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排序方式: 共有492条查询结果,搜索用时 15 毫秒
91.
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Philip R. Woods DVM PhD Wm. Tod Drost DVM Cyril R. Clarke BVSc PhD Carolyn J. Rodebush RT 《Veterinary radiology & ultrasound》2000,41(1):85-88
Ten healthy horses were injected intravenously with 99mTc-MAG3 and the disappearance of radioactivity from the blood was measured. The total body clearance (Cl(B)) and elimination half-life (t1/2(beta)) were 7.9 +/- 1.5 ml/kg/minute and 32.8 +/- 4.1 minutes, respectively. The disappearance of 99mTc-MAG3 from the blood of 2 horses with compromised renal function was also measured. The data suggest that 99mTc-MAG3 is a useful and clinically applicable radiopharmaceutical for measurement of effective renal blood flow in the horse. 相似文献
94.
Chris M. C. Woods 《Aquaculture (Amsterdam, Netherlands)》2000,190(3-4):377-388
This investigation aimed at improving early juvenile survival in cultured seahorses, Hippocampus abdominalis. Phototaxis from birth until 2 months of age was tested and juveniles were found to be positively phototactic within this age range. A comparison of the effect of culture vessel background (white vs. black vs. clear jars) on feeding efficiency at 1 week and 1 month of age using Artemia as prey revealed an age-dependent effect upon both attack rate and capture success. At 1 week, both attack rate and capture success were higher for juveniles contained in clear jars, and capture success was higher in black jars, as compared with white jars. At 1 month, there was no significant difference in attack rate between different jars, although capture success was higher in clear and white jars than in black jars. In a top-illuminated glass aquarium, juveniles with access to the water surface had lower survival (mean±1 SE=50±4.5%) than those without access to the water surface (73.3±4.2%). This was due to the ingestion of air bubbles when preying on Artemia nauplii congregating near the water surface. For side-illumination there was no such difference. Glass aquaria that were side-illuminated and blacked-off upwards from the waterline supported high juvenile survival (80.4±4.0% per brood) from birth through to 2 months of age in four broods. 相似文献
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96.
Farzaneh Atashrazm Ray M. Lowenthal Gregory M. Woods Adele F. Holloway Joanne L. Dickinson 《Marine drugs》2015,13(4):2327-2346
There is a wide variety of cancer types yet, all share some common cellular and molecular behaviors. Most of the chemotherapeutic agents used in cancer treatment are designed to target common deregulated mechanisms within cancer cells. Many healthy tissues are also affected by the cytotoxic effects of these chemical agents. Fucoidan, a natural component of brown seaweed, has anti-cancer activity against various cancer types by targeting key apoptotic molecules. It also has beneficial effects as it can protect against toxicity associated with chemotherapeutic agents and radiation. Thus the synergistic effect of fucoidan with current anti-cancer agents is of considerable interest. This review discusses the mechanisms by which fucoidan retards tumor development, eradicates tumor cells and synergizes with anti-cancer chemotherapeutic agents. Challenges to the development of fucoidan as an anti-cancer agent will also be discussed. 相似文献
97.
Summary The number of effective factors controlling the inheritance of a quantitative character can be estimated by analysis of F3 lines where the parental lines are homozygous. The procedure is illustrated with data from a study of pod length inheritance in common bean (Phaseolus vulgaris L.). The mean pod length of Sprite, the parent with longer pods, was compared statistically with the means of F3 progenies derived from F2 plants obtained from the appropriate tail of the F2 frequency distribution for pod length. The data indicate that analysis of F3 progenies avoids much of the underestimation of the effective factor number which is characteristic of other procedures. The number of effective factors was estimated to be a minimum of 4 and the correlation between random F2 parents and F3 progeny means was r=0.82.Florida Agricultural Experiment Station Journal Series No. 406. 相似文献
98.
Self-oriented regular arrays of carbon nanotubes and their field emission properties 总被引:4,自引:0,他引:4
S Fan MG Chapline NR Franklin TW Tombler AM Cassell H Dai 《Science (New York, N.Y.)》1999,283(5401):512-514
The synthesis of massive arrays of monodispersed carbon nanotubes that are self-oriented on patterned porous silicon and plain silicon substrates is reported. The approach involves chemical vapor deposition, catalytic particle size control by substrate design, nanotube positioning by patterning, and nanotube self-assembly for orientation. The mechanisms of nanotube growth and self-orientation are elucidated. The well-ordered nanotubes can be used as electron field emission arrays. Scaling up of the synthesis process should be entirely compatible with the existing semiconductor processes, and should allow the development of nanotube devices integrated into silicon technology. 相似文献
99.
J A Weber R T Geary G L Woods 《Journal of the American Veterinary Medical Association》1990,196(7):1084-1089
Ultrasonographic images of the accessory sex glands of 8 stallions were recorded immediately prior to sexual preparation, immediately after sexual preparation, and immediately after ejaculation. Relative size changes, determined by measurements of ultrasonograms of accessory sex gland, were contrasted. Length and width of the bulbourethral glands increased significantly (P less than 0.05) after sexual preparation and decreased significantly (P less than 0.05) after ejaculation. The increase in bulbourethral gland volume following sexual preparation was correlated significantly (P less than 0.01) with the number of false mounts attempted by stallions during sexual preparation. Diameter of the pelvic portion of the urethra did not change significantly (P greater than 0.05) after sexual preparation or after ejaculation. Prostate gland lobular and isthmic thickness increased significantly (P less than 0.05) after sexual preparation and decreased significantly (P less than 0.05) after ejaculation. Total and lumenal diameter of the ampullae increased significantly (P less than 0.05) after sexual preparation and decreased significantly (P less than 0.05) after ejaculation. Diameter of the ampulla wall did not change significantly (P greater than 0.05) after sexual preparation or ejaculation. Reduction of the lumenal area of the ampullae after ejaculation was not correlated (P greater than 0.05) to concentration of spermatozoa or total spermatozoa per ejaculate. Total and lumenal diameters of the vesicular glands increased significantly (P less than 0.05) after sexual preparation and decreased significantly (P less than 0.05) after ejaculation. Diameter of the vesicular gland wall did not change significantly (P greater than 0.05) after sexual preparation or ejaculation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
100.
S Edwards S B Woods D G Westcott M Emmerson P C Jones A J Phillips 《Research in veterinary science》1986,41(3):378-382
More than 300 bovine sera from a previously reported vaccination and challenge trial were tested for antibodies to bovine herpesvirus 1 (BHV1) by five serological assays: enzyme-linked immunosorbent assay (ELISA) for IgM and IgG, passive haemagglutination (PHA), and two methods of virus neutralisation (VN). In a statistical comparison of ELISA (IgG), PHA and VN results, the assays showed highly significant correlations (P less than 0.01). The sensitivities of ELISA and 24-hour neutralisation tests were similar, in contrast to passive haemagglutination and one hour neutralisation which failed to detect BHV1 antibodies in some low titre sera. 相似文献