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991.
992.
Dizziness is a common and often disabling disorder. In some people the cause of their dizziness is pathology or dysfunction of upper cervical vertebral segments that can be treated with manual therapy. The aim of the present study was to systematically review the literature on the manual therapy treatment of patients with cervicogenic dizziness, by identifying and evaluating both randomized controlled trials (RCTs) and non-RCTs (controlled clinical trials and non-controlled studies). Seven electronic databases were searched up to July 2003, article reference lists were screened and an expert panel elicited to obtain relevant trials. Nine studies met the inclusion criteria and key data was extracted. Two reviewers assessed the validity of the studies using the Cochrane format and found that all studies had low methodological quality. However, a consistent finding was that all studies had a positive result with significant improvement in symptoms and signs of dizziness after manual therapy treatment. Therefore, Level 3 evidence for manual therapy treatment of cervicogenic dizziness was obtained indicating it should be considered in the management of patients with this disorder provided there is evidence of improvement. This review has identified the need for further RCTs of acceptable methodological quality.  相似文献   
993.
The project was an investigation into whether changes in the expression of G-proteins underlie altered cell signaling in migraine and cluster headache. The basis for this assumption is that altered physiological responses are seen in migraineurs and that differences in cell signaling are detected biochemically in various cell types isolated from peripheral blood. Levels of three G-protein mRNAs—Gsα, Giα, and Gqα were quantified in lymphocytes from clinically well-defined migraine and cluster headache patients and correlated with headache type and influence of drug treatment. Giα mRNA was reduced by 50% in all migraine patients compared with control subjects; similarly in patients with or without aura, in patients with a migraine headache at the time of sampling, and patients in a quiescent state. No reduction in the levels of Gsα or Gqα mRNA were seen in migraine patients. A smaller reduction was seen in cluster headache patients, most marked in those without medication. Levels of Gsα. mRNA were significantly reduced in cluster headache patients compared with migraine patients. The marked down-regulation of Giα mRNA in migraine, whether quiescent or acute, indicates either an adaptive response to headache in this group of patients or that low levels of Giα mRNA make individuals more susceptible to migraine.  相似文献   
994.
The water soluble benzodiazepine derivative, midazolam, is used almost exclusively at our institution to produce sedation for numerous surgical procedures. Mild arterial oxygen desaturation has been reported in patients who have received as little as .04 mg/kg. A time series design study was undertaken to determine if there was any correlation between the decline in arterial oxygen percent saturation (SaO2) and the time at which sedation occurred and to establish the presence of any statistical significance in this decline. Thirty-one ASA I and II patients consisting of 8 females and 23 males requiring various minor orthopedic and general surgical procedures were studied. The total mean age of the population was 32.29 +/- 12.43 years (mean +/- SD). Fourteen patients had a smoking history, while 15 patients did not (2 patients were eliminated from the study for failure to demonstrate sedation, as characterized by either Verrill's sign or thickened speech following intravenous administration of midazolam). All patients arrived in the operating room unpremedicated and were administered .04 mg/kg midazolam intravenously. Arterial oxygen saturation was measured over a 10-minute period using pulse oximetry. Results were analyzed using regression analysis, a t-test for independent groups, and a one-way analysis of variance. There was no statistically significant difference in the decline in SaO2 between smokers and nonsmokers. Our study has shown that the mean onset of sedation using a dose of .04 mg/kg occurred between 3 and 4 minutes, with the peak fall in SaO2 occurring at the 3-minute interval irrespective of smoking history. The greatest mean drop in SaO2 was 95.84%. Midazolam, like its parent drug, diazepam, alters ventilatory mechanics.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
995.
Inadequate information is available on the care burden and severity of rheumatological diseases such as rheumatoid arthritis in West Africa. We therefore studied patients with rheumatoid arthritis presenting to a rheumatology unit in Nigeria and compared these with patients presenting to a British rheumatology unit. The West African patients were younger at onset of disease, less frequently had a family history, showed fewer extra-articular features and erosions and were less commonly rheumatoid factor positive. The overall mildness of the disease in the West Africans was striking.  相似文献   
996.
BACKGROUND: A "BeadChip" array permits reliable simultaneous DNA typing of single-nucleotide polymorphisms for minor blood groups. A high-throughput DNA analysis was studied as a routine method of phenotype prediction and software was developed to interpret and analyze the large volume of data points. STUDY DESIGN AND METHODS: DNA was extracted from whole blood of donors of known phenotypes and self-identified ethnicity. Analysis of single-nucleotide polymorphisms (SNPs) associated with 24 antigens of 10 blood group systems was performed with BeadChips (BioArray Solutions), and the results were compared to historical serologic typings. Phenotypes were predicted for individual samples, and phenotype prevalence was determined for ethnicities. The BeadChip was expanded to incorporate SNPs that silence the S antigen, validated, and tested with 369 DNA samples. A time-motion analysis was conducted. RESULTS: Results of BeadChip analyses were concordant with prediction of antigen negativity for 4,510 antigens. Eight discordant results were due to silencing of GYPB(S) and 16 were likely errors in recording serological results or data entry. The analyses produced 19,457 antigen-negative typings not serologically defined, identified 21 rare donors (Co(a-b+) [n = 1], Jo(a-) [n = 6], S-s-[n = 12], and K+k-[n = 2]), and determined allele frequencies and antigen prevalence for four ethnicities. The expanded panel detected 30 SS, 235 ss, 100 Ss, and 4 U- samples. The format processes 192 DNA samples (two plates) per 8-hour shift per technician, including automated data analysis and report generation. CONCLUSION: DNA analysis with BeadChip format, combined with computerized data entry and analysis, permits the prediction of minor blood group antigens.  相似文献   
997.
Dual or multiple cell populations, induced by chimeras, have been the subject of many studies. This long-standing fascination with chimeras has revealed a good deal of knowledge about human inheritance. Although historically most chimeras were caused by natural events, certain current medical intervention therapies are increasing the number of situations that can lead to a mixed cell population, that is, the chimeric condition, in humans. Medical therapies such as transfusion, stem cell transplantation, kidney transplantation, and artificial insemination induce temporary and sometimes permanent chimeras. Such natural or therapeutically induced presentations of chimerism can present challenging issues to the clinical immunohematology laboratory with regard to interpretation of results and subsequent patient management. The purpose of this review was to highlight some of these chimeric states and hypothesize how testing DNA from various tissues can cause apparent discrepancies between phenotype and genotype results.  相似文献   
998.
999.
Systemic inflammation is associated with sympathetic cardiac activation and decreased HRV (heart rate variability) in subjects at high risk of CAD (coronary artery disease). In the present study, we examined the influence of systemic inflammation, measured by CRP (C-reactive protein), on vagal HR (heart rate) control during behavioural relaxation in patients with CAD. It was hypothesized that CRP would be associated with decreased vagal HR modulation. Consecutive patients were screened 2 weeks prior to elective PTCA (percutaneous transluminal coronary angioplasty). The study was comprised of 29 subjects who represented the first and fourth quartiles of the CRP distribution: Low (0.47+/-0.07 microg/ml)- and High (8.19+/-1.95 microg/ml)-CRP groups respectively. Vagal HR control was quantified as RR high-frequency spectral power (0.15 to 0.40 Hz), and was assessed in log-transformed absolute units (logHF power). Near-IR particle immunoassay was used to determine high-sensitivity CRP concentration. Assessment entailed 5 min of silent reading and self-guided behavioural relaxation. RR logHF power was decreased in the High-CRP group across both assessment procedures (P=0.032). Behavioural relaxation increased RR logHF power for both the Low- and High-CRP groups (P=0.033). Hierarchical linear regression determined that CRP accounted for 18.9% of the variance in RR logHF power during behavioural relaxation (P=0.03), independent of baseline RR interval, cardiac medication, respiratory logHF power and body mass index. In conclusion, patients with CAD had augmented vagal HR control with behavioural relaxation, but this effect was moderated by the severity of CRP. Therefore it may be advisable to assess systemic inflammation in interventions aimed at improving neurocardiac regulation in patients with CAD.  相似文献   
1000.
Previous studies of the energy cost of wheelchair propulsion have used ergometers or tracks requiring little steering. We have measured minute ventilation (VE), oxygen consumption (VO2), carbon dioxide output (VCO2) and heart rate (HR) during exercise in a two arm, hand-rim propulsion wheelchair on a treadmill, and on three tracks of increasing tortuosity in eight able-bodied subjects. During propulsion at 0.6 m/sec, VE, VO2, and VCO2 were significantly greater on the track with the maximal steering component than on that with the minimal steering component, or on the treadmill with no steering component. Heart rate was significantly higher on the maximal compared to minimal steering component track. Exercise at speeds varying from 0.2 to 1.0 m/sec showed that VO2 and VCO2 were significantly higher on the medium steering component track than on the treadmill at speeds of 0.6 m/sec and above. We conclude that the effort of steering contributes significantly to the energy cost of wheelchair propulsion particularly at higher speeds.  相似文献   
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