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81.
The mechanism of a rise in blood pressure after kidney irradiation is unclear but most likely of renal origin. We have investigated the role of the renin-angiotensin system and dietary salt restriction in the development of systolic hypertension after bilateral kidney irradiation in young and adult rats. Three to 12 months after a single X-ray dose of 7.5 or 12.5 Gy to both kidneys of young and adult rats, the systolic blood pressure (SBP) and plasma renin concentration (PRC) were measured regularly. A single X-ray dose of 12.5 Gy caused a moderate rise in SBP and a slight reduction in PRC in both young and adult rats. A dose of 7.5 Gy did not significantly alter the SBP or PRC during the follow-up period of 1 year. In a second experiment, the kidneys of young rats received an X-ray dose of 20 Gy. Subsequently, rats were kept on a standard diet (110 mmol sodium/kg) or a sodium-poor diet (10 mmol sodium/kg). On both diets, SBP started to rise rapidly 3 months after kidney irradiation. Sodium balance studies carried out at that time revealed an increased sodium retention in the irradiated rats compared to controls on the same diet. In rats on a low sodium intake, there was neither a delay nor an alleviation in the development of hypertension. Compared to controls, the PRC tended to be lower in irradiated rats up to 4 months after irradiation. Subsequently, malignant hypertension developed in all 20 Gy rats, resulting in pressure natriuresis, stimulating the renin-angiotensin system. Our findings indicated that hypertension after bilateral kidney irradiation was not primarily the result of an activation of the renin-angiotensin system. Although there were some indications that sodium retention played a role, dietary sodium restriction did not influence the development of hypertension. 相似文献
82.
S. S. Weinreich Bogda Hoebe-Hewryk A. R. van der Horst Claire J. P. Boog Pavol Ivanyi 《Immunogenetics》1997,46(1):35-40
Ankylosing enthesopathy (ANKENT) is a spontaneous mouse joint disease with strikingly similar pathology to human HLA-B27-associated
enthesopathies such as ankylosing spondylitis. In C57Bl/10 mice, transgenic HLA-B*2702 as well as H2 genes have been shown to be relative risk factors for ANKENT. To investigate the role of major histocompatibility
complex (MHC) class I expression in disease pathogenesis, ANKENT occurrence was compared among β2-microglobulin (β2m) knockout littermates with or without transgenes for HLA-B*2702 and human β2m. In the knockout phenotype lacking β2m, ANKENT occurrence is significantly reduced (P = 0.016). In the absence of β2m, B*2702 is not detected on the cell membrane, nor does it increase the risk for ANKENT. This means that the previous finding
that HLA-B*2702 increases susceptibility to ANKENT in C57Bl/10 mice cannot be ascribed to a transgene insertion effect. Rather, in order
to increase disease susceptibility, B*2702 must be coexpressed with mouse β2m (mo-β2m). In contrast, when HLA-B*2702 is expressed with β2m of human origin, disease susceptibility is not affected. Thus, both H2b-derived class I heterodimers and HLA-B*2702/mo-β2m heterodimers contribute to ANKENT susceptibility. 相似文献
83.
The beta-lactamase-inhibiting activity of 6m-ethyl-pyrid-2-yl-ammine palladium-dichloride (Pd 25681) and cis-dichloro-diammine-platinum(II) was studied and compared with the enzyme inhibitory action of potassium clavulanate and the penicillanic acid sulfone CP 45899. Using the nitrocefin test method and the Titertek/Microtiter equipment CP 45899 and potassium clavulanate were the strongest inhibitors of the Bacillus cereus beta-lactamase. Cis-dichloro-diammine-platinum(II) was fourfold less active than the palladium complex PD 25681 in ?quimolar concentration. The following ID50 values were found: CP 45899: 0.0281 microgram; K-clavulanate: 0.1274 microgram; Pd 25681: 3.8603 microgram; cis-dichlorodiammine-platinum(II): 12.5120 microgram/100 microliter. 相似文献
84.
Dr. med. W. Höpker 《Cell and tissue research》1953,38(3):218-229
Zusammenfassung Bei supravitaler Fixierung und Anwendung besonderer Färbetechnik lassen sich in zahlreichen Nucleoli der Nervenzelle bei einer Reihe von Säugetieren vielfältige Strukturen erkennen, welche auch mit der Phasenkontrastoptik nachweisbar sind. Es läßt sich nachweisen, daß aus diesen Strukturen, die als Innenkörperchen bezeichnet werden. die Vakuolen entstehen, welche auf Grund des morphologischen Substrates als ein physiologisches Produkt des Nucleolus anzusehen sind. Damit erfahren die Vorstellungen von Körner (1937), C. und O. Vogt 1946, 1947) u. a. eine weitere Stütze.Die Untersuchungen wurden durch die Unterstützung der Deutschen Forschungsgemeinschaft ermöglicht. 相似文献
85.
A total dosage up to 1 mg PGF2a as i.v. infusions of 10–40 μg/min. was investigated on patients with arrhythmias of several kinds. We found therapeutic effects in 5 of 6 patients with constant extrasystoles and in one patient with digitalis - induced partial AV-block respectively. In 3 of 4 patients with acute tachyarrhythmias the results were not convincing, probably due to a dosage not high enough. An increase of the diastolic stimulation threshold usually seen with other antiarrhythmics was not to be observed in 3 patients. The mechanism of action of PGF2a has not yet been clarified. 相似文献
86.
Plant and Soil - Silicon (Si) has been shown to beneficially affect plant performance under stressful environmental conditions, such as water or nutrient deficiency. Here we tested the effects of... 相似文献
87.
Georg Söderbom 《Ethnos》2013,78(1-2):95-100
Current debates over the concept of culture are examined, especially with regard to the relationship of culture to bounded collectivities, human nature, and individuality; present‐day views are seen against the background of back‐and‐forth swings in the history of anthropological thought. Recent theorizing about cultural acquisition is also considered. 相似文献
88.
Orvar Löfgren 《Ethnos》2013,78(3-4):184-213
The paper approaches Dumont's hypothesis of value hierarchy by examining the interconnection between gender, kinship and seniority in Malay rural society, maintaining the idea that seniority is a prominent value. A process is described in which a structure of gender‐neutral seniority and balanced gender collectivities gives way to a stronger collusion between seniority and maleness, personified in the husband‐wife dyad. The author is open to the possibility of a “hierarchising impulse” in cultural processes, but doubts that ultimate values will ever fully emerge in social realities because “society” has no unambiguous delimitation, and because organizational and communicative domains shrink and expand over time so that any dominant value can be challenged through organizational innovations. 相似文献
89.
90.
Aranya Manosroi Narinthorn Khositsuntiwong Friedrich Götz Rolf G. Werner 《Journal of liposome research》2013,23(2):91-98
Transdermal absorption of luciferase plasmid (pLuc) was enhanced by loading in elastic cationic liposomes and niosomes and the application of iontophoresis or the stratum corneum (SC) stripping method. Cationic liposomes (DPPC/Chol/DDAB at a 1:1:1 molar ratio) and niosomes (Tween61/Chol/DDAB at a 1:1:0.5 molar ratio) were prepared by the freeze-dried empty liposomes method. The elastic vesicles were prepared by hydrating the lipid or surfactant film by 25% of ethanol instead of distilled water. Gel electrophoresis of all nanovesicles showed the 100% pLuc entrapment efficiency. All nanovesicles loaded with pLuc showed larger vesicular sizes than the nonloaded vesicles of about 1.4 times for liposomes and 1.7 times for niosomes. The nanovesicles loaded with pLuc demonstrated less positive zeta potential than the nonloaded vesicles. The pLuc loaded in elastic vesicles kept at 4 ± 2 and 27 ± 2°C for 8 weeks gave the remaining pLuc of about 70 and 60% for liposomes and 85 and 73% for niosomes, respectively. For nonelastic vesicles kept at 4 ± 2°C, 56 and 61% of the remaining pLuc were observed for liposomes and niosomes, respectively, while at 27 ± 2°C, all pLuc were degraded. The deformability indices of the elastic liposomes and niosomes loaded with the pLuc were 16.64 ± 2.92 and 20.72 ± 0.82, whereas the nonelastic vesicles gave 9.35 ± 0.09 and 10.08 ± 0.12, respectively. Transdermal absorption through rat skin pretreated with SC stripping or treated with iontophoresis of pLuc loaded in nanovesicles by vertical Franz diffusion cells was investigated at 37°C. The cells were stopped and the skin and the receiving solution were withdrawn at 1, 3, and 6 hours and the pLuc contents in the stripped SC, whole skin (viable epidermis and dermis; VED), and the receiving solution were assayed by the modified gel electrophoresis and gel documentation. Without the SC stripping technique or iontophoresis, the pLuc loaded and nonloaded in nonelastic cationic liposomes or niosomes were not found in SC, VED, and receiving solution. The fluxes in the whole skin of pLuc loaded in nonelastic liposomes and niosomes with SC stripping and iontophoresis at 6 hours gave 2.73 ± 0.46 and 3.83 ± 0.73, and 7.01 ± 1.22 and 9.60 ± 1.31 g/cm2/h, respectively, while pLuc loaded in elastic liposomes and niosomes without the SC stripping and iontophoresis at 6 hours showed 2.79 ± 0.09 and 2.84 ± 0.04 g/cm2/h, respectively. The pLuc loaded in elastic niosomes or in nonelastic niosomes with iontophoresis was found in the receiving solution with a higher amount than that loaded in elastic liposomes or nonelastic liposomes with iontophoresis. The fluxes in the receiving solution of pLuc loaded in nonelastic liposomes and niosomes with iontophoresis at 6 hours were 6.71 ± 0.31 and 8.82 ± 0.28 g/cm2/h, respectively. For elastic liposomes and niosomes, the fluxes of the loaded pLuc in the receiving solution were the same, at about 1.9 g/cm2/h. Although pLuc loaded in nonelastic niosomes with iontophoresis gave the highest delivery of the plasmid in VED and receiving solution, a more promising applicable approach for gene delivery has been suggested to be the elastic niosomal systems, since no equipment is required. 相似文献