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21.
Background: Pancreatic carcinoma is one of the most lethal cancers. Because pancreatic carcinoma is still very difficult to diagnose in its early stage, many of these patients will be considered unsuitable for surgery. If a cytological diagnosis is obtained at initial endoscopic retrograde cholangiopancreatography (ERCP), suitable treatment will be initiated without delay. Methods: To increase the number of exfoliated cells from the pancreatic duct, we devised a new technique, pancreatic duct lavage fluid (PDLF), following bronchoalveolar lavage fluid. The present paper reports the effectiveness of cytological examination using PDLF in the diagnosis of pancreatic carcinoma. We examined 18 pancreatic carcinoma cases. After the endoscopic retrograde pancreatography (ERP), PDLF was collected from a double‐lumen catheter inserted into the main pancreatic duct. Saline injected from the lumen for the injection, and PDLF was aspirated from the other lumen for the guidewire at the same time. The cytological examination was performed using PDLF. Results: Exfoliated cells were more frequently found in PDLF from all patients. In 15 cases (83%), cytological examination of PDLF revealed positive cytological results as the diagnosis of pancreatic carcinoma. Conclusion: Cytological examination using PDLF has a high sensitivity for detection of pancreatic carcinoma. The new examination, PDLF, is simple, safe and effective, so we expect PDLF to become widely popular.  相似文献   
22.
Our new finding of de novo synthesis and secretion of C3 by both murine peritoneal macrophages and polymorphonuclear leukocytes (PMN) was confirmed by the incorporation of [35S]methionine into C3 molecules and their complete inhibition by cycloheximide. The methods of secretion of C3 from these two types of cells were compared by examining the C3 contents in their culture supernatants. Completely different modes of secretion were observed, i.e. although macrophages synthesize and secrete C3 constitutively, PMN has a mechanism to store the already synthesized C3 in the cell and secrete it in response to stimuli. Protein kinase C (PKC) activators, e.g. 12-O-tetradecanoyl-phorbol 13-acetate, dioctanoyl glycerol, and mezerein, as well as calcium ionophore A23187 stimulate the secretion of C3 from PMN. These results suggest the involvement of PKC and the calmodulin pathway. A very sensitive method for measuring C3 activity was developed which enabled us to show for the first time that C3 secreted by PMN had opsonizing activity and that particles cultured with PMN were phagocytosed effectively.  相似文献   
23.
The effects of nilvadipine on the peripheral circulation in the lower extremities using a duplex system of two-dimensional colour and pulse Doppler ultrasonography were studied in 32 patients with type 2 diabetes mellitus and mild essential hypertension. The patients (19 men and 13 women) were randomly divided into treatment and control groups. The anatomical cross-sectional area and blood flow index of the dorsal pedis artery were determined by colour and pulse Doppler ultrasonography before and 60 min after administration of 4 mg nilvadipine or placebo. Pulse rate and blood pressure were measured simultaneously. There were no significant changes in pulse rate or blood pressure after administration of either drug. Both cross-sectional areas (from 4.3 +/- 0.4 to 5.2 +/- 0.5 mm2, p < 0.05) and blood flow index (from 40.3 +/- 4.3 to 58.8 +/- 9.0, p < 0.05) were significantly increased in the treatment group, whereas there were no significant changes in either measurement in the control group. The findings showed that a single administration of nilvadipine increases blood flow in the dorsal pedis arteries of diabetic patients.  相似文献   
24.
Hypoglycemia has been observed in several species before death from endotoxemia. Although several studies have emphasized the importance of maintaining brain glucose at normal concentration during endotoxemia, the effect of glucose infusion on cerebral glucose metabolism has not been studied. Accordingly, the effects of glucose infusion on interstitial glucose and lactate concentrations in the cerebral cortex during endotoxemia were studied in 22 Wistar rats. Cerebral glucose and lactate were measured at 30-min intervals for 4 h using microdialysis. Animals were divided into four groups: 1) saline-infused control (n = 5); 2) saline-infused endotoxemia (n = 7); 3) glucose-infused control (n = 5); and 4) glucose-infused endotoxemia (n = 5). In groups 2 and 4, endotoxemia was induced by intravenous injection with E. coli lipopolysaccharide B (5 mg.100 g-1). One hour after endotoxin administration, saline or 50% glucose was infused at a flow rate of 0.5 ml.100 g-1.h-1 for 3 h. Endotoxin induced a significant increase (P less than 0.05) in blood glucose in the saline-infused rats, which survived for 4 h (n = 5), from 91.6 +/- 15.4 mg.100 ml-1 at baseline to 136.3 +/- 23.3 mg.100 ml-1 (149%) at 1 h, followed by a gradual decrease (to 63% of the basal concentration at 4 h). Similar changes were observed in brain glucose (14.9 +/- 1.9 mg.100 ml-1 baseline, 175% of baseline at 2 h, and 57% of baseline at 4 h).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
25.
The relationship between the perfusion flow rate and cerebral oxygen consumption during deep hypothermic cardiopulmonary bypass at 20 degrees C was investigated in dogs. In 10 dogs the perfusion flow rate was decreased in steps from 100 to 60, 30, and 15 ml/kg/min every 30 minutes. Although cerebral blood flow decreased as perfusion flow rate decreased, the ratio of cerebral blood flow to the perfusion flow rate increased significantly (p less than 0.05) at a perfusion flow rate of 15 ml/kg/min compared to that at a perfusion flow rate of 100 or 60 ml/kg/min. The arterial-sagittal sinus blood oxygen content difference increased as perfusion flow rate decreased. Consequently, cerebral oxygen consumption did not vary significantly at perfusion flow rates of 100 (0.48 +/- 0.10), 60 (0.43 +/- 0.14), and 30 ml/kg/min (0.44 +/- 0.12 ml/100 gm/min), and it decreased significantly to 0.31 +/- 0.22 ml/100 gm/min at a perfusion flow rate of 15 ml/kg/min. In five dogs the perfusion flow rate was decreased in one step from 100 to 15 ml/kg/min, and after 60 minutes' perfusion at a perfusion flow rate of 15 ml/kg/min, the perfusion flow rate was returned to 100 ml/kg/min. Cerebral oxygen consumption decreased significantly during 60 minutes' perfusion at a perfusion flow rate of 15 ml/kg/min and did not return to its initial value after the perfusion flow rate was returned to 100 ml/kg/min. These data indicate that the optimal perfusion flow rate for the brain during deep hypothermic cardiopulmonary bypass at 20 degrees C appears to be 30 ml/kg/min, with a possible oxygen debt in the brain resulting in anaerobic metabolism if the perfusion flow rate is kept at 15 ml/kg/min or less.  相似文献   
26.
Introduction A few epidemiologic studies have comprehensively attempted to identify risk factors for low bone mineral density (BMD) in elderly Asian women. The purpose of this study was to identify demographic, lifestyle, and biochemical factors correlated with BMD in elderly Japanese women 69 years of age and over.Methods The study design was cross-sectional. The subjects were 583 ambulatory women aged 69 years and over, and their average age was 74.3 (SD 4.4) years. Predictor variables were age, reproductive history, anthropometric indices, grip strength, calcium intake, lifestyle information, and serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D (1,25(OH)2D), osteocalcin (OC), and undercarboxylated osteocalcin (ucOC) values. The outcome variable was forearm BMD measured with a DTX-200 osteometer.Results Simple linear regression analyses showed that BMD was significantly positively associated with body height, weight, body mass index, grip strength, serum albumin concentration, and “housework,” and negatively associated with age, years since menopause, age at menarche, number of children, serum 1,25(OH)2D concentration, serum OC concentration, and ucOC concentration. The stepwise multiple regression analysis showed that weight (β=0.00316, SE=0.00028, R2=0.180), age (β=−0.00321, SE=0.00050, R2=0.108), log-transformed serum OC (β=−0.0445, SE=0.0064, R2=0.053), log-transformed serum 1,25(OH)2D (β=−0.0401, SE=0.0074, R2=0.050), “farmwork” (β=0.00904, SE=0.00426, R2=0.005), and serum 25(OH)D concentration (β=0.000281, SE=0.000120, R2=0.003) were significantly associated with BMD.Conclusion It was concluded that body weight is a major predictor of forearm BMD among the factors measured in this study in independent Japanese women 69 years of age and over and that serum 1,25(OH)2D concentration may be associated with cortical BMD. Maintenance of body weight is very important for maintaining BMD in this population, unless a large weight aggravates obesity-related diseases. A follow-up study is needed to confirm these findings.  相似文献   
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28.
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important causative microorganisms for nosocomial infections. Recently, the incidence of isolation of MRSA has been increasing every year in Japan and is, notably, much more frequently found in inpatients than in outpatients. Therefore, we have done epidemiological studies of MRSA isolated from medical staff, inpatients, and the hospital environment in one ward of our hospital. Thereafter, we examined the antibiotic susceptibility (ABPC, DMPPC, CET, CMZ, IPM, GM, MINO, OFLX, EM, CLDM, VCM), phage typing, and coagulase typing of these MRSA. MRSA were isolated more frequently from anterior nares of inpatients than from doctors and nurses. MRSA were isolated more frequently from the environment near carriers of MRSA. Coagulase type II and phage type N.T. (not typable) were the dominant types of MRSA in our hospital (69% and 61%). MRSA strains were resistant to most antibiotics with a few exceptions (VCM, IPM, CMZ, CET). The high isolation frequency of MRSA in our hospital seems to suggest that inpatients who are carrying MRSA spread MRSA throughout the hospital environment and that the anterior nares of inpatients are the major MRSA harbor.  相似文献   
29.
Seven human gastric cancer xenografts with different concentrations of EGF receptor were established in nude mice. The expression of EGF receptor in the tumors was demonstrated by Western blotting with anti-EGF receptor antibody, binding assay with 125I-EGF and immunohistochemistry with anti-EGF receptor antibody. Western blotting revealed EGF receptor doublet bands at molecular masses of 150 KDa and 170 KDa in all of the samples. The concentration of 125I-EGF binding activity in the tumors ranged from 36.0 to 11,000 fmol/mg protein, with a mean of 345 fmol/mg protein. EGF receptor was also demonstrated immunohistochemically on the apical border of the glands and the cell membrane of the tumor cells. There seemed to be a close correlation between the concentration of 125I-EGF binding activity and the doubling time of these tumors in nude mice (gamma = -0.68). However, no definite correlation was observed between EGF ligand binding and histological features of intestinal type or diffuse type. The expression of EGF receptor appears to facilitate the growth of human gastric cancer xenografts in nude mice.  相似文献   
30.
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