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81.
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to evaluate the chlorhexidine gluconate (CHG) susceptibility in both planktonic cells and biofilm of...  相似文献   
82.
Background: The complications of the gastric pouch in gastric bypass surgery are well known. Since the first report of this surgery 30 years ago, new technical aspects that make it safer and more effective have been implemented. Methods: As a modification of gastric bypass, the authors have performed 305 vertical banded gastroplasty-gastric bypass procedures. Two groups of patients underwent the procedure: Group I (n = 206) without a limb of jejunum interposed between the gastric pouch and the excluded stomach, and Group II (n = 99) with a limb of jejunum interposed between the pouch and the stomach. The results regarding excess weight loss and complications of the gastric pouch during the first year after surgery were compared. Results: Age, sex, initial weight, body mass index, and percentage of ideal weight were similar in both groups. Excess weight loss was also similar. The complications in Group I were 1 leak, 3 left subphrenic abscesses, 2 erosive gastritis with bleeding, 1 stenosis of the gastrojejunostomy, 1 perforated ulcer, and 4 marginal ulcers with bleeding. Two patients in Group II developed bleeding from the staple-line. Conclusions: These preliminary data suggest that complications of the gastric pouch can be reduced by interposing a limb of jejunum between the pouch and the excluded stomach. This is an early experience; long-term results are pending.  相似文献   
83.
A study was conducted to determine the prevalence of substandard visual acuity in a sample of the diverse communities of the United States Air Force. In addition, mobility readiness (visual), ocular disease, time since last visual examination, and adherence to ocular requirements per AFR 160-43 were assessed. Comprehensive eye examinations were performed in the Optometry Clinic on 207 randomly chosen members scheduled by Squadron Schedulers using random computer lists of personnel generated by Military Personnel Flight. Of the 207 individuals, 112 (54%) had not had a professional eye examination in the last 2 years, 51 (24%) were not mobility ready, 6 (3%) had inadequate visual acuity per AFR 160-43, and 4 (1.9%) had ocular disease. The study reinforces the concept that comprehensive, periodic ocular examinations should be performed by an optometrist or ophthalmologist on all active duty members to ensure that they see properly to perform assigned duties, that members on mobility have required optical materials to be deployment ready, and that members who develop ocular disease are identified in a timely manner.  相似文献   
84.
Summary Radiotracer techniques capable of measuring norepinephrine clearance and spillover rate into plasma were used to test the hypothesis that the antihypertensive effects of propranolol and atenolol in conscious spontaneously hypertensive rats are associated with an inhibition of norepinephrine release from postganglionic sympathetic neurons. The 10%–15% fall in mean arterial pressure produced over 4 h by propranolol (1, 3.3 and 10 mg/kg, s. c.) and atenolol (1, 3.3 and 10 mg/kg, s. c.) was not dose-related, and only the largest dose of propranolol caused a significant bradycardia. Each dose of atenolol significantly lowered heart rate. The decrease in blood pressure caused by propranolol and atenolol was not related to the decrease in heart rate. Both propranolol and atenolol inhibited norepinephrine clearance by 12% to 16%. The 1 mg/kg doses of propranolol and atenolol significantly suppressed norepinephrine spillover rate by 21 % and 32%, respectively, at 4 h postinjection. As the dose of propranolol was increased, the inhibition of norepinephrine spillover was reversed as plasma epinephrine concentration rose by 125%. The suppression of norepinephrine spillover rate caused by atenolol was more persistent but did diminish after the 10 mg/kg dose, when plasma epinephrine concentration was elevated by 55%. Both drugs suppressed plasma renin concentration, but the inhibition of norepinephrine spillover rate by propranolol and atenolol was not related to the fall in plasma renin concentration. By comparison, treatment with the adrenergic neuron blocking agent bretylium (5, 10, 20 and 40 mg/kg, s. c.) elicited a dose-related vasodepression with no change in heart rate or plasma renin concentration. The 10 mg/kg dose of bretylium inhibited norepinephrine spillover rate by 40%, but increasing the dose did not produce a further suppression of norepinephrine spillover rate. Bretylium caused a dose-related elevation of plasma epinephrine concentration (354% increase at 40 mg/kg). In a separate study, propranolol (10 mg/kg) and bretylium (40 mg/kg) significantly increased epinephrine spillover rate by 85% and 118%, respectively. Based on these data, we conclude that the -adrenoceptor antagonists lower blood pressure by inhibiting norepinephrine release from postganglionic sympathetic neurons. Send offprint requests to T. K. Keeton at the above address  相似文献   
85.
86.
From January 1988 to September 1989, seven patients (4 girls and 3 boys, aged 3–12 years) with haemorrhagic fever with renal syndrome (HFRS) were hospitalised at the University Children's Hospital in Belgrade. In four patients the disease appeared as a family outbreak, the others were sporadic cases. In six patients the clinical presentation was suggestive of HFRS, as they had fever with headache, myalgia, sore throat and gastrointestinal illness followed by renal abnormalities. However, severe haemorrhagic syndrome with petechia, haematoma, haematemesis and melaena was present in one patient only. Renal disease presented as nephritic syndrome and/or acute renal failure. Five patients recovered after 2–3 weeks without sequellae, one patient had decreased renal function 17 months after the start of the disease and the remaining patient died. In six patients the diagnosis of HFRS was confirmed serologically by a significant rise in antibody titres against hantaviruses, while in the patient with the fatal and fulminant course of the disease, the diagnosis was established on the basis of epidemiological and autopsy findings. We suggest that children living in endemic areas who develop an ill-defined, febrile and gastrointestinal disease with renal dysfunction should be evaluated for HFRS.  相似文献   
87.
Intravenous administration of antibothropic antivenom (BAv) neutralises the systemic effects, but does not efficiently reverse the local symptoms elicited by the Bothrops jararaca venom (BjV). The mechanisms involved in this poor protection have not been clarified. In this work, intravital microscopy studies were carried out to determine the efficacy of different schedules of BAv treatment on local effects evoked by topical application of BjV in the microcirculatory network of the internal spermatic fascia of Wistar rats. Results demonstrated that BAv administration 15 min before, simultaneously with, or 15 min after BjV application did not totally reverse the local symptoms, represented by disturbances of coagulation, development of haemorrhage lesions, vascular permeability increase and increment on leukocyte-endothelium interactions. This lack of effectiveness neither reflects an inadequate amount of specific antibodies in the antivenom against toxins responsible for local effects nor an insufficient dose of circulating BAv during the assays. Administration of fluorescein isothiocyanate (FITC) labelled-BAv showed the dynamics of distribution of the antivenom in the microcirculatory network. Images obtained from prior and simultaneously treated animals showed that the antivenom remains at luminal side of vessels before venom application, and the latency time to antivenom leakage is coincidental to that for local effects evoked by the venom. In addition, images from posterior treatment demonstrated that the intense alterations in the microcirculatory network impair antivenom distribution at the site of injection. Together, our data show that the lack of effectiveness of antivenom therapy is due to impaired and delayed venom and antivenom interaction at the site of injury.  相似文献   
88.
PURPOSE AND EXPERIMENTAL DESIGN: The stem cell factor/KIT receptor loop may represent a novel target for molecular-based therapies of Ewing tumor. We analyzed the in vitro impact of KIT blockade by imatinib in Ewing tumor cell lines. RESULTS: KIT expression was detected in 4 of 4 Ewing tumor cell lines and in 49 of 110 patient samples (44.5%) by immunohistochemistry and/or Western blot analysis. KIT expression was stronger in Ewing tumors showing EWS-FLI1 nontype 1 fusions. Despite absence of c-kit mutations, constitutive and ligand-inducible phosphorylation of KIT was found in all tumor cell lines, indicating an active receptor. Treatment with KIT tyrosine kinase inhibitor imatinib (0.5-20 micro M) induced down-regulation of KIT phosphorylation and dose response inhibition of cell proliferation (IC(50), 12-15 micro M). However, imatinib administered alone at doses close to IC(50) for growth inhibition (10 micro M) did not induce a significant increase in apoptosis. We then analyzed if blockade of KIT loop through imatinib (10 micro M) was able to increase the antitumor in vitro effect of doxorubicin (DXR) and vincristine (VCR), drugs usually used in Ewing tumor treatment. Addition of imatinib decreased in 15-20 and 15-36% of the proliferative rate of Ewing tumor cells exposed to DXR and VCR, respectively, and increased in 15 and 30% of the apoptotic rate of Ewing tumor cells exposed to the same drugs. CONCLUSIONS: Inhibition of Ewing tumor cell proliferation by imatinib is mediated through blockade of KIT receptor signaling. Inhibition of KIT increases sensitivity of these cells to DXR and VCR. This study supports a potential role for imatinib in the treatment of Ewing tumor.  相似文献   
89.
90.
Medial prefrontal cortex (MPFC) transection enhances social interaction in an open arena test. Social interaction enhances dopaminergic activity in the nucleus accumbens (NAC). In the present set of experiments, microdialysis probes were implanted in the NAC, and glutamate, gamma-aminobutyric acid (GABA) and dopamine (DA) were measured during electrical stimulation of the MPFC, after coronal transection caudal to the MPFC and after a systemic injection of amphetamine in transected rats. Electrical stimulation of the MPFC caused a transient enhancement of glutamate release in the NAC, no change in GABA levels and a long lasting increase in DA levels. Medial prefrontal transection did not change basal glutamate or GABA levels in the NAC, but increased basal DA levels. Amphetamine administration decreased GABA levels in medial prefrontal transected rats, had no effect on glutamate and increased DA levels more than in controls. The experiments suggest that glutamatergic activity in the accumbens decreases dopamine release. Medial prefrontal transection reduces glutamatergic tone and enhances dopamine release, which probably decreases GABAergic activity in the NAC. Presumably, GABA inhibition in the NAC enhances social interaction.  相似文献   
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