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41.
42.
1. The effect of feeding alpha-tocopherol (5 to 180 micrograms/g diet) for 24 days on the concentrations of alpha-tocopherol in various chicken tissues was investigated. 2. Tissue alpha-tocopherol concentrations responded to dietary intake in the order: heart congruent to lung greater than liver greater than thigh muscle greater than brain, and in all cases the relationship between the concentrations of dietary and tissue alpha-tocopherol was highly significant (0.997 less than or equal to r less than or equal to 1). 3. Plasma alpha-tocopherol concentration appears to be a good index (r greater than or equal to 0.910, P less than 0.001) of alpha-tocopherol status of lung, liver and heart.  相似文献   
43.
木材资源国际公司(WRI)是一家位于美国华盛顿州的咨询公司,提供全球木材市场的信息和研究服务。1987年以来,公司已经完成了35个国家的170余个咨询项目。WRI已经同中国木业国际网(China Wood International)共同开展了许多有关木材和木材制品的市场调研项目。我们感到高兴的是中国木业国际网已在从事这个杂志的经营,并且愿意致力于一个定期的栏目,讨论有关中国木材制品的国际贸易方面令人感兴趣的这些问题。这次讨论重点是中国在美国的市场份额持续增长的重要性。  相似文献   
44.
Newly discovered fossils support a Wasatchian (early Eocene) age for the Punta Prieta vertebrate fauna of Baja California and reveal the utility of land mammal ages on a continental scale. Dispersal scenarios for late Paleocene and early Eocene vertebrates usually invoke heterochrony for similar, but geographically separated, faunas or taxa. Such heterochrony is not supported by independent geochronologies or adequate geographic samples.  相似文献   
45.
因为和中国木业国际公司之间亲密的合作.我知道中国木业国际公司正在考虑帮助国内的木产品企业成功地开拓外方市场。那么,在海外买家参观企业的工厂时,怎样给他们留下好的印象呢?我提出如下的建议。请不要认为.这是一个典型西方人提出的中国企业必须照做的建议,我相信这些有助于您的商务。  相似文献   
46.
The aetiological agents of the abdominal swelling affecting farmed larvae of gilt-head seabream, Sparus aurata L., were studied. Four Vibrio strains were isolated from larvae of S. aurata affected by this disease, and all strains reproduced the disease in healthy larvae under controlled infection experiments, producing a significant increase of the mortality rates compared to the control (non-inoculated larvae). Several enzymatic properties, which can act as .virulence factors, were demonstrated both in the extracellular products (ECPs) and In live cells of the strains tested. Histopathological examinations of the infected fish larvae revealed important changes of the anterior intestine and liver characterized by a marked hyperthrophy of the intestinal epithelium and hepatocytes, and by a separation of the mucosal and submucosal layers in the digestive tube. These histological alterations were associated with the constant presence of cocobacillar bacteria in the anterior intestine and in the liver. However, the precise pathogenic mechanisms of the strains tested have not been completely elucidated yet.  相似文献   
47.
本文阐述了猪链球菌病的临床症状、实验室检验及防治方法,力求为科学防控猪链球菌病提供有益的探索和参考。  相似文献   
48.
Lead-salt tunable diode lasers (TDLs) are the only devices currently available that can generate tunable monochromatic radiation at arbitrary wavelengths between 3 and 30 micrometers and are particularly useful for high-resolution spectroscopy over a wide range of spectral regimes. Detailed observations of TDLs show that the observed instrumental linewidth is actually a temporal average of many narrow (less than 0.5 megahertz) emission "modes." The time scale characteristic of these "modes," which appear to be of relatively constant intensity, is of the order of a microsecond. The laser's behavior is highly suggestive of a chaotic process, that is, seemingly random excursions of a dynamic variable (frequency) within a bounded range. This report shows experimentally that TDL emissions are indeed chaotic. Furthermore, in a simple and robust fashion, this chaotic behavior has been successfully controlled with the use of recent techniques that take advantage of chaos to produce a narrow band laser output.  相似文献   
49.
OBJECTIVE: To validate a fat intake questionnaire (FIQ) developed to assess habitual dietary intake while focusing on the assessment of detailed fatty acid intake including total trans unsaturated fatty acids (TUFA). DESIGN: An 88 food item/food group FIQ was developed using a meal pattern technique. Validation was achieved by comparison with dietary intake assessed by a modified diet history (DH) in a cross-over design. Eighty-four individuals supplied adipose tissue biopsies for linoleic acid and total TUFA analysis as an independent validation of the FIQ and DH. SETTING: Medical Centre, Dublin Airport, Republic of Ireland. SUBJECTS: One hundred and five healthy volunteers (43 females and 62 males aged 23-63 years). RESULTS: Significant correlations (P<0.0005) were achieved for intakes of energy (0.78), total fat (0.77), saturated fat (0.77), monounsaturated fat (0.63), polyunsaturated fat (0.73), TUFA (0.67) and linoleic acid (0.71) assessed by the FIQ compared with the DH. Linoleic acid intake assessed by the FIQ and the DH was significantly correlated with adipose tissue concentrations (r=0.58 and 0.49, respectively; P<0.005); however, total TUFA intake was poorly correlated with adipose tissue concentrations (r=0.17 and 0.10 for FIQ and DH, respectively). CONCLUSIONS: The FIQ compared favourably with the DH in assessing habitual diet, in particular fatty acid intake. In addition, the FIQ was successfully validated against the linoleic acid composition of adipose tissue, an independent biomarker of relative fatty acid status. The FIQ could therefore be used as an alternative to the DH as it is a shorter, less labour-intensive method.  相似文献   
50.
HTLV-III in the semen and blood of a healthy homosexual man   总被引:39,自引:0,他引:39  
Human T-lymphotropic virus type III (HTLV-III) is the probable etiologic agent for the acquired immune deficiency syndrome (AIDS). HTLV-III was isolated from semen and blood of a healthy homosexual man whose serum contains antibodies to HTLV-III. The finding of virus in semen supports epidemiologic data that suggest that AIDS can be transmitted sexually. In addition, the demonstration of HTLV-III in the blood and semen of a healthy individual establishes an asymptomatic, virus-positive carrier state which may be important in the dissemination of HTLV-III and, consequently, AIDS.  相似文献   
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