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91.
BACKGROUND: Long-term results after aortic value replacement for aortic stenosis can be correlated to a cardiac-related pre-operative risk profile. This predictability indicates that there is a common basis in subtle or overt structural abnormalities of left ventricular myocardium. METHODS AND RESULTS: Forty-nine patients aged 24-82 (mean 61) years, with aortic stenosis had a full wall thickness transmural biopsy of the left ventricular antero-lateral free wall during aortic valve replacement. Echocardiography and radionuclide ventriculography were performed prior to, and 18 months (n = 41) after, the operation. Postoperative follow-up to a maximum of 7.7 years was 100% complete. Pre-operatively, all patients had an increase in both the left ventricular mass index (202 +/- 67 g.m-2) and the muscle cell diameter (41 +/- 8 microns); other morphological data included a muscle cell nucleus volume of 752 +/- 192 microns3, a muscle cell mass index of 163 +/- 54.m-2, and a fibrous tissue mass index of 39 +/- 16 g.m-2. Patients with a pre-operative episode of clinical left ventricular failure (n = 19) had significantly greater morphological variables than those without. Pre-operative ejection fraction and other measures of systolic function correlated inversely with the morphological data, except for the fibrous tissue mass index; diastolic function indices correlated inversely with all the morphological variables. At the 18-month re-study, the same general picture was noted, but with an underlying strengthening, especially of the muscle cell mass index. Overall, the mass index dropped to 152 +/- 51 g.m-2 (P < 0.0001), but in 17% of the patients it became normal; the mass index at 18 months was directly correlated to morphological variables. A high muscle cell nucleus volume was identified as an independent predictor of early and late mortality. CONCLUSIONS: Abnormalities of the hypertrophied left ventricular muscle cell and the degree of muscle hypertrophy are, to some degree, underlying determinants of pre-operative symptomatology, pre- and postoperative ventricular function, and early and late mortality after valve replacement for aortic stenosis. Incomplete hypertrophy impaired results, was related to pre-operative myocardial structural abnormalities.  相似文献   
92.
Oligodeoxynucleotides (ODNs) labelled with an appropriate radionuclide could provide a means to identify serious diseases early on and thereby help initiate treatment at a very early phase. Regardless of important issues like in-vivo stability and membrane passage, the key issue for the oligonucleotide approach is the ability of the radiolabelled ODN to hybridize to the target mRNA. The secondary structure of mRNA does not permit all complementary ODNs to hybridize and a careful selection of the probe with consecutive testing is therefore necessary. This study was initiated to demonstrate hybridization of a 99Tcm-labelled 20-mer ODN to RNA of CAPL (S100A4), a gene reported to be overexpressed in metastatic cancers like breast carcinoma and osteosarcoma. The phosphodiester ODN GX-1 (antisense) and two control sequences (scrambled and random) were conjugated to the bifunctional chelating agent S-benzoyl-mercaptoacetyltriglycine (S-benzoyl-MAG3) and labelled with 99Tcm. The radiolabelled ODNs were purified on a C18 mini-column and characterized on a reverse-phase HPLC system. The radio-chemical purity was > 90% and the product was stable for > 6 h in aqueous medium. The hydrization properties of unlabelled, 32P-labelled and 99Tcm-labelled ODNs to transcribed RNA were studied using polyacrylamide gel electrophoresis (PAGE). Direct hybridization of GX-1 to transcribed RNA was demonstrated. A 50-fold excess of unlabelled ODN over transcribed RNA caused a near to complete consumption of RNA by RNase H activation. In 1:1 proportions of radiolabelled (32P and 99Tcm) ODNs to RNA, only radiolabelled GX-1 was found to hybridize to RNA in a PAGE system. The radiolabelled control ODNs did not show signs of hybridization. This study demonstrates that 3'-99Tcm-labelling of ODNs does not interfere with the hybridization properties of the ODNs in solution, making 99Tcm-labelling an attractive procedure for the future development of antisense technology in imaging.  相似文献   
93.
The method of proteinic catabolism degree estimation in potential renal transplant recipients was elaborated. It is based on the urea and creatinine level in blood determination and calculation of the metabolism index according to the formula. The substantiation of the patients treatment tactics and estimation of its efficacy was permitted by determination of predominational metabolism tendency.  相似文献   
94.
In this experimental study brief/prolonged and single/repeated, nociceptive stimuli (laser, thermode and electrical) were used to investigate sensory changes in capsaicin-induced primary and secondary hyperalgesia. The pain threshold to prolonged thermode stimulation was reduced in the primary area and remained constant in the secondary area. The pain thresholds to brief laser and electrical stimuli remained constant in the primary but reduced in the secondary area. The summation pain threshold to repeated (five stimuli delivered at 0.5, 1, 2 and 3 Hz) laser and electrical stimuli was reduced in the secondary area. The stimulus response functions to single laser and electrical stimuli were increased in the secondary area.  相似文献   
95.
96.
The literature concerning the importance of Q10 for health and disease has been reviewed. Dietary intake together with normal in vivo synthesis seems to fulfil the body's demands for Q10 in younger, healthy individuals. The importance of Q10 in general well-being has not been investigated in controlled experiments. The literature allows no firm conclusions about the significance of Q10 in physical activity. In different cardiovascular diseases a positive effect of oral Q10 supplementation has been reported, especially in chronic heart failure. These effects should be further examined. No important adverse side effects have been reported from experiments using daily supplements of up to 200 mg of Q10 for six to twelve months, and 100 mg daily for up to six years.  相似文献   
97.
Capillary electrophoresis was used to separate diastereomers and enantiomers of synthesized thiopyrans and thiinopyrroles. Separation conditions were optimized by varying the buffer parameters, i.e., kind and concentration of chiral selector, pH, main buffering component, micelle forming additives, and content of organic solvents. The interaction of thiopyrans and thiinopyrroles with beta- and gamma-cyclodextrins results in the separation of enantiomers and diastereomers. The magnitude of the resolution depends on the spatial requirements of the different substituents of the analytes and the dimensions of the cyclodextrin cavity. For well-separated enantiomers or diastereomers the identification and characterization of degradation products was possible.  相似文献   
98.
The normal flora is typified by the yeast-like fungi Malassezia (Pityrosporum). Successful attempts at treating patients with atopic and seborreic dermatitis, pityriasis versicolor, and psoriasis with antifungicides confirm the involvement of these fungi in the etiology and development of these diseases. In patients with various skin diseases, an immune response to M. furfur is specific. In those with psoriasis, it is characterized by the higher chemoatractant activity of polymorphonuclear leukocytes stimulated by a M. furfur extract and by the immune response of IgG antibodies with immunoreactive proteins having a molecular weight of 100-120 kD. Patients with atopic dermatitis show a hyperimmune IgE-mediated response to M. furfur, with its specific Th2-lymphocytes inducing the atopic cytokines (IL-4, IL-10) that stimulate allergic reactions to other allergens. Those with pityriasis versicolor had impaired keratinocytic pigment exchange due to azelainic acid produced by M. furfur. The cause of transformation of the yeast phase of M. furfur to the mycelial one is presumably to be changes in the composition of fatty acids of the sebaceous glands due to increased androgen concentrations.  相似文献   
99.
100.
Present paper is aimed at assessing the effect of hypoxic gaseous mixtures intended for the use as the fire suppression agents within closed volumes on the basis of argon with addition of carbonic acid on the body of mammalia. Three experiments were performed on the male white laboratory Wistar rats. It is indicated that argon adding to the hypoxic mixtures containing 4-5% volume increases animal survivability as compared to analogous nitrogen-based mixtures. An addition of 4-8% volume of carbonic acid impairs the of animal condition and reduces the survival rate. There noted a pronounced negative effect of the increased temperature on the survival time in the hypoxic media. One can draw inference about the principal possibility of using argon for formation of the hypoxic gaseous mixtures possessing fire suppression properties.  相似文献   
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