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41.
DJ Hentges BR Maier GC Burton MA Flynn RK Tsutakawa 《Canadian Metallurgical Quarterly》1977,37(2):568-571
Ten human volunteers completed a 4-month diet series consisting of 1 month each of a control diet, a meatless diet, a high-beef diet, and the same control diet. Fat and fiber contents were essentially the same in all four diets, but protein content was doubled during the high-beef diet. During the 4th week on each diet, three stool specimens collected from each volunteer were analyzed for chemical composition and content of facultative, aerobic, and anaerobic bacteria. The bacteriological data are presented in this paper. High beef protein consumption had little effect on the composition of the intestinal flora. There were no significant differences in total counts of facultative and aerobic or anaerobic organisms in the feces when volunteers were on meatless or high-beef diets. At the species level, when counts during the two control diets were comparable, in only three instances did the change from the meatless to a high-beef diet significantly influence the bacterial numbers. The ratio of mean counts of anaerobic to facultative and aerobic organisms was approximately 15:1 during the meatless diet and 34:1 during the high-meat diet. The data indicate that animal protein consumption has little effect on the fecal bacterial profile in humans. 相似文献
42.
MD Adams JT Earnhardt BR Martin LS Harris WL Dewey RK Razdan 《Canadian Metallurgical Quarterly》1977,33(9):1204-1205
Abnormal-delta8-tetrahydrocannabinol (ABN-delta8-THC) failed to elicit central nervous system and cardiovascular effects in laboratory animals. Abnormal-cannabidiol (ABN-CBD) was also devoid of overt behavioral effects but produced marked hypotension with only slight bradycardia in anesthesized dogs. 相似文献
43.
BD Strahl HJ Huang J Sebastian BR Ghosh WL Miller 《Canadian Metallurgical Quarterly》1998,139(11):4455-4465
44.
JM Mariner JB McMahon BR O'Keefe K Nagashima MR Boyd 《Canadian Metallurgical Quarterly》1998,248(3):841-845
Concentrations of the potent, HIV(human immunodeficiency virus) inactivating protein, cyanovirin-N (CV-N), which completely inhibit HIV-1 infectivity, do not block the binding of soluble CD4-receptor (sCD4) to HIV-1 lysates nor the attachment of intact HIV-1 virions to several target T-cell lines. Furthermore, in contrast to the known disassociative effects of sCD4 on viral envelope glycoproteins, treatment of HIVRF with high concentrations of CV-N results in complete viral inactivation but without apparent shedding of gp120 or other ultrastructural changes. These results are consistent with the view that the virucidal effects of CV-N result from interference with step(s) in the fusion process subsequent to the initial binding of the virus to target cells. 相似文献
45.
BR Berends F Van Knapen DA Mossel SA Burt JM Snijders 《Canadian Metallurgical Quarterly》1998,44(3):219-229
Cell-cell and cell-extracellular matrix interactions are fundamental processes involved in cell migration and tissue remodeling. Both the cyclic regeneration of the human endometrium during the menstrual cycle as well as the process of embryo implantation involve such dynamic interactions. It has become quite clear that integrin adhesion molecules expressed on the surface of cells play critical roles in the transmission of signals from the extracellular milieu to the cells. It is these signals that presumably regulate the behavior of these cells during major morphogenetic processes. In recent years, work in human endometrium and trophoblasts has uncovered both the regulated and constitutive expression of integrin subunits and their extracellular matrix ligands in these tissues. In addition, attempts have been made to correlate pathological states related to either infertility or abnormal pregnancy to the aberrant expression of several of these integrins. The purpose of the present review is to describe briefly our present state of knowledge of the expression of integrins in human endometrium and trophoblasts and provide the reader with the necessary background needed to understand, at the cellular and molecular levels, processes in reproduction such as embryo implantation. 相似文献
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48.
Troxel D. Schreiber W. Bishop R. Buckley R. Bunza G. Eguchi T. Goldwasser S. Jakubson J. Jung-Shu Kung Ng D. Takemoto S. Yokoyama E. 《Communications, IEEE Transactions on》1981,29(12):1841-1848
The two-channel system previously reported has been implemented in hardware using system parameters appropriate to consumer television. The basic system divides the spectrum into lowand high-frequency spatial components. The lows are coarsely sampled and finely quantized and the highs finely sampled and coarsely quantized using a companded, randomized quantizer. The purpose of this experiment was to demonstrate the potential of the system for low-cost practical application, to study the effect of the character of the randomizing noise, and to ascertain that there were no deleterious effects due to interlace, motion, or input noise. Theoretical noise calculations were qualitatively confirmed. 相似文献
49.
50.
A novel toroidal cross capacitor was used to measure accurately the dielectric polarizability(p) (i.e., the dielectric constant as a function of the pressure) of helium, argon, nitrogen, methane, and carbon dioxide atT=50°C. The data extend up to 7 MPa (5 MPa for CO2) and may be useful for calibrating on-line, capacitance-based systems that are designed to measure the heating value of natural gas. The uncertainties ofandpare 4×10–6and (3.0×10–5
p+84 Pa), respectively. The properties of helium that had been calculatedab initiofrom quantum mechanics were used to verify that the cross capacitor deformed in a predictable manner under hydrostatic (gas) pressure. Thus, a common cause of systematic errors in measuring the dielectric constant of gases was avoided. For helium, the rms deviation of(p) from the calculations was only 2.7×10–7. This suggests that the estimated uncertainty is very conservative. 相似文献