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71.
72.
SK Roy AM Tomkins SM Akramuzzaman RH Behrens R Haider D Mahalanabis G Fuchs 《Archives of disease in childhood》1997,77(3):196-200
OBJECTIVE: To evaluate the impact of zinc supplementation on the clinical course, stool weight, duration of diarrhoea, changes in serum zinc, and body weight gain of children with acute diarrhoea. DESIGN: Randomised double blind controlled trial. Children were assigned to receive zinc (20 mg elemental zinc per day) containing multivitamins or control group (zinc-free multivitamins) daily in three divided doses for two weeks. SETTING: A diarrhoeal disease hospital in Dhaka, Bangladesh. PATIENTS: 111 children, 3 to 24 months old, below 76% median weight for age of the National Center for Health Statistics standard with acute diarrhoea. Children with severe infection and/or oedema were excluded. MAIN OUTCOME MEASURES: Total diarrhoeal stool output, duration of diarrhoea, rate of weight gain, and changes in serum zinc levels after supplementation. RESULTS: Stool output was 28% less and duration 14% shorter in the zinc supplemented group than placebo (p = 0.06). There were reductions in median total diarrhoeal stool output among zinc supplemented subjects who were shorter (less than 95% height for age), 239 v 326 g/kg (p < 0.04), and who had a lower initial serum zinc (< 14 mmol/l), 279 v 329 g/kg (p < 0.05); a shortening of mean time to recovery occurred (4.7 v 6.2 days, p < 0.04) in those with lower serum zinc. There was an increase in mean serum zinc in the zinc supplemented group (+2.4 v -0.3 mumol/l, p < 0.001) during two weeks of supplementation, and better mean weight gain (120 v 30 g, p < 0.03) at the time of discharge from hospital. CONCLUSIONS: Zinc supplementation is a simple, acceptable, and affordable strategy which should be considered in the management of acute diarrhoea and in prevention of growth faltering in children specially those who are malnourished. 相似文献
73.
74.
Elizabeth A. Platz Maria Elena Martinez Francine Grodstein Charles S. Fuchs Graham A. Colditz Meir J. Stampfer Edward Giovannucci 《Cancer causes & control : CCC》1997,8(6):894-903
Evidence for an effect of reproductive factors on colorectal carcinogenesis is inconsistent and little is known about their
role in development of precursor adenomatous polyps. We evaluated the relation between reproductive factors and distal colorectal
adenomas (n = 982) during14 years of follow up of 26,983 participants in the Nurses' Health Study(United States). The women
were free of diagnosed cancer or polyps in 1980,underwent endoscopy 1980-94, and had reported on their parity, oral contraceptive
(OC) use, and ages at menarche, first term-pregnancy, and menopause. We calculated relative risks (RR) and 95 percent confidence
intervals (CI) using multiple logistic regression. Women with higher parity had an increased risk of adenomas of the distal
colorectum (P trend = 0.004;6+ cf 0 parity: RR = 1.3, CI = 0.9-1.8) or distal colon (P trend = 0.002, RR= 1.7, CI = 1.2-2.6).
This association was significantly stronger among women with a family history of colorectal cancer ( P interaction = 0.03);
comparing6+ term-pregnancies with nulliparity, among those with a family history, the RR for distal colon adenoma was 3.2
(CI = 1.4-7.2), while among those without a family history, the RR was 1.3 (CI = 0.8-2.2). We observed no association for
distal colorectal adenoma and age at menarche, age at first term-pregnancy, ever use of OCs, or menopausal status. Further
work is needed to clarify the relation of parity with colon adenoma risk.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
75.
We studied the relationship between nutritional status and infection due to specific enteropathogens in young children with diarrhoea. Overall, 26% of the children were severely underweight, 27% were severely wasted and 19% were severely stunted. Children with Shigellae and V. cholerae O1 were significantly more severely underweight, wasted and stunted than those with rotavirus diarrhoea ( p < 0:0001). Our results indicate that an effective nutrition programme for young children might have greater impact on diarrhoeal illness caused by Shigella and V. cholerae than by rotavirus diarrhoea. 相似文献
76.
Isolation and characterization of propagable cell lines (HUNC) from the androgen-sensitive Dunning R3327H rat prostatic adenocarcinoma 总被引:1,自引:0,他引:1
Presnell SC; Borchert KM; Glover WJ; Gregory CW; Mohler JL; Smith GJ 《Carcinogenesis》1998,19(4):585-590
The Dunning H rat prostate tumor (R3327H) is a widely used experimental
model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been
characterized as androgen-sensitive, androgen-receptor (AR) positive,
prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To
date, the tumor has been maintained by serial passage in vivo because of
the lack of an in vitro cell line that retains the characteristics of the
in vivo tumor. The objective of the present study was to establish a
propagable cell line from R3327H adenocarcinoma that maintained androgen
sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in
vivo R3327H tumor was dissociated with collagenase and placed into
Richter's improved media (with supplements). A cytokeratin-positive
epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line
(HUNC-S) were generated from the primary culture, subcultured continuously
for >300 days, and passaged >50 times. Survival of the HUNC-E cell
line in vitro depended on several media supplements, including
nicotinamide, insulin, transferrin, selenium and epidermal growth factor
(EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the
culture period, as confirmed by immunocytochemistry and Western blot
analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT)
to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent
growth and PSA production, which demonstrated the androgen-sensitive nature
of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1
ratio and introduced subcutaneously into syngeneic male hosts, tumors
formed in 2/3 animals with an average latency of 7 months. RT-PCR and
immunocytochemical characterization of the HUNC cell lines revealed that
the cells expressed several growth factors and their cognate receptors,
including HGF, TGF-alpha and the TGF-betas, indicating the establishment of
potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S
CaP cell lines, which retain the characteristics of the epithelial and
stromal components of the in vivo R3327H tumor, will allow a more thorough
and informative molecular and biological analysis of prostatic
adenocarcinoma.
相似文献
77.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献
78.
Dietary marine n-3 fatty acids in relation to risk of distal colorectal adenoma in women. 总被引:2,自引:0,他引:2
Kyungwon Oh Walter C Willett Charles S Fuchs Edward Giovannucci 《Cancer epidemiology, biomarkers & prevention》2005,14(4):835-841
Epidemiologic studies of dietary marine n-3 fatty acids and risk of colorectal cancer have been inconsistent, and their relation to risk of colorectal adenoma has not been evaluated in detail. We examined dietary marine n-3 fatty acids and the ratio of marine n-3 to total n-6 fatty acids (n-3/n-6 ratio) in relation to risk of adenoma of the distal colon or rectum among 34,451 U.S. women who were initially free of colorectal cancer or polyps, who completed a semiquantitative food frequency questionnaire in 1980, and who underwent endoscopy from 1980 to 1998. We documented 1,719 distal colorectal adenoma cases (705 large adenomas, 897 small adenomas, 1,280 distal colon adenomas, and 505 rectal adenomas) during 18 years of follow-up. Neither dietary marine n-3 fatty acids nor n-3/n-6 ratio were associated with risk of total distal colorectal adenoma after adjustment for age and established risk factors [multivariable relative risk (RR) for extreme quintiles of dietary marine n-3 fatty acids = 1.04; 95% confidence interval (95% CI), 0.84-1.27, P(trend) = 0.66; RR for extreme quintiles of n-3/n-6 ratio = 1.02; 95% CI, 0.83-1.25; P(trend) = 0.86]. Similarly, no significant associations were observed separately for distal colon or rectal adenoma. However, higher intake of dietary marine n-3 fatty acids was nonsignificantly but suggestively inversely associated with large adenoma (RR, 0.74; 95% CI, 0.54-1.01; P(trend) = 0.16) but directly associated with small adenoma (RR, 1.36; 95% CI, 1.02-1.81; P(trend) = 0.09). Our findings do not support the hypothesis that a higher intake of marine n-3 fatty acids or a higher n-3/n-6 ratio reduces the risk of distal colorectal adenoma but are suggestive that higher intake may reduce the progression of small adenomas to large adenomas. 相似文献
79.
马蓝的化学成分研究 总被引:15,自引:0,他引:15
Seven compounds have been isolated from the whole plant of Strobilanthes cusia (Nees) O. Ktze. Three of them are triterpenes (Ⅰ~Ⅲ), two are indole alkaloids (Ⅳ, Ⅴ), two are quinazolinone alkaloids (Ⅵ, Ⅶ). On the basis of spectral analysis and physicochemical properties, their structures were established as lupeol (Ⅰ), betulin (Ⅱ), lupenone (Ⅲ), indigo (Ⅳ), indirubin (Ⅴ), 4 (3H)-quinazolinone (Ⅵ), 2, 4 (1H, 3H)-quinazolinedione (Ⅶ). Ⅵ and Ⅶ were found from natural plant for the first time.The results of the pharmacological tests demonstrate that compound Ⅴ has anticancer activity and compound Ⅵ has hypotensive action. Compound Ⅶ can be quantitatively determined by HPLC, which may serve as a quality control standard for materia medica and its preparations. Compounds Ⅵ and Ⅶ have been confirmed by means of synthesis. 相似文献
80.