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排序方式: 共有1076条查询结果,搜索用时 15 毫秒
991.
Yigal Cohen 《Phytoparasitica》1976,4(1):25-31
Of 14 varieties and lines of cucumber and seven of cantaloup tested for resistance againstPseudoperonospora cubensis, only the cucumbers Poinsett and Chipper were found to be highly resistant. Growth chamber studies showed that resistance of young as well as of old (> 8-leaf-stage) plants was stable under considerably high (300 sporangia/cm2) inoculum loads. Resistance was conferred by both restriction of fungal growth and prevention of sporangial formation. 相似文献
992.
Abstract. Mice were injected in the temporal region of the brain with cycloheximide or puromycin; both agents markedly inhibit protein synthesis in the brain. Recordings of electrical activity were made in the hippocampal region 5 hours after injection of these drugs. The amplitude and frequency observed in records from mice injected with cycloheximide were indistinguishable from those injected with saline alone. Records from puromycin-injected mice were strikingly abnormal. This finding may contribute to the differences in behavioral effects of intracerebral injections of the two inhibitors of protein synthesis studied. 相似文献
993.
The melting curve of tintelluride (Sn(0.496)Te(0.504) was determined by differential thermal analysis at pressures between 5 and 40 kilobars. Near 844 degrees +/-4 degrees C and 12.0+/-1.0 kb, the liquid and two solid polymorphscoexist. 相似文献
994.
AIlen J. Roussel DVM MS Noah D. Cohen VMD PhD Walter W. Ruoff DVM MS Gordon W. Brumbaugh DVM PhD David G. Schmitz DVM MS Bruce S. Kuesis DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1993,7(4):241-246
Saline or glucose solution was infused for approximately 4 hours into six healthy mares in two separate experiments to determine the effect of infusion of crystalloid solutions on fractional excretion (FE) of sodium (Na), chloride (Cl), potassium (K), and phosphorus (P), ratio of urinary creatinine to serum creatinine (UCr /SCr ), and ratio of urinary osmolality to serum osmolality (Uosm /Sosm ). After intravenous infusion of either saline or glucose solution, FENa , FECl and FEP were significantly increased, whereas UCr /SCr and Uosm /Sosm were significantly decreased. In addition, FEK was significantly increased after infusion of glucose solution. It was concluded that urinary indices were altered by intravenous infusion of crystalloid solutions in healthy mares and that fluid therapy may interfere with the use of these indices for diagnostic purposes. (Journal of Veterinary Internal Medicine 1993; 7:241–246. Copyright © 1993 by the American College of Veterinary Internal Medicine.) 相似文献
995.
Sleep: suppression of rapid eye movement phase in the cat after electroconvulsive shock 总被引:6,自引:0,他引:6
Electroconvulsive shock, administered for 5 to 7 days, reduced the daily rapid eye movement sleep time of seven cats to as little as 28 percent of base line levels. After day 4, eye movements during periods of cortical activation without tonic electromyographic activity were greatlyreduced. Although partially deprived of rapid eye movements for as long as 7 days, the cats showed no compensatory rise in rapid eye movement time during the recovery period, but controls equally deprived gave significant rebounds. Rapid eye movement time of anesthetized cats was not affected by current that usually produces con vulsions; it was lowered in animals convulsed with metrazol, but the same dosage of this drug, administered so as to avoid convulsions, had little eflect.It appears that some aspect of the convulsion is responsible for lowering the rapid eye movement time. 相似文献
996.
997.
P Cohen 《The Veterinary record》1969,85(21):584-585
998.
Salmonellosis poses a health problem of large proportions in the United States. Annually, it accounts for more than 40,000 reported cases, 500 deaths, and financial costs well in excess of $50 million. Antimicrobial resistance is increasing in Salmonella strains, a finding that has important public health implications. Although the chain of transmission of the bacteria is often complex, combined epidemiologic and laboratory studies with the use of new methods in molecular biology make it possible to trace antimicrobial-resistant salmonellae to their primary source--foods of animal origin. These studies suggest that the antimicrobial drugs to which food animals are exposed provide selective pressure that leads to the appearance and persistence of resistant strains. 相似文献
999.
H Cohen C E Schmidt S R Lucas J L Palmer 《American journal of veterinary research》1975,36(10):1483-1487
Lymphoma developed in 6 neonatal pups inoculated with 1.0 to 2.06 X 10(9) cells of the 2nd in vivo passage of a canine lymphoma. Three to 4 weeks later (or 8 weeks after the pups had been inoculated), 3 of the 6 pups were started on a chemotherapeutic regimen consisting of vincristine, prednisone, and cyclophosphamide. Twelve to 19 days after combination chemotherapy was started, clinically efident lymphoma disappeared in the 3 pups. Period of treatment was 49 to 84 days. The dogs remained healthy and lymphoma was in complete remission approximately 2 years later. The 3 nontreated pups, used as controls, died of generalized lymphoma 45 to 86 days after inoculation. Seemingly, chemotherapy eradicated the bulk of the tumor, and the host immune response was capable of eliminating residual neoplastic cells. Also, transplanted canine lymphoma seems amenable to treatment and may be curable with combination chemotherapy--thus possibly serving as an experimental therapeutic model. 相似文献
1000.
Michael A. Cohen 《Scientia Horticulturae》1978,8(2):163-167
Foliar application of 0.22%–0.68% of sodium 2,3:4,6-di-O-isopropylidene-α-L-xylo-2-hexulofuranosonic acid (Dikegulac-sodium) and Off-Shoot-O (40, 200 p.p.m.) were applied to a number of cultivars of both newly planted and established rhododendron. Treatment with a foliar spray of Dikegulac-sodium increased branching/stem of most cultivars, without affecting shoot length, after 7 weeks. Treatment of Off-Shoot-O was generally not as effective as Dikegulac-sodium. Dikegulac-sodium caused chlorosis of foliage located near the apex after 2 weeks, but this disappeared within 7 weeks after treatment. 相似文献