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71.
JR Delaney DS Kelley MD Lilley DA Butterfield JA Baross WSD Wilcock RW Embley M Summit 《Science (New York, N.Y.)》1998,281(5374):222-230
Seafloor diking-eruptive events represent the irreducible, quantum events of upper oceanic crustal accretion. They record events by which a large portion of the oceanic crust has formed through geological history. Since 1993, the U.S. Navy's real-time Sound Surveillance System has allowed location of ongoing acoustic signatures of dike emplacement and basalt eruptions at ridge crests in the northeast Pacific. These diking-eruptive events trigger a sequence of related, rapidly evolving physical, chemical, and biological processes. Magmatic volatiles released during these events may provide nutrients for communities of subseafloor microorganisms, some of which thrive in high-temperature anaerobic environments. Many of the organisms identified from these systems are Archaea. If microorganisms can thrive in the water-saturated pores and cracks within deep, volcanically active portions of our planet, other hydrothermally active planets may harbor similar life forms. 相似文献
72.
73.
The structure of the upper atmosphere of mars: In situ accelerometer measurements from mars global surveyor 总被引:1,自引:0,他引:1
GM Keating SW Bougher RW Zurek RH Tolson GJ Cancro SN Noll JS Parker TJ Schellenberg RW Shane BL Wilkerson JR Murphy JL Hollingsworth RM Haberle M Joshi JC Pearl BJ Conrath MD Smith RT Clancy RC Blanchard RG Wilmoth DF Rault TZ Martin DT Lyons PB Esposito MD Johnston al et 《Science (New York, N.Y.)》1998,279(5357):1672-1676
The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90 degreesE and 90 degreesW, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere. 相似文献
74.
Resection and anastomosis of the small colon was performed on 4 horses with vascular lesions (strangulating lipoma, mesenteric tear, dissecting haematoma) or functional obstruction (stricture) of this area of the bowel. The anastomoses were performed using a variety of suture materials in 2 layers. An appositional, full-thickness, simple, interrupted pattern was used in the first layer in all cases and oversewn with either a Cushing pattern (3 cases) or a Utrecht pattern (1 case). Post-operative complications associated with suture material and surgical technique were not seen. All horses were discharged from the hospital and all were alive more than one year after discharge. 相似文献
75.
Robert B. Duncan JR DVM PHD Jeryl C. Jones DVM PHD H. David Moll DVM MS Martha M. Moon DVM MS Dennis J. Blodgett DVM PHD Michael R. Vaughan PHD 《Veterinary radiology & ultrasound》2002,43(1):31-36
Congenital hyperplastic goiter and cretinism were documented in a 16 month-old male North American black bear (Ursus americanus). The cub was captured at approximately 8 months of age and maintained for an additional 8 months in captivity. Clinical signs included growth retardation, clumsiness, and facial dysmorphism. Hypothyroidism was documented by determining serum triiodothyronine (T3) and thyroxine (T4) levels. Lysosomal storage disease was ruled out by measuring various lysosomal enzyme activities. Serologic, radiographic, computed tomographic, necropsy, and histopathologic findings were consistent with congenital hypothyroidism and cretinism. 相似文献
76.
LUISITO S. PABLO DVM MS Diplomate ACVA ALISTAIR I. WEBB BVSC PhD FRCVS Diplomate ACVA WALTER T. McNICHOLAS JR DVM 《Veterinary surgery : VS》1995,24(6):531-534
The effects of intravenously administered atropine (0.2 mg/kg) and glycopyrrolate (0.01 mg/kg) on heart rate were studied in 10 conscious mature goats. In a drug cross-over fashion, either atropine, glycopyrrolate, or 0.9% saline solution was administered using the same volume (0.05 mL/kg). Atropine and glycopyrrolate caused a significant increase in heart rate ( P <.05), whereas saline solution (0.09%) did not. The mean percent changes in heart rate from baseline were similar for atropine and glycopyrrolate up to 14 minutes after administration. Thereafter, glycopyrrolate had a significantly greater mean change in heart rate than atropine, ie, up to 29 minutes ( P <.05). Within the atropine group, the mean percentage changes in heart rate became significantly lower compared with the initial increase (1 minute) starting at 11 minutes. For the glycopyrrolate group, the mean percent changes became significantly lower starting at 27 minutes. Glycopyrrolate and atropine had a mean percentage change in heart rate of greater than 1.0%, up to 31 and 22 minutes, respectively. At the doses used, glycopyrrolate had longer duration of action than atropine but the magnitude of increase was similar. 相似文献
77.
Sudden blindness associated with protothecosis in a dog 总被引:1,自引:0,他引:1
78.
DANNY W. SCOTT WILLARD J. GOULD SUZANNE M. CAYATTE HOWARD J. LAWRENCE WILLIAM H. MILLER JR. 《Veterinary dermatology》1994,5(3):111-115
Resumen— Describimos un caso de alopecia simétrica bilateral en un hurón hembra esterilizada de 3 años. El cuadro resultó estar asociado con un adenocarcinoma adrenocortical y con concentraciones séricas elevadas de estradiol. Además el animal presentaba eritema figurado en la zona dorsolateral, lumbosacra y en la cola con caracteristicas clinicas e histopatológicas parecidas al eritema annulare centrifugum de la especie humana. El eritema figurado se trató con éxito con un producto comercial que contiene el ácido graso omega-3/omega-6. [Scott D. W., Gould, J. W., Cayatte, S. M., Lawrence, H. J., Miller, W. H., Jr. Figurate erythema resembling erythema annulare centrifugum in a ferret with adrenocortical adenocar-cinoma-associated alopecia (Eritema figurado parecido a eritema anulare centrifugum en un hurón con alopecia asociada a un adenocarcinoma adrenocortical).
Abstract— Bilaterally symmetric alopecia and vulvar enlargement is reported in a 3-year-old, spayed female ferret. The condition was ultimately shown to be associated with an adrenocortical adenocarcinoma and elevated serum estradiol concentrations. In addition, the ferret had a figurate erythema over the dorsolateral lumbosacral region and tail that was clinically and histopathologically similar to erythema annulare centrifugum in humans. The figurate erythema was successfully treated with a commercial omega-3/omega-6 fatty acid-containing product. 相似文献
Abstract— Bilaterally symmetric alopecia and vulvar enlargement is reported in a 3-year-old, spayed female ferret. The condition was ultimately shown to be associated with an adrenocortical adenocarcinoma and elevated serum estradiol concentrations. In addition, the ferret had a figurate erythema over the dorsolateral lumbosacral region and tail that was clinically and histopathologically similar to erythema annulare centrifugum in humans. The figurate erythema was successfully treated with a commercial omega-3/omega-6 fatty acid-containing product. 相似文献
79.
CL SCHWARTZKOFF JR EGERTON† DJ STEWART‡ PR LEHRBACH§ TC ELLEMAN¶ PA HOYNE¶ 《Australian veterinary journal》1993,70(4):123-126
SUMMARY A multivalent footrot vaccine has been developed, containing pilus antigens produced in recombinant Pseudomonas aeruginosa and representing all nine serogroups of Dichelobacter (Bacteroides) nodosus commonly recognised in the field. The responses of sheep to the multivalent vaccine have been compared with those to monovalent vaccines representing only a single serogroup. Antigenie competition between serogroups occurred in sheep immunised with the multivalent formulation, but high levels of protection were still achieved. The study showed that in multivalent footrot vaccines, antigenic competition is predominantly due to the presence of a family of immunologically-related pilus antigens rather than to interference by extraneous proteins. 相似文献
80.
Pharmacokinetics of cephalexin in cats after oral administration of the antibiotic in tablet and paste preparations 总被引:2,自引:0,他引:2
Objective To determine the bioequivalence of a paste formulation of cephalexin with that of the tablet form.
Design A two-way cross-over study.
Animals Ten adult cats of mixed breed.
Procedure The cats, randomly allocated to two groups, received either the paste preparation or the tablet orally at 12-hour intervals for 48 h before a 12-hour blood collection period. Two weeks later the treatments were reversed and the blood sampling repeated. The serum concentrations of the antibiotic were determined. The pharmacokinetic factors were analysed using a computer.
Results There were no significant differences between the peak concentration of cephalexin, or the other pharmacokinetic factors obtained from the tablet and paste formulations. The serum profiles of cephalexin following four 12-hourly doses of each formulation were similar with the peak serum values occurring at approximately 2 h after administration.
Conclusion The paste formulation and the tablet form are bioequivalent. 相似文献
Design A two-way cross-over study.
Animals Ten adult cats of mixed breed.
Procedure The cats, randomly allocated to two groups, received either the paste preparation or the tablet orally at 12-hour intervals for 48 h before a 12-hour blood collection period. Two weeks later the treatments were reversed and the blood sampling repeated. The serum concentrations of the antibiotic were determined. The pharmacokinetic factors were analysed using a computer.
Results There were no significant differences between the peak concentration of cephalexin, or the other pharmacokinetic factors obtained from the tablet and paste formulations. The serum profiles of cephalexin following four 12-hourly doses of each formulation were similar with the peak serum values occurring at approximately 2 h after administration.
Conclusion The paste formulation and the tablet form are bioequivalent. 相似文献