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排序方式: 共有10000条查询结果,搜索用时 171 毫秒
991.
V T Ivashkin Iu V Grigor'ev A I Sinopal'nikov N V Korneev D N Levitski? E A KazakovaIGVirs 《Kardiologiia》1991,31(8):59-61
The clinical effects of Tenoric, a long-acting combined drug (atenolol and chlorthalidone in a tablet), were studied in 31 patients with Stages I and II hypertensive disease, by using echocardiography, daily automatic blood pressure monitoring, bicycle ergometry, measurements of plasma renin and aldosterone. The drug was found to be highly clinically effective in labile and sustained hypertension. When given once or twice a day, it makes it possible to reliably monitor blood pressure, improve hemodynamic parameters, as reflected by lower cardiac output and decreased peripheral vascular resistance, reduce the estimated mass of the left myocardium, alleviate a pressor response to exercise and enhance its tolerance, lower plasma renin levels. The side effects of the drug are minimal and include moderate bradycardia. Peripheral vasospasm and systemic weakness were observed in single cases. There were no atherogenic changes in lipid spectrum and disturbed glucose and uric acid metabolism during the drug therapy. 相似文献
992.
L R Kelland P Mistry G Abel F Freidlos S Y Loh J J Roberts K R Harrap 《Cancer research》1992,52(7):1710-1716
Clinically, human testicular nonseminomatous germ cell tumors exhibit remarkable sensitivity to platinum-based chemotherapy. To define better the mechanistic basis for this unusual sensitivity, the biochemical determinants of platinum-induced cytotoxicity have been investigated in a human testicular tumor cell line (GCT27) established from a previously untreated patient and in an in vitro derived 5.6-fold cisplatin-resistant stable variant (GCT27cisR). Compared to 12 ovarian and 5 cervical human tumor cell lines, the parent GCT27 line was among the most sensitive to the cytotoxic effects of both cisplatin (dosage producing 50% inhibition, 0.2 microM) and carboplatin (dosage producing 50% inhibition, 2.9 microM), thus reflecting clinical data. A 4-day exposure sulforhodamine B-staining assay was used to determine that GCT27cisR was cross-resistant to carboplatin and iproplatin and the classical bifunctional alkylating agents melphalan and chlorambucil. Partial cross-resistance was observed to tetraplatin, methotrexate, and mitomycin C. No cross-resistance was observed to Adriamycin, etoposide, vinblastine, bleomycin, 1-beta-D-arabinofuranosylcytosine, and 5-fluorouracil. Intracellular cisplatin accumulation across the dose range 2.5-100 microM (for 2 h) was 1.6 +/- 0.39-fold (mean +/- SD) greater for the parent line. There was no significant difference in glutathione levels between the two lines. The acquired resistance line was 1.9-fold more resistant than the parent line to the cytotoxic effects of cadmium chloride. There was no significant difference between the two lines, however, in the total amounts of platinum bound to DNA after cisplatin exposure (25, 50, or 100 microM for 2 h). The removal of total platinum adducts from DNA was significantly faster for GCT27cisR compared to the parent line (half-times of removal, 32 and 67 h, respectively). These data suggest that the abnormal sensitivity of the parent testicular tumor cell line to platinum-containing anticancer drugs may be due predominantly to an inherent defect in the ability of these cells to remove platinum from their DNA. This defect is apparently lost in the acquired resistance counterpart. Reduced intracellular accumulation and increased cytoplasmic concentrations of metallothionein may also contribute, in part, to the acquisition of cisplatin resistance in this model. 相似文献
993.
Promutagenic methylation damage in bladder DNA from patients with bladder cancer associated with schistosomiasis and from normal individuals. 总被引:3,自引:0,他引:3
A F Badawi M H Mostafa T Aboul-Azm N Y Haboubi P J O'Connor D P Cooper 《Carcinogenesis》1992,13(5):877-881
Radioimmunoassays (RIAs) have been used to detect the promutagenic lesion O6-methyldeoxyguanosine (O6-MedG) in DNA isolated from the bladder tissues of Egyptian patients presenting with bladder carcinoma and concomitant schistosomiasis (bilharziasis), a parasitic disease known to be associated with the presence of N-nitrosamines in the urine. Alkylation damage was present in the DNA of the majority of the samples (44/46, 96%); 38 samples were of tumour tissue and 8 from uninvolved bladder mucosa. Levels of O6-MedG ranged from undetectable (ND; i.e. less than 0.01 mumol O6-MedG/mol dG) to 0.485 mumol/mol dG with an overall mean of 0.134 +/- 0.10 mumol/mol dG, including the two samples that were below the limit of detection. In contrast, methylation damage was detected in only 4/12 (33%) of the DNA samples from normal bladder tissue of European origin. In these samples levels of O6-MedG ranged from ND to 0.225 mumol/mol dG with an overall mean of 0.046 +/- 0.082 mumol O6-MedG/mol dG. These results confirm that alkylation events can be detected in the DNA of schistosome-infected human bladder tissue. The methylation of uninvolved and tumour tissue DNA to similar extents suggests that the alkylating intermediate may have been present in the urine. These results indicate the need for further investigation to determine whether relationships exist between levels of DNA damage and the prevalence of schistosome infection and/or the extent and type of bacterial infection that frequently accompanies this disease. 相似文献
994.
M Higashigawa Y Komada N Washio H Kuwabara H Hori M Ido M Sakurai 《Leukemia research》1992,16(10):1049-1054
In vitro preincubation with recombinant granulocyte colony-stimulating factor(rhG-CSF, 100 ng/ml) enhanced the cytotoxicity of 1-beta-D-arabinofuranosylcytosine(Ara-C) in leukemic cells resistant to Ara-C from a patient with biphenotypic leukemia. Treatment of the cells with rhG-CSF resulted in a 17-fold increase in DNA synthesis, 4.6-fold increase in percentage of S-phase, and a two-fold increase in Ara-CTP formation. Maximal effect was observed at 72 h of incubation. Combination chemotherapy with rhG-CSF and Ara-C to the patient showed remarkable cytoreduction. These results indicate that recruitment of resistant leukemic cells in cell kinetic quiescence is inducible by rhG-CSF and that it is possible enhancement of the cytotoxicity to cell cycle-specific drugs such as Ara-C. 相似文献
995.
EFNS Guidelines on diagnosis and treatment of brain metastases: report of an EFNS Task Force 总被引:2,自引:0,他引:2
R. Soffietti P. Cornu J. Y. Delattre R. Grant F. Graus W. Grisold J. Heimans J. Hildebrand P. Hoskin M. Kalljo P. Krauseneck C. Marosi T. Siegal C. Vecht 《European journal of neurology》2006,13(7):674-681
The objectives have been to establish evidence-based guidelines and identify controversies regarding the management of patients with brain metastases. The collection of scientific data was obtained by consulting the Cochrane Library, bibliographic databases, overview papers and previous guidelines from scientific societies and organizations. A tissue diagnosis is necessary when the primary tumor is unknown or the aspect on computed tomography/magnetic resonance imaging is atypical. Dexamethasone is the corticosteroid of choice for cerebral edema. Anticonvulsants should not be prescribed prophylactically. Surgery should be considered in patients with up to three brain metastases, being effective in prolonging survival when the systemic disease is absent/controlled and the performance status is high. Stereotactic radiosurgery should be considered in patients with metastases of 3–3.5 cm of maximum diameter. Whole-brain radiotherapy (WBRT) after surgery or radiosurgery is debated: in case of absent/controlled systemic cancer and Karnofsky Performance score of 70 or more, one can either withhold initial WBRT or deliver early WBRT with conventional fractionation to avoid late neurotoxicity. WBRT alone is the treatment of choice for patients with single or multiple brain metastases not amenable to surgery or radiosurgery. Chemotherapy may be the initial treatment for patients with brain metastases from chemosensitive tumors. 相似文献
996.
The current study investigates the effect of megestrol acetate, a synthetic progestin, on the activity of interleukin-1. Murine thymocytes were suspended in vitro and stimulated with varying concentrations of interleukin-1. [3H]Thymidine uptake was observed as an index of thymocyte proliferation. A dose-dependent increase in [3H]thymidine uptake was observed with increasing concentrations of interleukin-1. When megestrol acetate was added to the solution, a marked suppressive effect was observed. Higher doses of megestrol acetate had a greater suppressive effect on thymocyte proliferation. Additional investigation is required to further delineate the potential systemic effects of megestrol acetate. 相似文献
997.
利用主客体分子包结现象选择分离蛇床子有效成分的方法 总被引:2,自引:0,他引:2
利用1,1,6-四苯基-2,4-已二炔-1,6-二醇(I)的包结能力,可简单而迅速地从蛇床子中选择分离出有效成分欧前胡素(2)和花椒毒素(3),收率分别为0.054%(2)和0.002%(3)。本文用UV,IR,1HNMR和13CNMR验证了2和3的化学结构,并用HPLC检验了2和3的纯度。X-射线衍射晶体结构分析表明主体分子I与组分2靠氢键形成包结物,它们的摩尔比为1:2,氢键长为2.8612A。包结物晶体属单斜晶系,空间群为已P21/C,晶胞参数:a=15.468(5)A,b=8.595(3)A,c=18.663(7)A,β=93.64(5)°,Z=4和R=0.088。 相似文献
998.
Natural history of extensive Mongolian spots in mucopolysaccharidosis type II (Hunter syndrome): a survey among 52 Japanese patients 总被引:1,自引:0,他引:1
T Ochiai† Y Suzuki‡ T Kato‡ H Shichino§ M Chin§ H Mugishima§ T Orii¶ 《Journal of the European Academy of Dermatology and Venereology》2007,21(8):1082-1085
BACKGROUND: Recent reports have shown a correlation between extensive Mongolian spots and mucopolysaccharidosis type II (Hunter syndrome). However, a statistical survey of the incidence and natural history of extensive Mongolian spots among the patients with Hunter syndrome is lacking. OBJECTIVES: To determine the prevalence of extensive Mongolian spots, to determine the natural course of the spots according to age in Japanese patients with Hunter syndrome, and to compare them with the results obtained from the patients' brothers who did not have Hunter syndrome. PATIENTS/METHODS: Fifty-two males with Hunter syndrome aged 3 to 40 years were studied. Twenty-five patients were examined in two clinics to determine the existence and characteristics of the spots. We interviewed their families about the spots in their neonates and the natural course of the spots according to their ages. The same survey was done among another 27 patients using a mailed questionnaire to their families. As control, we investigated 21 brothers of the patients by a mailed questionnaire to their families. RESULTS: The extensive Mongolian spots are identified in almost all the infants with Hunter syndrome and disappear extremely later in their life. The lesions had a high incidence of deep-blue hyperpigmentation. Regardless of age, the overall incidence was 78%. All of the brothers who did not have Hunter syndrome had common-type Mongolian spots in neonates, which regressed during their childhood. CONCLUSION: Our results confirm a strong correlation between extensive Mongolian spots and Hunter syndrome for the Japanese population. The presence of extensive Mongolian blue spots should alert the physician to the possibility of Hunter syndrome. 相似文献
999.
1000.
Autonomic Regulation of Voltage-Gated Cardiac Ion Channels 总被引:3,自引:0,他引:3
ERWIN F. SHIBATA Ph.D. TRACY L.Y. BROWN M.D. Ph.D. ZACHARY W. WASHBURN B.S. JING BAI M.S. THOMAS J. REVAK B.S. CAROL A. BUTTERS M.A. 《Journal of cardiovascular electrophysiology》2006,17(S1):S34-S42
Altering voltage-gated ion channel currents, by changing channel number or voltage-dependent kinetics, regulates the propagation of action potentials along the plasma membrane of individual cells and from one cell to its neighbors. Functional increases in the number of cardiac sodium channels (NaV 1.5) at the myocardial sarcolemma are accomplished by the regulation of caveolae by β adrenergically stimulated G-proteins. We demonstrate that NaV 1.5, CaV 1.2a, and KV 1.5 channels specifically localize to isolated caveolar membranes, and to punctate regions of the sarcolemma labeled with caveolin-3. In addition, we show that NaV 1.5, CaV 1.2a, and KV 1.5 channel antibodies label the same subpopulation of isolated caveolae. Plasma membrane sheet assays demonstrate that NaV 1.5, CaV 1.2a, and KV 1.5 cluster with caveolin-3. This may have interesting implications for the way in which adrenergic pathways alter the cardiac action potential morphology and the velocity of the excitatory wave. 相似文献