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101.
PURPOSE/BACKGROUND: Penetrating keratoplasty is the logical solution for the management of corneal opacities. In situations such as in Papua New Guinea, where donor corneal tissue is scarce and corneal opacities are plenty, an alternative procedure for the management of corneal opacities in the form of ipsilateral rotational autokeratoplasty was considered. METHODS: In the present prospective study, ipsilateral rotational autokeratoplasty was performed in 17 eyes over a 2 year period in a general hospital.The patient's cornea was trephined eccentrically and the corneal opacity was dialed out of the visual axis and was replaced by clear peripheral cornea. RESULTS: Most opacities were leucomata (76.4%). The average size of the opacity was 5.1 mm and the corneal button size was 7 mm.A final visual acuity of 6/18 or better was obtained in 64.7% of cases (at 12 months). No significant postoperative complications were encountered. No complex formula was needed to calculate the size of the button and, by simply adding 3 mm to the pupillary diameter in standard illumination, one could make an estimation of the graft diameter. CONCLUSIONS: Rotational autokeratoplasty has a definite role in places where donor corneal tissue is scarce, in patients in whom long-term steroids are a risk or in situations where follow up of patients is difficult. Rejection is a theoretical impossibility, but late endothelial failure could occur, requiring regrafting. Rotational autokeratoplasty should be seriously considered as an alternative to conventional penetrating keratoplasty. 相似文献
102.
P3 component of the endogenous cerebral evoked response is a sophisticated, objective and quantitative approach to assess higher functions of the brain. This test was employed using auditory 'odd ball' paradigm to assess cognitive functions in thirty non insulin dependent diabetic patients (NIDDM) aged 43.6 +/- 9 yrs with poor blood glucose control. (HbAlc. 9.9 +/- 1.0%). The peak latencies of N2, P3 components of event related evoked potentials obtained in these patients were compared with 30 age and sex matched non diabetic healthy controls. Latencies of these potentials were: N2 = 248.0 +/- 36.3, P3 = 391.6 +/- 49.9 msec in NIDDM as compared to 220.6 +/- 26.4, 326.2 +/- 26.8 msec in controls and were highly significant (P < 0.001). The duration of disease, blood glucose level or the physical parameters of height, weight and blood pressure did not show any correlation with N2 or P3 latencies or amplitude. These findings provide an electrophysiological evidence of delayed cognition in poorly controlled NIDDM cases. 相似文献
103.
Didemnin B (NSC-325319), a new depsipeptide isolated from a Caribbean tunicate, has been evaluated in a clinical phase I study. The drug was administered in a schedule of a 4 weekly intravenous injection in a six-weeks cycle. Fifty-three patients received 71 evaluable cycles in an escalated dose ranging from 0.4 mg/m2/week to 2.5 mg/m2/week. No hematological toxicity was demonstrated at any dose level. Without prophylactic antiemetics nausea and vomiting was dose limiting at 1.2 mg/m2/week. Due to the use of Cremophor EL as a solvent, hypersensitivity reactions occurred in 9 patients. These reactions occurred following prior exposure to the drug and were commonly seen at the 3rd dose. They were not dose related but became more frequent at 1.5 mg/m2/week necessitating prophylactic treatment with H1 and H2 receptor blocking agents. Non-hematological toxicities included mild diarrhea, mucositis, anorexia, headaches, and local phlebitis. The dose- limiting toxicity was generalized weakness which became severe and disabling in 3 of 6 patients treated at 2.5 mg/m2/week. No objective responses were documented in 39 patients with evaluable disease. The recommended dose for phase II studies was 2.3 mg/m2/week × 4 4 in a 6-weeks cycle given with prophylactic antiemetics and H1 and H2 receptor blocking agents. 相似文献
104.
Dhar S Jain S Verma G Tanwar RK 《Indian journal of dermatology, venereology and leprology》1996,62(5):331-332
A case of disseminated molluscum contagiosum (MC) has been reported in a patient suffering from AIDS. Most of the lesions were erythematous papules and nodules with central unbilication. A few giant lesions and lesions over genitalia were also observed. 相似文献
105.
A plant of Artemisia annua containing high amounts of artemisinic acid (0.8%) was isolated. the combined concentration of the sesquiterpene artemisinin, and its intermediates artemisinic acid and artemisinin-b in this plant was 1.35%. the plant has been cloned by micropropagation in tissue culture. 相似文献
106.
The effects of dose and duration of treatment with the potenttumor-promoting agent 12-O-tetra-decanoylphorbol-13-acetate(TPA) on the formation of skin tumors in Charles River CD-1mice was studied. Mice were initiated with a single applicationof 0.2 µmol of 7, 12-dimethylbenz[a]anthracene (DMBA)in 0.2 ml acetone. Beginning two weeks after initiation, micewere treated twice weekly with various doses (0.01 20nmol) of TPA in 0.2ml acetone. Application of either 0.01 or0.1 nmol of TPA did not elcity tumors during the 50 weeks durationof treatment. A dose-dependent increase in the number of papillomaswas observed through the range of 1 to 10 nmol of TPA. Twiceweekly applications of 20nmol of TPA did not further enhancethe papilloma incidence. A good correlation was observed betweenthe induction of ornithine decarboxylase (ODC) activity andthe formation of skin tumors by various doses of TPA. To determine the effect of promotion duration on the incidenceof papillomas and carcinomas, mice were treated with 10 nmolof TPA for various durations (6,12,18,24,30, or 36 weeks) beginning2 weeks after initiation with 0.2 µmol of DMBA. Mice promotedfor only 6 weeks developed papilllomas and carcinomas afterpromotion had been discontinued. There was an intermediate incidenceof tumors in the group treated for 12 weeks. Promotion for 18,24, 30, or 36 weeks elicited virtually identical yields of papillomas.The incidence of carcinomas was proportional to promotion durationtimes of 6, 12, and 18 weeks, but carcinoma incidence was lessthan maximal in mice promoted for 24 weeks or longer. The results indicate that a) the incidence of papillomas servesas a rapid (18 weeks) index for subsequent appearance of carcinomas,b) twice weekly applications of 10 nmol of TPA for 18 weeksfollowing initiation of female CD-1 mice with 0.2 µmnolof DMBA is an appropriate protocol for maximum tumor yield ininitiation-promotion experiments, and c) ODC induction may bean important component of the mechanism of skin tumor promotionby TPA. 相似文献
107.
Sachar RK Singh WP Verma J Gill PJ Sehgal R Singh H Soni RK 《Indian journal of maternal and child health : official publication of Indian Maternal and Child Health Association,》1991,2(3):79-81
In India, interviews were conducted with 250 couples who had at least 2 living children and at least 1 son so researchers could examine the effect of child loss on contraceptive usage. The interviewees lived in the area served by the rural health center in Pohir. 67 couples had lost a child. The child loss group had an acceptance rate for contraception of 41.7% compared to 44.8% for the group who had not experienced child loss. The difference was insignificant. Caste, literacy, and parity did not affect contraceptive usage. These findings suggest that child loss does not play a crucial role in contraception acceptance. On the other hand, some studies show that it is a barrier to fertility limitation. Additional studies are needed to resolve the issue of child loss and fertility. 相似文献
108.
Dietary carotenoids and risk of lung cancer in a pooled analysis of seven cohort studies. 总被引:5,自引:0,他引:5
Satu M?nnist? Stephanie A Smith-Warner Donna Spiegelman Demetrius Albanes Kristin Anderson Piet A van den Brandt James R Cerhan Graham Colditz Diane Feskanich Jo L Freudenheim Edward Giovannucci R Alexandra Goldbohm Saxon Graham Anthony B Miller Thomas E Rohan Jarmo Virtamo Walter C Willett David J Hunter 《Cancer epidemiology, biomarkers & prevention》2004,13(1):40-48
Intervention trials with supplemental beta-carotene have observed either no effect or a harmful effect on lung cancer risk. Because food composition databases for specific carotenoids have only become available recently, epidemiological evidence relating usual dietary levels of these carotenoids with lung cancer risk is limited. We analyzed the association between lung cancer risk and intakes of specific carotenoids using the primary data from seven cohort studies in North America and Europe. Carotenoid intakes were estimated from dietary questionnaires administered at baseline in each study. We calculated study-specific multivariate relative risks (RRs) and combined these using a random-effects model. The multivariate models included smoking history and other potential risk factors. During follow-up of up to 7-16 years across studies, 3,155 incident lung cancer cases were diagnosed among 399,765 participants. beta-Carotene intake was not associated with lung cancer risk (pooled multivariate RR = 0.98; 95% confidence interval, 0.87-1.11; highest versus lowest quintile). The RRs for alpha-carotene, lutein/zeaxanthin, and lycopene were also close to unity. beta-Cryptoxanthin intake was inversely associated with lung cancer risk (RR = 0.76; 95% confidence interval, 0.67-0.86; highest versus lowest quintile). These results did not change after adjustment for intakes of vitamin C (with or without supplements), folate (with or without supplements), and other carotenoids and multivitamin use. The associations generally were similar among never, past, or current smokers and by histological type. Although smoking is the strongest risk factor for lung cancer, greater intake of foods high in beta-cryptoxanthin, such as citrus fruit, may modestly lower the risk. 相似文献
109.
110.
Identification and validation of genes involved in the pathogenesis of colorectal cancer using cDNA microarrays and RNA interference. 总被引:47,自引:0,他引:47
Noelle Sevilir Williams Richard B Gaynor Shane Scoggin Udit Verma Tunc Gokaslan Clifford Simmang Jason Fleming Denise Tavana Eugene Frenkel Carlos Becerra 《Clinical cancer research》2003,9(3):931-946
PURPOSE: The purpose of this study was to profile gene expression changes in colorectal tumors to identify new targets and strategies for the management of this disease. EXPERIMENTAL DESIGN: cDNA microarray analysis was used to detect differences in gene expression between normal tissue and colon tumors and polyps isolated from 20 patients. To identify genes that are important in regulating the growth properties of colorectal cancer, RNA interference (RNAi) was used to disrupt expression of several of the overexpressed genes in a colon tumor cell line, HCT116, which showed similar patterns of gene expression as many of the patient tumors. RESULTS: Expression changes of > or =2-fold in approximately one-third of the patients were consistently observed for 2632 of a total of 9592 genes (574 up-regulated genes and 2058 down-regulated genes). Subsequent analysis of 13 genes by quantitative real-time PCR confirmed the reliability of this analysis. RNAi-mediated disruption of the expression of one of these genes, survivin, a potent inhibitor of apoptosis, severely reduced tumor growth both in vitro and in an in vivo xenograft model. CONCLUSIONS: The combined use of microarray analysis and RNAi provides an excellent system to define the role of specific genes that are up-regulated in cancer lead to the increased in vitro and in vivo growth of colon tumors. 相似文献