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1.
The L-shell x-ray intensity ratios I(L β)/ I(L α) and I(L γ)/ I(L α) for elements with 73 ⩾ Z ⩽ 83 have been measured at photon incident energies of 17.8, 25.8 and 46.9 keV. The emitted x-rays were measured with a Si(Li) detector system. The results for Re, Pt and Tl are being reported for the first time. A comparison is made of the experimental results with the calculated values obtained by using the theoretical x-ray emission rates, subshell ionisation cross sections, subshell fluorescence yields and Coster-Kronig transition probabilities. The experimental results are in reasonable agreement with the theoretical values. 相似文献
2.
We compared the registration accuracy for corresponding anatomical landmarks in two MR images after fusing the complete volume (CV) and a defined volume of interest (VOI) of both MRI data sets. We carried out contrast-enhanced T1-weighted gradient-echo and T2-weighted fast spin-echo MRI (matrix 256×256) in 39 cases. The CV and a defined VOI data set were each fused using prototype software. We measured and analysed the distance between 25 anatomical landmarks in predefined areas identified at levels L 1–L 5 corresponding to defined axial sections. Fusion technique, landmark areas and level of fusion were further processed using a feed-forward neural network to calculate the difference which can be expected based on the measurements. We identified 975 landmarks for both T1- and T2-weighted images and found a significant difference in registration accuracy ( P<0.01) for all landmarks between CV (1.6±1.2 mm) and VOI (0.7±1.0 mm). From cranial (L 1) to caudal (L 5), mean deviations were: L 1 CV 1.5 mm, VOI 0.5 mm; L 2 CV 1.8 mm, VOI 0.4 mm; L 3 CV 1.7 mm, VOI 0.4 mm; L 4 CV 1.6 mm, VOI 0.6 mm; and L 5 CV 1.6 mm, VOI 1.6 mm. Neural network analysis predicted a higher accuracy for VOI (0.05–0.15 mm) than for CV fusion (0.9–1.6 mm). Deviations due to magnetic susceptibility changes between air and tissue seen on gradient-echo images can decrease fusion accuracy. Our VOI fusion technique improves image fusion accuracy to <0.5 mm by excluding areas with marked susceptibility changes. 相似文献
3.
Three carbohydrate conjugated dipicolylamine chelators, 2-bis(2-pyridinylmethyl)amino)ethyl 1-deoxy-1-thio-β-D-glucopyranoside ( L1), 2-bis(2-pyridinylmethyl)amino)ethyl-β-D-glucopyranoside ( L2), and 2-bis(2-pyridinylmethyl)amino)carboxamide-N-(2-amino-2-deoxy-D-glucopyranose) ( L3) were complexed to the [M(CO) 3] + core (M=Tc, Re) and the properties of the resulting complexes were investigated. Synthesis and characterization of the chelator 2-bis(2-pyridinylmethyl)amino)ethyl 1-deoxy-1-thio-β-D-glucopyranoside ( L1) and the corresponding Re complex are reported. All chelators were radiolabeled in high yield with [ 99mTc(CO) 3(H 2O) 3] + (>98%) and [ 186Re(CO) 3(H 2O) 3] + (>80%). The chelators and Re-complexes were determined to not be substrates for the glucose metabolism enzyme hexokinase. However, the biodistribution of each of the 99mTc complexes demonstrated fast clearance from most background tissue, including >75% clearance of the activity in the kidneys and the liver within 2 h post-injection. 相似文献
4.
IntroductionTranspedicular spinal fixation has recently been the focus of increased attention in several institutions throughout the world, but its safety and efficacy require a precise knowledge of the lumbar pedicles and their relations with neural structures. ObjectiveIn this study, it was aimed at studying the morphometry of the lumbar pedicle in Egyptian population for more safety and better efficacy during pedicle screw fixation and assessment of the accuracy of CT pedicle measurements. Patients and methodsStudy of the lumbar pedicles was conducted using CT scanning for lumbar blocks of five cadavers together with 75 cases of lumbar disc patients to clarify the lumbar pedicle morphology in Egyptian population. Measurements of the axial length, the axial angle, the pedicle breadth, and endosteal thickness were performed on CT images obtained at the middle of the cranio-caudal axis of the pedicle of patients and cadavers. Moreover, these measurements were reviewed by direct caliper measurements in these cadavers. ResultsThis study illustrated that the axial length of pedicles is around 5 cm at all lumbar levels with negligible shortening at L 4 and L 5. The angels of inclination of the lumbar pedicle axis on the midline are more obtuse than the known Western measurements and becoming more obtuse from L 1 to L 5. The study clarified that the pedicle breadth becomes progressively thicker from L 1 (6.6 mm) to L 5 (18.5 mm) and the endosteal thickness follows the pedicle breadth becoming thicker at L 5 (8.3 mm) than at L 1 (3.8 mm). We could not detect any statistically significant difference between all the above-mentioned measurements when we compared the direct caliper measurements of the cadavers with its CT measurements and with patients CT measurements. Wide range of measurements of the lumbar pedicle for each particular level was noticed. ConclusionCT pedicle measurements are accurate indicators for the actual pedicle morphometry. The Egyptian lumbar pedicles differ in some aspects from the pedicles of other populations. The pedicle screw diameter, the screw length, and the angle of its insertion are better to be tailored according to the CT pedicle measurements of each patient. 相似文献
5.
The results of recycle size-exclusion and anion-exchange chromatography are combined to determine molecular weights and radii of gyration for selected components of a carrier-added technetium hydroxyethylidene diphosphonate radiopharmaceutical bone-imaging preparation. Samples evaluated by size-exclusion are selected from fractions collected as the preparation elutes from the anion-exchange column. Polyethylene glycol and polyphosphate molecular weight standards are used, in conjunction with the universal calibration method, to determine Mark-Houwink constants and to estimate molecular weights for the complexes. The results of this study support a spherical shape model for the collection of technetium complexes. Given the combined knowledge of molecular weights, charges, technetium concentration dependencies, and mass spectral data, several formula assignments are proposed, including TcO(OH)L −1, Tc 2O(OH) 6L −3, Tc 2O(OH) 2L 3−6, Tc 3O 2(OH) 3L 2−5, Tc 3O 2(OH) 3L 3−7, Tc 2O 2(OH) 4(HL) 3−7 and Tc 2O 2(OH) 4(H 2L) 4−8. 相似文献
6.
Identification of living undocumented individuals highlights the need for accurate, precise, and reproducible age estimation methods, especially in those cases involving minors. However, when their country of origin is unknown, or it can be only roughly estimated, it is extremely difficult to apply assessment policies, procedures, and practices that are accurate and child-sensitive. The main aim of this research is to optimize the correct classification of adults and minors by establishing new cut-off values for four different continents (Africa, America, Asia, and Europe). For this purpose, a vast sample of 10,701 orthopantomographs (OPTs) from four continents was evaluated. For determination and subsequent validation of the new third molar maturity index (I3M) cut-off values by world regions, a cross-validation by holdout method was used and contingency tables (confusion matrices) were generated. The lower third molar maturity indexes, from both left and right side (I3ML and I3MR) and the combination of both sides (I3ML_I3MR) were calculated. The new cut-off values, that aim to differentiate between a minor and an adult, with more than 74.00% accuracy for all populations were as follows (I3ML; I3MR; I3ML_I3MR, respectively): Africa = (0.10; 0.10; 0.10), America = (0.10; 0.09; 0.09), Asia = (0.15; 0.17; 0.14), and Europe = (0.09; 0.09; 0.09). The higher sensitivity (Se) was detected for the I3ML for male African people (91%) and the higher specificity (Sp) of all the parameters (I3ML; I3MR; I3ML_I3MR) for Europeans both male and female (> 91%). The original cut-off value (0.08) is still useful, especially in discriminating individuals younger than 18 years old which is the goal of the forensic methods used for justice. 相似文献
7.
Objective The aim of this study was to evaluate a 3D tumor segmentation method for fluorodeoxyglucose positron emission tomography (FDG-PET)
in the context of noninvasive estimation of tumor metabolic length ( L
m), as it correlates with surgical pathology and phantom results.
Methods Thirty-four patients (7 women, 27 men) with esophageal cancer were retrospectively evaluated. All patients underwent FDG-PET-computed
tomography (CT) imaging following endoscopic ultrasound (EUS). Seventeen patients had esophagectomy after PET/CT, without
prior neoadjuvant therapy. Tumor length was assessed by EUS ( L
e, n = 31) and histopathology ( L
p, n = 17). Images were evaluated quantitatively with a 3D threshold-based region-growing program (Medical Image Processing Analysis
and Visualization). L
m, total metabolic volume ( V
m), maximum standardized uptake value (SUV max), and average SUV (SUV a) over the entire tumor were obtained for several threshold values (mean activity in the liver plus 0-, 1-, 2-, 3-, and 4-SD
of the activity in the liver).
Results
L
m showed a good correlation with L
p for all thresholds (best correlation for L
m(2-SD), r = 0.74, P < 0.001). A positive nonsignificant correlation was observed between L
p and L
e ( r = 0.30, P = 0.29). L
m(2-SD) correlated well with L
e ( r = 0.71, P < 0.001). Good correlations were also observed between L
m(2-SD) and V
m(2-SD) ( r = 0.89, P < 0.001) and SUV a(2-SD) ( r = 0.38, P < 0.05). V
m(2-SD) also had a significant correlation with L
p ( r = 0.61, P < 0.05) and L
e ( r = 0.57, P < 0.001).
Conclusions FDG-PET-derived tumor metabolic length of untreated esophageal carcinomas correlates well with surgical pathology results,
and provides preliminary evidence that noninvasive delineation of the superior and inferior extent of viable tumor involvement
might be feasible using computer-generated metabolic length measurements. 相似文献
8.
To determine the influence of androgen receptor CAG and GGN repeat polymorphisms on fat mass and maximal fat oxidation (MFO), CAG and GGN repeat lengths were measured in 128 young boys, from which longitudinal data were obtained in 45 of them [mean ± SD: 12.8 ± 3.6 years old at recruitment, and 27.0 ± 4.8 years old at adult age]. Subjects were grouped as CAG short (CAG S) if harboring repeat lengths ≤ 21, the rest as CAG long (CAG L); and GGN short (GGN S) if GGN repeat lengths ≤ 23, or long if > 23 (GGN L). CAG S and GGN S were associated with lower adiposity than CAG L or GGN L ( P < 0.05). There was an association between the logarithm of CAG repeats polymorphism and the changes of body mass ( r = 0.34, P = 0.03). At adult age, CAG S men showed lower accumulation of total body and trunk fat mass, and lower resting metabolic rate (RMR) and MFO per kg of total lean mass compared with CAG L ( P < 0.05). GGN S men also showed lower percentage of body fat ( P < 0.05). In summary, androgen receptor CAG and GGN repeat polymorphisms are associated with RMR, MFO, fat mass, and its regional distribution in healthy male adolescents, influencing fat accumulation from adolescence to adult age. 相似文献
9.
The objective of this work was to evaluate the maximum luminance ( L max) level of medical liquid crystal displays (LCDs) as a function of backlight hours (BLH) annually. The L max values for 249 2-megapixel color LCDs (RadiForce RX210, EIZO Corporation) were measured in February 2014, 2015, and 2016. Four near-range luminance meters and the built-in type luminance meters, each with an LCD, were used for the measurements. The average and standard deviation (SD) of BLH measured in 2014 was 15,371 ± 8219 h. Four, twenty, and thirty-nine LCDs failed in the constancy tests performed in February 2014, 2015, and 2016, respectively, i.e., they were unable to output 170 cd/m 2. The SD of L max increased each year and as BLH became longer. In conclusion, evaluation of L max as a function of BLH during constancy testing will help predict the decrease in L max of a clinically used medical color LCD. 相似文献
10.
Summary Two cases of cervical spondylolisthesis, due to a congenital defect in the pars interarticularis of C 6, associated with spina bifida and elongation of the contralateral pars interarticularis, are reported. Tomography showed an abnormal direction of the articular facets of C 6 and demonstrated a narrow frontal diameter of the cervical spinal canal at the level of the malformation. Gas myelography showed a slight compression of the cord. Unlike previously reported cases the patients had neurological findings which, in one case at least, were certainly referable to the spinal cord. 相似文献
12.
The aim of this study was to improve the understanding of interdependencies of dynamic changes in central airway dimensions, lung area and lung density on HRCT. The HRCT scans of 156 patients obtained at full inspiratory and expiratory position were evaluated retrospectively. Patients were divided into four groups according to lung function tests: normal subjects ( n=47); obstructive ( n=74); restrictive ( n=19); or mixed ventilatory impairment ( n=16). Mean lung density (MLD) was correlated with cross-sectional area of the lung (CSA L), cross-sectional area of the trachea (CSA T) and diameter of main-stem bronchi (D B). The CSA L was correlated with CSA T and D B. MLD correlated with CSA L in normal subjects ( r=–0.66, p<0.0001) and patients with obstructive ( r=–0.62, p<0.0001), restrictive ( r=–0.83, p<0.0001) and mixed ventilatory impairment ( r=–0.86, p<0.0001). The MLD correlated with CSA T in the control group ( r=–0.50, p<0.0001) and in patients with obstructive lung impairment ( r–0.27, p<0.05). In patients with normal lung function a correlation between MLD and D B was found ( r=–0.52, p<0.0001). CSA L and CSA T correlated in the control group ( r=0.67, p<0.0001) and in patients with obstructive lung disease ( r=0.51, p<0.0001). The CSA L and D B correlated in the control group ( r=0.42, p<0.0001) and in patients with obstructive lung disease ( r=0.24, p<0.05). Correlations for patients with restrictive and mixed lung disease were constantly lower. Dependencies between central and peripheral airway dimensions and lung parenchyma are demonstrated by HRCT. Best correlations are observed in normal subjects and patients with obstructive lung disease. Based on these findings we postulate that the dependencies are the result of air-flow and pressure patterns. 相似文献
13.
Zusammenfassung Es werden drei tödliche Vergiftungen mit dem Desinfektionsmittel C 4 beschrieben. Sie gehören auf Grund der Applikationsart zu den bisher seltenen Fällen.Einer 42jährigen und 43jährigen Frau wurden infolge Verwechselung mit Wofacutanlösung Einläufe mit einer 3 % igen C 4-Lösung nicht bekannter Menge verabreicht. — Im dritten Fall handelte es sich um einen Abtreibungsversuch einer 33jährigen Frau mit C 4-Lösung. Menge und Konzentration des verwendeten Desinfektionsmittels blieben unbekannt.Der Tod trat in allen Fällen sehr schnell ein.Die Obduktionsergebnisse und das Ergebnis der toxikologisch-chemischen Untersuchungen werden mitgeteilt. Dabei konnte bei einer vaginalen Intoxikation zum ersten Mal der Nachweis der Wirkstoffe auch in den II. Giftwegen geführt werden. Der Wirkungsmechanismus der C 4-Intoxikation wird an Hand der vorliegenden Literatur diskutiert.
Summary Three fatal cases of intoxication by the desinfectant C4 (Alkyl-dimethylbenzylammoniumchloridgemisch) are reported. The unusual mode of administration of the poison render these cases as rare. In two cases the desinfectant was erroneously administered via enema, using a 3 % solution in unknown amounts. In the third case the desinfectant was used in an attempt to secure abortion. Concentration and amount were unknown. In all three cases death occured very rapidly. The findings at autopsy and the result of the chemical-toxicological analyses are reported. Identification of the toxic substances in the abortion cases was possible. The mode of action of C4 is discussed in the light of the available literature. 相似文献
14.
In forensic toxicology, immunoassays for drug screening are widely used because of the simple test procedures and instantaneous outcome of results. However, commercial immunoassay products are available for only a limited number of drugs. Preparation of antidrug antibodies is a crucial, but time-consuming in creating an immunoassay system. In this study, we focused on the application of a single-chain variable fragment (scFv) antibody for drug screening and developed a fluvoxamine (FLV) detection system for indirect competitive enzyme-linked immunosorbent assay (icELISA) using the scFv against FLV. To clarify the influence of domain order on the scFv binding activities, we prepared two kinds of scFv with different domain orders (HL, V H-linker-V L, and LH, V L-linker-V H) and examined their kinetic parameters against FLV. The scFvs showed sufficient FLV binding activities ( K D = 3.8 and 7.6 nM), and the HL scFv was slightly more favorable for FLV binding than the LH scFv. The developed icELISA using the HL scFv could detect FLV in the range of 10–200 ng/mL, and the scFv has no cross-reactivity below 100 μM except for chlorpromazine and imipramine. We also quantified the plasma FLV concentrations in forensic autopsy cases, and the results showed that this method could be applied effectively for FLV quantification without the need for extraction steps. Although recombinant antibodies against small molecule drugs for immunoassays have not yet been commonly used, we can predict that they could be a powerful tool to screen drugs in the near future, because of their advantages. 相似文献
15.
It is extremely important to have a good grasp of the acceptable limit of hepatectomy before operation because postoperative
liver failure can take a fatal course; however, baseline data on the limit of hepatectomy have not been clearly defined. We
therefore evaluated and compared the predicted remnant liver function obtained by computed tomography(CT) and technetium-99m
diethylenetriamine penta-acetic acid-galactosyl human serum albumin ( 99mTc-GSA) liver scintigraphy in order to obtain precise data regarding remnant liver function before hepatectomy. We investigated
20 patients undergoing hepatectomy using the clearance rate of indocyanine green (KICG) as a parameter, and compared the predicted
postoperative KICG obtained by CT and by transaxial single-photon emission tomographic (SPET) images acquired by 99mTc GSA liver scintigraphy before hepatectomy. In GSA studies, based on time-activity curves for the heart and liver, we compared
HH15 (heart activity at 15 min divided by heart activity at 3 min), LHL15 (liver activcity at 15 min divided by heart plus
liver activity at 15 min) and K L (obtained from the time-activity curve for the liver) in 103 patients. In 58 patients without increased serum bilirubin,
K L was compared with KICG. In four patients, occlusion of the right portal vein was performed with the aim of carrying out secondary
hepatectomy, and changes in liver volume were compared between CT and 99mTc GSA liver scintigraphy. The correlation coefficient between the postoperative KICG predicted by CT and the actual postoperative
KICG was rather poor, at r = 0.569 ( P<0.05); that between the postoperative KICG predicted by 99mTc GSA liver scintigraphy and the actual postoperative KICG was good, at r = 0.788 ( P<0.01); correlations between K L and HH15 and between K L and LHL15 in 103 patients were very good or good, at r = 0.906 ( P<0.001) and r = 0.807 ( P<0.001), respectively, and that between K L and KICG in 58 patients was very good, at r = 0.916 ( P<0.001). In all four cases of right portal vein occlusion, the remnant liver volume ratio was markedly increased after occlusion
in GSA compared with CT, and the postoperative KICG predicted by GSA after occlusion was closer to the actual postoperative
KICG than that predicted by CT. It is concluded that 99mTc GSA liver scintigraphy is useful for predicting remnant liver function before hepatectomy and for evaluating changes in
regional liver function after occlusion of the portal vein unilaterally.
Received 20 March and in revised form 24 June 1998 相似文献
16.
PurposeThis study compared the applicator position relative to the tracheal wall and dosimetric parameters between conventional and novel applicators among patients receiving endobronchial brachytherapy (EBBT) for intratracheal tumors. Methods and MaterialsData from 7 patients who received EBBT for intratracheal tumors were retrospectively analyzed; 4 and 3 patients were treated with conventional (2-wing) or novel (5-wing) applicators, respectively. Applicator centrality was evaluated using the distance between the center of the trachea and main bronchus (TMB) lumen and path of source ( L). Dosimetric parameters, including plans normalized to D2cc of the TMB = 45 Gy (normalized plan), were compared between the applicators. ResultsThe mean and maximum values of L in cases of the 2-wing applicator group were approximately 5.0 mm and 10.0 mm, respectively. In the novel applicator group, the corresponding values were approximately 3.0 and 6.0 mm, respectively. In the normalized plan of the 2-wing applicator group, the ranges of median V 90% of clinical target volume (CTV) and D 0.1cc of the TMB in all cases were 23.0–91.9% and 66.3–153.1 Gy, respectively. In the 5-wing applicator group, the corresponding values were 69.2–83.8% and 60.4–84.5 Gy, respectively. ConclusionsIn the 5-wing applicator group, the range was narrow in all dose–volume parameters except for D2cc of the TMB. Compared to the conventional applicator, the 5-wing applicator can give a stable dose to the CTV and can reduce the maximum dose of the TMB. This suggests that stable EBBT can be given to any patient using the 5-wing applicator. 相似文献
17.
Purpose:The aim of this study was to investigate whether the detectability of brain volume change in voxel-based morphometry (VBM) with gray matter images is affected by mild white matter lesions (MWLs). Methods:Three-dimensional T 1-weighted images (3D-T 1WIs) of 11 healthy subjects were obtained using a 3T MR scanner. We initially created 3D-T 1WIs with focal cortical atrophy simulated cortical atrophy in left amygdala (type A) and the left medial frontal lobe (type B) from control 3D-T 1WIs. Next, the following three types of MWL images were created: type A + 1L and type B + 1L images, only one white matter lesion; type A + 4L and type B + 4L images, four white matter lesions at distant positions; and type A + 4L * and type B + 4L * images, four white matter lesions at clustered positions. Comparisons between the control group and the other groups were performed with VBM using segmented gray matter images. Results:The gray matter volume was significantly lower in the type A group than in the control group, and similar results were observed in the type A + 1L, type A + 4L, and type A + 4L * groups. Additionally, the gray matter volume was significantly lower in the type B group than in the control group, and similar results were observed in the type B + 1L, type B + 4L, and type B + 4L * groups, but the cluster size in type B + 4L * was smaller than that in type B. Conclusion:Our study showed that the detectability of brain volume change in VBM with gray matter images was not decreased by MWLs as lacunar infarctions. Therefore, we think that group comparisons with VBM should be analyzed by groups including and excluding subjects with MWLs, respectively. 相似文献
18.
Zusammenfassung Verff. berichten über Resultate von M-N-Untersuchungen in 6588 Rechtssachen aus Ungarn. In 9,64% der Sachen bzw. in 8,3% der beteiligten Männer gelang es allein mittels M-N-Untersuchungen einen Vaterschaftsausschluß zu erreichen. In Kenntnis der ungarischen Genfrequenzen des M-N-Systems ergibt die maximale Vaterschaftsausschluß chance 18,49%. Außerdem wird über 5 Fälle berichtet, in denen das schwache N 2-Merkmal vorhanden ist, und zwar bei einer Person im Phänotyp N 2, bei den 5 anderen im Phänotyp MN 2, wodurch die Häufigkeit des Vorkommens des schwachen Merkmals N 2 auf etwa 1:12000 geschätzt wird.
Summary 6588 cases are reviewed. In 9,64% of the cases (8.3% of the men) exclusion of paternity was possible by M-N determinations alone. Maximal possible paternity exclusion in Hungary (by means of the M-N system) is 18.49%. Five cases are reported with a weak N2 trait. The occurrence of weak N2 phenotype is estimated at about 1:12.000. Gegenwärtige Arbeitsstelle: Bezirkspoliklinik inSzigetszentmiklós. 相似文献
19.
This work was aimed at the development and validation of an economical colorimetric method for detection of cyanide in whole blood. The method was based on the reaction of hydrogen cyanide with vitamin B12. The hydrogen cyanide is released on acidification of the blood sample. The vitamin B12 was loaded on a strip of a commonly used filter paper by impregnating the strip in a 1.0% (w/v) solution of vitamin B12 under alkaline conditions. The limit of detection of this method was found to be 1.0 mg L ?1 which is lower than the reported lethal blood concentration of cyanide (2.5 mg L ?1). The method was free from interferences from the common gases including ammonia, carbon dioxide, arsine, phosphine and carbon monoxide, thiocyanate, organophosphate pesticides and nitrile-containing pesticides. This method was successfully employed for detection of cyanide in several cases reported to the forensic toxicology. 相似文献
20.
Zusammenfassung Es wird über die Phänotypenverteilung im Transferrinsystem bei 699 nichtkorrelierten Personen berichtet. Die seltenen Varianten B 1C, B 2C und CD 2 werden näher beschrieben und der Wert für die Vaterschaftsbegutachtung diskutiert.
Summary The phenotypes found in a random sample of 699 non-consanguineous persons from West Berlin is reported. The rare variants B1C, B2C and CD2 are described and their significance in paternity cases is discussed. Herrn Professor Dr. W. Krauland zu seinem 60. Geburtstag am 10. April 1972 gewidmet. 相似文献
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