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11.
Power spectral analysis of the electroencephalographic and hemodynamic correlates of propofol anesthesia in the rat: Intravenous infusion 总被引:2,自引:0,他引:2
Peter P. C. Tan Ming-Hwang Shyr Chen-Hsein Yang Terry B. J. Kuo Wynn H. T. Pan Samuel H. H. Chan 《Neuroscience letters》1993,160(2):205-208
Based on the tail-flick response to noxious thermal stimuli, we determined in the present study that effective antinociception could be achieved in adult male Sprague-Dawley rats 15 min after intravenous infusion of propofol at 60 mg/kg/h. Simultaneous power spectral analysis of the electroencephalographic (EEG) and systemic arterial pressure signals further revealed a concomitant depression of the activity of all EEG frequency bands (δ, θ, , β), alongside hypotension, negative inotropic and chronotropic actions, and attenuated baroreceptor reflex and vasomotor activity. These effects were congruent with a plasma concentration of propofol in the arterial blood of 1.70 ± 0.13 μg/ml, as determined by high-performance liquid chromatography. 相似文献
12.
Comparison of different PCR approaches for characterization of Burkholderia (Pseudomonas) cepacia isolates. 总被引:1,自引:2,他引:1
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P Y Liu Z Y Shi Y J Lau B S Hu J M Shyr W S Tsai Y H Lin C Y Tseng 《Journal of clinical microbiology》1995,33(12):3304-3307
In this study, we evaluated three PCR methods for epidemiological typing of Burkholderia (Pseudomonas) cepacia--PCR-ribotyping, arbitrarily primed PCR (AP-PCR) and enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR)--and compared them with pulsed-field gel electrophoresis. The analysis was performed with 31 isolates of B. cepacia, comprising 23 epidemiologically unrelated isolates and 8 isolates collected from the same patient during two episodes of bacteremia. Pulsed-field gel electrophoresis, ERIC-PCR, and AP-PCR identified 23 distinct types among the 23 unrelated isolates, while PCR-ribotyping only identified 12 strain types, even after AluI digestion of the amplification products. Among the eight isolates collected from the same patient, all typing techniques revealed two clones of strains. The day-to-day reproducibilities of PCR-ribotyping and ERIC-PCR were good, while greater day-to-day variations were noted in the fingerprints obtained by AP-PCR. We conclude that all three PCR techniques are useful for rapid epidemiological typing of B. cepacia, but ERIC-PCR seems to be more reproducible and discriminative. 相似文献
13.
Helicobacter pylori genotypes, host factors, and gastric mucosal histopathology in peptic ulcer disease 总被引:10,自引:0,他引:10
Tham KT Peek RM Atherton JC Cover TL Perez-Perez GI Shyr Y Blaser MJ 《Human pathology》2001,32(3):264-273
From 183 patients undergoing upper gastrointestinal endoscopy, we used antral and corpus gastric biopsies for bacterial culture and histopathologic examination, blood samples to detect immunoglobulin G antibodies against Helicobacter pylori, and H pylori genomic DNA to analyze cytotoxin-associated gene A (cagA) and vacuolating cytotoxin (vacA) genotypes. As expected, among H pylori biopsy-positive patients, those with duodenal ulcer (DU) (n = 34) had significantly more severe chronic and acute inflammation (P <.001) and epithelial degeneration (P =.004) in the gastric antrum than in the gastric corpus. Each of those 3 parameters and H pylori density were significantly higher in the antrum of patients with DU than in patients with gastric ulcer (GU) or no ulcer. Colonization with vacA s1/cagA-positive strains of H pylori was associated with inflammation and epithelial degeneration in gastric mucosa and increased risk for peptic ulcer disease (PUD), whereas colonization with vacA s2m2/cagA-negative strains was associated with mild gastric histopathology and was not associated with any significant risk for PUD. The predominant H pylori strains in African Americans were vacA s1bm1/cagA-positive, whereas all genotypes were well represented in non-Hispanic-Caucasians. By multivariate analysis, H pylori colonization was significantly associated with DU (Adjusted odds ratio [AdjOR] = 3.2 [1.4-7.2]) and nonsteroidal anti-inflammatory drugs (NSAID) use was inversely associated (AdjOR = 0.3 [0.2-0.7]). NSAID use (AdjOR = 4.3 [1.02-18.5]) and African-American ethnicity (AdjOR = 10.9 [2.6-50]) were significantly associated with GU. Smoking and age were not significantly associated with either DU or GU. These data indicate that DU is associated with an antral-dominant gastritis, and H pylori genotype and NSAID use independently contribute to the pathogenesis of PUD. HUM PATHOL 32:264-273. This is a US Government work. There are no restrictions on its use. 相似文献
14.
BackgroundThere are no reports of performing mesopancreas dissections in robotic pancreaticoduodenectomy. This study evaluated the feasibility and justification for mesopancreas level 3 dissection in robotic pancreaticoduodenectomy.MethodsSurgical outcomes after robotic pancreaticoduodenectomy and open pancreaticoduodenectomy were evaluated and compared.ResultsThere were 289 robotic pancreaticoduodenectomy and 162 open pancreaticoduodenectomy patients included in the study. Postoperative diarrhea occurred in 34.5% of mesopancreas level 3 dissection cases and was higher than in levels 2 and 1 dissection cases, P < .001. Blood loss in the robotic pancreaticoduodenectomy group was higher for mesopancreas level 3 dissection, with a median loss of 263 mL (P = .015). The rate of R0 resection with margin >1 mm was higher for mesopancreas level 3 dissection (93.8%) than for level 2 dissection (72.2%) (P < .001). The lymph node yield was higher for mesopancreas level 3 dissection in robotic pancreaticoduodenectomy; the median lymph node yield was 21 for level 3, 18 for level 2, and 14 for level 1 (P < .001). Compared with mesopancreas levels 1 and 2 dissections in the robotic pancreaticoduodenectomy groups, level 3 dissection did not show increased surgical mortality or postoperative complications, including postoperative pancreatic fistula, delayed gastric emptying, postpancreatectomy hemorrhage, chyle leakage, bile leakage, or wound infection. Compared with open pancreaticoduodenectomy, mesopancreas level 3 dissection in robotic pancreaticoduodenectomy had less blood loss, no delayed gastric emptying, and lower chyle leakage.ConclusionMesopancreas level 3 dissection in robotic pancreaticoduodenectomy is feasible without compromising surgical safety. Therefore, robotic pancreaticoduodenectomy can be recommended as a safe alternative to open pancreaticoduodenectomy for mesopancreas level 3 dissection. 相似文献
15.
We report a girl who developed severe and fatal hyperkalemia following rapid and massive blood transfusion during surgery. She was 7-year-old, 20-kg in weight, and received wide resection of the femoral bone with custom prosthesis implant because of malignant femoral osteosarcoma. During the procedure, bleeding was active and profuse and amounted to about 3,000 mL in 4 h, eventuating in shock. Despite rapid transfusion with 15 units of packed red blood cells (RBC) still she remained hypotensive and hypovolemic. When we switched to give her whole blood, actually 100 mL having been given, widening of QRS complex followed immediately by cardiac arrest developed. Cardiopulmonary resuscitation although started at once was unsuccessful. At this juncture, arterial blood gas analysis showed acidosis and severe hyperkalemia (10.3 mmol/L), possibly resulting from transfusion of blood of older storage. The case reminded us once again the importance and necessity of the use of potassium-low blood component (fresh, saline-washed RBCs) in case of massive and rapid blood transfusion especially in pediatric patients with hypovolemia and low cardiac output. 相似文献
16.
The palpation and enucleation of occult insulinomas (less than 15 mm) can be a difficult surgical problem even with good arteriographic localization. In the authors' limited experience, confirmation of arteriographic findings by pancreatic venous sampling provided little additional localizing information. However, if arteriography is negative or equivocal, venous sampling can indicate the segment of pancreas to be "blindly" resected if the adenoma is not palpable. Venous sampling may be misleading in polyendocrine syndromes because of the frequency of multiple adenomas and variable hormone production. 相似文献
17.
Prospective Study of Gastric Outlet Obstruction in Unresectable Periampullary Adenocarcinoma 总被引:2,自引:0,他引:2
Controversy persists regarding the role of prophylactic gastrojejunostomy in patients with unresectable periampullary adenocarcinoma.
In review of the retrospective series, presence of gastric outlet obstruction (GOO) has been claimed to be a bad prognostic
sign. This prospective study aimed to clarify the necessity of routine prophylactic gastrojejunostomy in patients with unresectable
periampullary adenocarcinoma. The incidence and prognostic significance of GOO were also evaluated. Sixty-six patients with
unresectable periampullary adenocarcinoma were enrolled. They were divided into 2 groups to receive either a single biliary
bypass or a double bypass (concomitant gastric and biliary bypasses) if they had GOO. The single bypass group was followed
up to assess the incidence of GOO and subsequent need of a gastric bypass. Prognostic factors were evaluated by univariate
and multivariate analyses. Forty-four (67%) of the overall 66 patients presented with GOO at the time of diagnosis. There
was no statistical difference regarding the morbidity and mortality between the 2 groups, except longer (7 days) hospital
stay in the double bypass group. Seven (31.8%) of the 22 patients in the single bypass group subsequently developed GOO an
average of 6.2 ± 1.0 months after their initial biliary bypass. By univariate analysis, significant prognostic factors for
unresectable periampullary adenocarcinoma were: GOO (p= 0.0379), pancreatic head origin (p= 0.0146 by univariate analysis), and distant metastasis (p < 0.0001). After multivariate analysis, only pancreatic head origin and distant metastasis remained significant independent
factors of poor prognosis. In conclusion, gastrojejunostomy should be performed prophylactically in addition to a biliary
bypass in patients with unresectable periampullary adenocarcinoma. The presence of GOO is not an independent factor of poor
prognosis, but a reflection of the aggressive biologic behavior of pancreatic head adenocarcinoma. 相似文献
18.
19.
0 引言 1 992 - 0 5~ 1 999- 0 5我科收治慢性硬膜下血肿 (CS-DH) 1 6 8例 ,其中 1 6 4例经颅骨钻孔冲洗引流术治疗 ,4例保守治疗 ,结果 1 6 5例治愈 ,3例死亡 .结论 :CSDH的诊断主要依靠 CT检查 ,手术简单 ,防止并发症可改善预后 .1 临床资料 男 1 6 3例 ,女 5例 ,年龄 32~ 79岁 ,平均 5 4岁 .有明确的外伤史 1 4 5例 (86 .3% ) ,原因不明 2 3例(1 3.7% ) ,病程 3wk~ 6 a.头昏、头痛、呕吐 1 1 6例 ,肢体运动障碍 6 8例 ,智力及精神障碍 46例 ,语言障碍 1 0例 ,感觉障碍2 1例 ,排尿障碍 5例 ,癫痫 3例 ,视乳头水肿 92例 ,锥体… 相似文献
20.