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21.
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   
22.
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   
23.
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   
24.
25.
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   
26.
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   
27.
Perioperative tumor localization for laparoscopic colorectal surgery   总被引:4,自引:3,他引:1  
Background: Because of the inability to palpate colonic tumors during laparoscopy, their location must be precisely identified before resection is undertaken. Method: A retrospective study was performed of 58 patients in order to be able to describe our methods of tumor localization for laparoscopic colorectal operations and to review their effectiveness. Results: In all patients, the entire colon was examined preoperatively by colonoscopy. In one patient, preoperative colonoscopic localization was inaccurate. In 31 patients, tumors were easily detectable at surgery. In five patients with the tumor in the right colon, even though the lesion was not detectable at surgery, right colectomy was performed without marking because preoperative colonoscopy reliably identified the lesion adjacent to the ileocecal valve. Twenty-two patients required some type of procedure to localize the tumor. The procedures and their problems were as follows: preoperative tattoo (five)—tattoo not visualized (one); intraoperative colonoscopy alone (six), combined with intraoperative tattoo (four) or clip (three)—poor operative exposure due to bowel distension (nine), hard to see the clip (three), dislodged clip (two), inadequate resection margin (one); intraoperative proctoscopy alone (two), combined with laparoscopic stitch (two)—no problems. In no patient was tumor present at a resection line and in no patient was the wrong segment resected. Conclusions: Reliable preoperative identification of the tumor adjacent to the ileocecal valve can permit right colectomy without marking. Lesions in the upper rectum can be approached via intraoperative proctoscopy ± suture placement. If the surgeon anticipates intraoperative localization may be difficult, lesions other than rectal or cecal ones should probably be marked by preoperative tattooing. Further studies regarding the technique of tattooing are warranted. Received: 18 July 1996/Accepted: 10 March 1997  相似文献   
28.
To determine the anomeric preference of uptake of D-glucose and of D-galactose by rat lenses, we crystallized alpha-, beta-D-[U-14C]glucose (720 microCi/mmol) and alpha-, beta-D-[U-14C]galactose (180 microCi/mmol) by our method and incubated them separately with rat lenses for 1 min, because of the short half-life of mutarotation of alpha-D-glucose (9.6 min) and of alpha-D-galactose (4.6 min) in HEPES medium at 30 degrees C. During aerobic incubation of rat lenses in HEPES medium containing radioactive alpha or beta anomer of D-glucose, there was no significant difference in the rate of uptake between alpha and beta anomers of D-glucose by rat lenses. However, 1.59 times greater incorporation of alpha-D-galactose was observed over that of beta-D-galactose under the same conditions.  相似文献   
29.
Fourteen strains of Eikenella corrodens isolated from human oral cavity were studied to determine corroding characteristics. Nine out of the 14 strains produced corroding colonies under anaerobic culture condition. One of them produced corrosion even in an aerobic culture. No morphological differences in surface structures were observed between corroding and non-corroding strains of E. corrodens by transmission electron microscopy. The morphology of corroding colonies of E. corrodens was then examined by scanning electron microscopy. The surface of the corroding-colony center was smoothly convex. A boundary line was clear between the smooth center and the surrounding corrosion region. Double or triple frill-like structures surrounded the center portion with small convexities. Spreading bacterial masses were observed in the outer portion of the colony. Morphological observations of the corroding colony edge indicated that a surface translocation termed "twitching motility" or "gliding motility" occurs in the outer portion and plays a role in its colonization of periodontal regions.  相似文献   
30.
Key words  intractable pain - celiac plexus neurolysis - ultrasonography  相似文献   
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