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101.
Authors had retrospectively analyzed basic exponents of perinatal care of 256 pregnant diabetic woman in years 1993-1998 hospitalized and delivered in Clinic of Obstetrics and Gynaecology in the town of Bytom. Our results were very similar to the other of Referent Centres Of Technical Methods Bank Used in Diagnostic and Therapy of Diabetes: cesarean sections percentage 51.56%, 4.7% of undelivered pregnancies, 2.34% of new-born delivered with multiple congenital defaults, 17.2% of macrosomies and 39.8% pre-term deliveries were noted. Disadvantage perinatal effects in diabetic women might be reduced by very early diagnosis of diabetic and intensive biophysical and biochemical fetal care, which is strongly suggests by the authors.  相似文献   
102.
DNA alkylating agents such as 1, 2-dimethylhydrazine (SDMH)and azoxymethane (AOM) are potent carcinogens and are widelyused to induce colon tumors in experimental animals. However,standard bacterial mutagenesis assays have failed to detectthe mutagenic effects of these chemicals. Using derivativesof a set of Escherichia coli test strains developed by Cupplesand Miller (Proc. NatL Acad. Set USA, 86, 5345, 1989), we havedemonstrated that under two conditions, SDMH and AOM inducedpoint mutations by several-fold in a dose-dependent manner:(i) of six possible base substitutions, they only induced GC  相似文献   
103.
Whilst the ability of isoantibodies to agglutinate mouse red cells in saline medium does depend in part upon the properties of the antibody molecules, the concentration of antigen upon the red cell and certain genetically determined properties of the cell surface are of even greater importance. The red cells of mice of any strain will give positive results in the human serum:dextran system whilst reactions in a saline medium are unusual. In this paper the term `incomplete antibody' is used to denote antibodies that can only be detected in conjunction with other antibodies in the human serum:dextran system.

The time of appearance of antibodies to homografts of an ascites sarcoma, an ascites leukosis and a solid mammary carcinoma has been studied. Incomplete antibody as defined above has been detected by two methods. In the blocking test incomplete antibody is allowed to react with red cells before contact with complete antibody, a positive result being observed as a fall in titre when the treated red cells are subsequently exposed to complete antibody. In the second type of test, the synergic test, incomplete antibody is mixed with suitably diluted complete antibody and titrated against suitable red cells, a positive result being a significant rise in titre as compared with complete antibody mixed with normal serum. Antibodies produced by the antigen donors did not give significant blocking or synergic effects.

Incomplete antibodies are sometimes detectible on the third day and with regularity on the fourth day. Antibodies `complete' for A strain red cells may appear at any time from the fifth day onwards. There is sometimes a drop in titre of varying duration on the sixth day. This corresponds with the commencement of marked inflammatory changes on the graft bed. The maximum titre is attained at about two weeks. Antibodies may disappear in under three months or persist as long as a year.

The function of antibodies in homograft reactions varies with the target tissue. However, they appear before the onset of anatomical signs of homograft response regardless of the type of target cell.

  相似文献   
104.
Upregulation of hypoxia-inducible factors HIF-1 and HIF-2 is frequent in human cancers and may result from tissue hypoxia or genetic mechanisms, in particular the inactivation of the von Hippel-Lindau (VHL) tumour suppressor gene (TSG). Tumours with VHL inactivation are highly vascular, but it is unclear to what extent HIF-dependent and HIF-independent mechanisms account for pVHL tumour suppressor activity. As the identification of novel pVHL targets might provide insights into pVHL tumour suppressor activity, we performed gene expression microarray analysis in VHL-wild-type and VHL-null renal cell carcinoma (RCC) cell lines. We identified 30 differentially regulated pVHL targets (26 of which were 'novel') and the results of microarray analysis were confirmed in all 11 novel targets further analysed by real-time RT-PCR or Western blotting. Furthermore, nine of 11 targets were dysregulated in the majority of a series of primary clear cell RCC with VHL inactivation. Three of the nine targets had been identified previously as candidate TSGs (DOC-2/DAB2, CDKN1C and SPARC) and all were upregulated by wild-type pVHL. The significance for pVHL function of two further genes upregulated by wild-type pVHL was initially unclear, but re-expression of GNG4 (G protein gamma-4 subunit/guanine nucleotide-binding protein-4) and MLC2 (myosin light chain) in a RCC cell line suppressed tumour cell growth. pVHL regulation of CDKN1C, SPARC and GNG4 was not mimicked by hypoxia, whereas for six of 11 novel targets analysed (including DOC-2/DAB2 and MLC2) the effects of pVHL inactivation and hypoxia were similar. For GPR56 there was evidence of a tissue-specific hypoxia response. Such a phenomenon might, in part, explain organ-specific tumorigenesis in VHL disease. These provide insights into mechanisms of pVHL tumour suppressor function and identify novel hypoxia-responsive targets that might be implicated in tumorigenesis in both VHL disease and in other cancers with HIF upregulation.  相似文献   
105.
Cyanobacterial blooms in drinking water reservoirs may cause a variety of water quality problems, including those of taste and odor, and can compromise the water supply destined for human consumption. In response to this problem an online monitoring tool for analyzing the cyanobacterial concentration in intake water is of practical value. This study demonstrated a positive correlation between phycocyanin fluorescence and cyanobacterial biomass during Microcystis aeruginosa blooms in a lowland drinking water reservoir, using online detection. The highest correlation coefficients were found for a cyanobacterial biomass concentration below 15 mg freshweight/L, indicating that this method can be an effective early warning system. Rapid changes in fluorescence were observed when wind drift moved higher cyanobacterial concentrations into the water intake, indicating that fluorescence could be employed as a quick warning for changed requirements for plant operations.  相似文献   
106.
S-(+)-Norfenfluramine (SNF)-an active metabolite of the now-banned anorexigen fenfluramine-has been implicated in the drug's appetite-suppressing actions and its life-threatening cardiovascular side effects. SNF reduces appetite through serotonin 5-HT(2C) receptor activation; it causes cardiopulmonary side effects through 5-HT(2B) receptor activation. Thus, we attempted to identify molecular determinants of SNF binding to 5-HT(2B) receptors distinct from those underlying SNF-5-HT(2C/2A) receptor interactions. Mutagenesis implicated Val2.53 in SNF binding to 5-HT(2B) receptors. Ligand docking simulations suggested both Val2.53 gamma-methyl groups form stabilizing van der Waals' (vdW) interactions with the alpha-methyl group of SNF. A V2.53L mutation induced a 17-fold decrease in affinity; molecular dynamics (MD) simulations suggested that this decrease resulted from the loss of one 2.53-alpha-methyl group vdW interaction. Supporting this, 1) the binding of norfenfluramine (NF) analogs lacking an S-(+) alpha-methyl group (RNF and alpha-desmethyl-NF) was less sensitive to the V2.53L mutation, and 2) a V2.53A mutation decreased SNF affinity 190-fold, but decreased RNF and alpha-desmethyl-NF affinities only 16- and 45-fold, respectively. We next addressed whether the alpha-methyl group of SNF contributes to 5-HT(2C/2A) receptor affinity. Removal of the alpha-methyl group (RNF and alpha-desmethyl-NF), which reduced 5-HT(2B) receptor binding 3-fold, did not affect 5-HT(2C/2A) receptor binding. An alpha-ethyl substituent (alpha-ethyl-NF), which decreased 5-HT(2B) receptor affinity 46-fold, reduced 5-HT(2C) and 5-HT(2A) receptor binding by 14- and 5-fold, respectively. Finally, we determined that residue 2.53 affects SNF potency and efficacy at 5-HT(2B) receptors but not at 5-HT(2C) and 5-HT(2A) receptors. In conclusion, vdW interactions between residue 2.53 and the alpha-methyl group of SNF contribute to the ligand's 5-HT(2) receptor subtype-selective pharmacology.  相似文献   
107.
Because atherosclerosis has been proven to be an inflammatory disease, it became obvious that the proper treatment of dyslipidemic patients should not only correct lipid parameters but also inhibit the inflammatory state. One of the crucial proinflammatory and procoagulant cytokines participating in the pathogenesis of atherosclerosis is interleukin-1beta (IL-1beta). Therefore, the aim of the study was to asses the effect of statin and fibrate therapy (for dyslipidemia IIa and IIb, respectively) on IL-1beta gene expression and monocyte release evaluated in each patient. Additionally, the effect of hypolipidemic therapy on fibrinolysis was evaluated. The study was carried out in 37 patients: 12 with biochemically confirmed type IIa dyslipidemia (treated with atorvastatin), 12 with type IIb dyslipidemia (treated with fenofibrate), and 13 age- and sex-matched normolipidemic persons (control). IL-1beta concentrations in cultured monocytes and PAI-1 (Plasminogen Activator Inhibitor) plasma levels were measured using the ELISA method. To evaluate the expression of IL-1beta gene in monocytes, a semiquantitive RT-PCR procedure was performed. The results were normalized with the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a housekeeping gene. Although IL-1beta monocyte release was markedly elevated in patients with atherogenic dyslipidemias, IL-1beta gene expression was only slightly and nonsignificantly higher in the studied groups versus control. We have observed significant reduction of IL-1beta mRNA expression after 30-day treatment with the examined drugs (atorvastatin, 2.10 +/- 0.50 versus 1.05 +/- 0.15; P < 0.001, fenofibrate; 2.27 +/- 0.48 versus 1.23 +/- 0.27; P < 0.01). There was no significant difference between statin and fibrate effect on IL-1beta mRNA expression. Similarly, we have noticed significant reduction of IL-1beta release by cultured monocytes after 30-day statin therapy (133.0 +/- 5.7 pg/mL versus 77.0 +/- 3.6 pg/mL; P < 0.01) and fibrate therapy (143.9 +/- 6.5 pg/mL versus 86.2 +/- 5.9 pg/mL; P < 0.01). Besides this antiinflammatory effect, we have observed a 30% reduction of PAI-1 plasma levels in both treated groups. In conclusion, effective 1-month hypolipidemic therapy with atorvastatin or fenofibrate diminished plasma levels of proinflammatory and procoagulatory state markers.  相似文献   
108.
A low level of physical activity and decreased exercise capacity are independent risk factors for cardiovascular and all-cause mortality. The assessment of the level of physical activity and its improvement following preventive procedures is methodologically difficult. In population studies, subjective methods, such as questionnaires, activity records and other somewhat imperfect measures (accelerometers, pedometers, and pulse monitors), are used. Direct and especially indirect assessment of physical capacity with exercise tests has become increasingly more accessible and cheap. Both methods have been proved to have high prognostic value. Assessment of physical capacity enables objectification of information on the level and effects of a subjects physical activity acquired via a questionnaire. Taking into account the above-mentioned issues, the role of the assessment of exercise capacity and its improvement is not adequately appreciated. Routine evaluation of exercise capacity has not been included in the current statements on epidemiology and prevention, even in those with an increased Framingham or SCORE risk index in whom low exercise tolerance has been proved to have an unfavorable influence on prognosis. The importance of an increase in the level of physical activity resulting in an improvement in exercise capacity in different population groups should be verified in the near future, but in our opinion there is indirect but strong evidence that actions to improve exercise capacity should become the main goals in the prevention of cardiovascular and all-cause mortality, such as cessation of cigarette smoking, body weight reduction, correction of lipid and carbohydrate metabolism disturbances, and a decrease in blood pressure.  相似文献   
109.
110.
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