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21.
22.
Cyclic urinary leukopoietic activity in gray collie dogs 总被引:6,自引:0,他引:6
The urinary activities for bone marrow colony formation were measured on consecutive 24-hour urine samples from two gray collie dogs with cyclic neutropenia and from two normal collies. The activity varied cyclically in the gray collies with a peak activity developing during the neutropenic phase, which antecedes the return of blood neutrophils. The activity fell to undetectable levels after the blood neutrophil counts returned to the normal range. The urine of normal dogs showed no activity. Since the dogs with cyclic neutropenia have been shown to have periodic hematopoiesis, these data suggest a regulatory hormonal role for the substance measured by this assay. 相似文献
23.
Ethnic differences in alcohol sensitivity 总被引:14,自引:0,他引:14
P H Wolff 《Science (New York, N.Y.)》1972,175(20):449-450
Japanese, Taiwanese, and Koreans, after drinking amounts of alcohol that have no detectable effect on Caucasoids, respond with a marked facial flushing and mild to moderate symptoms of intoxication. Group differences are present at birth, and are probably related to variations in autonomic reactivity. 相似文献
24.
Abbott RJ Smith LC Milne RI Crawford RM Wolff K Balfour J 《Science (New York, N.Y.)》2000,289(5483):1343-1346
The arctic flora is thought to have originated during the late Tertiary, approximately 3 million years ago. Plant migration routes during colonization of the Arctic are currently unknown, and uncertainty remains over where arctic plants survived Pleistocene glaciations. A phylogenetic analysis of chloroplast DNA variation in the purple saxifrage (Saxifraga oppositifolia) indicates that this plant first occurred in the Arctic in western Beringia before it migrated east and west to achieve a circumpolar distribution. The geographical distribution of chloroplast DNA variation in the species supports the hypothesis that, during Pleistocene glaciations, some plant refugia were located in the Arctic as well as at more southern latitudes. 相似文献
25.
Refojo D Schweizer M Kuehne C Ehrenberg S Thoeringer C Vogl AM Dedic N Schumacher M von Wolff G Avrabos C Touma C Engblom D Schütz G Nave KA Eder M Wotjak CT Sillaber I Holsboer F Wurst W Deussing JM 《Science (New York, N.Y.)》2011,333(6051):1903-1907
The corticotropin-releasing hormone receptor 1 (CRHR1) critically controls behavioral adaptation to stress and is causally linked to emotional disorders. Using neurochemical and genetic tools, we determined that CRHR1 is expressed in forebrain glutamatergic and γ-aminobutyric acid-containing (GABAergic) neurons as well as in midbrain dopaminergic neurons. Via specific CRHR1 deletions in glutamatergic, GABAergic, dopaminergic, and serotonergic cells, we found that the lack of CRHR1 in forebrain glutamatergic circuits reduces anxiety and impairs neurotransmission in the amygdala and hippocampus. Selective deletion of CRHR1 in midbrain dopaminergic neurons increases anxiety-like behavior and reduces dopamine release in the prefrontal cortex. These results define a bidirectional model for the role of CRHR1 in anxiety and suggest that an imbalance between CRHR1-controlled anxiogenic glutamatergic and anxiolytic dopaminergic systems might lead to emotional disorders. 相似文献
26.
E. K. Leonard D. L. Pearl R. L. Finley N. Janecko A. S. Peregrine R. J. Reid‐Smith J. S. Weese 《Zoonoses and public health》2011,58(2):140-149
The purpose of this study was to determine pet‐related management factors that may be associated with the presence of Salmonella spp. in feces of pet dogs from volunteer households. From October 2005 until May 2006, 138 dogs from 84 households in Ontario were recruited to participate in a cross‐sectional study. Five consecutive daily fecal samples were collected from each dog and enrichment culture for Salmonella spp. was performed. A higher than expected number of the dogs (23.2%; 32/138) had at least one fecal sample positive for Salmonella, and 25% (21/84) of the households had at least one dog shedding Salmonella. Twelve serotypes of Salmonella enterica subsp. enterica were identified, with the predominant serotypes being Typhimurium (33.3%; 13/39), Kentucky (15.4%; 6/39), Brandenburg (15.4%; 6/39) and Heidelberg (12.8%; 5/39). Univariable logistic regression models were created with a random effect for household to account for clustering. Statistically significant risk factors for a dog testing positive included having contact with livestock, receiving a probiotic in the previous 30 days, feeding a commercial or homemade raw food diet, feeding raw meat and eggs, feeding a homemade cooked diet, and having more than one dog in the household. In two‐variable models that controlled for feeding raw food, the non‐dietary variables were no longer statistically significant. These results highlight the potential public health risk of including raw animal products in canine diets. 相似文献
27.
Mitteilungen
Mitteilungen aus der Industrie 相似文献28.
29.
The use of ultrasonography in cases of embryo transfer in cattle provides valuable additional information. Indications are the examination of uterus and ovaries, control of superovulation, ultrasound-guided follicle punction for oocyte collecting, pregnancy diagnosis from day 20 and monitoring of early pregnancy for occurrence of embryonic death. Especially the ultrasound-guided follicular aspiration of oocytes seems to be a successful path for a avoiding superovulation. Inhalt: Die Sonographie in der gynäkologischen Diagnostik unter dem Aspekt des Embryotransfers Durch die Sonographie können für Arbeiten in Zusammenhang mit dem Embryotransfer, wie am Beispiel des Rindes gezeigt wurde, wertvolle zusätzliche Informationen erhalten werden. Indikationen für den Einsatz von Ultraschall sind die Funktionsüber-prüfung von Uterus und Ovarien, die Kontrolle der Superovulation, die Oozytengewinnung unter sonographisch überwachter Follikelpunktion mit transvaginalern Zugang, die Graviditätsdiagnose ab dem 20. Tag und die Überwachung der Frühgrauidität, wobei vor allem das frühzeitige Erkennen einer embryonalen Mortalität von Bedeutung ist. Besonders die transvaginale Follikelpunktion zur Oorytengewinnung scheint ein vielversprechender Weg zu sein, wenn eine Superovulation vermieden werden soll oder die betreffenden Tiere aufeine hormonale Stimulation nicht reagieren. 相似文献
30.
This study describes the demographic features of a population of Sigmodon hispidus utilizing the habitat mosaic provided by a Carolina Bay on the Atlantic coastal plain of South Carolina. A total of 71 cotton rats were captured 160 times on a 4 ha grid during a winter decline from 25/ha to less that 1/ha. Body weights of adults declined until early February and then increased; those of subadults grew very slowly until February followed by a spurt in growth. Weight gain did not differ between survivors and non-survivors for males, but female survivors gained 1.5 g per week more than non-survivors. Female subadults exhibited higher mortality early in the decline and males later.Adult females were randomly distributed across 8 microhabitats, whereas adult males were almost exclusively confined to heavy Rubus cover. Subadult males used wet sites more than any other cohort; subadult females were widely distributed using drier sites most frequently. By the end of the decline, all survivors were localized in Rubus-dominated patches. No statistically significant changes in electromorph genotypes or allele frequencies were detected, but survivors had a higher frequency of the F-allele at the adenylate kinase locus than did non-survivors (42.3% vs. 16.7%).Our findings affirm the importance of a landscape perspective in understanding the population dynamics of cotton rats, and show how a habitat mosaic influences survival differentially among sex-age cohorts. 相似文献