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991.
The aim of this study was to investigate the effect of molecular weight on the topical migration and systemic absorption of drugs, sodium salicylate (SA), calcein sodium (CAL) and FITC-dextrans (FD-4, FD-10, FD-20 and FD-40), after intracutaneous (i.c.) injection. The apparent diffusion coefficients in the skin (D(s)) of SA, CAL and FD-4 after i.c. injection were almost the same and slightly less than 1x10(-4)cm(2)/min. The D(s) value drastically decreased with molecular weight more than 10kDa. The plasma concentration-time curve after i.c. injection was predicted by the convolution method. The ratio of AUC (observed/predicted) was approximately unity for SA, CAL and FD-4 although the systemic absorption of only FD-4 was delayed. In contrast, the AUC ratios of FD-10, FD-20 and FD-40 were about 0.5, 0.2 and 0.06, respectively, and obviously decreased with the molecular weight. The elimination of FD-10, FD-20 and FD-40 from the skin was slow and the drugs tended to remain in the muscle. These results indicated the importance of diffusion in the skin and permeability through the blood vessels for local migration and systemic absorption of drugs after penetration into viable skin.  相似文献   
992.
[目的]了解城市交通区不同地区和不同时间内颗粒物中多环芳烃的分布特征。[方法]对某城市某交通区不同地点颗粒物和多环芳烃的含量分别进行了监测,同时在1个地点进行了连续24h监测。[结果]不同地段颗粒物中多环芳烃的含量不同,总体趋势是:高架下大气中颗粒物多环芳烃的污染比高架上严重;城区比郊区污染严重;隧道内比隧道外污染严重。同时,同一地点颗粒物及其中多环芳烃连续24h的监测结果表明,在24h内,大气中颗粒物及其中的多环芳烃含量有规律的波动,在清晨、下午出现两个高峰。研究还发现在颗粒物和其中多环芳烃之间存在明显的相关性,相关系数为0.231,并得到了回归模型;对不同粒径的成分分析结果表明,PM2.5占PM10的30%~50%,是主要的多环芳烃携带颗粒物。[结论]交通因素以及周围环境因素是导致大气中颗粒物多环芳烃污染浓度改变的主要因素之一;PM2.5是主要的多环芳烃的携带者。  相似文献   
993.
Summary In an 18-year-old male with Eisenmenger syndrome cyanosis and erythrocytosis were increasing. The erythrocytosis diminished following oral bunazosin and phlebotomy was not needed during the treatment. When bunazosin was stopped, the erythrocytosis increased, but when it was resumed, the erythrocytosis and general fatigue diminished.  相似文献   
994.
Summary An 11-year-old girl with congenital atresia of the left coronary ostium underwent coronary artery bypass grafting using the internal mammary artery. Before surgery, the patient complained of syncope on exertion. Exercise electrocardiogram (ECG), two-dimensional echocardiogram, and201Tl myocardial scintigram were useful in establishing the diagnosis. Selective coronary angiograms showed typical findings. Postoperative recovery was uneventful; exercise ECG and stress201Tl myocardial scintigram demonstrated improvement. Internal mammary artery graft is probably better than a saphenous vein graft as a coronary artery bypass graft in childhood and adolescence because of the long-term patency of this type of graft.  相似文献   
995.
We carried out a randomized, single-blind, cross-over trial to compare the antiemetic effect, for both acute and delayed emesis, of granisetron plus dexamethasone (GRN+Dx) with that of high-dose metoclopramide plus dexamethasone (HDMP + Dx). Fifty-four patients with primary or metastatic lung cancer, given single-dose cisplatin (> 80 mg/m2) chemotherapy more than twice, were enrolled in this study. They were treated with both HDMP+Dx and GRN+Dx in two consecutive chemotherapy courses. On day 1, patients experienced a mean of 2.5 (SD=4.3) and 0,1 (SD = 0.4) episodes of vomiting in the HDMP+Dx and the GRN + Dx groups, respectively ( P =0.0008). Complete response rate on day 1 was 45 and 90% in the HDMP+Dx and the GRN+Dx groups, respectively ( P = 0.0001). Patients treated with GRN+Dx had a tendency to suffer more episodes of vomiting than the HDMP+Dx group on days 2–5, but it was not statistically significant. Twenty-four patients (57%) preferred the GRN+Dx treatment and 14 patients (33%), HDMP + Dx. In the HDMP + Dx group, nine patients (21%) had an extrapyramidal reaction, and 5 patients (12%) had constipation that lasted for at least two days. In contrast, no patients had extrapyramidal reactions, and IS patients (43%) had constipation in the GRN+Dx group ( P < 0.01). GRN+Dx was more effective than HDMP+Dx only in preventing the acute emesis induced by cisplatin. An effective treatment for delayed emesis is still needed.  相似文献   
996.
In this study, we aimed to develop a population pharmacokinetic model for CPT-11 and to use the Bayesian method to estimate CPT-11 pharmacokinetic parameters in each of 43 patients who received combined therapy consisting of CPT-11 and etoposide. The group was divided into first and second data sets of 30 and 13 patients, respectively. We developed a population pharmacokinetic model of CPT-11 based on the first data set. The individual pharmacokinetic parameters [area under the concentration curve (AUC) and clearance (CD] were subsequently estimated by using the Bayesian method on the second data set. Plasma CPT-11 concentrations were measured by high-performance liquid chromatography, and compartmental pharmacokinetic models were fitted by the Bayesian method. The population pharmacokinetic model was developed by using the nonlinear mixed effect model. We selected the volume of the central compartment (Vc), CL, and distribution rate constants (K12, K21) as population pharmacokinetic parameters. The population mean values (CV%) of Vc, CL, K12, and K21 were, respectively, 31.8 (15.7%) liter/m2,14.1 (27.8%) liter/h/m2,1.1 (8.4%)/h, and 0.41 (30.3%)/h. Residual intraindivirtual variability was 22.9%. The optimal sampling regime for estimation of the AUC and CL in using the Bayesian method was the two time points of 1 and 8 h post infusion. The mean predictive error, the mean absolute predictive error, and the root mean squared error were -3.3, 9.4, 3.2% (AUC) and 6.3, 10.0, 3.5% (CL), respectively. We concluded that the AUC and CL of CPT-11 could be estimated from plasma concentrations at two times by using the Bayesian method.  相似文献   
997.
998.
The outcome of fetuses with diaphragmatic hernia (CDH) has been reported to be related to the severity of lung hypoplasia. As an index of pulmonary hypoplasia, we attempted to measure the lung-thorax transverse area ratio (L/T) using ultrasonic echography in eight fetuses with left-sided CDH. Two cases with L/T more than 0.28 (controls: 0.52±0.04) were transported postnatally and recovered after early operation without episodes of persistent fetal circulation. Elective surgical repair was performed in six infants immediately after cesarean delivery at 35–37 weeks' gestation. In three cases with L/T between 0.21 and 0.24 who recovered with no complications, surgical reduction of the abdominal organs improved arterial blood gases and high-frequency oscillation ventilation (HFOV) was fully effective for respiratory management. In three with L/T between 0.11 and 0.17, extracorporeal membrane oxygenation (ECMO) was required from the 1st to the 12th postoperative day despite HFOV. Although two infants died of combined cardiovascular anomalies and airway bleeding caused by prolonged HFOV, respectively, one infant with minimal L/T survived. Measurement of L/T may help to predict the outcome of fetuses with CDH and to determine the indications for various treatments including immediate operation after cesarean delivery, HFOV, and ECMO. Offprint requests to: S. Kamata  相似文献   
999.
A measles outbreak occurred in the Chikuhou district of Fukuoka, Japan from May to October 1990, during which 71 patients were cared for at the Itoda Public Hospital. Hospital records revealed a large outbreak in the adjacent town of Kanada. In order to characterize the outbreak, questionnaires were sent to all preschool-age children in Itoda (73% effective response) and in Kanada (76% effective response) requesting information about their vaccination and/or history of measles. The number of patients was 22 (4%) in Itoda and 63 (14%) in Kanada, most of these being preschoolers, while the vaccination rate was 61% and 44%, respectively. The herd immunity levels in age-specific groups were compared between the two towns. Before the epidemic, the immunity level of 1 year old children in Kanada, who showed the higher attack rate, was lower (18%) than that in Itoda (39%), while after the epidemic it rose above 60% in both towns. When we studied the correlation between the attack rate and the vaccination rate, or the number of children susceptible to measles (susceptibility rate) in each preschool, the attack rate correlated negatively with the vaccination rate (correlation coefficient [CC] = - 0.818; P < 0.01), and positively with the susceptibility rate (CC 0.860; P < 0.01). The regressed equation on the correlation indicated that the immunity level should be more than 70% to keep the attack rate under 5% in preschoois. After the epidemic, the immunity levels of all preschoolers reached above 70%. Early vaccination should be given to at least 70% of young preschoolers in order to prevent a large outbreak of measles under the present vaccination program in Japan.  相似文献   
1000.
Recent molecular studies have revealed that a 22q11 deletion is frequently detected in DiGeorge syndrome (DGS), velo-cardio-facial syndrome (VCFS), and conotruncal anomaly face syndrome (CTAFS). As one of the major clinical manifestations in these three syndromes is conotruncal cardiac malformation, we prospectively studied the frequency of a 22q11 deletion in a group of patients with conotruncal cardiac malformation. Fluorescence in situ hybridization (FISH) analyses using N25 (D22S75) DiGeorge Chromosome Region probe were performed on 64 patients with conotruncal cardiac malformation, who visited our clinic from October 1993 to January 1994. Of the 64 patients studied, a 22q11 deletion was detected in 5 patients (7.8%): 3 out of 30 patients with tetralogy of Fallot, one of three with interruption of the aortic arch, and one hemitruncus patient. No deletion was found in 16 patients with complete transposition of the great arteries, 8 with double outlet right ventricle and 2 with aortopulmonary window. In these five patients with 22q11 deletion, patient 1 was clinically diagnosed as having DGS, patients 2 and 3 had CTAFS, and patient 4 had VCFS. Patient 5 could not be dysmorphologically evaluated. It was noteworthy that all patients with a 22q11 deletion, except a non-evaluated patient, had some symptoms of syndromes DGS, CTAFS or VCFS, and that we failed to identify a non-syndromic 22q11 deletion positive patients in the present series of 64 patients.Conclusion This study suggests that it is advisable to bear 22q11 deletion in mind when a patient with conotruncal cardiac anomalies has some other features of DGS, VCFS or CTAFS.  相似文献   
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