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1.
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   
2.
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   
3.
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   
4.
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   
5.
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   
6.
Relapse remains the most common cause of treatment failure after hematopoietic cell transplantation for acute myeloid leukemia. Inability to achieve hematologic complete remission has been a barrier to transplant for patients with refractory disease. We describe six children with refractory myeloid disease undergoing transplant in chemotherapy‐induced aplasia, as a strategy to facilitate curative therapy in refractory patients. Clofarabine‐ or high‐dose cytarabine‐based chemotherapy regimens were used to achieve marrow aplasia, followed by reduced‐intensity conditioning and allogeneic transplant before hematologic recovery. Long‐term disease control was achieved in five, with one transplant‐related mortality, suggesting the feasibility of this approach.  相似文献   
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Previous findings from this laboratory suggest a role for milk-borne PRL in the development of the inhibitory neuroendocrine controls over PRL secretion. Thus, rats that consumed milk deficient in PRL on days 2-5 postpartum show reduced concentrations and turnover of DA in the median eminence and elevated serum levels of PRL at 30-35 days of age. The present experiments were undertaken to investigate whether these consequences of neonatal PRL deficiency persist beyond puberty, and whether alterations in pituitary responsiveness to hypothalamic hormones may be involved. Lactating rats received sc injections of either saline or the dopamine (DA) agonist bromocriptine (125 micrograms/rat.day) on each of days 2-5 postpartum, a treatment that reduces the amount of PRL in milk without abolishing lactation. Blood samples were obtained from male and female offspring at various postnatal ages, and PRL concentrations were determined by RIA. Serum PRL concentrations in offspring from both groups were low until after weaning, but the female offspring of bromocriptine-treated mothers showed significantly elevated serum PRL between days 30 and 90 postpartum. Male offspring of bromocriptine-treated mothers also had transiently increased serum PRL levels, which returned to control levels by day 40. The turnover rate of DA in the median eminence, calculated from the rate of decline after synthesis inhibition, was reduced on day 35 in neonatally PRL-deficient offspring, as shown previously. However, no differences in DA turnover between the two groups were apparent on day 60, indicating a recovery of normal dopaminergic activity. Anterior pituitary cells of 100-day-old control and neonatally PRL-deficient animals were dispersed, cultured for 3 days, and then exposed to either TRH, to stimulate PRL release, or to the DA agonist bromocriptine, which inhibits PRL release. Pituitary cells of neonatally PRL-deficient offspring were almost completely unresponsive to bromocriptine with regard to suppression of PRL release and cytoplasmic PRL mRNA levels. In contrast, pituitary cells of neonatal PRL-deficient offspring were somewhat more responsive to TRH in stimulating PRL release and increasing the levels of PRL mRNA. These results suggest that a brief period of PRL deficiency during the neonatal period may result in long-lasting alterations in control of PRL secretion. The resultant hyperprolactinemia may be initiated by a reduction in the release of DA from the hyothalamus, perhaps reflecting a role for milk-derived PRL in the functional development of this neurosecretory system, and maintained in part by a reduction in pituitary responsiveness to DA.  相似文献   
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