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91.
92.
Summary The effects of oral dilevalol (an R, R-isomer of labetalol), a new -adrenoceptor blocker with 2-receptor stimulating and -recepter blocking properties on blood pressure, renal function, plasma renin activity (PRA) and plasma aldosterone have been studied in 15 patients with mild-to-moderate essential hypertension treated with it for 6 weeks.Two patients with apparent treatment failure and one patient who developed muscle pain and cramps, and had an elevated creatine phosphokinase level, were excluded from the study.Dilevalol monotherapy 100 mg once daily for 6 weeks significantly lowered both the systolic and diastolic blood pressure compared to placebo. Total renal vascular resistance was significantly reduced, and RBF and GFR remained unchanged. Dilevalol significantly decreased PRA.The results suggest that prolonged daily treatment with dilevalol preserves renal function and produces a concomitant hypotensive action in patients with mild-to-moderate essential hypertension. The ancillary pharmacological properties of dilevalol rather than PRA suppression may be relevant to its renal effects.  相似文献   
93.
Summary The effects of opioids on the permeability of the blood-brain barrier (BBB) were examined in mice with sodium fluorescein as an indicator of the permeability. The brain was perfused with saline 30 min after injection of sodium fluorescein (40 mg/kg, i. v.) and examined by fluorometry. Morphine hydrochloride (0.3–10 mg/kg, s. c.) markedly increased the brain level of sodium fluorescein dose-dependently without influencing the plasma level, when administered 20 min before sodium fluorescein injection. Intracerebroventricularly (i. c. v.) injected morphine hydrochloride (0.5 and 1.0 Erg) increased the brain sodium fluorescein level. Buprenorphine (0.1 and 0.5 mg/kg, s. c.) was also effective. However, pentazocine, ethylketazocine, U-50488H and SKF-10047 had no significant influence. The i.c.v. administration of [D-Ala2, McPhe4, Gly(ol)5]enkephalin (0.1 g) and [D-Ala2, D-Leu5]enkephalin (0.5 g) but not of [D-Thr2, Leu5]enkephalin-Thr increased the brain level of sodium fluorescein significantly. A small dose of naloxone (i. p.) significantly inhibited the effects of morphine, buprenorphine, [D-Ala2, McPhe4, Gly(ol)5]enkephalin and [D-Ala3, D-Leu5]enkephalin. ICI-174864 co-administered i. c. v. with [D-Ala2, D-Leu5]enkephalin was ineffective in antagonizing the effect of the latter. These findings suggest that the stimulation of µ opioid receptors results in an increase in BBB permeability to sodium fluorescein. Send offprint requests to K. Saeki  相似文献   
94.
The interactions of acidic and basic drugs with 1-acid glycoprotein (1-AGP) were investigated using circular dichroism (CD) measurements. Extrinsic Cotton effects were generated by the binding of drugs to 1-AGP. The CD data suggested the presence of a single binding site on the 1-AGP molecule. The induced ellipticities of the acidic drug–1-AGP system decreased with increasing pH, while the ellipticities for the basic drugs increased with pH. The ellipticities for all drugs were reduced by the addition of fatty acids. Furthermore, the induced ellipticities decreased in the presence of cesium chloride for basic drugs bound to 1-AGP. The extrinsic Cotton effects therefore appear to result from hydrophobic interaction with 1-AGP for the acidic drugs and from hydrophobic and electrostatic interactions for the basic drugs.  相似文献   
95.
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 1971–1975 to 62.3%during 1981–1985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 1971–1975and 69.7% during 1981–1985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 37–40 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe.  相似文献   
96.
We previously reported the expression profiles of 9 cytochrome P450 isozymes (CYPs) proteins and those of 40 CYPs genes in pregnant rat's liver, placenta and fetal liver after treatment with pregnenolone-16alpha-carbonitrile (PCN) or phenobarbital (PB). This study was carried out focusing on the gene expression profiles of Phase II drug metabolizing enzymes, Glutathione S-transferase isozymes (GSTs) and UDP-glycosyltransferase isozymes (UDPGTs). Fischer 344 (F344) pregnant rats were daily treated intraperitoneally with 50 mg/kg of PCN or 80 mg/kg of PB from 13 to 16 days of gestation (DG). They were sacrificed on 17 DG, and microarray analysis using Affymetrix Rat Expression Array 230 A was performed. Among 16 GSTs genes examined in this study, 7 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 8 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. On the other hand, among 11 UDPGTs genes examined, 5 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 5 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. There were no significant changes in the placenta of all groups. This is the first report of the gene expression profiles of Phase II drug metabolizing enzymes in pregnant rat and fetal livers and placenta after treatment with typical inducers of drug metabolizing enzymes.  相似文献   
97.
Recent data have shown the existence of specific changes in mRNAs in thyroid carcinomas. It has not been clarified, however, why these changes clearly distinguish benign tissues from carcinomas, while genomic alternation such as mutations in the RAS or P53 genes do not. Further, the widely believed hypothesis, multi-step carcinogenesis, does not explain some clinical and experimental evidence of thyroid carcinomas. Considering these facts, we propose a new idea for thyroid carcinogenesis called "germ-cell carcinogenesis", in which cancer cells are derived from the remnant of fetal thyroid germ cells(thyroblasts) instead of normal thyroid follicular cells. Utilizing such mRNAs, we have established a new method for preoperative molecular-based diagnosis of thyroid carcinomas, Aspiration Biopsy Nucleic Acid Diagnosis(ABND). ABND allows us to perform preoperative nucleic acid analyses of the tumors by extracting RNAs or DNAs from tumor cells obtained by fine needle aspiration biopsies(FNABs). Pathological diagnosis of thyroid follicular carcinoma is quite difficult, and the establishment of preoperative molecular-based diagnosis of follicular carcinoma has been long expected. We found that quantification of the trefoil factor 3(TFF3)/galectin-3 mRNA ratio in thyroid tumor cells is a useful tool for distinction between follicular adenomas and carcinomas. Because ABND can be performed without any severe invasion to the patients, in the near future, when more reliable systems of quantitative RNA analysis have been developed, ABND will probably become one of the standard tests for preoperative diagnosis of thyroid carcinoma.  相似文献   
98.
In human testis, expression of a novel member of the aldo-keto reductase family was identified. Based on its testis-specific expression, we termed this protein human testis aldo-keto reductase (htAKR). In addition to four major isoforms, the existence of multiple alternatively spliced products of htAKR was detected using RT-PCR followed by nested PCR. htAKR was a homologue of mouse liver keto-reductase, AKR1E1, with close similarity in their genomic organizations. htAKR4, the longest isoform, was expressed as a non-fused native form. It exhibited a limited activity toward 9,10-phenanthrenequinone, while no activity toward the steroids or prostaglandins was demonstrated. Using the laser capture microdissection technique and RT-PCR, expression of htAKR was detected in testicular germ cells as well as in interstitial cells. The levels of htAKR mRNA in the tissues obtained from seminoma were much lower than those in normal testes. A significant decline in the htAKR expression was observed when NEC8, a cell line originated from a human testicular germ cell tumour, was exposed to phorbol 12-myristate 13-acetate or 5alpha-dihydrotestosterone. These results indicate that the expression of htAKR, down-regulated in the testicular tumour, is possibly controlled by mitogenic and hormonal signals.  相似文献   
99.
S. Furukawa    S. Nakachi    T. Matsubara    K. Yabuta    T. Takeuchi  M. Baba 《Allergy》1990,45(5):375-381
Measurements of IgE levels in the blood of neonates were investigated using filter paper for blood collection in mass screening of congenital metabolic disorders. Time-resolved fluoroimmunometric assay system for the measurement of filter paper blood IgE levels was also studied. In an analysis of the present results, IgE values of at least 0.015U/ml, the measurement limit, were considered as high. High IgE levels in filter paper blood were seen in 28 (7.2%) of the 389 cases. When the relation with serum IgE levels at 18 months of age was investigated in 134 of 389 subjects, high serum IgE levels were also found in about 86.7% of the subjects with high IgE levels in filter paper blood. In addition, when the relation between family history of atopic disease and presence of atopic disease in the first 18 months of age was investigated in 203 of the 389 subjects, about 90% of the subjects with a family history of atopic disease and high IgE levels in filter paper blood developed atopic disease. Since filter paper blood is routinely collected in Japan, IgE levels in this blood should be widely checked for the prediction of onset of atopic disease in infants.  相似文献   
100.
The interaction between polymer and solvent in highly concentrated polymer solutions was studied by inverse gas-liquid chromatography as a function of the molecular weight of polymer. The heat interaction parameter was estimated for the systems polystyrene(PS)-benzene, -toluene, -pyridine, -ethylbenzene, and -anisole. It was found that the heat interaction parameter for the concentrated polystyrene systems PS-toluene, PS-pyridine, and PS-benzene exhibits a similar behavior as in the dilute polystyrene solutions determined by calorimetry at 298,15 K. Further, the heat interaction parameter in both the concentrated and dilute polymer solutions is considerably dependent on the molecular weight of polymer.  相似文献   
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