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131.
The concentration of lysophosphatidylcholine (monoacyl sn-glycerol 3-phosphorylcholine) in intima plus inner media of atherosclerotic aorta from squirrel monkeys was nearly eight times that in comparable control tissue. Plasma levels of the same compound were somewhat elevated in the atherosclerotic group. The metabolism of fatty acyl CoA's and lysophosphatides was studied in cell-free preparations of intima plus inner media from squirrel monkey aorta. Linoleic acid was incorporated predominantly into phosphatidylcholine (as opposed to other phospholipids) when linoleoyl-1-(14)C CoA was the substrate. The extent of this reaction was dependent on the concentration of lysophosphatidylcholine. Lysophosphatidylethanolamine (monoacyl sn-glycerol 3-phosphorylethanolamine) stimulated the incorporation of linoleate into phosphatidylethanolamine. 1-Palmitoyl-1'-(14)C sn-glycerol 3-phosphorylcholine ((14)C-lysophosphatidylcholine) was incorporated into phosphatidylcholine only in the presence of acyl CoA's or ATP plus CoA. Incorporation of (14)C with (14)C-lysophosphatidylcholine plus linoleoyl CoA equaled that with linoleoyl-1-(14)C CoA and lysophosphatidylcholine. Various other lines of evidence are presented to support the importance of the fatty acyl CoA:lysophosphatide fatty acyl transferase mechanism in aortic phospholipid metabolism. Cell-free preparations of aortic intima plus inner media from squirrel monkeys with early, nutritionally-induced atherosclerosis utilized linoleoyl-1-(14)C CoA more than preparations from control monkeys when incubations were carried out without added lysophosphatidylcholine and for long periods (30 min). With optimum levels of labeled linoleoyl CoA and unlabeled lysophosphatidylcholine, or unlabeled linoleoyl CoA and labeled lysophosphatidylcholine, there were no differences in substrate utilization between control and atherosclerotic tissues. We conclude that the concentrations of lysophosphatidylcholine, which are higher in atherosclerotic than in control aortic tissues, could be a factor controlling rates of fatty acid incorporation into phosphatidylcholine.  相似文献   
132.
Cell Walls and Lysis of Mortierella parvispora Hyphae   总被引:1,自引:0,他引:1       下载免费PDF全文
Walls of Mortierella parvispora, Pullularia pullulans, Absidia repens, Fusarium oxysporum, and of several Penicillium species varied in their susceptibilities to digestion by glucanase and chitinase. Polysaccharides were present in the residues remaining after enzymatic digestion. Acid hydrolysates of the walls contained glucose, glucosamine, and a small amount of galactose. The walls of M. parvispora, which also contained fucose, were the least digested by these two enzymes. Much of the M. parvispora wall material was resistant to decomposition by a heterogeneous soil community, and viable hyphae were not lysed by a glucanase-chitinase mixture. Walls of this fungus were fractionated, and the chemical composition of the fractions was determined. The chitin which was abundant in one of the fractions was apparently largely shielded from chitinase hydrolysis by a glucan. The ecological significance of these findings is discussed.  相似文献   
133.
Incomplete phagelike particles were found in competent and incompetent cells of Haemophilus influenzae Rd (transformable) lysed after exposure to ultraviolet radiation.  相似文献   
134.
Zusammenfassung Es wurde fürRubus Gremlii die Chromosomenzahl 2n=28, fürRubus candicans 2n=21 festgestellt. Die Angabe vonMarks fürRubus candicans 2n=35 bezieht sich vielleicht aufRubus Linkianus, der wahrscheinlich mitRubus candicans nicht näher verwandt ist.  相似文献   
135.
Ninety patients who had a recurrence of thyrotoxicosis after thyroidectomy have been reviewed. All 10 patients who had a second operation and 18 out of 20 patients treated with a full course of antithyroid drugs relapsed. These results differ greatly from the results of treatment of the first episode of thyrotoxicosis, whether by thyroidectomy or antithyroid drugs. Radioiodine is the treatment of choice in this group of patients, despite the high incidence of hypothyroidism.  相似文献   
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It has been well established that “normal” pregnancy gives rise to much anxiety whose source is variable. When not adequately dealt with, the anxiety may masquerade in the guise of physical symptoms such as fatigue, dizziness, nausea and vomiting, or, more often, as disquieting emotional counterparts, like irritability and depression.A study was undertaken in the outpatient obstetrical department at U.C.L.A. utilizing a group psychotherapeutic approach. The results helped the patients and offered training to staff in dealing with emotional problems of pregnancy. Patients were seen in groups of seven, twice a month for one-hour sessions. Participating in each group were an obstetrical resident, a psychiatric resident and a nurse. The subject material was not selected beforehand. Groups were similar in that the expected time of delivery of the patients was approximately the same. Results of the study suggested that the much needed emotional support may be supplied in this way with little to no additional time expenditure on the part of the physician or nurse.  相似文献   
140.
SOME CLINICAL LABORATORY BRIEFS ON STAPHYLOCOCCI   总被引:5,自引:0,他引:5  
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