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排序方式: 共有768条查询结果,搜索用时 15 毫秒
1.
Mirna SuČIĆ Dubravka Boban Mirjana MarkoviĆ-glamoČak Mladen PetroveČki Matko MaruŠIĆ Boris Labar 《Medical oncology (Northwood, London, England)》1992,9(1):41-45
Cytochemical analysis of leukemic blasts from 46 patients with acute myeloblastic M2 leukemia (according to the FAB classification)
was performed before and after cytostatic therapy, and compared with findings obtained in 20 age- and sex-matched control
subjects. Cytochemical findings for myeloperoxidase (MPO), Sudan black B, acid phosphatase and alpha-naphthyl-acetate esterase
(ANAE) were related to the achievement of the first complete remission (CR),i.e. data were compared after the patients had been divided into CR and non-CR groups. The analysis clearly showed that a high
proportion of myeloperoxidase- and, to a lesser extent, Sudan black B-positive blasts before treatment may have constituted
a significantly unfavourable prognostic factor. 相似文献
2.
F. ČULO I. Klapan V. Katic T. Kolak B. Bakula 《Medical oncology (Northwood, London, England)》1992,9(1):35-39
The production of prostaglandin Eex vivo was studied in samples of 31 squamous cell carcinomas of the head and neck (SCCHN) and 12 adenocarcinomas of gastrointestinal tract (ACGI). As a control, the PGE production was measured in 22 samples of noninvolved mucosa in patients with SCCHN and 12 samples of gastrointestinal mucosas. The mean PGE production by SCCHN was significantly higher than in normal mucosa. Furthermore, the PGE production by tumors which recurred or spread to regional lymph node within 18 months after surgery was higher than in tumors which did not recur within that interval. Also, production of PGE by noninvolved mucosa was significantly higher in patients in which tumor recurred after surgery than in patients which were tumor free. On the other hand, the mean production of PGE by ACGI was not different from that of normal mucosa. These data show that determination of PGE production might have prognostic significance in SCCHN. 相似文献
3.
The effect of single and repeated UVB radiation on rabbit cornea 总被引:1,自引:0,他引:1
Miroslav Fris May-Britt Tessem Jitka Čejková Anna Midelfart 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(12):1680-1687
Background Cumulative effect of ultraviolet radiation (UVR) is an important aspect of UV corneal damage. The purpose of this study was to apply high resolution magic angle spinning proton nuclear magnetic resonance (HR-MAS 1H NMR) spectroscopy to evaluate the effect of single and repeated UV radiation exposure of the same overall dose on the rabbit cornea.Methods Corneal surfaces of 24 normal rabbit eyes were examined for the effects of UVB exposure (312 nm). In the first group (UVB1), animals were irradiated with a single dose (3.12 J/cm2; 21 min) of UVB radiation. The animals in the second group (UVB2) were irradiated three times for 7 min every other day (dose of 1.04 J/cm2; days 1, 3, 5) to give the same overall dose (3.12 J/cm2). The third group served as an untreated control group. One day after the last irradiation, the animals were sacrificed, and the corneas were removed and frozen. HR-MAS 1H NMR spectra from intact corneas were obtained. Special grouping patterns among the tissue samples and the relative percentage changes in particular metabolite concentrations were evaluated using modern statistical methods (multivariate analysis, one-way ANOVA).Results The metabolic profile of both groups of UVB-irradiated samples was significantly different from the control corneas. Substantial decreases in taurine, hypo-taurine and choline-derivatives concentrations and substantial elevation in glucose and betaine levels were observed following the UVR exposure. There was no significant difference between the effect of a single and repeated UVB irradiation of the same overall dose.Conclusions For the first time, the effects of single and repeated UVR doses on the metabolic profile of the rabbit cornea were analysed and compared. The combination of HR-MAS 1H NMR spectroscopy and modern statistical methods (multivariate analysis, one-way ANOVA) proved suitable to assess the overall view of the metabolic alterations in the rabbit corneal tissue following UVB radiation exposure. 相似文献
4.
Marija Čarman-Kržan 《Inflammation research》1983,13(2-3):162-166
The antagonist-sensitive binding of [3H]mepyramine to beef aortic membranes was as expected for binding to histamine H1-receptors. [3H]mepyramine binds rapidly and in saturable fashion to the specific receptor sites, specific binding reaching equilibrium in 3 min at 37°CScatchard's analysis of the binding data gave a dissociation constant of 3.0 nM for the radioligand-receptor complex and maximal number of binding sites: 31 fmol/mg protein. In the competition studies histamine H1-antagonists are more potent inhibitors of radioligand binding than H2-antagonist. They inhibit [3H]mepyramine binding in the following order: mepyramine >triprolidine 相似文献
5.
Development of flow cytogenetics and physical genome mapping in chickpea (Cicer arietinum L.) 总被引:2,自引:0,他引:2
K. Vláčilová D. Ohri J. Vrána J. Číhalíková M. Kubaláková G. Kahl J. Doležel 《Chromosome research》2002,10(8):695-706
Procedures for flow cytometric analysis and sorting of mitotic chromosomes (flow cytogenetics) have been developed for chickpea (Cicer arietinum). Suspensions of intact chromosomes were prepared from root tips treated to achieve a high degree of metaphase synchrony. The optimal protocol consisted of a treatment of roots with 2mmol/L hydroxyurea for 18h, a 4.5-h recovery in hydroxyurea-free medium, 2h incubation with 10µmol/L oryzalin, and ice-water treatment overnight. This procedure resulted in an average metaphase index of 47%. Synchronized root tips were fixed in 2% formaldehyde for 20min, and chromosome suspensions prepared by mechanical homogenization of fixed root tips. More than 4×105 morphologically intact chromosomes could be isolated from 15 root tips. Flow cytometric analysis of DAPI-stained chromosomes resulted in histograms of relative fluorescence intensity (flow karyotypes) containing eight peaks, representing individual chromosomes and/or groups of chromosomes with a similar relative DNA content. Five peaks could be assigned to individual chromosomes (A, B, C, G, H). The purity of sorted chromosome fractions was high, and chromosomes B and H could be sorted with 100% purity. PCR on flow-sorted chromosome fractions with primers for sequence-tagged microsatellite site (STMS) markers permitted assignment of the genetic linkage group LG8 to the smallest chickpea chromosome H. This study extends the number of legume species for which flow cytogenetics is available, and demonstrates the potential of flow cytogenetics for genome mapping in chickpea. 相似文献
6.
Marija Čarman-Kržan 《Inflammation research》1986,18(1-2):120-123
Agonist interaction with histamine H1-receptor in [3H] mepyramine bovine aortic membranes labeled with [3H] mepyramine is selectively regulated by cations and guanine nucleotides. GTP and his nonhydrolisable analog Gpp(NH)p' markedly decrease histamine affinity for [3H] mepyramine binding sites. The effect of GTP is reversed in the presence of divalent cation, magnesium. Calcium and sodium ions have little effect on histamine binding whereas magnesium ions decrease the affinity of histamine for the radioantagonist binding sites about tenfold.GTP has little effect on [3H] mepyramine binding and the interaction of H1-antagonist triprolidine with histamine H1-receptors. The above results indicate that the effect of guanine nucleotides, mono and divalent cations involves the effect on membrane signal transducing mechanism probably GTP-binding protein(s) cation regulatory site(s) rather than receptor binding site directly. 相似文献
7.
Dr. M. Elleder F. Šmíd K. Harzer J. Čihula 《Virchows Archiv : an international journal of pathology》1980,385(2):215-231
Summary The results of a complex analysis of liver tissue are presented (four biopsy and two autopsy samples) obtained from six patients with Niemann-Pick disease (NPD) with a gross deficiency of sphingomyelinase (SMase) accompanied by a typical increase in sphingomyelin (SM). There were five cases of NPD type A (four of them with an atypical, prolonged course) and one case of type B. By means of lipid histochemistry it was possible to demonstrate SM storage both in hepatocytes and in the reticuloendothelial system (RES) of the liver (Kupffer cells and portal macrophages) and to show in two siblings with NPD type A a so-far undescribed centrilobular storage pattern. Enzyme histochemistry revealed a secondary deficit of nonspecific esterase activity and acid -galactosidase in liver storage macrophages and varying degrees of suppression of hepatocytic enzyme activities as a reaction to lipid storage of sudden onset. Ultrastructurally, it was possible to demonstrate cholesterol in lysosomes by using digitonin fixation, the involvement of Ito cells in lipid storage, the aggregation of storage lysosomes with certain other organelles and their occasional connections with the endoplasmic reticulum. The problems of possible lipid extraction during processing were considered as a cause of pronounced lysosomal electron-lucidity and of the ultrastructural identification of the participating lipopigment. The significance of the findings is discussed in relation to the existing classification and, particularly, to the stored lipid dilemma of cases of NPD type C. 相似文献
8.
Vesna Čapkun Davor Eterović 《European journal of nuclear medicine and molecular imaging》1985,11(4):120-122
Radionuclide-angiography (RNA_ left-to-right intracardiac-shunt quantification algorithms, based on the part-by-part fit technique and the use of a so-called gamma variate model function (GVF), were tested via simulation analysis using data obtained from normal subjects. A good bolus of radioindicator was obtained by administering it directly into the vena subclavia. Normal subjects were defined as those having pulmonary histograms (PH) with no visible distortion caused by a shunt. Pure, non-superimposed data on the downslope of the PH curves, which are lost in presence of a shunt, proved to be appropriate reference values for testing the accuracy of results of standard shunt quantification algorithms. A generalized four-parameter GVF was introduced in order to extend the flexibility of the model function. The use of the three-parametric GVF to reconstruct the downslope of the PH curve out of the upslope data proved to be inadequate. This reveals an evident source of error in algorithms that calculate the shunt contribution by fitting GVF parameters to so-called difference-curve data. It is concluded that the inherent restricted statistical weight of RNA data prevents accurate results being obtained from standard RNA-shunt-assessment algorithms. 相似文献
9.
Jarmila Kruseová Jelena Černíková Marina Zámečníková Lucie Hřivnová Stanislava Koloušková Michaela Čepelová Edita Kabíčková Václav Čapek Aleš Lukš Tomáš Eckschlager 《Andrologia》2021,53(1):e13853
The objective of this study was to compare semen quality (sperm density, progressive motility and spermia) between long-term childhood cancer survivors and a control group of males. The second objective was to correlate the semen analysis of the survivors with cancer treatment and endocrine status. The semen quality of 143 survivors (median age, 23.6 years) was compared to 200 men (median age, 27.9 years) who had not been diagnosed with cancer. The cancer-related risk factors and gonadotrophin levels were compared. Overall, 65% of the survivors had abnormal semen analysis compared to 26.5% of the controls (p < 0.0001). Survivors with nonaspermia had lower sperm density than the controls (p < 0.001). Other observed correlations were not significant. Survivors who were treated with alkylating agents were more likely to have abnormal semen analysis (p < 0.008). Follicle-stimulating hormone and luteinising hormone levels were significantly elevated (p < 0.0001) in survivors with abnormal semen analysis. The semen quality parameters, except for low sperm density, did not differ in survivors with nonaspermia compared to the controls. The risk factors included treatment with alkylating agents. Elevated gonadotrophin levels correlated with abnormal semen analysis. All cancer survivors should be made aware of the possibility of suffering from cancer treatment-related infertility. 相似文献
10.
Summary Paralytic dislocation of the hip in cerebral palsy may be prevented by soft tissue surgery and the results of two procedures are reported. Twenty hips were treated by adductor tenotomy alone and this was unsuccessful in every case. An alternative method was carried out in 42 hips in 25 patients. The procedure combined adductor tenotomy with release of the hip muscles including iliac crest resection, tenotomy of the rectus femoris, recession of the iliopsoas and, when necessary, either release or transposition of the knee flexors. This was much more successful in decreasing migration of the femoral head.
Résumé Dans la paralysie cérébrale la luxation de la hanche peut être efficacement évitée grâce à des interventions chirurgicales portant sur les parties molles. Nous avons étudié les résultats de deux types d'opération: la ténotomie des adducteurs et cette même opération associée à la désinsertion de la hanche (avec transposition du psoas sur la partie proximale de la capsule) et éventuellement avec allongement des fléchisseurs du genou ou transposition de ceux-ci sur la partie distale du fémur. Soixante-deux hanches ont été opérées chez 45 malades. Les résultats de la ténotomie isolée des adducteurs ont été insuffisants dans les 20 cas opérés (âge moyen au moment de l'opération, 4, 5, ans, recul 6,5 ans). Les résultats du deuxième type d'intervention ont été meilleurs dans les 42 hanches opérées, le pourcentage migratoire de la tête fémorale a été réduit de 45% (âge moyen lors de l'opération 7 ans, recul 5 ans). Plus de la moitié des malades étaient capables de se déplacer.相似文献