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71.
We report a case of Takayasu's disease with severe renovascular hypertension in a girl from Eritrea. In the "burn-out" phase after the erythrocyte sedimentation rate had normalized, reconstructive vascular surgery was performed as further progression of the disease seemed unlikely. However, probably due to her growth, the graft rotated and a second operation was successfully performed.  相似文献   
72.
Spike triggered averaging was used to record local circuit connections between pairs of CA1 pyramidal neurons in isolated slices of rat hippocampus. Of 795 pairs of neurons tested, six were connected. These epsps were only partially blocked by 2-amino-5-phosphonovalerate (AP-5), which decreased the amplitude and half width of the epsp, but did not affect the early rising phase. In contrast, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) blocked all phases of the epsp and combinations of AP-5 and CNQX blocked the epsp almost entirely. These results indicate that these epsps were mediated by both N-methyl-d-aspartate (NMDA) and non-NMDA excitatory amino acid receptors. Moreover, they exhibited a voltage relation typical of neuronal responses to NMDA, increasing in amplitude and duration as the postsynaptic cell was depolarized. These epsps were brief (10 - 90% rise time < 5 ms, width at half amplitude < 20 ms), indicating a proximal location. Increasing presynaptic firing rate (1 - 4 spikes/s) reduced average epsp amplitude by almost 50%. When epsps were evoked by pairs of spikes (interval 3 - 25 ms), a large response to the first spike precluded a large response to the second. No evidence for selective enhancement of the NMDA receptor component by paired spike activation was found. It is concluded that a significant NMDA receptor mediated input to CA1 is provided by local circuit CA1 - CA1 connections and that these synapses can be demonstrated under control conditions.  相似文献   
73.
Observer variation in the interpretation of lower limb venograms.   总被引:3,自引:0,他引:3  
After agreeing on diagnostic criteria and after a pilot study, two experienced radiologists twice independently reviewed 40 lower limb venograms performed by a standard technique in patients suspected or known to have venous thrombosis. The observers reviewed 20 examinations at a time, their analysis requiring separate identification of 11 major veins. At each site observers stated whether thrombus was "absent," "doubtful," "presumed," or "definite," or declared "no opinion possible." They then rediscussed criteria of diagnosis and, using the same experimental design, examined another 40 venograms. To correct for agreement expected by chance, data were analyzed by using the kappa statistic. In general, levels of agreement were higher than those reported for many other clinical and radiologic investigations, probably because of refinement of criteria after the pilot study. Nonetheless, observers disagreed about the probable presence or absence of thrombus at some site in the limb in about 10% of examinations. Observer variation should be considered when venography is used as a reference standard to evaluate other methods of diagnosing thrombi.  相似文献   
74.
Acupuncture analgesia: an experimental investigation.   总被引:3,自引:0,他引:3  
A study was designed to establish whether acupuncture has any analgesic properties beyond those of suggestion. In three one-hour experimental sessions the increases in detection thresholds and tolerances for thermal pain at six body locations on 12 subjects were compared. A control session (without needles) was followed by one session in which electrically stimulated needles were inserted in accord with Chinese practice, and another in which the needles were inserted to avoid all recognised acupuncture "points." Acupuncture was significantly more effective than suggestion in raising overall body pain thresholds but just below significance for tolerances. A significant disproportionate effect on the epigastrium, predicted by the choice of acupuncture points, was found for tolerances but not thresholds.  相似文献   
75.
1. Ninety-one families containing 140 children under 4 years of age at enrolment were studied. At 1-monthly intervals, the children were weighed and measured and qualitative information about feeding habits was obtained. Weighed dietary surveys for periods of 5 d were made at approximately 8 months, 3 years, and 5 years of age; there were forty-six failures in 260 surveys attempted. 2. At the four specified ages, mean energy intakes were 3-75, 5-03, 5-82 and 6-75 MJ (896, 1203, 1392 and 1613 kcal)/d respectively. At 8 months, milk products provided on average, 43% of the total energy intake, and commerical baby foods provided 17%. These values decreased to 21 and 2% respectively at 20 months and there was little further change therafter. 3. Average intake of energy and of most nutrients met recommended intakes (Department of Health and Social Security, 1969). Iron intakes were marginal, and vitamin D intakes were low. 4. The energy intake of boys was significantly higher than that of the girls at 3 years of age, but the boys were not significantly heavier. The energy intake of children from "manual-worker" families was higher than that from "non-manual" families. Similarly, the energy intake of children from larger families was higher than that of children from smaller families. 5. Energy intakes were correlated with body-weights and with rates of gain in weight. Irrespective of body-weight, "big eaters" at 20 months tended to be "big eaters" at 3 years also.  相似文献   
76.
PURPOSE: Asparaginase therapy is an important component in the treatment of children with acute lymphoblastic leukemia. Polyethylene glycol-conjugated asparaginase (PEG-ASNase) has significant pharmacological advantages over native Escherichia coli asparaginase. We investigated the pharmacokinetics of PEG-ASNase, presence of antibodies to PEG-ASNase, and concentrations of asparagine in serum and cerebrospinal fluid (CSF) in combination chemotherapy for relapsed pediatric acute lymphoblastic leukemia. EXPERIMENTAL DESIGN: Twenty-eight pediatric patients with relapsed medullary (n = 16) and extramedullary (n = 11) acute lymphoblastic leukemia were enrolled at three pediatric institutions and had at least two serum and CSF samples obtained for analysis. Patients received induction therapy (including PEG-ASNase 2500 IU/m2 intramuscularly weekly on days 2, 9, 16, and 23) and intensification therapy (including PEG-ASNase 2500 IU/m2 intramuscularly once on day 7). Serum samples were obtained weekly during induction and intensification. CSF samples were obtained during therapeutic lumbar punctures during induction and intensification. RESULTS: Weekly PEG-ASNase therapy resulted in PEG-ASNase activity of >0.1 IU/ml in 91-100% of patients throughout induction. During intensification, PEG-ASNase on day 7 resulted in PEG-ASNase activity >0.1 IU/ml in 94% and 80% of patients on days 14 and 21, respectively. Serum and CSF asparagine depletion was observed and maintained during induction and intensification in the majority of samples. PEG-ASNase antibody was observed in only 3 patients. CONCLUSIONS: Intensive PEG-ASNase therapy in the treatment of relapsed acute lymphoblastic leukemia reliably results in high-level serum PEG-ASNase activity, and asparagine depletion in serum and CSF is usually achieved. Incorporation of intensive PEG-ASNase in future trials for recurrent acute lymphoblastic leukemia is warranted.  相似文献   
77.
Fibronectin (a glycoprotein which modulates inflammation) may decrease mortality in systemic infection. Children with meningococcal disease (MCD) may have low fibronectin levels. We aimed to compare plasma fibronectin levels in children with MCD and controls, correlate fibronectin levels with interleukin-6 (IL-6), shock and death, and assess fibronectin as an aid to early diagnosis in MCD. Samples were taken on admission from 99 children with MCD and 49 controls. Plasma fibronectin was measured using a turbidimetric immunoassay. Plasma fibronectin was significantly lower in MCD compared to controls (57 μg/ml vs 105 μg/ml; P < 0.005). Children who died had significantly lower levels than survivors (29 μg/ml vs 62 μg/ml; P = 0.01). Fibronectin levels were negatively correlated with IL-6 levels. Fibronectin was a poor predictor of MCD. Conclusion Plasma fibronectin levels are decreased in children with MCD, especially in shock and death. This decrease is associated with high IL-6 levels. Fibronectin could be a novel therapy in severe MCD. Received: 6 June 1996 / Accepted: 16 October 1996  相似文献   
78.
A segment of the population has a defect in the metabolism of tryptophan that causes a lowered concentration of serotonin in the central nervous system and indicates a predisposition towards chronic alcoholism. The metabolic defect in tryptophan metabolism is in the pathway between tryptophan and 5-hydroxyindoleacetic acid (5-HIAA) but not in the other pathways of tryptophan metabolism. A test using HPLC with amperometric detection was developed to detect the presence of an impaired serotonin metabolic pathway and therefore indicate a predisposition towards chronic alcoholism. The test used a ratio between 5-HIAA and two metabolites (indoleacetic acid and anthranilic acid) from the other pathways of tryptophan metabolism to indicate the presence or absence of an impaired serotonin metabolic pathway while correcting for variations in the concentration of urine.  相似文献   
79.
Computed tomographic detection of nonbeta pancreatic islet cell tumors   总被引:6,自引:0,他引:6  
  相似文献   
80.
A 22-year-old man presented with traumatic aortic transtion associated with rupture of the right atrium and underwent urgent median sternotomy to repair the right atrium. A T-shaped extended left anterior thoracotomy was performed, and ruptured descending thoracic aorta was repaired under total bypass. A Y-shaped connector was inserted in the arterial catheter to allow cannulation of both ascending aorta and femoral arteries. A 4-cm long Hemoshield graft was used to repair the aortic transection. The patient made a full recovery and was discharged 13 days after the accident.  相似文献   
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