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951.
OBJECTIVE: To determine possible differences in gestational diabetes mellitus (GDM) between aboriginal and non-aboriginal people in the Saskatoon Health District. RESEARCH DESIGN AND METHODS: This was a prospective survey of all women admitted for childbirth to the Saskatoon Royal University Hospital between January and July 1998. We compared prevalence rates, risk factors, and outcomes of GDM between aboriginal and non-aboriginal women. RESULTS: Information was obtained from 2,006 women, of whom 252 aboriginal and 1,360 non-aboriginal subjects had been tested for GDM. The overall rates of GDM were 3.5% for women in the general population and 11.5% for aboriginal women. For those living within the Saskatoon Health District, GDM rates were 3.7 and 6.4%, respectively. Multivariate analysis demonstrated that aboriginal ethnicity, most notably when combined with obesity, was an independent predictor for GDM. Pregravid BMI > or = 27 kg/m(2) and maternal age > or = 33 years were the most important risk factors for GDM in aboriginal women, whereas previous GDM, family history of diabetes, and maternal age > or = 38 years were the strongest predictors for GDM in non-aboriginal women. CONCLUSIONS: There may be fundamental differences in GDM between aboriginal and non-aboriginal people. Because GDM contributes to an increased risk for type 2 diabetes in aboriginal women and their offspring, the impact of prevention and optimal treatment of GDM on the type 2 diabetes epidemic in susceptible populations are important areas for further investigation. 相似文献
952.
ATP responses in human C nociceptors 总被引:4,自引:0,他引:4
Hilliges M Weidner C Schmelz M Schmidt R Ørstavik K Torebjörk E Handwerker H 《Pain》2002,98(1-2):59-68
Microelectrode recordings of impulse activity in nociceptive C fibres were performed in cutaneous fascicles of the peroneal nerve at the knee level in healthy human subjects. Mechano-heat responsive C units (CMH), mechano-insensitive but heat-responsive (CH) as well as mechano-insensitive and heat-insensitive C units (CM(i)H(i)) were identified. A subgroup of the mechano-insensitive units was readily activated by histamine. We studied the responsiveness of these nociceptor classes to injection of 20 microl 5 mM adenosintriphosphate (ATP) using saline injections as control. Because of mechanical distension during injection, which typically activates mechano-responsive C fibres, interest was focused on responsiveness to ATP after withdrawal of the injection needle. Post-injection responses were observed in 17/27 (63%) mechano-responsive units and in 14/22 (64%) mechano-insensitive units. Excitation by ATP occurred in 9/11 CH units and in 5/11 CM(i)H(i) units. ATP responsive units were found both within the histamine-responsive and the histamine-insensitive group of mechano-insensitive fibres. ATP responses appeared with a delay of 0-180 s after completion of injection; responses were most pronounced during the first 1-3 min of activation, and irregular ongoing activity was observed for up to 10 or even 20 min. ATP responses were dose-dependent, concentrations lower than 5 mM gave weaker responses. No heat or mechanical sensitisation was observed in any of the major fibre classes. In conclusion, we have shown that ATP injections at high concentrations activate C-nociceptors in healthy human skin, without preference for mechano-responsive or mechano-insensitive units. ATP did not sensitise human C fibres for mechanical or heat stimuli. We discuss how various mechanisms might contribute to the observed responses to ATP. 相似文献
953.
Ditting T Linz P Hilgers KF Jung O Geiger H Veelken R 《Basic research in cardiology》2003,98(6):388-400
Abstract.
Recent studies suggest a role of ion channels of the
DEG/ENaC family for mechanosensation in different species and in
baroreceptor reex control in rats. We tested the hypothesis
that ENaC within the cardiac sensory network are mandatory for
mechanosensation. Experiments were performed in male
Sprague-Dawley rats, isolated nodose ganglion cells with cardiac
afferents and isolated vagus nerves.Epicardial delivery of the amiloride analogue benzamil
intended to specifically inhibit ENaC presumably located on
cardiac sensory afferents indeed blunted the mechanosensitive
(i. e., sympathoinhibition by intravenous volume loading [–32%
and –42% in treated groups vs. –67% in controls; n = 7 each; p
< 0.05]) as well as—though to a lesser extent—the
5-HT3-mediated chemosensitive cardiorenal
reex in vivo in a dose-dependent manner. Using patch clamp
technique, however, it turned out that neither amiloride nor
benzamil inuenced mechanically induced currents in ganglion
nodosum cells in vitro, stimulated by hypoosmotic stress. The
unspecific stretch activated ion channel blocker gadolinium
completely abolished mechanically induced currents, indicating
respective cells were mechanosensitive. In isolated vagus nerves
benzamil impaired action potentials obtained by electrical
stimulation (C-spike amplitude [–33%]; latency [+12%]; n = 8; p
< 0.05).Our ndings at least cast doubt on ENaC exclusively
playing a specific role as mechanotransducers within the cardiac
sensory network. Other ion channels might be involved.
Furthermore the observed ndings in vivo could also be due to
unspecific disturbance of afferent signal conduction. 相似文献
954.
955.
956.
957.
Borràs E Martin R Judkowski V Shukaliak J Zhao Y Rubio-Godoy V Valmori D Wilson D Simon R Houghten R Pinilla C 《Journal of immunological methods》2002,267(1):79-97
Combinatorial libraries and in particular positional scanning synthetic combinatorial libraries (PS-SCL) allow the study of T cell specificity. This is a systematic and unbiased approach that does not require any previous knowledge about the clones to be studied, neither their specificity nor they major histocompatibility complex (MHC) restriction. Two different types of T cell clone ligands can be identified: (1) peptides that do not necessarily correspond to proteins described in the databases, and (2) peptides that are fragments of natural proteins. In this paper, relevant examples of the application of PS-SCL and the deconvolution strategies followed to identify T cell epitopes for clones of known and unknown specificity will be reviewed. Also, important issues like the immunogenicity of such T cell ligands will be discussed. 相似文献
958.
Giger R Szalay-Quinodoz I Haenggeli A Dulguerov P 《American journal of otolaryngology》2002,23(6):390-393
Cervical spinal synovial and/or ganglion cysts can occur at various periarticular sites and should be considered in the differential diagnosis of intraspinal-extradural or paraspinal masses of the cervical spine. The first report of a ganglion cyst of the cervical anterior longitudinal ligament presenting as a retropharyngeal mass, is presented. The histopathology, etiology, and clinical aspects of synovial and ganglion cysts of the cervical spine are briefly reviewed. 相似文献
959.
We describe an alternative, endoscopical technique for the surgical removal of a rare chondrosarcoma on the nasal septum. The technique requires a resection of the whole tumour within margins in healthy osteocartilaginous nasal septum under endoscopic guidance and includes bilateral middle turbinectomy and ethmoidectomy. We present the case of a 57-year-old woman with a well-differentiated chondrosarcoma (Grade I) of the nasal septum. Endoscopical surgery resulted without any cosmetic deformity problems, and the functional result was favourable. No recurrence was evidenced after a follow-up of 3 years. The main advantages of this technique are the excellent functional and cosmetic results without any surgical reconstructive techniques. This approach may provide a minimally invasive method to remove well-differentiated, low-grade (Grade I) and size limited malignant cartilaginous tumours of the nasal septum. 相似文献
960.
Jones TM Hargrove O Lancaster J Fenton J Shenoy A Roland NJ 《The Journal of laryngology and otology》2002,116(4):275-279
The waiting times incurred during the management of 75 consecutive head and neck oncology patients attending for post-treatment follow-up were reviewed. Data were gleaned from general practitioner (GP) referral letters, patient case-notes as well as radiology and histology reports. The mean time for GP referral to ENT was 5.1 weeks. From ENT to endoscopy was 3.1 weeks, to histology 3.5 weeks, to computed tomography (CT) scan 5.6 weeks, to magnetic resonance scan (MR) 4.1 weeks, to primary radiotherapy 10.3 weeks and to surgery 5.5 weeks. The mean symptom duration prior to referral was 4.9 months. Our results compare unfavourably with the standards recommended by the BAO-HNS. Local modifiations may improve matters, but significant increases in funding, manpower and equipment are required to achieve the stipulated standards. Moreover, criteria for referral have to be re-emphasized and patient education has to be addressed as these appear to contribute the longest delay in the diagnosis of head and neck tumours. 相似文献