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31.
The femur length/abdominal circumference ratio, expressed as FL/AC X 100, was determined in 156 fetuses and evaluated as a predictor of fetal macrosomia within one week prior to delivery. The normal range (mean +/- 2 SD) in the 105 normal-weight fetuses was 22.0 +/- 2, while the normal range in the 51 macrosomic fetuses was 20.5 +/- 2; these differences were highly significant (P = less than .0001). The predictive power of a positive ratio was 68%, with a sensitivity of 63%. This ratio was particularly useful in the subset (n = 9) of macrosomic fetuses whose mothers were diabetic, correctly identifying 89% of this group. Because it is age independent, this ratio should prove most helpful in identifying fetuses at risk for macrosomia in patients whose dates are not known, since it may become abnormal before the fetal weight falls above the 90th percentile at term (3,900 g). In patients whose dates are known, early fetal macrosomia is best predicted by evaluating the abdominal circumference against normal standards for age.  相似文献   
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The cystic fibrosis membrane conductance regulator can be activated through beta2-adrenoceptor (beta2AR) stimulation. We tested the hypothesis that coding sequence polymorphisms in the beta2AR gene contribute to the disease state in patients with cystic fibrosis. The Arg16Gly, Gln27Glu, and Thr164Ile beta2AR polymorphisms were studied by specific polymerase chain reaction and restriction fragment length polymorphism analysis in 126 cystic fibrosis patients. Forced expiratory volume in 1 s was significantly (P < 0.05) reduced in cystic fibrosis patients carrying the Gly16 allele in either homozygous or heterozygous form (Gly16Gly + Arg16Gly) compared to patients homozygous for the Arg16 allele (60.3 +/- 3.5% versus 75.7 +/- 4.9% predicted). Similarly, forced vital capacity and flows at lower lung volumes were significantly (P < 0.05 and P < 0.01) lower in cystic fibrosis patients carrying the Gly16 allele. In addition, the Gly16 allele was associated with a greater 5 year decline in pulmonary function (P < 0.01). Bronchodilator responses to albuterol were not significantly different between the groups. The Thr164Ile variant was found in four patients; these patients had markedly reduced pulmonary function. Isoproterenol-stimulated cyclic AMP formation was significantly blunted in cystic fibrosis patients carrying either the Gly16 allele or Thr164Ile genotype compared to cystic fibrosis patients homozygous for the respective Arg16 alleles. These data provide the first evidence suggesting that polymorphisms of the beta2AR gene contribute to clinical severity and disease progression in cystic fibrosis.  相似文献   
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0 引言为了克服离子选择电极(ISE)法的微量电位信号极易受环境温度变化及电子噪声的干扰问题,该仪器采用了参考电极,把参考电极与其测定电极装在同一测量室内,保持其相同的物理环境,使干扰源对所有电极的影响相同. 以内参液作为参考电极的测量对象,测得一个参考电极电位值,再测样品的电极电位值,二者相抵就消除了所叠加的干扰信号.  相似文献   
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Forty-six patients with recurrent ovarian cancer were reoperated, and cancer samples for the subrenal capsule assay (SRCA) were collected from 23 of them, whereas this test was not done in the remaining 23 control patients. The SRCA was evaluable in 22 cases (96%). Taken together, no significant difference appeared in the 3 years' survival figures between the groups: seven of 22 patients (32%) with the evaluable SRCA and six of 23 control patients (26%) were alive. However, a further analysis of the data revealed that the SRCA guided the selection of chemotherapy only in 15 patients, whereas tumour samples were resistant to all cytostatics tested in six cases and toxic side-effects limited the clinical application of the test results in the remaining one case. Four of the 11 patients (36%) whose further chemotherapy was strictly chosen based on the SRCA and seven of the 24 patients (29%) whose treatment was based on physician's choice survived at least 3 years. Our conclusion is that the SRCA is of limited value in the selection of second-line chemotherapy in recurrent ovarian cancer.  相似文献   
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ObjectiveThis study was performed to compare the acute effects of different endoluminal heating procedures, by which obstruction of insufficient veins could be induced in an established standardized experimental ex-vivo model.MethodsThe model consists of the subcutaneous foot vein from recently slaughtered cows. Different energy sources (laser and radiofrequency), application devices and energy application parameters were compared in an iterative optimizing process. Following energy application the vein tissue was harvested and prepared for histology.ResultsBy means of the developed ex-vivo model reproducible conditions for the application of endoluminal thermal energy were enabled in each specimen. Radiofrequency-treated veins showed macroscopic shrinkage, contraction of vessels and induration of tissue. Histologically a circumferential and homogenous thickening of the vessel wall could be described. Dependent on the laser treatment protocol, in-situ dissection of the treated veins showed a broad spectrum of effects. These effects ranged from blood deposits in perivascular tissue and perivascular thermal lesions to transmural coagulated vein tissue inducing obstruction of the lumen.ConclusionThis standardized model is applicable to investigate acute effects of endoluminal treatment protocols. Changes in the protocol could be easily performed and investigated in order to develop optimized treatment protocols. These ex-vivo experiments indicate that endovenous laser treatment should be modified and needs treatment standardization to ensure a controlled homogenous circumferential thermal damage.  相似文献   
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Objective Aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) may represent a treatment option for malignant brain tumors. We used a three-dimensional cell culture system, the C6 glioma spheroid model, to study acute effects of PDT and how they might be influenced by treatment conditions. Methods Spheroids were incubated for 4 h in 100 μg/ml ALA in 5% CO2 in room air or 95% O2 with subsequent irradiation using a diode laser (λ = 635 nm, 40 mW/cm2, total fluence 25 J/cm2). Control groups were “laser only”, “ALA only”, and “no drug no light”. Annexin V-FITC, a marker used for detection of apoptosis, propidium iodide (PI), a marker for necrotic cells and H 33342, a chromatin stain, were used for morphological characterization of PDT effects by confocal laser scanning and fluorescence microscopy. Hematoxylin–eosin staining and TdT-FragEL (TUNEL) assay were used on cryosections. Growth kinetics were followed for 8 days after PDT. Results PDT after incubation in 5% CO2 provided incomplete cell death and growth delay in spheroids of >350 μm diameter. However, complete cell death and growth arrest occurred in smaller spheroids (<350 μm). Incubation in 95% O2 with subsequent PDT resulted in complete cell death and growth arrest regardless of spheroid size. In incompletely damaged spheroids viable cells were restricted to spheroid centers. The rate of cell death in all control groups was negligible. Cell death was accompanied by annexin/PI costaining, but there was also evidence for annexin V-FITC staining without PI uptake. Conclusions PDT of experimental glioma results in rapid and significant cell death that could be verified as acute necrosis immediately after irradiation. This effect depended on O2 concentration and spheroid size.  相似文献   
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