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1.
目的:前期实验已证实针刺治疗偏头痛疗效优越。观察针刺对偏头痛大鼠脑内5-羟色胺1F和诱导型一氧化氮合酶mRNA表达的调控作用。方法:实验于2005-11/2006-05在中南大学湘雅医院中西医结合研究所实验室完成。①选用SD大鼠40只,按随机数字表法分为4组(n=10),除正常对照组外,其余3组均复制大鼠偏头痛模型。模型对照组只造模,不作其他处理;针刺治疗组造模后进行针刺;针刺预防组针刺后造模电刺激20min。针刺方法:针刺大鼠双侧太冲、阳陵泉穴20min。采用疏密波,电流强度0.3~0.6mA,留针20min,1次/d,共5次。②实验完毕后取脑干及三叉神经节匀浆,采用反转录-聚合酶链反应法测定5-羟色胺1F和诱导型一氧化氮合酶mRNA表达。结果:进入结果分析正常对照组10只,模型对照组、针刺治疗组、针刺预防组各9只,共脱失3只。①与正常对照组比较,模型对照组大鼠诱导型一氧化氮合酶mRNA表达显著增强(P<0.01),5-羟色胺1FmRNA表达显著减弱(P<0.01)。②与模型对照组比较,针刺预防组和针刺治疗组诱导型一氧化氮合酶mRNA表达明显减弱(P<0.01),5-羟色胺1FmRNA表达显著增强(P<0.01)。结论:针刺调控5-羟色胺1F和诱导型一氧化氮合酶mRNA的表达可能是针刺防治偏头痛的分子机制。  相似文献   
2.
Many case-control studies have been undertaken to assess whether and to what extent residential radon exposure is a risk factor for lung cancer. Nearly all these studies have been conducted in populations including smokers and nonsmokers. In this paper, we show that, depending on the nature of the joint effect of radon and tobacco on lung cancer risk, it may be very difficult to detect a main effect due to radon in mixed smoking and nonsmoking populations. If the joint effect is closer to additive than multiplicative, the most cost-effective way to achieve adequate statistical power may be to conduct a study among never-smokers. Because the underlying joint effect is unknown, and because many studies have been carried out among mixed smoker and nonsmoker populations, it would be desirable to conduct some studies with adequate power among never-smokers only.  相似文献   
3.
Retrorenal colon: implications for percutaneous diskectomy   总被引:1,自引:0,他引:1  
Helms  CA; Munk  PL; Witt  WS; Davis  GW; Morris  J; Onik  G 《Radiology》1989,171(3):864-865
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary.  相似文献   
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Cluster analysis of the MMPI has been utilized widely in the chronic low back pain literature to try to identify reliable patient subtypes predictive of treatment outcome. We extended this methodology to patients with heterogeneous chronic medical conditions by replicating prototypic MMPI cluster group profiles and by relating cluster groups to clinical baseline and outcome data. Subjects were two independent samples (n=254 and n=263) of chronically ill patients admitted to an inpatient medicine/psychiatry unit. Using a four-cluster solution, similar cluster profile groups were replicated in both samples. Consistent differences emerged between cluster groups on functional impairment, psychiatric diagnoses, depression, and psychosomatic symptoms. Cluster group membership also predicted changes in functional impairment and depression six months after treatment. Results are discussed in terms of similarities between chronic low back pain and chronic illness and tailoring treatment to different patient types.This research was supported in part by a grant from the Henry J. Kaiser Family Foundation.  相似文献   
7.
The membrane phenotype of human T cell colony progenitors and that of their clonal progeny was studied for expression of the T4 and T8 determinants. Using clonal culture conditions, the colonies were grown in semi-solid agar medium from peripheral blood cells. Clonality was assessed using the glucose-6-phosphate-dehydrogenase isoenzyme marker. Combination of this marker with the culture of sorted cell fractions allowed us to ascribe the colony progenitors to a subset of OKT4+ lymphocytes. The progeny consisted of the mixture of single OKT4+, single OKT8+ and double OKT4+8+ cells, as determined by double staining. Double staining was performed on mass-harvested colony cells and on individual colonies expanded in liquid culture with fresh interleukin 2. Expression of the OKT8 positivity on colony cells deriving from OKT4+ progenitors required an interaction with radioresistant OKT8+ cells that were co-cultured with these progenitors. Furthermore, the functional capacities of the cell progeny were assayed on the pokeweed mitogen-driven immunoglobulin production by B cells. It was found that OKT4+ colony cells were helper whereas OKT8+ colony cells were suppressor cells. It is concluded that a subset of OKT4+ peripheral blood T lymphocytes can generate colonies containing both helper OKT4+ cells and suppressor OKT8+ cells.  相似文献   
8.
OBJECTIVE: To update information on the workers of the Texaco mortality study to determine if the patterns of mortality have changed with 16 additional years of follow up. SUBJECTS AND METHODS: All workers were employed for > or = 5 years at company refineries, petrochemical plants, and research laboratories from 1947-93. The cohort now consists of 28,480 employees with an average of > or = 20 years of follow up. RESULTS: The overall mortality, and most cause specific mortalities were lower than or similar to those for the general population of the United States. For white men (86% of the cohort), there were 8873 observed deaths and 11,181 expected resulting in a significantly lower standardised mortality ratio (SMR) of 79. There were significant deficits for all the leading causes of death in the United States including all cancers, cancer of the lung, stroke, heart disease, respiratory disease, and accidents. Slightly increased mortality was found for cancer of the pancreas, cancer of the brain and central nervous system, leukaemia, and cancer of other lymphatic tissue. For cancer of the bone, the SMR was 162 (95% confidence interval (95% CI) 86 to 278), and for benign and unspecified neoplasms, it was 152 (95% CI 109 to 206). Overall mortality patterns for non-white men and women were similar to those for white men. Mortality patterns for white men were also examined by duration of employment, time first employed, location, and by job and process unit. There were significantly increased SMRs for brain cancer for those people employed as laboratory workers and on units with motor oil and for cancer of other lymphatic tissue for people employed on the fluid catalytic cracking unit. CONCLUSIONS: The results of the updated study showed a favourable mortality experience for employees in the Texaco mortality study compared with the United States population. There were a few increases found consistently including, but not limited to, brain cancer and cancer of other lymphatic tissue. These increases led to additional analyses that will be discussed in the accompanying paper.

 

  相似文献   
9.
A 1993 MRC working group on phenylketonuria suggested standardising blood phenylalanine measurements by taking blood samples at the same time each day. Since it is not known how representative of a 24 hour period a single phenylalanine concentration is, the aim of this study was to investigate the 24 hour variability of plasma phenylalanine in well controlled children with phenylketonuria. Sixteen subjects, 12 girls and four boys aged 1 to 18 years, had hourly venous blood samples collected for 13 hours between 09.00 and 21.00 on one day. Serial skin puncture blood specimens were then collected at 24.00, 03.00, and 06.00 within the same 24 hour period. All food and drink was weighed. The median variation in plasma phenylalanine concentration was 155 mumol/l/day, with a minimum of 80 and a maximum of 280. The highest concentration occurred in the morning between 6.00 and 9.00 in 63% of subjects; the lowest occurred between midday and midnight in 94%. Concentrations < 100 mumol/l occurred in 46% of children below 11 years, three having concentrations < 30 mumol/l for two, six, and seven hours respectively. Three of five subjects had concentrations above the MRC guidelines for 24% of the period studied. Except in two subjects, the blood concentrations did not rise in response to phenylalanine consumption. However, the greater the quantity of protein substitute taken between waking and the 16.00 specimen, the larger the decrease in daytime phenylalanine concentration (r = -0.7030) (p < 0.005). There is therefore wide variability in phenylalanine concentrations in a 24 hour period in children with phenylketonuria which is not reflected in a single observation. Further study is needed to investigate the effects of timing of protein substitute on the stability of phenylalanine concentrations.  相似文献   
10.
HYPOTHESIS: Amplification of the HER-2/neu oncogene in 25% of breast cancers is associated with a shortened disease-free survival. DESIGN: Retrospective analysis of a patient population referred to a tertiary care facility for HER-2/neu testing. The mean follow-up was 56 months. SETTING: Large, urban, tertiary care hospital. PATIENTS: From 1995 to 1999, a consecutive sample of 190 patients with breast cancer had tissue samples tested for overexpression of the cell surface oncoprotein by immunostaining (IM) or amplification of the HER-2/neu oncogene by fluorescence in situ hybridization or both. Forty-nine subjects were excluded because they had tissue samples tested at our institution but received their treatment elsewhere. All patients tested for HER-2/neu after diagnosis with breast cancer in 1999 (n = 47) were excluded from analysis because of short follow-up time. One patient was excluded who had in situ ductal carcinoma. The remaining 93 patients were analyzed. RESULTS: Of 93 patients, 40 (43%) had gene amplification. Overall, patients with oncogene amplification had a shorter median disease-free interval (22 months) compared with controls (40 months) (P =.003). Analysis by the Cox regression model showed that the HER-2/neu status remained significantly associated with time to relapse even after adjusting for age and tumor grade (P =.002; adjusted relative risk, 2.4; 95% confidence interval, 1.4-4.4). No association was found between gene amplification and tumor grade (P =.98), estrogen/progesterone receptor status (P = .29 and P = .43, respectively), or lymph node status (P = .98). Seventy-two patients (77%) eventually had disease recurrence, with 18 (25%) of these recurring locally. CONCLUSIONS: The HER-2/neu oncogene is an independent prognostic indicator of a subset of breast cancers that are at high risk of early recurrence, regardless of tumor grade, estrogen/progesterone receptor status, and lymph node status. Patients amplifying the HER-2/neu oncogene have a shorter disease-free survival than patients without the oncogene.  相似文献   
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