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Trasditional Chinese medicine is based on inductive-synthetic reasoning with regard to all life processes, in contrast to the causal-analytic orientation in our Western medicine. This philosophical approach is based on a system of comparisons (equivalents), referred to as Yin and Yang. Vital functions are seen as "energizing" processes, whereby the acupuncture points and the system of meridians are seen as a means of regulation for this "energy". A disturbed balance in this energy results in illness. The therapy according to the acupuncture method is to acheive a balance in the disturbed flow of energy by means of acupuncture points. By utilizing biophysical methods of measurement, it is possible to prove that a change in this energy takes place. The complex active principle which results in the effectiveness of acupuncture includes neurophysiological, biochemical and biophysical functional processes.  相似文献   
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The aim of this study was to describe the experience of screening women under the age of 50 years with a family history of breast cancer. 1259 women attended the Family History Clinic in Manchester for their first and subsequent consultations between 30 September 1992 and 30 April 1997. All women were under the age of 50 years at the initial consultation and had a lifetime risk of breast cancer of 1 in 6 or greater. Seven prevalent, seven incident and two interval cancers were detected. The number of invasive cancers expected to occur if this high risk population had not been screened was 8.45 (in 2722 person years at risk). 12 invasive cancers were detected, giving a ratio of 1.42 (95% confidence interval 0.73-2.48). The overall cancer detection rates in this young, at risk population were similar to those in older women in the National Health Service Breast Screening Programme. The number of cancers detected in the study was greater than expected in this population. As the numbers were small, a national trial needs to be undertaken to confirm these results and to determine the long term effects of screening.  相似文献   
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OBJECTIVES: This study explores reactions to low-level chemical challenge, aiming at the development of test procedures for assessing individual sensitivity to smells and chemicals. METHODS: Subjects with symptoms and neuropsychological test results compatible with toxic encephalopathy type 2A (TE-2A) and 2B (TE-2B) and unexposed referents (N=12 in each group) were challenged in an exposure chamber. Toluene exposure was started at 11 mg/m3, and it followed a geometric progression scale with a ratio of 2, until reaching 180 mg/m3. In a counterbalanced design, the subjects were similarly exposed to n-butyl acetate starting at a concentration of 14 mg/m3 and increasing to 228 mg/m3. At each exposure level, smell intensity was measured on a 7-step category scale. Mucous membrane irritation and annoyance reactions were rated on visual analogue scales. RESULTS: Both TE groups showed high sensitivity to the low-level solvent challenge, which provoked immediate annoyance and fatigue reactions. In particular the TE-2B group related smell intensity to various annoyance dimensions during exposure to n-butyl acetate, a pattern not observed during toluene exposure. The reference group clearly separated smell intensity and annoyance reactions in both exposure conditions. CONCLUSIONS: The reaction of the TE cases suggests that chemical sensitivity can be distinguished from normal annoyance reactions by the inability to differentiate between smell intensity and an experience of irritation from mucous membranes in air concentrations well below the trigeminal irritation threshold level. Fatigue coreactivity in challenges to single substances below the neurotoxic level may also be important.  相似文献   
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The membrane fluidity characteristics of multilamellar (MLV) and extruded liposomes prepared with kaempferol (K), kaempferol-3-glucoside (KG), (−)-epigallocatechin (EGC) or (−)-epigallocatechin-3-gallate (EGCG) are presented. Kaempferol caused the highest increase in fluorescence polarisation of DPH in both liposomes (other compounds had not) indicating that K with nK/nLip below 0.2 or 0.1 decreased the membrane fluidity, while at higher molar ratios the membrane fluidity increased. EPR measurements with MLV and spin probes MeFASL(10,3) and MeFASL(2,11) showed a significant decrease in fluidity in the upper part of the membrane for all flavonoids measured, and in the core of the membrane an increase in fluidity for EGCG and EGC. Computer simulation of the EPR spectra showed that the membrane of the MLV used was composed of at least three coexisting domain types with different fluidity and that the order parameter of the most ordered domains is responsible for membrane fluidity alterations.  相似文献   
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Cystic fibrosis (CF)--an autosomal recessive disorder caused by mutations in CF transmembrane conductance regulator (CFTR) and characterized by abnormal chloride conduction across epithelial membranes, leading to chronic lung and exocrine pancreatic disease--is less common in African-Americans than in Caucasians. No large-scale studies of mutation identification and screening in African-American CF patients have been reported, to date. In this study, the entire coding and flanking intronic sequence of the CFTR gene was analyzed by denaturing gradient-gel electrophoresis and sequencing in an index group of 82 African-American CF chromosomes to identify mutations. One novel mutation, 3120+1G-->A, occurred with a frequency of 12.3% and was also detected in a native African patient. To establish frequencies, an additional group of 66 African-American CF chromosomes were screened for mutations identified in two or more African-American patients. Screening for 16 "common Caucasian" mutations identified 52% of CF alleles in African-Americans, while screening for 8 "common African" mutations accounted for an additional 23%. The combined detection rate of 75% was comparable to the sensitivity of mutation analysis in Caucasian CF patients. These results indicate that African-Americans have their own set of "common" CF mutations that originate from the native African population. Inclusion of these "common" mutations substantially improves CF mutation detection rates in African-Americans.  相似文献   
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