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41.
The purpose of this study was to determine how changes in [HCO3-] alter the electrical properties of the retinal pigment epithelium (RPE). Experiments were conducted on the isolated chick retina-RPE-choroid preparation. The chamber holding the preparation allowed independent perfusion of the retinal and the choroidal surfaces. The light-evoked trans-tissue potential (TTP), the trans-epithelial potential (TEP), the trans-retinal potentials, and the intracellularly-recorded apical and basal membrane potentials were studied. Increasing the [HCO3-]0 in the choroidal bath from 25 to 40 mEq/1 led to an increase in the TTP and TEP. The same change in the retinal bath decreased the TTP because of a biphasic change of the RPE membrane potentials. There was also an increase in the amplitudes of the TEP, the c-wave and the slow PIII. The light-evoked subretinal K+ decrease was greater which is consistent with an increase in the photoreceptor light response. These observations indicated that the decrease of TTP resulted from a basal membrane hyperpolarization followed by an apical membrane depolarization induced by an increase in retinal [HCO3-]0. The relationship of these potential changes to the human bicarbonate responses is discussed.  相似文献   
42.
The effect of methanol extractives from tea leaves on hypercholesterolemia was examined in animal models. It was found that orally administered (-)-epicatechin gallate and (-)-epigallocatechin gallate from tea leaves lowered the serum cholesterol level in mice fed a high fat emulsion. Quantitation of tissue cholesterol and examination of liver tissues in mice fed a high cholesterol diet revealed that these constituents also significantly lowered the amount of cholesterol crystallization. These results support the reputed effectiveness of tea use in hypercholesterolemia.  相似文献   
43.
Objective To investigate the effect of recombinant human lactoferrin (rhLF) on cervical ripening using a rabbit model in which preterm labor was induced by bacterial endotoxin lipopolysaccharide (LPS). Study design Timed pregnant rabbits (New Zealand White, 3–4 kg, day 14) were randomly assigned to the following treatment groups: Group A, LPS + rhLF (n = 4); Group B, LPS (n = 4); and Group C, control (n = 4). Recombinant human lactoferrin (10 μg) was administrated to pregnant rabbits in Group A and not in Group B. Lipopolysaccharide (100 μg) was given to the rabbits in both groups for 3 days (days14–16). Drugs were administered as a vaginal suppository. On day 18, the rabbits were anesthetized with intramuscular ketamine hydrochloride (20 mg/kg) and diazepam (4 mg/kg). Both cervices of the rabbit uterus, which is bicorpus-bicolli, were taken out. One cervix was placed in 10% formalin solution for a histological study with standard hematoxylin-eosin staining. The other was used for an extension test to assess the grade of ripening. Extension was measured after a 5-mm length of cervical tissue was loaded with 5.8 g. Results The histological study showed remarkably loose and edematous connective tissue in Group B cervices. Cervical tissues in Group A was not different from those in Group C. Extension lengths were 2.2 ± 0.2 mm in Group A, 7.0 ± 2.7 mm in Group B, and 1.7 ± 0.3 mm in Group C. Conclusion These results suggest that rhLF inhibits cervical maturation induced by LPS in a rabbit model and may have a potential to prevent preterm delivery caused by cervical infection and ripening.  相似文献   
44.
Prognostic significance of Bcl-xL in human hepatocellular carcinoma   总被引:10,自引:0,他引:10  
BACKGROUND: Proliferation and apoptosis of liver cancer cells are closely related phenomena. We investigated the correlation between overexpression of Bcl-xL, an anti-apoptosis-related protein of the Bcl-2 family, and the clinical course of hepatocellular carcinoma (HCC). METHODS: Specimens from 7 HCC patients were used for Western blotting and immunoelectron microscopy tests. Samples from 33 HCC patients who had undergone hepatectomies were used for immunohistochemical staining. The degrees of expression of Bcl-xL and Ki-67, as an index of HCC mitosis severity, were each classified into 2 groups. RESULTS: With the use of Western blot analysis, enhanced immunoreactivity of Bcl-xL was found in cancerous specimens. Bcl-xL overexpression was found in cancer specimens in 21 of 33 patients (63.6%). The overall survival (P=.019) and disease-free survival (P=.030) rates of the group overexpressing Bcl-xL were definitely poorer. The Ki-67 higher labeling index LI > 10) group had a poorer survival rate (P=.016). There were significant correlations between Bcl-xL and overall survival and disease-free survival. Multivariate analyses revealed that Bcl-xL, tumor size, histologic portal invasion, and histologic metastatic foci were independent prognostic factors for overall survival and disease-free survival. CONCLUSIONS: These results showed Bcl-xL in HCC specimens, suggesting that Bcl-xL was a significant prognostic factor for disease progression in human HCC.  相似文献   
45.
46.
Aseptic meningitis and acute parotitis have been observed after mumps vaccination. Mumps outbreaks have been reported in Japan because of low vaccine coverage, and molecular differentiation is required to determine whether these cases are vaccine associated. RT-nested PCR was performed in the small hydrophobic gene region, and viruses were differentiated by restriction fragment length polymorphism assay. A total of 584 nucleotides were amplified. The PCR product of the Hoshino strain was cut into two fragments (313 and 271 nucleotides) by MfeI; that of the Torii strain was digested with EcoT22I, resulting in 332- and 252-nucleotide fragments. Both strains were genotype B and had an XbaI site, resulting in two fragments: 299 and 285 nucleotides. Current circulating wild types were cut only by XbaI or MfeI. However, the MfeI site of the wild types was different from that of the Hoshino strain, resulting in 451- and 133-nucleotide fragments. Using three restriction enzymes, two mumps vaccine strains were distinguished from wild types, and this separation was applied to the identification of vaccine-related adverse events.  相似文献   
47.
Sawada M  Watanabe S  Tsuda H  Kano T 《Anesthesia and analgesia》2002,94(6):1416-20, table of contents
Radiofrequency ablation (RFA) therapy using an active needle electrode inserted into liver tumors has been used clinically. To avoid hyperthermia, we investigated the relationship between the total output energy of the applied radiofrequency wave and changes in body temperature (BT) in patients receiving RFA. Fifteen patients undergoing RFA of liver tumors with general anesthesia were enrolled. The total output energy of radiofrequency waves was calculated from the power and duration of RFA. Changes in rectal (T(rect)) and tympanic temperatures were measured throughout the study. The mean number of liver tumors per patient was 1.7 +/- 1.3. The mean RFA time was 30.0 +/- 26.3 min. The mean total output energy was 125,935 +/- 114,506 J. The mean value of T(rect) increased from 36.3 degrees C +/- 0.5 degrees C to 37.0 degrees C +/- 1.0 degrees C (P < 0.01). A linear correlation was obtained between the total output energy and the changes in T(rect), indicating that T(rect) increased approximately by 1 degrees C for every 3000 J/kg of total output energy. The increase in BT during RFA of liver tumors under general anesthesia is predictable. Close observation of total output energy delivered and BT are required, and preparation of cooling measures is important, in RFA of liver tumors. IMPLICATIONS: The increase in body temperature (BT) is predictable during radiofrequency ablation (RFA) of liver tumors under general anesthesia. Close observation of total output energy delivered and BT are required, and preparation of cooling measures is important, in RFA of liver tumors.  相似文献   
48.
Although an ascending aortic thrombus is a rare finding, it may cause major embolic complications. We report a case of a 58-year-old male who suffered from cerebral and left renal infarctions due to emboli from a giant thrombus in the ascending aorta. The thrombus was demonstrated by computed tomography and transesophageal echocardiography. Ten days after the initiation of anticoagulation therapy, surgery was performed. After a median sternotomy was performed and cardiopulmonary bypass was initiated, the ascending aorta was replaced with a synthetic graft under hypothermic circulatory arrest and retrograde cerebral perfusion. The excised specimen revealed a 3.5×3.0×3.0-cm pedunculated thrombus. The patient's postoperative recovery was uneventful, and there was no recurrence of aortic thrombosis during one year of postoperative follow-up. The patient had no coagulation disorders, and the etiology of this giant thrombus remains unclear. We believe that initial treatment for an ascending aortic thrombus should be emergency surgery before it leads to major embolic events. However, the treatment strategy for a thrombus causing cerebral infarction is sometimes difficult to develop.  相似文献   
49.
We report the case of a 71-year-old male patient who underwent reoperation for bronchial stump fistula developing after left pneumonectomy for adenocarcinoma of the left lung (clinical stage IIB). After surgery, he developed persistent, severe cough and chest X-ray films taken on the 23rd postoperative day showed a drop in the air-fluid level in the left lung field, which, along with bronchoscopic findings, strongly suggested the bronchial stump fistula and subsequent reoperation was performed. Both superior pulmonary vein and main pulmonary artery were dissected again proximally in pericardium, and the left main bronchus was separated from the surrounding tissue. Bronchial stump was closed with a stapler as close to the carina as possible, and additional resection was performed. After reoperation, the patient had an uneventful course, and was discharged in the second postoperative week. Shorter length of bronchial stump may be the most important factor to prevent the bronchial stump fistula developing after pneumonectomy.  相似文献   
50.
We report the case of a ball-valve gastric tumor associated with anomalous junction of the pancreatico-biliary ductal system (AJPBDS) and a right-sided round ligament, misdiagnosed preoperatively as advanced gastric cancer with pancreatic head invasion. A 72-year-old woman presented with chest pain, but laboratory data showed only anemia. Gastroscopy revealed a bleeding polypoid gastric tumor in the anterior wall of the stomach, herniating into the duodenum (ball-valve syndrome), and a Bormann type-2 tumor in the posterior wall. Ultrasonography showed gallbladder stones, dilatation of the intrahepatic bile duct and pancreatic duct, and a left-sided gallbladder (attributed to a right-sided round ligament with anomalous branches of the portal veins). Laparotomy revealed that the gastric tumors were not advanced cancer invading the pancreatic head. Intraoperative cholangiography showed an AJPBDS, causing dilatation of the intrahepatic bile duct and pancreatic duct. We performed distal gastrectomy and cholecystectomy without biliary diversion. Microscopy revealed that the polypoid tumor was a hyperplastic polyp.  相似文献   
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