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91.
92.
S B Cheknev O L Latysheva L A Denisov F I Ershov 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(2):179-182
The cytotoxic activity of natural killer (NK) cells isolated from peripheral blood of 20 healthy donors and 34 patients with multiple sclerosis (MS) against labelled with H3-uridine target cells K-562 before and after their 1 hr treatment with reaferon (RF), T-activin (TA), myelopid (MP), opioid preparation dalargin (DL) as well as with combinations of TA, MP and DL with RF was studied in 14 hrs cytotoxic test. It has been shown that combination of RF with TA, MP and DL changed the regulatory action of these peptides on NK cell activity in healthy donors in vitro. The same combination of the preparations in patients with MS caused another changes in regulation of NK activity by them because NK cells in MS patients had had initially changed sensitivity to action of these regulatory polypeptides. 相似文献
93.
Iu V Ladilov B I Islamov S I Vorob'ev G R Ivanitski? 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(6):593-595
The effect of different doses of perfluorocarbon emulsion (5, 10, and 15 ml/kg) on the hemodynamics and contractility of heart was studied on anesthetized dogs. The emulsion was introduced intravenously by the 60th minute of acute myocardium ischemia caused by partial coronary occlusion. When pO2 = 120 mm Hg, the emulsion was efficient only at doses of 10 and 15 ml/kg (an increase in cardiac ejection, in the rate of contraction and relaxation of the myocardium, reduction of vascular resistance). However, the efficiency of the emulsion at a dose of 15 ml/kg was lower, possibly, due to hypervolemia and cardiodepressive effect of introduction of excess quantity of the surface-active substance proxanol, a component of the emulsion. 相似文献
94.
Isabel Bandín Ysabel Santos Beatriz Magariños Juan L. Barja Alicia E. Toranzo 《FEMS microbiology letters》1992,94(1-2):105-110
The analysis of the membrane proteins and their antigenic properties in a group of 14 geographically diverse strains of Renibacterium salmoninarum revealed the existence of antigenic diversity within this species. Eleven isolates, including the type strain ATCC 33209, shared a similar protein profile with a major component of 57 kDa whereas three strains showed a common pattern with a major protein of 30 kDa. The quantitative agglutination tests and Western blotting assays seem to indicate the existence of serological heterogeneity, with two distinct groups being detected. 相似文献
95.
96.
T F Fehr E S Dickinson S J Goldman L L Slakey 《The Journal of biological chemistry》1990,265(19):10974-10980
Cultured pig aortic smooth muscle cells respond to extracellular adenosine by activating adenylate cyclase and by initiating the efflux of cAMP. In the presence of extracellular adenosine, efflux is first order with respect to intracellular cAMP concentration up to at least 125 pmol/10(6) cells. The apparent first-order rate constant for the efflux of cAMP increases in a dose-dependent manner in response to extracellular adenosine or 5-N-ethylcarboxamide adenosine. The EC50 for adenosine for promoting cAMP efflux is 12 microM. For cells stimulated with 5-N-ethylcarboxamide adenosine, the EC50 is 5 microM. When extracellular adenosine is removed, efflux stops abruptly. Cellular cAMP content falls but is still in a range that supports cAMP efflux when agonist is present. Efflux is not affected by H8 (N-[2-(methylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride), an inhibitor of cAMP-dependent protein kinase. These data suggest that in pig aortic smooth muscle cells, the efficiency of cAMP efflux is regulated by A2 receptor occupancy. 相似文献
97.
R K Daniel J Hodgson V S Lambros 《Plastic and reconstructive surgery》1990,85(6):859-66; discussion 867-8
The physical characteristics of the light reflexes of the nasal tip are defined in large part by the studio lighting configuration. By varying the lighting configuration, it is possible to alter the light reflexes as regards their number, distance apart, symmetry, and size. For the plastic surgeon, the quarter light system of the medical photographer has definite advantages over the key light system of the portrait photographer. The quarter light system consists of two lights of equal intensity with symmetrical angles of incidence placed at 45 degrees to the camera-subject axis. Measuring changes in the light reflexes as a method of determining the efficacy of surgical techniques is valid under very controlled conditions. 相似文献
98.
Iu M Lopukhin A G Sdvigova T I Torkhovskaia Zh I Kliuchnikova M K Evstigneeva E M Khalilov 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(5):476-478
Therapeutic effect of corn oil was studied in rabbits with alimentary atherosclerosis. Corn oil was administered (2 ml/kg, 30 days) after the completion of cholesterol diet unlike studies, where they were administered simultaneously. Total cholesterol, apoB-lipoprotein cholesterol and triglycerides decreased more intensively in rabbits fed by corn oil than in control group. No changes in high-density lipoprotein cholesterol were observed. The most pronounced effect was noted in aorta morphological analysis: an aorta damage degree was 4.8% as compared with 52.9% in the control group. The results show that available plant oils with omega-6 polyunsaturated fatty acids (PUFA), in particular corn oil, may as well as omega-3 PUFA be used as the base for antiatherogenic preparations. 相似文献
99.
Urine testing for drug use in the workplace is now widespread, with the prevalence of positive drug tests in the work force being 0% to 15%. The prevalence of marijuana use is highest, and this can be reliably tested. Though it is prudent to rid the workplace of drug use, there is little scientific study on the relationship of drug use and workplace outcomes, such as productivity and safety. Probable-cause testing and preemployment testing are the most common applications. Random testing has been less accepted owing to its higher costs, unresolved legal issues, and predictably poor test reliability. Legal issues have focused on the right to policy, discrimination, and the lack of due process. The legal cornerstone of a good program is a policy that is planned and agreed on by both labor and management, which serves both as a contract and as a procedure in which expectations and consequences are known. The National Institute on Drug Abuse is certifying laboratories doing employee drug testing. Testing methods when done correctly are less prone to error than in the past, but screening tests can be defeated by adulterants. Although the incidence of false-positive results is low, such tests are less reliable when the prevalence of drug abuse is also low. 相似文献
100.
Stimulation of CTP: phosphocholine cytidylyltransferase and phosphatidylcholine synthesis by incubation of rat hepatocytes with phospholipase A2 总被引:1,自引:0,他引:1
The effect of phospholipase A2 treatment of rat hepatocytes on CTP: phosphocholine cytidylyltransferase and phosphatidylcholine synthesis was investigated. Cytidylyltransferase is recovered from the cytosol and in a membrane-bound form with the microsomes. Digitonin treatment of cells causes rapid release into the medium of the cytosolic, but not the microsomal form of the cytidylyltransferase. Incubation of hepatocytes for 10 min with phospholipase A2 (0.9 units/dish) in the medium, resulted in a 33% decrease in the cytidylyltransferase activity released by digitonin treatment (2.5 +/- 0.15 nmol/min per mg compared to 3.9 +/- 0.10 nmol/min per mg in the control). In agreement with the digitonin experiments, incubation with 0.9 units/dish of phospholipase A2 resulted in a decrease in the cytidylyltransferase activity in the cytosol (from 4.3 +/- 0.10 nmol/min per mg to 2.6 +/- 0.14 nmol/min per mg) and a corresponding increase in the microsomal fraction (from 0.9 +/- 0.16 nmol/min per mg to 1.8 +/- 0.20 nmol/min per mg). The effect of phospholipase A2 on cytidylyltransferase translocation was concentration- and time-dependent. Incubation of hepatocytes in the presence of phospholipase A2 (0.9 units/dish) for 10 min prior to pulse-chase experiments resulted in an increase in radiolabel incorporation into phosphatidylcholine (from 2.4 +/- 0.02.10(-5) dpm/dish to 3.1 +/- 0.1.10(-5) dpm/dish) and a corresponding decrease in radiolabel associated with the choline (from 2.5 +/- 0.05.10(-5) to 1.4 +/- 0.03.10(-5) dpm) and phosphocholine fractions (from 8.5 +/- 0.07.10(-5) to 6.9 +/- 0.05.10(-5) dpm). We conclude that phospholipase A2 can cause a stimulation of CTP: phosphocholine cytidylyltransferase activity and phosphatidylcholine synthesis in cultured rat hepatocytes. 相似文献