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961.
The effect of phenothiazine derivatives on the thermotropic transition of liposomal lipid bilayer made of dipalmitoyl phosphatidylcholine and dipalmitoyl phosphatidic acid was investigated with differential scanning calorimetry. The thermograms of the liposomal bilayer incorporated with levomepromazine, chlorpromazine, prochlorperazine, perphenazine and fluphenazine were obtained and the size of cooperative unit of the transition were calculated from the ratio of the van’t Hoff enthalpy change to the calculated enthalpy change of the transition. The results showed that incorporation of phenothiazine derivatives into the liposomal bilayer reduced the transition temperature at which the transition from solid state to liquid-crystalline state occurs, and broadened the thermogram peaks. Phenothiazine derivatives also significantly reduced the size of cooperative unit of the transition. The effect of the drugs was proportional to the concentration of the drug in the bilayer. This means that phenothiazine derivatives might have significant fluidizing effects on the biomembrane. The sizes of cooperative unit were successfully correlated with pharmacological activities of the drugs and the surface pressure increases of lipid monolayer by these drugs. These correlations might be ascribed to a possible hydrophobic nature of interaction between the biomembrane and the drugs involved in their pharmacology. 相似文献
962.
Preoperative radiation and surgery for cancer of the rectum. Veterans Administration Surgical Oncology Group Trial II 总被引:13,自引:0,他引:13
In a prospective randomized trial, 361 male patients with histologically proven adenocarcinoma of the rectum, judged preoperatively to require abdominoperineal resection (APR), were treated by surgery alone or were given 3,150 rads of preoperative radiotherapy. Surgical resection was done on 320 patients, 262 having "curative" APR. Only moderate symptoms from radiotherapy were noted and postoperative complications and 30-day mortality were similar in both groups. Five-year survival for curative APR was the same in both groups (50% for both treated and control patients). The incidence of positive lymph nodes in the resected specimens was 35% in treated and 41% in controls. In the first preoperative radiotherapy trial conducted by the group, 5-year survival in patients undergoing "curative" APR was 47% in treated versus 34% in control groups. Additionally, the difference in positive lymph nodes in the resected specimens was substantially greater in the first trial (26% in treated versus 44% in controls). 相似文献
963.
Y W Lee J R Mercer L I Wiebe E E Knaus 《The International journal of applied radiation and isotopes》1984,35(11):1057-1061
3'-Radiohalogenated (36Cl, 82Br and 123I) "arabino" pyrimidine nucleosides were evaluated as potential tumor diagnostic agents in tumor bearing animals. No preferential tissue uptake was observed. The compounds were excreted mainly unchanged in the urine. The 3'-[36Cl]- and 3'-[82Br]-3'-deoxyarabino nucleosides exhibited biliary uptake. The low uptake of injected radioactivity by the tumor was probably due to the combined effects of the lack of a C-3' hydroxyl group in the "ribo" configuration, the presence of a halogen, the structural rigidity imposed by the presence of a halogen and the short biological half-lives of the compounds. 相似文献
964.
965.
Selected testicular enzymes as biochemical markers for procarbazine-induced testicular toxicity 总被引:1,自引:0,他引:1
Single doses of procarbazine (MIH) were injected IP at 0, 50, 100, 200, and 400 mg/kg body weight to CD-1 male mice. Activities of hyaluronidase, lactate dehydrogenase isoenzyme-X, and the dehydrogenases of sorbitol, -glycerophosphate, glucose-6-phosphate, malate, isocitrate, and glyceraldehyde-3-phosphate in the testes of the mice were determined and correlated with changes in spermatogenic cell types in seminiferous tubules. All enzyme activities were higher than controls or remained unchanged on days 10–20 after drug treatment. Activities of hyaluronidase, sorbitol dehydrogenase, and lactate dehydrogenase isoenzyme-X decreased significantly to below normal levels on day 30 after drug treatment for all doses, whereas those of the other five dehydrogenases remained significantly higher than controls. All enzyme activities approached control levels with the concomitant recovery of spermatogenesis by day 60 after drug treatment. Histological examination of seminiferous tubules revealed that premeiotic spermatocytes were significantly reduced on days 10–20 but reappeared on day 30 after MIH treatment (400 mg/kg). The postmeiotic spermatogenic cells were unaffected at the time of MIH treatment, but had disappeared completely on day 30 after drug treatment. MIH, at the highest dosage, selectively destroyed spermatogonia and premeiotic spermatocytes; however spermatozoa and elongated spermatides were unaffected. This study demonstrated that the cytotoxic effect of MIH on spermatogenesis could be evaluated via changes in testicular enzyme activities. The present studies demonstrated that hyaluronidase, sorbitol dehydrogenase, and lactate dehydrogenase isoenzyme-X could serve as useful biochemical markers for assessing testicular toxicity induced by drugs and chemicals. 相似文献
966.
H H Lim Z Domala S Joginder S H Lee C S Lim C M Abu Bakar 《Occupational and environmental medicine》1984,41(4):445-449
A study was carried out to determine the health effects of rice husk dust in Malaysian rice millers. The study population consisted of 122 male Malay workers from three rice mills, with 42 controls of similar age, sex, ethnic group, and agricultural work background. Interviews using standardised questionnaires, physical examination, total and differential white cell counts, chest radiographs, and lung function tests were performed on each of the millers and the controls. Environmental dust monitoring was also carried out in the three rice mills. Clinical, haematological, and radiological findings suggest that a distinct clinical syndrome seems to be associated with exposure to rice husk dust. The manifestations of this "rice millers' syndrome" include acute and chronic irritant effects affecting the eyes, skin, and upper respiratory tract; allergic responses such as nasal catarrh, tightness of chest, asthma, and eosinophilia; and radiological opacities in the chest, probably representing early silicosis or extrinsic allergic alveolitis. 相似文献
967.
Equations are described to derive the true anterior chamber dimensions of an eye from a photograph of its optical section. If the surface of the eye is assumed to be spherical, the three-dimensional coordinates of rays emanating from the anterior chamber to a camera can be transformed to two-dimensional coordinates on a plane, which contains rays both inside and outside of the "eye." The actual dimensions of the anterior chamber then were computed on the basis of the ray tracing over the entire corneal surface. The accuracy of the equations was checked using scales prepared from photographs of curvilinear grids inside an artificial anterior chamber. The advantages of this method are that the true anterior chamber dimensions can be measured in an eye of any corneal curvature and with any type of slit-lamp camera. It appears sufficiently accurate and convenient to be used for clinical and animal studies. 相似文献
968.
Chung Y. Lui Myung G. Lee Win L. Chiou 《Journal of pharmacokinetics and pharmacodynamics》1984,12(6):597-610
The effects of plasma concentration and pH on the steady-state volume of distribution, Vss,of methotrexate (MTX) were studied in five conditioned male beagle-mongrel dogs. Steady-state plasma MTX concentrations of approximately 1, 20, and 100g/ml were targeted for by i.v. bolus doses followed by i.v. infusions. An isotonic solution of sodium bicarbonate or ammonium chloride was simultaneously infused for the purpose of inducing plasma pH change, while the infusion of an isotonic solution of sodium chloride served as a control. Plasma and urine concentrations of MTX were quantitated by a sensitive high-performance liquid chromatographic method, and the Vss
of MTX was estimated by a recently reported physiologically based method of Chiou and Lam. Statistically significant (p<0.05) concentration and plasma pHdependent Vss
of MTX were observed. Concentration dependence of Vss
was noted in sodium chloride and ammonium chloride infused dogs, but not in bicarbonate treated dogs. There was an average 50.0 and 44.8% increase in Vss
at 1 g/ ml relative to the two higher concentrations (20 and 100 g/ ml) for dogs treated with ammonium and sodium chloride, respectively. However, Vss
of MTX at the targeted concentrations of 20 and 100 g/ml was relatively constant. Plasma pHdependence of Vss
was observed only at the plasma concentration of 1 g/ml, and on the average, ammonium chloride and sodium chloride treatments resulted in 50.0 and 31.3% higher Vss,respectively, when compared with the bicarbonate treatment. These phenomena appear to be adequately explained by the reported tissue uptake kinetics of MTX.This research was supported in part by a grant from the National Cancer Institute, CA-29754.Abstracted from a dissertation submitted in 1984 by Chung Y. Lui to the Graduate College, University of Illinois at Chicago, in partial fulfillment of Doctor of Philosophy Degree requirements. 相似文献
969.
Relational continuity of care (COC) is becoming an important concept related to improving healthcare quality, reducing medical costs and increasing patient satisfaction with primary care. While community pharmacy (CP) has a considerable role in primary care, there are few reports dedicated to the role of relational COC in CP. This study reviewed the existing evidence of relational COC in CP and its effect on patients. PubMed, Embase, CINAHL, Cochrane Library CENTRAL and Google Scholar were used to search for relevant studies from the date of database inception through to January 2021, which were appraised according to eligibility criteria. There were no limitations on the primary outcome or language. Case reports and studies without control groups were excluded. The Newcastle–Ottawa quality assessment scale was used to assess the quality of the studies. Database searches identified 13 records. Relational COC measures in the included studies were grouped in three kinds; pharmacy-visiting pattern, Continuity of Care Index and loyalty. The assessed outcomes were medication adherence behaviour (e.g., the proportion of days covered, medication possession ratio), adverse drug reactions, potentially inappropriate drug prescribing and clinical outcomes. The odds of patients adhering to their medication regimen were about 1.1~2.5 times higher among those who consistently visited a single pharmacy compared to patients visiting multiple pharmacies. Additionally, the care provision with a high level of relational continuity could lower inappropriate drug use by 21~32 per cent and the use of other costly services by 12~29 per cent. This study suggests that a high degree of relational COC in CP could improve safe use of medications among patients. Future research is needed to employ more rigorous methods to reduce heterogeneity and to measure effects on clinical outcomes. 相似文献
970.
Journal of Public Health - The present study aimed to examine the effects of primary social factors on the smoking behaviors according to the smoking stages—initiation and... 相似文献