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991.
992.
Green tea in chemoprevention of cancer 总被引:13,自引:0,他引:13
The concept of prevention of cancer using naturally occurring substances
that could be included in the diet consumed by the human population is
gaining increasing attention. Tea, next to water, is the most popularly
consumed beverage in the world and it is grown in about 30 countries.
Abundant data, amassed from several laboratories around the world in the
last ten years, provided convincing evidence that polyphenolic antioxidants
present in tea afford protection against cancer risk in many animal-tumor
bioassay systems. The epidemiological studies, though inconclusive, have
also suggested that the consumption of tea is associated with a lowered
risk of cancer. Much of this work has been done on green tea; less is known
about black tea. Green tea contains many polyphenolic antioxidants, and
(-)-epigallocatechin-3- gallate (EGCG) is the key polyphenolic antioxidant
believed to be responsible for most of the cancer chemopreventive
properties of green tea. This review will discuss these effects and the
molecular mechanisms associated with the biological response to green-tea
polyphenols.
相似文献
993.
Use of positron emission tomography in evaluation of brachial plexopathy in breast cancer patients 总被引:2,自引:0,他引:2
18-Fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) has previously been used successfully to image primary and metastatic breast cancer. In this pilot study, 19 breast cancer patients with symptoms/signs referrable to the brachial plexus were evaluated with 18FDG-PET. In 11 cases computerized tomography (CT) scanning was also performed. Of the 19 patients referred for PET study, 14 had abnormal uptake of 18FDG in the region of the symptomatic plexus. Four patients had normal PET studies and one had increased FDG uptake in the chest wall that accounted for her axillary pain. CT scans were performed in 9 of the 14 patients who had positive brachial plexus PET studies; six of these were either normal or showed no clear evidence of recurrent disease, while three CTs demonstrated clear brachial plexus involvement. Of two of the four patients with normal PET studies, one has had complete resolution of symptoms untreated while the other was found to have cervical disc herniation on magnetic resonance imaging (MRI) scan. The remaining two patients almost certainly had radiation-induced plexopathy and had normal CT, MRI and PET study. These data suggest that 18FDG-PET scanning is a useful tool in evaluation of patients with suspected metastatic plexopathy, particularly if other imaging studies are normal. It may also be useful in distinguishing between radiation-induced and metastatic plexopathy. 相似文献
994.
Srinivasula SM Ahmad M Guo Y Zhan Y Lazebnik Y Fernandes-Alnemri T Alnemri ES 《Cancer research》1999,59(5):999-1002
Alternatively spliced isoforms of certain apoptosis regulators, such as Bcl-x, Ced-4, and Ich-1, have been shown to play opposing roles in regulating apoptosis. Here, we describe the identification of an endogenous alternatively spliced isoform of caspase-9, named caspase-9b, which lacks the central large subunit caspase domain. Caspase-9b is detectable in many cell lines by PCR and at the mRNA and protein levels. Caspase-9b can interact with the caspase recruitment domain of Apaf-1, and like the active site mutant of caspase-9, it can inhibit multiple forms of apoptosis, including those triggered by oligomerization of death receptors. It can also block activation of caspase-9 and -3 by Apaf-1 in an in vitro cytochrome c-dependent caspase activation assay. These results suggest that caspase-9b functions as an endogenous apoptosis inhibitory molecule by interfering with the formation of a functional Apaf-1-caspase-9 complex. 相似文献
995.
Fatima M Ahmad I Sayeed I Athar M Raisuddin S 《Aquatic toxicology (Amsterdam, Netherlands)》2000,49(4):243-250
Pollutant-induced abnormal functioning of phagocytes and associated consequences were studied in freshwater catfish Heteropneustes fossilis (Bloch). Fish were exposed to effluent collected from bleached kraft type of paper mill at the concentration levels of 0.5, 1 and 2% for 15, 30, 60 and 90 days. Respiratory burst activity of peritoneal and head kidney phagocytes of exposed fish was measured by nitroblue tetrazolium reduction assay. Lipid peroxidation (LPO) was estimated in liver, gill and kidney of fish by measuring thiobarbituric acid reaction substances. It was observed that the phagocyte-activating xenobiotics of effluent induced an increase in the respiratory burst activity in phagocytes. The induction of respiratory burst activity was concomitantly associated with an increase in the peroxidative damage of tissues. The tissues most affected were kidney and gills. The change in LPO values in the gills of exposed fish was concentration- and time-dependent, showing significant increases (P<0.05 to <0.001) in all the exposed groups as compared with control fish. An almost similar pattern of LPO was observed in head kidney tissue (P<0.05 to <0.001). As regards liver, increase in LPO was not widespread, except at 0.5% for 90 days (P<0.05). In fact, reduced rates of LPO were observed in the livers of some groups. The results of respiratory burst corroborate with the phagocytic activation as well as with the extent of lipid peroxidation in the tissues, showing high population of circulatory phagocytes. Our results demonstrate that fish of polluted water are subjected to oxidative stress of multifarious dimensions. 相似文献
996.
Significant differences between the metabolism of retinoic acid by different tissues might be an important determinant of the effectiveness of a systemically administered inhibitor at a particular tissue site. Here the metabolism of retinoic acid has been studied in microsomal fractions from different tissues (liver, kidney, intestinal mucosa, lung, skin, brain) of the male rat to determine their relative metabolic activity. Kinetic analysis revealed major differences between the activity of different tissue microsomes. This is shown by the Vmax values for the metabolism of retinoic acid-liver (102+/-39.0 pmol (mg protein)(-1) min(-1)) was 100 times more active than the lung (1+/-0.03 pmol (mg protein)(-1) min(-1)), which was the least active. The range of Km values for microsomes from the different tissues was narrow (0.48-1.40 microM). Taking into account the mass of the tissue, the gross activity ranking for metabolism of retinoic acid was liver > skin = kidney > brain > intestinal mucosa > lung. It is concluded that metabolism of administered retinoic acid occurs mainly in the liver but that cellular retinoic acid levels in some other tissues (skin, kidney, brain) could be reduced (metabolized) to such an extent that higher levels might be observed after the use of inhibitors of retinoic acid metabolism. 相似文献
997.
Sunil N Dutt Ahmad Haider-Ali Murray Stewart Simon M C Morrissey 《Indian journal of otolaryngology and head and neck surgery》1999,51(3):16-20
There are very few indications for surgical management of chronic rhinosinusitis in children. This has been partly due to the fact that the definition of what qualifies as racalcitrant sinusitis in children is still obscure. There is also significant evidence in literature that surgery, especially radical surgery, on the nose and sinuses in children would result in some interference with the growth of the facio-maxillary skeleton. The advent of Functional Endoscopie sino-nasal Surgery ( F. E. S. S. ) in recent years has changed the philosophy of surgery for paediatric rhinosinusitis and has proven to be an effective choice of management in difficult cases. We persent here our experience and preliminary results with the use of FESS in nine children with sinonasal disorders including cystic fibrosis. The usefulness of the recently described Lund- mackay and Kennedy Scoring System for chronic rhinosinusitis in terms of symptom score, radiological score, endoscopie score and surgical score has been demonstrated. 相似文献
998.
Dr. P. Ahmad M.D. D.C.H. A. Z. Khan M.D. B. Hasan M.D. S. N. Sinha M.D. 《Indian journal of pediatrics》1982,49(5):689-693
Two hundred fifty six children in the age group of 0–5 year belonging to families registered under the Urban Health Centre were studied. An inverse relationship was observed between birth interval and prevalence of malnutrition, gastroenteritis, anemia and worm infestation. Further a positive correlation was observed between morbidity and increasing birth order more so after 3rd birth order. 相似文献
999.
We analyzed the characteristics of patients presenting with acute pancreatitis to our unit. A total of 71 patients were admitted to the Surgical Department at University Kebangsaan Malaysia (UKM) over a period of seven years, between January 1990 to December 1996 with acute pancreatitis. There was a fourfold increase in incidence of acute pancreatitis in our hospital from January 1990 to December 1996. The commonest identifiable aetiology was gallstones followed by alcohol. There were two deaths. We conclude that acute pancreatitis is increasingly being diagnosed in our local population. This may be due to either greater awareness or changes in lifestyle of the population. 相似文献
1000.
Lim TO Lim YN Wong HS Ahmad G Singam TS Morad Z Suleiman AB Rozina G Ong LM Hooi LS Shaariah W Tan CC Loo CS 《The Medical journal of Malaysia》1999,54(4):459-470
We describe the outcomes on haemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) provided by the Ministry of Health (MOH). The assessment was based on data from the Malaysian Dialysis Registry on 2480 HD and 732 CAPD patients who commenced dialysis between 1980 and 1996. Young patients (age < 40) have remarkable long term survival (life expectancies of 16 years on HD, 18 years on CAPD). Adjusting for background mortality, relative survival of older patients was as good as younger ones. Diabetics did poorly. 52% of HD and 26% of CAPD patients were employed in 1996. 71% of HD patients scored 10(normal) on QL index (a measure of quality of life) while 60% of CAPD patients have similar score. Differences in rehabilitation and QL index scores by age, gender and diabetes were also observed. Outcomes of dialysis in the MOH programme are reassuring. 相似文献