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Abstract: The effects of pyridoxalated hemoglobin polyoxyethylene conjugate (PHP) and stroma-free hemoglobin (SFH) on vascular responsiveness to various vasoactive substances were examined in isolated perfused rat kidneys. The kidneys isolated from rats were perfused with 6% PHP, 6% SFH, and 6% hydroxyethylstarch (HES) solution at a constant flow rate. Vascular responsiveness to acetylcholine (ACh), nitroglycerin (NG), norepinephrine (NE), and angiotensin-II (ANG-II) was examined by measuring the perfusion pressure (PP). Effects of inhibition of endothelium-derived relaxing factor (EDRF) by NG-monomethyl L-arginine (L-NMMA) on NE-induced and ANG-II-induced renal vascular responses were examined. ACh and NG induced a dose-dependent decrease in perfusion pressure (PP) in all groups. NE and ANG-II induced an increase in PP in all groups, but NE-induced and ANG-II-induced responses in the PHP-perfused and SFH-perfused groups were significantly larger than those in the HES-perfused group. L-NMMA did not alter vascular responsiveness to NE and ANG-II. These results indicate that PHP and SFH do not inhibit EDRF induced by ACh, but hemoglobin moiety per se does augment the vascular responsiveness to NE and ANG-II in the isolated perfused rat kidney.  相似文献   
23.
Due to the great advancements in fetal ultrasonography, the number of prenatal diagnoses are increasing, greatly contributing to improved neonatal surgery. It is now relatively easy to detect huge fetal cystic masses, and we have experienced three cases with a huge neck tumor detected in utero, one case with teratoma and two cases with cystic hygroma. Each case was complicated by neonatal asphyxia, and the neonate needed resuscitation by means of endotracheal intubation. The infant with teratoma unfortunately died of respiratory distress due to compression of the trachea before a perinatal team could be organized. Although the remaining cases with cystic hygroma were treated by a perinatal team, one died 19 hours after birth and the other has survived with the aid of endotracheal intubation in the hospital for three years. In addition, all four cases of cystic hygroma detected antenatally in our institute, which were not delivered, also had fetal hydrops which suggested a general lymphatic derangement. Cystic hygroma detected in utero is considered to be different from that detected after birth, since the former is associated with genetic lymphatic derangement. Prenatal diagnosis enables such patients to survive the perinatal period, but may not improve the prognosis of fetal cystic hygroma so much.  相似文献   
24.
Incorporation of hydroxypropylcellulose (HPC-)doxorubicin, which we developed as a mucous-membrane-adhesive drug preparation, was instilled into the urinary bladder in 10 clinical cases. Tumor of the urinary bladder was a single tumor in all 10 cases, and preclinical histology showed transitional cell carcinoma, grade 1 or 2, and a lower stage than T1. HPC-doxorubicin, 20 mg/20 ml, was administered in 5 cases, and the other 5 cases received the conventional aqueous doxorubicin, 20 mg/20 ml by way of a catheter and the urethra. Cold punch biopsy was performed after 3 days of instillation, and the incorporation of doxorubicin into both tumorous and normal tissue was measured by high-pressure liquid chromatography. After 3 days, it was found that in the HPC-doxorubicin-administered group, doxorubicin was detected in both tumorous and normal tissue, but it was not detected in either tissue after aqueous doxorubicin administration. In 5 cases of the HPC-doxorubicin group, doxorubicin levels in the tumorous and normal tissue were examined, and it was found that significantly more doxorubicin was detected in the tumorous tissues. Thus, it may be said that our HPC-doxorubicin remained longer within the urinary bladder than the conventional aqueous doxorubicin preparation. Instilled HPC-doxorubicin is more highly concentrated in the tumorous tissue than in the normal bladder tissue, and thus, HPC-compounded anticancer drugs may be therapeutically more useful.  相似文献   
25.
The reverse U incision method has been employed for the correction of the unilateral cleft lip nose deformity for more than twenty years with satisfactory results. It has some columella lengthening effect and thus has proved to be useful for the correction of nasal deformities of bilateral cleft lip. To augment its columella lengthening effect a columella relaxation incision is added to the bilateral reverse U incision for the correction of the bilateral cleft lip nose deformity. This results in a reconstructed columella of satisfactory length and width.  相似文献   
26.
A murine monoclonal antibody (MDR3M) (isotype: IgM) reactive with mdr3 gene product was generated by immunizing mice with mdr3 -specific peptide (H2N-12WRPTSAEGDFELGISSKQKRKKTKTVKMI41G-COOH) and hybridizing the primed mouse splenic B cells with X63-Ag8,6.5.3 mouse plasmacytoma cells. MDR3M did not cross-react with mdr1 gene product. This monoclonal antibody may be useful for analyzing the role of mdr3 gene product in cells and tissues.  相似文献   
27.
The purpose of this study was to determine the relationship between segmental hyperintensity of the liver on T1-weighted images and segmental cholestasis in patients with obstructive jaundice. T1-weighted and T2-weighted MR images were obtained of 73 patients with obstructive jaundice caused by various diseases. Fat-suppressed T1-weighted images were also obtained of 10 patients. Eleven patients with segmental intra-hepatic bile duct dilatation (cholestasis) showed segmental hyperintensity on T1-weighted images and/or fat-suppressed T1-weighted images and no signal intensity difference on T2-weighted images. Sixty-two patients with widespread intrahepatic bile duct dilatation showed no intensity difference on T1-weighted and T2-weighted images (P < .01). Segmental hyperintensity on T1-weighted images was correlated with intrahepatic cholestasis.  相似文献   
28.
A 6-year-old boy was successfully operated on for double outlet ventricle, common atrioventricular canal with severe valvular regurgitation, right atrial Isomerism, L-loop ventricles, total anomalous pulmonary venous connection, and pulmonary stenosis with hypoplastic left pulmonary artery. The Interventricular rerouting from the left ventricle to the ascending aorta was performed with a spiral patch, the lnteratrlal switching was performed by a Mustard patch, the common atrioventricular orifice was partitioned and valve repair was performed, and an 18-mm valved conduit was inserted between the right ventricle and the pulmonary artery. Although the patient had a small residual ventricular septal defect and pulmonary stenosls, the patient Is alive and well.  相似文献   
29.
Thallium lung uptake (TL-uptake) was usually treated as background for myocardial image and increase of TL-uptake in exercise test was considered as marker of depressed cardiac function. It was reported that marked increase of TL-uptake in patients with acute myocardial infarction (AMI) corresponded to acute severe congestive heart failure. Here effect of TL-uptake on myocardial planar images was studied in 61 patients with AMI. In acute phase anterior, LAO 30 degrees and LAO 60 degrees myocardial images were collected. In 29 cases of 61 cases 3 to 6 hours delayed images could be collected. Each myocardial images was divided to 3 division and both images were compared. In 5 of 6 patients with marked increase of TL-uptake new defects were noted in anterior division of delayed images and in one case also in lateral division. In 7 patients of 12 patients with moderate increase of TL-uptake new defects were also noted in delayed images, i.e. 3 in anterior, 3 in inferior and one in apical division. It was concluded that over estimation of myocardial viability due to marked increase of TL-uptake was often noted in patients with AMI accompanying severe congestion. It became clear that delayed images were necessary to correctly estimate myocardial viability in such case.  相似文献   
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