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241.
Midlatency auditory evoked potentials and motor signs of wakefulness during anaesthesia with midazolam 总被引:1,自引:0,他引:1
Schwender D.; Daunderer M.; Schnatmann N.; Klasing S.; Finsterer U.; Peter K. 《British journal of anaesthesia》1997,79(1):53-58
We have studied midlatency auditory evoked potentials (MLAEP) and motor
signs of wakefulness during anaesthesia with midazolam in 10 patients
undergoing elective laparotomy under continuous extradural analgesia.
Anaesthesia was induced with midazolam 0.3 mg kg-1 and maintained with
midazolam 0.3-0.9 mg kg-1 h-1. Motor signs of wakefulness were documented
as spontaneous movements and movements after simple commands (open eyes or
move arms). MLAEP were recorded continuously awake, and during anaesthesia
until the end of anaesthesia. Latencies of the peaks V, Na, Pa, Nb and P1
(ms) and amplitudes of the peaks Na/Pa, Pa/Nb and Nb/P1 (microV) were
measured. Twenty-five movements were observed during anaesthesia; 15
movements in six patients were in response to commands. In two patients
supplementary isoflurane was given. Latencies of the MLAEP peaks Pa, Nb and
P1 increased slightly during anaesthesia. Amplitudes for Na/Pa, Pa/Nb and
Nb/P1 did not change significantly. The high incidence of motor signs of
wakefulness associated with preserved MLAEP indicated a high level of
cortical neural activity and none of the MLAEP variables predicted movement
during anaesthesia with midazolam.
相似文献
242.
Estimation of T and B lymphocytes was done in 50 patients of enteric fever, 50 duration matched non enteric fever patients and 50 normal healthy individuals. The difference in both early and late rosette forming T lymphocytes was found to be statistically significant in enteric versus non-enteric patients. Significant difference was also observed in enteric versus normal individuals in case of late rosette forming T lymphocytes. 相似文献
243.
Resulting from the knowledge that cyanobacteria (blue-green algae) are able to produce pharmacologically active substances the aqueous extracts from several cyanobacteria species and strains (Microcystis aeruginosa, Synechocystis aquatilis, Oscillatoria redekei, Anabaena flos-aque, Aphanizomenon flos-aquae, Oscillatoria rubescens, Oscillatoria tenuis) were tested for their immunomodulating activity. Extracts from Oscillatoria redekei 051, Oscillatoria tenuis 01 and Synechocystis aquatilis 428 caused an immunosuppression. They inhibited not only the incorporation of 3H-thymidine into mitogen stimulated lymphocytes but reduced also the number of plaque-forming cells of mice as shown by hemolysis-plaque-assay. Only extracts from Oscillatoria redekei 051 did not show any cytotoxic effects in lymphocyte cytotoxic test. This may be an evidence for a specific action on the proliferation of lymphocytes. 相似文献
244.
The concave and convex rib-vertebral angle (RVA) at levels T2–T12 was measured on AP radiographs of 19 patients with right convex idiopathic thoracic scoliosis and 10 patients with major thoracic right convex neuromuscular scoliosis. The difference between the angles on the concave and the convex sides, the RVAD, was calculated. The RVAs were also measured on radiographs from three animal groups in which spinal curves had been induced experimentally in a variety of ways. Group 1 comprised 16 rabbits that had been subjected to selective electrostimulation of the latissimus dorsi, the erector spinae and the intercostal muscles. Group 2 comprised four dead rabbits whose spines had been subjected to manual bending. Group 3 comprised eight rabbits that had undergone mechanical elongation of one rib. In both the idiopathic and the neuromuscular group, the convex RVA was smaller than the concave RVA between levels T2 and T8, with a maximal difference between T4 to T5. From T9 to T12 the concave RVA was smaller than the convex. The RVA in relation to the scoliotic segment, i.e. the apex level of the curve and the two neighbouring vertebrae above and below this level, showed similar results. With increasing Cobb angle the RVADs increased linearly with the greatest difference at the second vertebra above the apex. In the three experimental groups the pattern of the RVADs between T6 to T12 was basically similar to the findings of the clinical study. From the results of these clinical and experimental studies, it is concluded that the typical pattern of the RVAs on the concave and convex sides seems to be independent of the underlying cause of the spinal curvature. It is likely that the RVADs result from a passive mechanical adaptation of the ribs to the lateral curvature of the spine. 相似文献
245.
Characterization of nephropathy induced by immunization with high molecular weight dextran 总被引:1,自引:0,他引:1
Pasi A; Dendorfer U; Holthofer H; Nelson P; Tazzari S; Armelloni S; Fornasieri A; D'Amico G; Schlondorff D 《Nephrology, dialysis, transplantation》1997,12(9):1849-1855
Background. Injection of DEAE dextran into Lewis rats
can produce proteinuria and has been reported as a model of IgA
nephropathy. Methods. Cationic diethyl aminoethyl
(DEAE) dextran of molecular weight 500 KDa was injected into male Lewis
rats. After a pre-immunization period of 3 weeks, the animals were divided
into two groups: group 1 (n=14) received daily i.v. injections of 3.5 mg of
antigen, group 2 (n=14) was injected with 1.5 mg three times per week for a
total period of 6 weeks. I.v. treatment was initiated with gradually
increasing doses of DEAE dextran in both groups for 1 week, after which the
maintenance dose was reached. Results. We observed the
appearance of proteinuria in a nephrotic range after 5 weeks of i.v.
injections in group 1 (urinary excretion: 332±83 mg/24 h,
controls: 53±14 mg/24 h). In group 2, the proteinuria was almost
equal to protein excretion of healthy rats of the same weight
(67±20 mg/24 h). The serum and urine creatinine were normal. By
light microscopy of kidney biopsies, the presence of focal and segmental
proliferation of mesangial cells after 6 weeks of i.v. injections was
identified. Immunohistochemistry revealed no deposition of IgA, IgM, IgG,
or C3. Using anti-ED1 antibodies, there was no evidence of interstitial
infiltration of monocytes/macrophages after 6 weeks of i.v. injections.
Staining for proliferating cell nuclear antigen (PCNA) did not show the
presence of proliferating cells either in glomeruli or in the interstitium.
Staining with FITC-WGA lectin revealed focal and segmental loss of the
negative charge in the capillary wall. By electron microscopy there was
deposition of dextran in the basal membrane and segmental and focal damage
of the podocyte foot processes. As the chemokine RANTES may be involved in
glomerular injury, we examined the kidneys of proteinuric and
non-proteinuric rats for the presence of RANTES. By indirect
immunofluorescence only the proteinuric rats showed RANTES deposition in
mesangium. Conclusions. Injection of rats with DEAE
dextran leads to dose-dependent proteinuria without deposition of immune
complexes but with podocyte damage. This is associated with local
expression of the chemokine RANTES which may play a role in proteinuria of
glomerular disease. 相似文献
246.
This study has demonstrated the involvement of multiple forms of rat hepatic microsomal CoA ligases in the formation of 2-arylpropionyl-CoA thioesters. In the presence of (-)R-ibuprofen (0.1 microM-1 mM) two enzymic processes were observed, one of which exhibited enantiospecificity and apparent high affinity for the R enantiomer (Km 0.06 microM) whilst the second, a low-affinity component was non-enantiospecific. An equivalent high-affinity isoform catalysing R-flurbiprofen-CoA formation at concentrations less than 100 microM was not demonstrated. However, at higher substrate concentrations formation of both R- and S-flurbiprofenyl-CoA thioesters occurred. Marked inter-individual variation was observed in the formation of S-ibuprofen-CoA and S-flurbiprofen-CoA in the rats studied. 相似文献
247.
Results of intersphincteric resection of the rectum with direct coloanal anastomosis for rectal carcinoma. 总被引:13,自引:0,他引:13
J Braun K H Treutner G Winkeltau U Heidenreich M M Lerch V Schumpelick 《American journal of surgery》1992,163(4):407-412
Between 1977 and 1987, 519 patients underwent operation for rectal carcinoma. Sixty-three patients underwent intersphincteric resection with direct coloanal anastomosis (CAA), and 77 had an abdominoperineal resection (APR). Curative surgery was achieved in 57 and 65 patients, respectively. Both groups were comparable regarding age, stage of tumors, and localization of tumors. During the mean period of 6.7 years (range: 3 to 13.6 years), all patients were examined according to a predefined follow-up plan. From those patients with curative surgery, 11% presented with pelvic recurrence and 33% with distant metastases after coloanal anastomosis; the rates of recurrence and distant metastases after APR were 17% and 35%, respectively. The corrected 5-year survival rates were 62% following CAA and 53% following APR. Eighty-five percent of the patients with CAA reported good functional results regarding anal continence. Our study demonstrates that the intersphincteric resection with CAA is a valuable surgical technique for rectal carcinoma with the benefit of preservation of continence. It is suitable for neoplasms with high- and medium-grade differentiation (G1 to G2) and a localization that allows a minimum distal clearence of 3 cm. 相似文献
248.
F. Gebhard M. Marzinzig U. B. Brückner W. Hartel 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1997,382(5):243-251
In a prospective study, the systemic inflammatory consequences of surgery-induced lung tissue injury were evaluated using biochemical markers. The aim was to examine whether this type of injury produces a specific pattern of prostanoid plasma levels (prostacyclin, thromboxane, PGE2, PGF2α, and PGM). We, therefore, compared 18 patients (group 1) who underwent thoracotomy without injury to the lung with 26 patients (group 2) that had a resection of pulmonary tissue due to benign diseases. Group 2 patients clearly revealed increased plasma levels of C-reactive protein as well as of the granulocyte-specific PMN-elastase. In particular, there was a pronounced release of prostacyclin and its antagonist thromboxane A2 following lung tissue resection. In contrast to group 1 patients, lung tissue damage resulted in immediately elevated plasma levels of PGF2α and PGE2. When, however, taking into account the time course of PGM, the stable cleavage product of PGF2α, there was no hint of an altered pulmonary metabolic capacity. Presumably, this pattern of elevated prostanoid levels in group 2 is the result of the surgical damage to the lung tissue. Therefore, it can be suggested to be specific for that type of injury. Thus, the release of prostanoids following surgery-induced lung tissue damage may indicate the importance of these mediators, particularly in thoracic injuries associated with lung damage since those may lead to post-traumatic pulmonary dysfunction. These substances may also be useful in evaluating both the severity and the extent of lung tissue damage following major trauma. 相似文献
249.
Early detection of avascular necrosis of the femoral head following renal transplantation 总被引:3,自引:0,他引:3
B. Fink S. Degenhardt C. Paselk T. Schneider U. Mödder W. Rüther 《Archives of orthopaedic and trauma surgery》1997,116(3):151-156
This prospective study included 43 patients undergoing renal transplantations. Magnetic resonance imaging (MRI) and X-rays of the hip joints were produced 3 and 12 months after transplantation. In 6 hip joints of 4 patients (9.3%), we discovered femoral head necroses just 3 months after transplantation. Three of the hip joints affected were symptomatic and 3 painless. The MR images taken 12 months after transplantation revealed no additional femoral head necrosis. A core decompression was performed on 3 joints. In contrast to those with core decompression, the femoral heads without core decompression showed a progression of the necrosis in 2 of 3 cases. All 4 patients with femoral head necroses were younger than 50 years and exhibited a premature conversion of the haematopoietic marrow to fatty marrow in the area of the proximal femoral metaphysis. A similar premature conversion to fatty marrow was seen in 6 of the 22 (27.2%) patients younger than 50 years and without femoral head necroses. The doses in long-term steroid medication and the steroid doses during the rejection periods of the patients with femoral head necroses were not significantly higher than those for the patients with premature conversion to fatty marrow. The latter had also not received significantly higher doses than the patients whose MRI findings were inconspicuous. 相似文献
250.