Search PubMed⌕ Search

Biomedical subjects

K Murakami

Publications and source records attributed to K Murakami.

At least 1,297 records · Page 72Linked to original sources
PubMed1978

Purine nucleoside phosphorylase from bovine liver.

1. Purine nucleoside phosphorylase (purine nucleoside:orthophosphate ribosyltransferase, E.C. 2.4.2.1) from liver of cattle, Bos taurus, was purified to homogeneity. Some properties of the enzymes from three different bovine tissues were compared and discussed. 2. The enzyme has a molecular weight of 83,000, a sedimentation coefficient of 5.3 S, a Stokes' radius of 3.71 nm, a frictional ratio of 1.30 and a subunit molecular weight of 30,000. 3. Optimal pH for xanthosine degradation is around 5.5, whereas a broad pH activity profile for inosine degradation was observed between 5.0 and 7.5. Lineweaver-Burk plots curved downward at high concentrations of substrates, inosine, phosphate and arsenate.

Animals↗
PubMed1978

The molecular weight and character of plasma renin in SHRSP.

1. The molecular weight was 49,800 in SHRSP, quite different from the 43,300 of WK and the 49,500 and 37,700 of SHR, in females at the age of 200 days. 2. The molecular weight of plasma renin of female WK at the age of 90, 120, and 200 days ranged from 41,000 to 43,000 showing little variation. 3. The molecular weight of plasma renin varied according to the elevation of blood pressure. When blood pressure were 163, 200 to 250, and 267 mmHg, it showed 40,500, about 50,000, and about 60,000, respectively. 4. When subjected to an acid treatment, the high molecular type of SHRSP, showing molecular weights of plasma renin of about 50,000 to 60,000, increased in plasma renin activity by from 1.3 to 4.0 times.

Animals↗
PubMed1978

Surveillance and follow-up of patients with implanted cardiac pacemaker by telephone transmission.

A follow-up study on pacemaker function in 15 patients with implanted cardiac pacemaker has been performed by telephone transmission. The transmitting set consisting of electrocardiograph, pacemaker pulse modulator and acoustic coupler was manipulated by the patients themselves. ECG, pacemaker pulse, and pulse rate were simultaneously transmitted through 1 channel to the receiver in our clinic. Of 56 patients with pacemaker, 15 patients were surveyed by telephone transmission. In these patients battery exhaustion was detected in 3, competition in 2, and lead fracture in 1. The fact that surveillance and follow-up of the patients with implanted cardiac pacemaker could be carried out by telephone transmission as well as by clinic visitation tells us that the telephone transmission is a useful method and plays an important role in a pacemaker clinic. Moreover our study established its further usefulness in the patient's preference due to difficulties in travelling to the pacemaker clinic and in reducing patient's anxiety.

Adolescent↗
PubMed1978

Changes in cell population of Ehrlich ascites tumor by irradiation.

Although irradiated cultured cells undergo a limited number of cell divisions before their death, there exist several evidences that radiation-sterilized cells in solid tumors in animals were eliminated rapidly after irradiation. Experiments were performed to investigate whether rapid elimination of cells is observed in irradiated Ehrlich ascites tumor cells, but it could not be detected. This might be due to the differences of phagocytosis of sterilized cells between solid tumors and ascites tumors.

Animals↗
PubMed1977

Native form of renin in the kidney.

Renin (EC 3.4.99.19) has been observed to exist in a high molecular weight (Mr greater than 50,000) and a low molecular weight from (Mr approximately 42,000) in various tissues. Little is known concerning the origin and function of the high molecular weight form of renin and its relationship to low molecular weight renin. We have found that the high molecular weight form of renin in the kidney was converted to the low molecular weight form during the extraction process. The conversion is apparenly catalyzed by an agent(s) which requires free sulfhydryl groups since blockers of sulfhydryl groups completely suppress the conversion. This conversion could not be prevented by various specific inhibitors of serine proteases nor by the metal chelator EDTA. By the use of Na-tetrathionate it was possible to preserve the renin activity of hog kidney exclusively in the high molecular weight form. Similarly, using N-ethylmaleimide it was shown that a similar high molecular weight form of renin is the exclusive form present in rat kidney. These results suggest that the high molecular weight form of renin is the native form stored in the kidney and that it is converted by an enzyme or agent requiring sulfhydryl groups to the circulating (low molecular weight) form when it is secreted into blood. Renin activity was increased to approximately 155% of the original level upon conversion.

Animals↗