12 h for 14 days. The analgesic effect of the dosage regimens evaluated in our study warrants further research.  相似文献   
34.
Commercially farmed, hybrid striped bass - female white bass (Morone chrysops) crossed with male striped bass (Morone saxatilis) - represent a rapidly growing industry in the United States. Expanded production of hybrid striped bass, however, is limited because of uncontrolled variation in performance of fish derived from undomesticated broodstock. A 10 × 10 factorial mating design was employed to examine genetic effects and heritability of growth-related traits based on dam half-sib and sire half-sib families. A total of 881 offspring were raised in a common environment and body weight and length were recorded at three different times post-fertilization; parentage of each fish was inferred from genotypes at 10 nuclear-encoded microsatellites. Dam and sire effects on juvenile growth (weight and length) and growth rate were significant, whereas dam by sire interaction effect was not. The dam and sire components of variance for weight and length (at age) and growth rate were estimated using a Restricted Maximum Likelihood algorithm. Estimates of broad-sense heritability of weight, using a family-mean basis, ranged from 0.67 ± 0.17 to 0.85 ± 0.07 for dams; estimates for sires ranged from 0.43 ± 0.20 to 0.77 ± 0.10. Estimates of broad-sense heritability of growth rate (based on weight), using a family-mean basis, ranged from 0.69 ± 0.12 to 0.82 ± 0.09 for dams and from 0.69 ± 0.13 to 0.81 ± 0.08 for sires. Similar results were obtained with length data. Both genetic and phenotypic correlations between weight and length were close to unity. High genetic (0.98-0.99) and phenotypic (0.79) correlations between growth rates measured at two time intervals suggested that selection for growth rate at an early life stage could affect growth rate at a later life stage. Estimates of general combining ability (GCA) for growth rates differed significantly among dams and among sires, whereas estimates of specific combining ability (SCA) for each dam × sire combination did not differ significantly from zero. These results suggest that additive-effect genes contributed to the differences in juvenile growth.  相似文献   
35.
Gold T 《Science (New York, N.Y.)》1967,157(3786):302-304
Radio interferometry with independent high-precision clocks, without a high-frequency communication channel between the stations, is now a possibility. It allows the stations to be as far apart as the earth can accommodate. This then makes the radio band from 10- to 60-centimeters wavelength the best frequency range for high-precision angular measurements, since the variability of the atmosphere is less disturbing there than in the optical band.  相似文献   
36.
West Nile virus (WNV) is a zoonotic pathogen of global importance. In horses with neurological signs, detection of WNV-specific immunoglobulin M (IgM) in serum is widely used to identify clinical cases of WNV encephalitis. Here, we describe the development of two monoclonal antibodies (mAbs) to equine IgM which were used in a WNV IgM-specific enzyme-linked immunosorbent assay (ELISA). Their performance was compared to an established assay based on polyclonal anti-IgM. Check test serum samples from the National Veterinary Service Laboratory (NVSL) were used to evaluate the performance of the three anti-IgM antibodies. The anti-IgM 1-22 mAb correctly identified all NVSL samples. Both the polyclonal antibody and monoclonal anti-IgM 2B-63 identified eight out of ten samples correctly. The three assays were then compared using serum samples from clinically healthy animals (n=33) and horses with neurological signs (n=21). High Spearman rank correlations (0.76-0.86) were found among the ELISA results. Inter-test agreements (weighted kappa) for assay interpretation resulted in strong agreement (0.95) of the results obtained by the mAbs and moderate agreements when monoclonal and polyclonal anti-IgM-based assays were compared. To determine the analytical sensitivities of anti-WNV IgM detection, serial dilutions of WNV IgM-positive serum samples were analyzed. The highest sensitivity was obtained by using the anti-IgM 1-22 mAb to capture IgM from equine serum. In conclusion, the use of monoclonal anti-IgM antibodies can improve the sensitivity of IgM detection in the acute phase of WN disease.  相似文献   
37.
Sagittal groove injuries of the proximal phalanx are an important cause of lameness in performance horses. The purpose of this retrospective case series study was to describe standing low‐field magnetic resonance imaging (MRI) characteristics of these injuries in a group of Warmblood horses. Horses with an MRI diagnosis of sagittal groove injuries involving the proximal phalanx and that had follow‐up MRI and clinical outcome information were included. Findings from clinical examinations, diagnostic tests, and other imaging modalities were recorded. All MRI studies were retrieved for re‐evaluation by an experienced, board‐certified veterinary radiologist. A total of 19 horses met inclusion criteria. All horses had MRI lesions consistent with unilateral or bilateral sagittal groove injuries of the proximal phalanx and abnormal mineralization of the sagittal ridge of the third metacarpal/metatarsal bone. Fifteen horses (79%) had concurrent osteoarthritis of the affected metacarpophalangeal/metatarsophalangeal joint. Eighteen horses received conservative therapy and all horses still had osseous abnormalities detected at the time of follow‐up MRI. Thirteen horses (68.5%) were still lame at the time of follow ‐ up, whereas the other six horses (31.5%) had become sound and returned to the previous level of exercise. Findings indicated that, for mature Warmblood horses, acute or chronic injuries of the sagittal groove of the proximal phalanx may have variable standing low‐field MRI characteristics. Based on this sample of 19 horses, findings also indicated that the prognosis for performance soundness in horses diagnosed with sagittal groove injury of the proximal phalanx and concurrent osteoarthritis is poor.  相似文献   
38.
Reference ranges for triglycerides, insulin, cortisol, and adrenocorticotropic hormone (ACTH) are used in diagnosing hyperlipemia and pituitary pars intermedia dysfunction (PPID) in the donkey. Values are currently compared to reference ranges of the horse so as to diagnose disease. Previous studies found differences between hematological, serum biochemical, and hormone values of the horse and donkey. We suspected that similar differences existed between horse and donkey triglyceride, insulin, cortisol, and ACTH levels. Blood samples were drawn from 44 healthy mammoth donkeys and 1 miniature donkey, ranging in age from 3 weeks to 21 years, and varying in sex and pregnancy status. All but one donkey scored 3 of 5, “ideal,” body condition scoring. Samples were tested for triglycerides, insulin, cortisol, and ACTH levels. A marked difference was found between horse and donkey normal values for triglycerides, insulin, and ACTH. The mean values and standard deviation in the tested population were 66.4 ± 34.2 mg/dL for triglycerides, 2.1 ± 2.05 μU/mL for insulin, and 66.7 ± 20.7 pg/mL for ACTH. The reference ranges in the horse are 14–77 mg/dL for triglycerides, 4.9–45.5 μU/mL for insulin, and 18.7 ± 6.8 pg/mL for ACTH. Cortisol levels were similar in the two species, a 4.0 ± 1.2 μg/dL for donkeys being within the reference range for the horse, 2.9–6.6 μg/dL. Values were not correlated to age. The sample size prevented us from determining any correlation according to sex or pregnancy status. Differences between horse and donkey triglyceride and ACTH values may be significant for accurately diagnosing and treating hyperlipemia and PPID, respectively, in the donkey.  相似文献   
39.
Both E. coli and S. aureus were simultaneously injected into the left renal arteries of 55 female dogs. The arteries were occluded for 10 minutes prior to the injection and 10 minutes after. The renal veins were occluded during the injection and for 10 minutes after.

Ten animals did not survive longer than 24 hours. Ten of 45 developed neither renal lesions nor bacteriuria; of the remaining 35 which did, five were killed on each of the second, seventh and fourteenth days, and their renal lesions were assessed. Eighteen of the remaining 2 which developed bacteriuria were killed 3 to 12 weeks following surgery when bacteria could no longer be recovered from the urine. Only two dogs had persistent bacteriuria 12 weeks after surgery. All animals which developed bacteriuria had gross lesions in the left kidney but not the right.

Naturally occurring renal lesions were found in 17 of 78 random-source dogs at laparotomy. E. coli was cultured from the urine of five of these dogs but not from the kidneys. These lesions were morphologically similar to experimental ones.

It is concluded that with this method renal lesions similar to spontaneous ones can be produced, but care must be taken to exclude the relatively large percentage of random-source dogs with naturally occurring lesions from any study.

Various forms of infectious nephritis have been reported to be among the commonest diseases of dogs (1, 2). The successful production of chronic pyelonephritis in dogs depends on a variety of factors in addition to injecting bacteria into either the renal artery or ureter. Thus, ureteral obstruction, renal anoxia and reduced pulse pressure increased the susceptibility to renal infection (3, 4, 6, 7, 8).

Our laboratory has been concerned with the production of experimental pyelonephritis in dogs so that the efficacy of various treatments could be studied. The present work was undertaken to standardize methods of producing the disease and to compare experimental renal lesions with naturally occurring ones.

  相似文献   
40.
Gold T  Soter S 《Science (New York, N.Y.)》1970,169(3950):1071-1075
The seismic signal caused by the Apollo 12 lunar module is interpreted in terms of propagation between source and receiver through a layer of powder in which sound velocity increases with depth. This increase, which is due to compaction, extends over several kilometers and leads to a concentration of seismic waves toward the surface. Computer simulations with the use of ray acoustics and on the assumption of a randomly undulating lunar surface approximate well the observed signal. Seismic amplitudes are greatly enhanced in such a medium compared to solid rock, so that the observed signal requires less power to be transmitted than previously estimated.  相似文献   
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