Individual variability in sucrose consumption is prominent in humans and other species. To investigate the genetic contribution to this complex behavior, we conducted behavioral, electrophysiological, and genetic studies, using male progeny of two inbred mouse strains (C57BL/6ByJ [B6] and 129/J [129]) and their F2 hybrids. Two loci on Chromosome (Chr) 4 were responsible for over 50% of the genetic variability in sucrose intake. These loci apparently modulated intake by altering peripheral neural responses to sucrose. One locus affected the response threshold, whereas the other affected the response magnitude. These findings suggest that the majority of difference in sucrose intake between male B6 and 129 mice is due to polymorphisms of two genes that influence receptor or peripheral nervous system activity. 相似文献
In Japanese, serum cholesterol levels have been increasing. This seems to be due to changes in life style, mainly the increase in dietary fat. Epidemiologic studies in the United States and Europe have shown that patients with hypercholesterolemia have a high risk of ischemic heart disease. Some guidelines for the management of hyperlipidemia have been developed in the United States, Europe, and Japan. The National Cholesterol Education Program (NECP) in the United States divides serum cholesterol level into three grades (desirable: below 200 mg/dl, borderline: between 200 mg/dl and 240 mg/dl, hypercholesterolemia: over 240 mg/dl). Borderline serum cholesterol is also a risk, especially in people complicated by other risk factor(s). As most borderline serum cholesterol seems to be due to polygenic hypercholesterolemia, an attempt to change the diet should be the first recommendation for treatment. 相似文献
A case of bilateral congenital aplasia of the carpal scaphoid bone is presented. In contrast to previously reported cases of congenital hypoplasia of the scaphoid, this case was not associated with hypoplasia or absence of thenar and forearm muscles, absence of the sesamoid bones of the thumb, abnormalities of the skeleton of the thumb ray or hypoplasia of the forearm bones. 相似文献
The limit of detection (LOD) and range of quantitation (ROQ) of competitive enzyme-linked immunosorbent assay (ELISA) were determined from a model describing the calibration curve and precision profile of the assay. The calibration curve is given by solving the differential equations describing the change in the concentrations of an antigen-antibody complex and an enzyme-conjugated antigen-antibody complex by a Runge-Kutta method. The precision profile is described in terms of possible error sources such as the pipetting volumes of the analyte, enzyme-conjugated antigen, antibody and substrate solutions, calibration curve and inherent absorbances between the wells in an ELISA plate. An appropriate concentration of the enzyme-conjugated antigen that balances a low detection limit and sufficient color development was found to be in a narrow range, which is consistent with the empirical rule. The optimum conditions for competitive ELISA using an antibody with a kinetic property can be designed from our model. 相似文献
Naphthoquinones are considered privileged structures for anticancer drug molecules. The Heck reaction of 2‐hydroxy‐1,4‐naphthoquinone (lawsone) with 1‐bromo‐3‐methyl‐2‐butene offered easy access to lapachol. Several naturally occurring linear and angular heterocyclic quinoids (α‐lapachone, β‐lapachone, dunnione, and related analogues) were prepared from lapachol. Furthermore, we demonstrated that the synthetic naphthoquinones inhibit cell proliferation in human leukemia HL‐60 cells. In particular, angular‐type derivatives were found to possess moderate cytotoxicity and to elevate the levels of intracellular glutathione disulfide (GSSG). Our work highlights the significant potential of naturally occurring angular‐series naphthoquinones as antileukemic agents. 相似文献
Analyses on the gas dispersion from a vent mast have been conducted using fire dynamics simulator (FDS) for a 50000 dead weight tonnage (DWT) gas-fueled bulk carrier, under the assumption that methane and propane gases are discharged through a pressure relief valve in the vent system of the fuel storage tank. To assess the transient flammable extents for representative vent scenarios, the initial conditions of venting gases were selected as propane at–30 °C and methane at–150 °C, when wind velocity was set to 2 m/s in the ship exterior. The same ship layout was applied in each of these scenarios with different configurations of the inner components of the vent mast outlet. As a result, the cases with a plate head in the current vent mast outlet did not satisfy international code requirements for the safety distance of the vent mast location in ships powered by low-flashpoint fuels. However, the flammable extents of the venting gases could be significantly reduced by a novel vent system in which a swirl head and nitrogen diluent at 20 °C were adopted. Therefore, a safety design procedure considering gas dispersion characteristics was required to determine the location of the vent mast outlet in the gas-fueled vessel to satisfy the minimum requirements of the international code.