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141.
The ATPase assay system on pH stat apparatus was developed. For the ATPase activity measurement, hydrogen ion (H+) concentration delivered from inorganic phosphate (Pi) as a hydrolysis production of ATP was estimated by titrating with 20 mM NaOH solution instead of colorimetric measurement of Pi. Inclusion of 0.5 M KCl in the ATP stock solution and 2 mM Tris-maleate (pH 7.0) buffer in the reaction medium reduced the extent of pH change upon addition of ATP to initiate the ATPase reaction. The amount of H+ liberated from Pi was strongly affected by the set pH for the ATPase assay with a promotion at alkaline pH. Thus, it was required to estimate the coefficient to convert H+ to a Pi concentration at a specific pH. The specified coefficient at pH 7.0 was 1.248. ATPase assay on pH stat allowed us to follow the ATP hydrolysis by myofibrils continuously showing a curvature profile at low salt medium (≤0.2 M KCl) or a linear profile at high salt (≥0.3 M KCl).  相似文献   
142.
ABSTRACT: Four new bromophenols and a known bromophenol derivative have been isolated from the Palauan sponge Phyllospongia dendyi . The structures of these new compounds were established using nuclear magnetic resonance and mass spectral data. They showed antimacroalgal activity with IC50 values of 0.02–0.05 p.p.m. Moreover, all compounds were antimicroalgal against various classes of algae at concentrations of 0.5–5.0 p.p.m.  相似文献   
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A 10‐year‐old castrated male miniature dachshund was presented with an abdominal mass. The dog had a history of splenectomy. Triple‐phase helical computed tomography was utilized, revealing a hepatic mass and multiple intra‐abdominal solid masses. In triple‐phase helical computed tomography the images, hepatic mass and two of four intra‐abdominal masses were heterogenous in all phases. Therefore, we diagnosed a malignant hepatic tumor and presumed intra‐abdominal metastases. The masses were surgically removed and were histologically composed of normal spleen tissues, findings which were consistent with ectopic spleen.  相似文献   
146.
To elucidate relationship between disease progress and immunologic alteration in feline immunodeficiency virus (FIV) infection, we classified naturally infected cats into clinical stage groups using the working criteria modified from those for human immunodeficiency virus (HIV) infection. Among the five distinct stages described for HIV infection, the three phases; asymptomatic carrier (AC), AIDS related complex (ARC), and acquired immunodeficiency syndrome (AIDS), were evaluated for concanavalin A (Con A)-induced lymphocyte blastogenic activities by using glucose consumption assay. There was a significant decrease of lymphocyte response in AC phase. The loss of response became marked as the disease progressed to ARC and AIDS, with an almost complete loss of mitogen response in AIDS phase. In addition to the loss of a lymphocyte function, AIDS in FIV infection was characterized by marked emaciation, anemia or pancytopenia, and postmortem evidences of opportunistic infections and lymphoid depletion.  相似文献   
147.
This study investigated an objective method for estimating beef marbling using ultrasonic images of the Iliocostalis muscle and the Lomgissimus muscle area sections. Thirty‐one Japanese Black cattle steers were used in this study. The end of the left side shoulder blade bone was scanned using an ultrasonic device. Ultrasonic images were captured of the Longissimus muscle area and that around the Iliocostalis muscle area. Twenty items were measured in the two images using computer image analysis software. The level of beef marbling was measured according to the Beef Marbling Standard (BMS) for carcass grading, and the percentage of ether‐extractable fat content in the Longissimus muscle (EE). The difference in the gray level between the Iliocostalis muscle and intermuscular fat (X10) was used to estimate the BMS and the EE, which were highly correlated (r2 = 67.72% and 61.30%). An equation was developed using four parameters from the two ultrasonic images, which could estimate the BMS (r2 = 85.88%). This equation could also estimate the EE (r2 = 68.98%). The equations used to estimate beef marbling were based on one to four parameters that included X10. Thus, ultrasonic images of the Iliocostalis muscle area section are important for estimating beef marbling.  相似文献   
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