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21.
KRISTEN BRUINSMA MS DOUGLAS L. TAREN PhD 《Journal of the American Dietetic Association》1999,99(10):1249-1256
Although addictive behavior is generally associated with drug and alcohol abuse or compulsive sexual activity, chocolate may evoke similar psychopharmacologic and behavioral reactions in susceptible persons. A review of the literature on chocolate cravings indicates that the hedonic appeal of chocolate (fat, sugar, texture, and aroma) is likely to be a predominant factor in such cravings. Other characteristics of chocolate, however, may be equally as important contributors to the phenomena of chocolate cravings. Chocolate may be used by some as a form of self-medication for dietary deficiencies (eg, magnesium) or to balance low levels of neurotransmitters involved in the regulation of mood, food intake, and compulsive behaviors (eg, serotonin and dopamine). Chocolate cravings are often episodic and fluctuate with hormonal changes just before and during the menses, which suggests a hormonal link and confirms the assumed gender-specific nature of chocolate cravings. Chocolate contains several biologically active constituents (methylxanthines, biogenic amines, and cannabinoid-like fatty acids), all of which potentially cause abnormal behaviors and psychological sensations that parallel those of other addictive substances. Most likely, a combination of chocolate's sensory characteristics, nutrient composition, and psychoactive ingredients, compounded with monthly hormonal fluctuations and mood swings among women, will ultimately form the model of chocolate cravings. Dietetics professionals must be aware that chocolate cravings are real. The psychopharmacologic and chemosensory effects of chocolate must be considered when formulating recommendations for overall healthful eating and for treatment of nutritionally related health issues. 相似文献
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JORDAN M. PRUTKIN M.D. KRISTEN K. PATTON M.D. 《Pacing and clinical electrophysiology : PACE》2009,32(12):e36-e39
We report a patient with a clinical history of inclusion‐body myositis presenting with monomorphic ventricular tachycardia. Comprehensive evaluation demonstrated no evidence of coronary artery disease or cardiomyopathy. Programmed electrical stimulation induced the patient's clinical tachycardia as well as a second monomorphic ventricular tachycardia of a different morphology. At the time of implantable cardioverter‐defibrillator implant, biopsy of the pectoralis major muscle was performed, which confirmed the diagnosis of inclusion‐body myositis. Ventricular tachycardia has not previously been reported in a patient with inclusion‐body myositis. 相似文献
25.
DOES INCREASED NEEDLE BIOPSY SAMPLING OF THE PROSTATE DETECT A HIGHER NUMBER OF POTENTIALLY INSIGNIFICANT TUMORS? 总被引:6,自引:0,他引:6
THERESA Y. CHAN DAVID Y. CHAN KRISTEN LECKSELL RAY E. STUTZMAN JONATHAN I. EPSTEIN 《The Journal of urology》2001,166(6):2181-2184
PURPOSE: Several studies have documented that increased biopsy sampling, that is 6 versus 12 biopsy cores, can detect more prostate cancer. It is unknown whether increased sampling of the prostate will detect a higher number of potentially insignificant tumors. MATERIALS AND METHODS: We searched the surgical pathology files at The Johns Hopkins Hospital for patients in whom prostate needle biopsy was performed by a single urologist between April 1993 and April 2000, and subsequently underwent radical prostatectomy. Patients who underwent radical prostatectomy and had 8 core biopsies or less between March 1994 and August 1999 were also studied. Clinically significant tumors were defined as those with volume greater than 0.5 cc, Gleason score 7 or greater or nonorgan confined disease. RESULTS: A total of 297 patients with a mean age of 60 years (range 36 to 75) were evaluated. Group 1 consisted of 107 men with 8 core biopsies or less, including 51 with 6, and group 2 comprised 190 men with 9 cores or greater, including 145 with 12. The 2 groups were equal in regard to prostate specific antigen, age, digital rectal examination and transrectal ultrasound gland volume at biopsy. The only difference between the groups was a higher number of cores with cancer in group 2 (mean 2.8 versus 2.1, p = 0.0006). Of the patients who underwent radical prostatectomy 59.6% had Gleason score 6 or less, 26.3% 3+4, 6.7% 4+3 and 7.4% 8 to 9. There were 12.4% of patients with positive margins, 36.4% extraprostatic extension, and 5.4% seminal vesicle invasion and/or lymph node metastasis. Tumor volumes averaged 1.1 cc (range 0.01 to 10.7) and 60.9% of tumors were greater than 0.5 cc. Clinically significant tumors were seen in 77.4% of patients in group 1 and 74.6% in group 2. There was no significant difference in Gleason score, margin status, tumor volume, seminal vesicle invasion, or lymph node metastasis between groups 1 and 2, or in a subset analysis of men with 6 versus 12 core biopsies. However, patients in whom cancer was diagnosed with 9 core biopsies or greater were more likely to have organ confined disease (p = 0.02). CONCLUSIONS: Although increased sampling of the prostate does not increase the detection of potentially insignificant tumors, it does appear to detect earlier stage cancer. 相似文献
26.
EXTENSIVE MODIFICATION OF PROTEIN AMINO GROUPS BY REDUCTIVE ADDITION OF DIFFERENT SIZED SUBSTITUENTS
The amino groups of ovomucoid, lysozyme and ovotransferrin have been extensively alkylated by reacting the proteins with various carbonyl reagents in the presence of sodium borohydride. The extent of modification ranged from 40 to 100%. Essentially monosubstitution was obtained with acetone, cyclopentanone, cyclohexanone and benzaldehyde, while 20–50% disubstitution was obtained with N-butanal and nearly 100% disubstitution was obtained with formaldehyde. Both the methylated and isopropylated derivatives of all three proteins were soluble and retained almost full biochemical activities, but introduction of the larger substituents caused precipitation with lysozyme and ovotransferrin. 相似文献
27.
Abstract – Specific serum antibody activities of the IgG, IgA and IgM isotypes against lipopolysaccharide (LPS) prepared from Bacteroides gingivalis were measured by an enzyme-linked immunosorbent assay (ELISA) in a group of 12 periodontally healthy subjects and a group of 26 patients with periodontitis. The latter group received periodontal therapy, completed within about 1 yr. A serum sample was obtained from each participant at the first periodontal examination; a second sample was taken about 2 yr later. The mean antibody levels calculated for the healthy group did not change significantly between the first and second examination. The correlation coefficients computed between the two sets of measurements were 0.93, 0.90 and 0.96 for IgG, IgM and IgA respectively ( P < 0.05). Periodontal treatment significantly improved the clinical status of the patients and was followed by a statistically significant mean reduction in specific antibody levels to the LPS preparation (IgG: 15%, IgA: 30% and IgM: 15%). 相似文献
28.
Abstract— Three different cell lines of human origin, i.c. human epithelica cells (NCTC 2544), and epithelial and fibroblast like cells from human gingiva, were tested for their sensitivity fo three different dental resin-based restorative materials using four different assay techniques. The techniques applied were cell growth measurements by cell number, 53 Cr-release, Agar overlay with neutral red staining and colony formation. The ranking of teh cells according to their sensitivity ot the materials varied with the assay technique applied, with no cell line being consistently more sensitive than the others. It is also suggested that the type of medium applied could be important for the result obtained. 相似文献
29.
Fluoride retention in sound and demineralized enamel in vivo after treatment with a fluoride varnish (Duraphat) 总被引:1,自引:0,他引:1
Abstract – The retention of alkali soluble (CaF2) and alkali insoluble (fluorapatite) fluoride in sound enamel and demineralized enamel 2 wk after application of Duraphat was investigated in a group of orthodontic patients from whom pairs of homolog premolars were to be extracted. Demineralization of the enamel was induced during a 4-wk period prior to application of fluoride by applying orthodontic bands to the premolars. The bands also remained attached to the teeth during and after application of fluoride (2 wk) to maintain a cariogenic environment. Three consecutive enamel layers (~5 μm) were subsequently etched off. A significant uptake of fluoride in the first and second layer of sound enamel and in all the three enamel layers of demineralized enamel was found. More fluoride was found in demineralized enamel and a higher proportion of this fluoride was found to be in an alkali insoluble form compared with the fluoride in sound enamel. The SEM study showed a rough enamel surface after three consecutive acid etchings. The etching pattern differed within the etched area. It was suggested that the variation in etching pattern might be due to differences in orientation of the crystallites and the original surface morphology. 相似文献
30.
abstract – A cell culture method has been used to study the effect of zinc phosphate cement (De Trey's Zink Zement Improved®), zinc silicophosphate cement (Fluoro-Thin®) and polycarboxylate cement (Durelon®) on animal cells. Disks (30 × 1 mm) of the materials were placed in the center of plastic Petri dishes and subsequently incubated with human epithelial cells. Cell multiplication, medium pH and the release of cement constituents were measured. All three cements exhibited a cytotoxic effect, which was most pronounced in the cultures with zinc silicophosphate cement and polycarboxylate cement. The results also indicated that cell growth on the surface of the disks is a more sensitive indicator of cytotoxicity than cell growth around the disks. pH of the medium was only slightly affected in cultures with polycarboxylate cement, whereas a decrease was found in cultures with zinc phosphate cement and especially with zinc silicophosphate cement. A rapid release of phosphate was found in cultures with zinc silicophosphate cement. Zinc was released into the medium from disks of zinc phosphate cement, zinc silicophosphate cement and polycarboxylate cement – exceeding the toxicity level for the present cell line after 24 h. In cultures with zinc silicophosphate cement and polycarboxylate cement the release of fluoride reached toxic levels within the same time interval. 相似文献