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921.
M Ghielli WA Verstrepen S Dauwe EJ Nouwen ME De Broe 《Canadian Metallurgical Quarterly》1997,5(1):69-81
This study investigated the behaviour exhibited by 17 neuropathic pain patients (almost half of whom had documented neurological injury) with diffuse pain and extraterritorial sensory, sudomotor and vasomotor abnormalities, under the influence of intravenous administration of saline-controlled sodium amytal (SA), a medium action barbiturate. After SA (but not after normal saline) infusion, there was a dramatic and selective reduction of allodynia (touch-evoked pain) in all patients displaying this phenomenon, while pin prick and cold hypo- or hyperalgesia, as well as algometric pressure thresholds of the symptomatic limb (as a measurement of deep pain) were minimally changed in most patients. Spontaneous subjective pain was reduced substantially but not totally. The patients were able (once allodynia was eliminated) to recognize a deep-seated pain of which they were unaware before, evoked by firm but gentle palpation of the limb. Sympathetic blocks and A-fibre ischemic blocks in several patients and spinal stimulation in one patient produced effects identical to those observed during SA administration. The deep pain component was maintained despite elimination of allodynia even under stages of sleep induced by SA, at which time the patients would withdraw only the symptomatic limb upon firm but gentle palpation. We argue that neuropathic pain patients have two separate pain components, a cutaneous one (touch-evoked pain or allodynia) mediated by large fibres as a product of central sensitization, and a deep pain component mediated via nociceptors, which can be easily discriminated during systemic administration of SA. 相似文献
922.
The role of xenobiotic metabolizing enzymes in arylamine toxicity and carcinogenesis: functional and localization studies 总被引:1,自引:0,他引:1
KF Windmill RA McKinnon X Zhu A Gaedigk DM Grant ME McManus 《Canadian Metallurgical Quarterly》1997,376(1-2):153-160
Familial apolipoprotein C-II (apo C-II) deficiency is an autosomal recessive genetic disorder characterized by fasting hypertriglyceridemia and accumulation of chylomicrons in the plasma. To elucidate the genetic defect, the apo C-II gene of a neonatal Japanese patient (C-IITokyo) was analyzed. Nucleotide sequence analysis showed a G+1 to C transversion at the donor splice site of intron 2 (INT2 G+1 to C). Restriction fragment length polymorphism analyses of the patient's family members with Hph I showed that the patient was homozygous and the parents were heterozygous for the INT2 G+1 to C mutation. Although consanguinity could not be demonstrated, haplotype analysis of the C-II gene revealed the identity of the patient's alleles on the mutation, suggesting that the parents had a common Japanese ancestor. Sequence analysis of the patient's cDNA isolated from peripheral blood lymphocytes revealed that the INT2 G+1 to C mutation causes skipping of exon 2, which encodes the initiation codon, and results in deficiency of apo C-II proteins. The outstanding feature of our patient was that he showed severe hypertriglyceridemia beginning in the neonatal period, a feature not reported in a case of apo C-II deficiency (C-IIHamburg) with the same mutation as our patient. A previous report of another case of apo C-II deficiency (C-IIToronto) suggested that the apo E4 isoform is associated with higher levels of plasma triglycerides in subjects heterozygous for the apo C-II mutation. Determination of the apo E isoform of our patient revealed that apo E4 was coinherited with the INT2 G+1 to C mutation, whereas the apo E isoform has been reported to be E2/3 in C-IIHamburg. We speculate that apo E4/4 aggravated the hypertriglyceridemia in our patient with apo C-II deficiency. 相似文献
923.
924.
925.
We examined the attenuation and integration of spontaneous excitatory postsynaptic potentials (sEPSPs) in the dendrites of presumed motoneurons (MNs) of organotypic rat spinal cord cultures. Simultaneous whole cell recordings in current-clamp mode were made from either the soma and a dendrite or from two dendrites. Direct comparison of the two voltage recordings revealed that the membrane potentials at the two recording sites followed each other very closely except for the fast-rising phases of the EPSPs. The dendritic recording represented a low-pass filtered version of the somatic recording and vice versa. A computer-assisted method was developed to fit the sEPSPs with a generalized alpha-function for measuring their amplitudes and rise times (10-90%). The mean EPSP peak attenuation between the two recording electrodes was determined by a maximum likelihood analysis that extracted populations of similar amplitude ratios from the fitted events at each electrode. For each pair of recordings, the amplitude attenuation ratio for EPSP traveling from dendrite to soma was larger than that traveling from soma to dendrite. The linear relation between mean ln attenuation and distance between recording electrodes was used to map 1/e attenuations into units of distance (micron). For EPSPs with typical time course traveling from the somatic to the dendritic recording electrode, the mean 1/e attenuation corresponded to 714 micron for EPSPs traveling in the opposite direction, the mean 1/e attenuation corresponded to 263 micron. As predicted from cable analysis, fast EPSPs attenuated more in both the somatofugal and somatopetal direction than did slow EPSPs. For EPSPs with rise times shorter than approximately 2.0 ms, the attenuation factor increased steeply. Compartmental computer modeling of the experiments with biocytin-filled and reconstructed MNs that used passive membrane properties revealed amplitude attenuation ratios of the EPSP traveling in both the somatofugal and somatopetal direction that were comparable to those observed in real experiments. The modeling of a barrage of sEPSPs further confirmed that the somato-dendritic compartments of a MN are virtually isopotential except for the fast-rising phase of EPSPs. Large, transient differences in membrane potential are locally confined to the site of EPSP generation. Comparing the modeling results with the experiments suggests that the observed attenuation ratios are adequately explained by passive membrane properties alone. 相似文献
926.
Lyme disease is well known for affecting the myocardium in the form of carditis and dilated cardiomyopathy. Pericardial effusion associated with Lyme disease has not been described as yet. This article demonstrates a case of a female patient, 54 years of age, with Borrelia burgdorferi infection and associated pericardial effusion. Recurrent pericardiocenteses as well as conventional treatment of the condition were without success. Diagnosis of Borrelia infection and subsequent treatment with ceftriaxone led to permanent restitution of the pericardial effusion. 相似文献
927.
928.
The mechanisms underlying the increased risk of wheezing in early childhood following acute bronchiolitis in infancy remain unclear. Previous studies have reported significant abnormalities in infant respiratory function after clinical recovery from bronchiolitis, but are difficult to interpret because of the frequent omission of a concurrent comparison group. Respiratory function was compared within pairs of previously healthy full-term caucasian infants admitted with a first episode of acute bronchiolitis to an inner London hospital, and age- and sex-matched control infants without prior wheezing, asthma, or lower respiratory illness who were recruited from local general practices. Respiratory function was measured in 29 control and 29 asymptomatic index infants, with measurements in the latter done at a median interval of 36 wk (range: 16 to 49 wk) after admission, when 16 (55%) had experienced subsequent wheezing. Index infants tended to be autumn-born and of shorter gestation than control infants, to have younger mothers, and to have been exposed to tobacco smoke. There were no statistically significant differences in plethysmographic FRC, initial inspiratory airway resistance (Raw), or respiratory system compliance (mean [index minus control] within-pair difference [95% confidence interval]: -11 ml [-29, 7 ml]; -0.2 kPa/L/s [-0.7, 0.4 kPa/L/s]; -8 ml/kPa [-21, 4 ml/kPa], respectively), but respiratory rate and time to peak tidal flow as a proportion of total expiratory time (tPTEF:tE) were significantly diminished in index as compared with control infants (-4.0 breaths/min [-7.6, -0.4 breaths/min], versus -0.035 [-0.066, -0.005], respectively). These findings suggest a better prognosis for infant lung function after acute bronchiolitis than reported previously. Longitudinal studies are needed to clarify whether subclinical alterations in airway function precede acute bronchiolitis. 相似文献
929.
Two cyclic, C2-symmetric HIV-1 protease inhibitors, one sulfamide and one urea derivative, both comprising phenyl ether groups in the P1/P1' positions, were cocrystallized with HIV-1 protease, and the crystal structures were determined to 2.0 A resolution. The structure of the urea 2 showed a conformation similar to that reported for the related urea 3 by Lam et al., while the sulfamide 1 adopted an unanticipated conformation in which the P1' and P2' side chains were transposed. 相似文献
930.
ME Lowe 《Canadian Metallurgical Quarterly》1997,127(4):549-557
Extracorporeal photochemotherapy (ExP) is a well-tolerated new form of chemoimmunotherapy, which is considered to be effective for cutaneous T-cell lymphoma (CTCL) and the treatment of choice for Sézary syndrome. Improvements have also been seen in patients with non-erythrodermic mycosis fungoides (MF) in the early stages, even when tumour cells are not detectable in the peripheral blood. In this study, we used ExP as a monotherapy in seven patients who had early stage (Ib) MF, and who were no longer responsive to or had contraindications for other therapies. We observed a clinical improvement in the disease after 12 months of treatment: one patient showed a complete response, five a partial response, and one remained stable. In each patient we compared skin biopsies of large plaque lesions before and after the treatment. We undertook a histological evaluation of the infiltrate. The lymphoid cell proliferation and death rates were quantified using the following parameters; lymphoid cell density (LCD), Ki67 + lymphoid cell nuclei percentage (Ki67 + Lcn percentage), and apoptotic index (AI). Significant decreases in the lymphoid cell infiltrate and in cell proliferation, and a significant increase in AI were observed after therapy. The mean LCD decreased from 187 +/- 33 to 34 +/- 17.7, Ki67 + Lcn mean percentage decreased from 16.9 +/- 3.9 to 4.9 +/- 2.4, and the AI mean value increased from 0.05 +/- 0.03 to 2.41 +/- 1.54. Our results suggest a role for apoptosis in the improvement of the skin lesions and are in line with some reports on the mode of action of ExP. Although the way in which ExP works needs to be clarified further, it does seem to stimulate a CD8+ cell-mediated anticlonotypic activity against circulating pathogenic clones. Furthermore, a release of tumour necrosis factor alpha (TNF-alpha) by circulating monocytes has been demonstrated after ExP. Both are known to induce cell death by apoptosis. 相似文献