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131.
132.
The interaction between synovial cytokines and peripheral nerve function: a potential element in the development of radicular syndrome 总被引:1,自引:0,他引:1
P Wehling C H Evans K P Schulitz 《Zeitschrift für Orthop?die und ihre Grenzgebiete》1990,128(5):442-446
Cytokines of rabbit synovial origin were injected into 6 rats under the epineurium of the sciatic nerve. Five controls were injected with similar preparations lacking cytokines. After injection, rats were examined for a period of 7 days. For neurophysiological evaluation the tibial branch of the sciatic nerve was stimulated with supramaximal voltage impulses of constant duration. The responses were recorded at the dorsal root entry zone L1. F-wave latencies were recorded at the distal hind paw after stimulation of the tibial nerve. Filters were set at LF: 20 Hz, HF: 10 kHz. Synovial cytokines caused a significant decrease in amplitude and increase in latencies of the recorded nerve potentials. Our results indicate that interleukin-1, which is a major component of the synovial cytokine preparation, could play an important role in degenerative spine disease through a damaging effect on nerve function. This action would explain why radiculopathy and pain can develop without signs of nerve compression. The results are also relevant to patients suffering from osteoarthritis and rheumatoid arthritis. 相似文献
133.
The favored tautomeric and ionic structures were examined for the oxidative DNA damage adduct 8-hydroxy-2'-deoxyguanosine and its RNA analogue 8-hydroxyguanosine by 15N NMR spectroscopy. In addition, 15N chemical shifts and coupling constants from 13 different guanine nucleosides, including a wide variety of C8 substitutions (OH, SH, Br, OCH2C6H5, OCH3, SCH3, and SO2CH3), have been analyzed with respect to their tautomeric structures. A -98.5-Hz proton-nitrogen coupling constant observed for the N7 resonance of 8-hydroxyguanosine in dimethyl sulfoxide was evidence for 8-keto substitution, which is contrary to the structure implied by the generally used nomenclature. The pH dependence of 15N NMR spectra of 8-hydroxyguanosine in aqueous solution showed downfield shifts of the N1 and N7 resonances that were greater than 50 ppm, which indicated the conversion from a neutral 6,8-diketo to a 6-enolate-8-keto (pKa1 = 8.6) and finally to a 6,8-dienolate structure (pKa2 = 11.7). There was no evidence of an 8-enol substituent in the absence of ionization. It is proposed that the syn conformation of these oxidized bases in duplex DNA and RNA can be further stabilized by abnormal hydrogen bonding or mispairing that involves N7-H. The combined data show that 15N NMR is a sensitive probe to examine tautomerism of the guanine ring system. The analysis indicates that the change from a single to a double bond for the C8 substituent, and the accompanying removal of the normal double bond between N7 and C8 on the imidazole ring system, has no detectable effect on the tautomerism at the N1-O6 site of the pyrimidine ring system for both the 8-keto and 8-thio substitutions. In addition, large differences in electronegativity of the C8 substituents do not alter the N1-O6 tautomerism. 相似文献
134.
A. A. Paul A. E. Black J. Evans T. J. Cole R. G. Whitehead 《Journal of human nutrition and dietetics》1988,1(6):437-450
Longitudinal measurements of breastmilk intake in 48 Cambridge infants showed that intake reached a peak of 824 g/24 h in boys and 741 g/24 h in girls in the third and fourth months, respectively. Regression analysis demonstrated that, in the early months, the infants' weight accounted for a major part of the variance in breastmilk intake. Infants in non-manual social classes received more breastmilk and started solids later than those in manual groups. In the early months weight gain showed a relative increase compared to growth standards, but later infancy was characterized by a progressive deceleration in weight and length gain. Adiposity, as measured by triceps skinfold thickness differed most markedly from growth charts and was only equivalent to the tenth standard centile at all ages. The lower skinfold thickness measurements are considered to be more appropriate to breastfed infants in general. 相似文献
135.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
136.
137.
Posterior tibial neurothlipsis in the retromalleolar space, secondary to internal fixation of a prior ankle fracture, is presented in the following report. The possibility of a tarsal tunnel syndrome cannot be ruled out. No apparent similar reference is made in the medical literature concerning the above etiology of posterior tibial compression/neurothlipsis/tarsal tunnel syndrome. Electrodiagnosis with sensory nerve conduction velocities is reviewed for more accurate diagnosis of tarsal tunnel syndrome. 相似文献
138.
A modified formulation of inhaled salbutamol and a new inhaler device were studied in a group of 11 moderate-to-severe asthmatic patients. Changes in airway calibre (FEV1, Vmax30) were measured before and after inhalation of the new formulation, and compared with changes following inhalation of conventional salbutamol. A standard Rotahaler was used as a reference for the new inhaler. The study was conducted as a two-part randomized, double-blind cross-over trial. We found a significantly greater bronchodilatation of the larger airways using the modified drug in the Rotahaler. The new inhaler did not show any superiority over the Rotahaler, contrary to expectations from in vitro work. A slightly shorter model may better reflect the in vitro results. The study has implications for inhalation therapy in general. 相似文献
139.
The validity and use of psychosocial assessments in occupational therapy are ongoing concerns (Moyer, 1984) and were the focus of this study. Fifty African patients with schizophrenia and 10 nondysfunctional African volunteers took an an assessment battery that included the Schroeder, Block, Campbell Adult Psychiatric Sensory Integration Evaluation (SBC) (Schroeder, Block, Trottier, & Stowell, 1978), a daily activity, work, and leisure activity interview based on the Model of Human Occupation (Kielhofner, 1985), and a culture-specific test of functional performance. Data on subjects' psychiatric histories and demographics were collected. Rationale for the assessments used, methods for devising the functional assessment, methods and procedures for data collection, and analysis are presented. A stronger relationship was found to exist between subjects' performances on the SBC and the functional activity test than between interviews based on the Model of Human Occupation and the functional activity test, both for patients and for the whole sample. All assessments were found to differentiate between patients and nonpatients, although the SBC was the best discriminator. Among psychiatric history variables, the strongest relationships were between measures of seriousness of illness and both the SBC and functional activity assessment. The most effective way to measure performance dysfunction and seriousness of illness in persons with schizophrenia was to measure the underlying sensorimotor impairment or to use a culture-specific test of functional performance. 相似文献
140.