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31.
Claus Jacob Alexander Y. Safronov Sonia Wilson H.Allen O. Hill Tim F. Booth 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》1997,431(1):7-10
A novel chiral redox-active ferrocene compound (FcVI) with amphiphilic properties has been synthesized. Cryogenic Transmission Electron Microscopy (cryo-TEM) has been used to estimate the shape and size of the FcVI aggregates in solution. Uni- and multi-lamellar vesicles (between 40 and 300 nm in diameter) were observed in water. Large particles (of more than 1 μm in diameter) with a hexagonal fine structure were found in 50 mM aqueous Na2SO4 solution. Sonication transformed the latter into ‘rosette’-like structures. Cyclic voltammetry has been employed to investigate the electrochemical properties of FcVI. The amphiphile adsorbed on graphite electrodes and a reversible electrochemical behaviour, characteristic of ferrocene, was observed with redox potentials between 330 and 350 mV. 相似文献
32.
JANET E. PRITCHARD MSc APD MDAA CARYL A. NOWSON PhD MDAA JOHN D. WARK MBBS PhD FRACP 《Journal of the American Dietetic Association》1997,97(1):37-42
Objective To compare changes in total and regional body composition using dual energy X-ray absorptiometry (DEXA) after subjects lost weight through change in diet or exercise.Design A 12-month, randomized, controlled study of two weight-loss interventions — low-fat diet ad libitum or moderate, unsupervised exercise — in free-living, middle-aged men. Compliance was determined at monthly measurement sessions through food records and activity logs; DEXA scans were performed every 3 months.Subjects/setting Fifty-eight overweight men (mean body mass INDEX=29.0±2.6; mean AGE=43.4±5.7 years) recruited from a national corporation were assigned randomly to diet, exercise, or control groups.Interventions One group reduced dietary fat to 26.4% of energy intake but kept activity unchanged; another group self-selected aerobic exercise (three sessions per week at 65% to 75% maximum heart rate) but kept diet unchanged. A control group maintained weight.Main outcome measures At 12 months, measurements of weight, total and regional fat mass and lean mass, energy intake, and percentage dietary fat; physical activity indexes. Statistical analyses Results were analyzed using paired t tests and analysis of variance.Results Mean weight loss was 6.4±3.3 kg in dieters and 2.6+3.0 kg in exercisers; control subjects maintained weight. DEXA scans revealed that 40% of dieters’ weight loss was lean tissue; more than 80% of weight lost by exercisers was fat. Exercisers maintained limb lean tissue and lost fat mass.Conclusions Greater total weight and lean tissue loss occurred when subjects lost weight through a low-fat diet consumed ad libitum than when subjects participated in unsupervised aerobic exercise. Use of DEXA enabled identification of progressive total and regional changes in fat and lean tissue. J Am Diet Assoc. 1997; 97:37–42. 相似文献
33.
J A SCUDAMORE MA MB BChir P J H Tooley MBBS MRCGP DRCOG R J Allcorn BSc DPhil MRPharmS 《International journal of clinical practice》1992,46(4):260-263
Vaginal candidosis is one of the most common infections of the vagina and the first accredited record of the disease appeared in 1849. Over the years the terms ‘candidiasis’ and ‘candidosis’ have been used, but it is generally accepted now that the terms are synonymous, and the term most commonly in use today is ‘candidosis’. Mainly caused by the yeast Candida albicans, the condition is characterised by intense inflammation of the vaginal mucosa and a curdy, off-white discharge; it is often associated with severe vulval itching and possibly burning pain. The severity of symptoms seems to vary greatly from patient to patient and the reason for this is unclear. It is suggested that in some patients there may be an element of hypersensitivity. Vaginal candidosis may occur in children but is most common in adults and only sometimes affects the elderly. The majority of women will suffer at least one attack of vaginal candidosis during their lifetime, and there are several predisposing factors such as diabetes, pregnancy and antibiotics. Some authorities consider the condition more frequent in those taking oral contraceptives or other hormones. 相似文献
34.
Clinical correlates of high signal lesions on magnetic resonance imaging in Alzheimer's disease 总被引:1,自引:0,他引:1
David A. Bennett David W. Gilley Robert S. Wilson Michael S. Huckman Jacob H. Fox 《Journal of neurology》1992,239(4):186-190
Summary The pathophysiology and clinical significance of high signal lesions, visualized on magnetic resonance imaging (MRI) in patients with Alzheimer's disease (AD), remain controversial. Since they are known to correlate with vascular disease and vascular risk factors, we reviewed the clinical correlates of periventricular high signal (PVH) and subcortical white matter lesions (WML) in a sample of 106 patients with probable AD, excluding persons with treated vascular risk factors or symptomatic cerebrovascular and cardiovascular disease. Grade 2 PVH were seen in 26 (25%) and scattered WML were identified in 29 (18%). PHV were associated with advancing age and gait disturbance. WML were associated with gait disturbance and incontinence. Neither radiologic finding was related to dementia severity. The findings suggest that these lesions are common in patients with AD even when those with evidence of cerebrovascular disease are excluded; their presence, therefore, should not preclude a diagnosis of AD. Additionally, the data suggest that HSL on MRI may be one of many risk factors associated with functional disability in persons with probable AD. 相似文献
35.
36.
N-Nitrosodibutylamine (NDBA) and its omega-oxidized metabolites N-nitrosobutyl-4-hydroxybutylamine (4-OH-NDBA) and N-nitrosobutyl-3-carboxypropylamine (BCPN) are potent urinary bladder carcinogens. To study putative organ specific activation of BCPN, its alpha-oxidation by liver and urinary bladder microsomal fractions was investigated in comparison to NDBA and 4-OH-NDBA. Additionally, induction of DNA single strand breaks (SSB) was monitored in hepatocytes and in a human lymphoblastoid cell line (Namalva) in the presence and absence of external metabolic activation, including N-nitroso-t-butyl-n-butylamine as a negative control. BCPN was alpha-hydroxylated and dealkylated at both alkyl chains in small rates (about 1 nmol x mg protein-1 x 60 min-1) by microsomes from rat liver and pig urinary bladder epithelium. NDBA and 4-OH-NDBA were dealkylated at similarly low rates by pig urinary bladder microsomes, in strong contrast to the high debutylation rates observed for rat liver microsomes. Correspondingly, SSB induction by NDBA and 4-OH-NDBA was observed in Namalva cells with NDBA and 4-OH-NDBA in the presence of PB-induced rat liver microsomes but not with urinary bladder microsomes or without external activation. BCPN did not induce DNA-damage in Namalva cells (with or without external activation) or in rat hepatocytes. Significant induction of sister chromatid exchanges (SCEs) and micronuclei, however, was observed in Namalva cells after incubation with NDBA and BCPN. Our data suggest activation of BCPN via alpha-oxidation in the urinary bladder, even though activation rate in-vitro is so low that a positive response is not detectable by several short-term tests. 相似文献
37.
38.
We dissected 20 preserved Caucasian cadaveric upper limbs looking at the relation of the superficial branch of the radial nerve (SBRN) to the brachioradialis tendon. SBRN emerged from deep to superficial position by piercing the brachioradialis tendon near its dorsal border in four limbs. The resulting dorsal tendinous band compressed the nerve and prevented longitudinal gliding movement during ulnar flexion. This is likely to increase the risk of chronic compression neuropathy (Wartenberg's syndrome). In two of these four limbs, there was a communication between the SBRN and lateral cutaneous nerve of the forearm. No such communication was found in the remaining 16 forearms. This communication could contribute to the minimal area of sensory loss observed in Wartenberg's syndrome. We recommend that this anatomical anomaly is looked for and if present dealt with during surgical treatment of Wartenberg's syndrome, as it is likely to predispose to chronic compression neuropathy. 相似文献
39.
K Prakash H Ramesh G Jacob A Venugopal V Lekha D Varma G N Ramesh P Augustine 《Indian journal of gastroenterology》2004,23(6):209-213
BACKGROUND: Intrahepatic stones, though common in East Asia, are uncommon in India. There is paucity of data from India regarding the treatment and long-term outcome of patients with intrahepatic stones. METHODS: We retrospectively analyzed medical records of 35 patients with intrahepatic stones who had been treated surgically. Endoscopic biliary drainage had been used in patients who presented with acute cholangitis. Intraoperative stone clearance was confirmed by choledochoscopy and intraoperative cholangiography. Outcome of surgery, frequency and subsequent management of recurrent intrahepatic stones, and factors associated with stone recurrence and cholangitis were analyzed. RESULTS: Twenty-one (60%) patients had bilobar disease. Eight patients underwent hepatectomy and 16 hepatico-jejunostomy with access loop; 12 of these were jejuno-duodenal anastomoses. Postoperative morbidity was observed in 10 patients (29%). Recurrence of stones occurred in 12 patients (34%) and cholangitis in 9 patients (26%). Presence of bilobar disease and associated biliary strictures were associated with recurrent cholangitis (p< 0.05). Two patients (6%) required re-operation for recurrent cholangitis. Complete removal of recurrent stones using conventional endoscope was possible through jejuno-duodenostomy in all 5 cases who had this type of access loop construction. CONCLUSION: Surgical treatment for intrahepatic stones depends on the site of involvement. Construction of a jejuno-duodenal access loop in patients with bilobar disease and intrahepatic strictures is helpful in facilitating postoperative stone clearance. A multidisciplinary approach is beneficial especially when the disease is bilobar and recurrent in type. 相似文献