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971.
Carlos Lazaro Jose M Benitez-del-Castillo Alfredo Castillo Julian Garcia-Feijoo Juana M Macias Julian Garcia-Sanchez 《Ophthalmology》2002,109(1):76-79
OBJECTIVE: To evaluate the loss of lens transparency incurred by patients undergoing trabeculectomy. DESIGN: A prospective cohort study. PARTICIPANTS AND CONTROLS: Data corresponding to 33 eyes of 33 consecutive patients with primary open-angle glaucoma (POAG) subjected to trabeculectomy (group 1) were compared with those corresponding to 12 eyes of 12 patients with POAG receiving topical antiglaucomatous treatment (group 2). INTERVENTION: Lens fluorophotometry was performed on the group 1 patients before and 12 months after surgery. In group 2, fluorophotometry was conducted at the onset of the study and at 12 months of follow-up. MAIN OUTCOME MEASURES: Starting and final lens autofluorescence and transmittance values corresponding to each subject group were compared. RESULTS: In group 1, starting and final autofluorescence was 556.3 +/- 184.3 and 691.1 +/- 179.3 Eq ng/ml, and starting and final transmittance was 0.78 +/- 0.11 and 0.67 +/- 0.14, respectively. Respective values for group 2 were 574.3 +/- 94.8 and 595.2 +/- 107.0 Eq ng/ml and 0.72 +/- 0.17 and 0.71 +/- 0.16. The mean change between final and initial autofluorescence was statistically different between groups (134.7 +/- 123.7, group 1, 20.9 +/- 25.1 Eq ng/ml, group 2; P < 0.001). Similarly, a significant difference (P < 0.001) in transmittance change was observed between the surgery and control groups (-0.11 +/- 0.072, group 1; 0.02 +/- 0.008, group 2) CONCLUSIONS: It was demonstrated by lens fluorophotometry that trabeculectomy in POAG leads to a loss in lens transparency. 相似文献
972.
973.
A comparative study of two different doses of cytarabine for acute myeloid leukemia: a phase III trial of Cancer and Leukemia Group B. 总被引:3,自引:1,他引:2
R O Dillman R B Davis M R Green R B Weiss A J Gottlieb S Caplan S Kopel H Preisler O R McIntyre C Schiffer 《Blood》1991,78(10):2520-2526
Between 1982 and 1986, 326 evaluable patients with acute myeloid leukemia (AML) were randomized to receive cytarabine (Ara-C) at 200 mg/m2 (A200) or 100 mg/m2 (A100) for induction and maintenance therapy. Cycle 1 of induction therapy consisted of 7 days of continuous intravenous (IV) Ara-C and 3 days of i.v. daunorubicin (DNR); cycle 2, if needed, consisted of 5 days of Ara-C and 2 days of DNR. Complete responders (CR) then received monthly subcutaneous (SC) Ara-C at the respective doses (A100 or A200) with 6-thioquanine (6TG) at months 1 and 5, with vincristine (VCR) and prednisone at months 2, 4, 6, and 8, and with DNR at months 3 and 7. Complete response rates were 58% (A100) and 64% (A200) (P = .29). Median survival was 46 weeks (A100) and 38 weeks (A200) (P = .64); 5-year survival was 10% (A200) and 8% (A100). Median time to remission was 6.7 weeks (A200) and 8.1 weeks (A100) (P = .18). Median disease-free survival was 41 weeks (A200) and 44 weeks (A100) (P = .86). Deaths were attributed to therapy-related toxicities in 21% (A200) and 13% (A100) (P = .05). The 5-year survival was 15% for patients with performance status (PS) 0, 8% for PS 1 to 2, and 2% for PS 3 to 4, 18% for patients less than 40 years, 8% for ages 40 to 59, and 3% for age 60 or greater. Stratification of data by age and PS suggested that A200 may improve survival in patients less than 60 years with a good PS 0 (P = .05). This trial does not support the superiority of A200 over A100 in the treatment of AML. 相似文献
974.
Stephen P. Schiffer 《Breast cancer research and treatment》1997,46(2-3):313-331
The use of animals in cancer research continues to be important for the study of tumor biology, the development and testing of new therapies, and risk assessment. The new knowledge generated from this research contributes to the health and welfare not only of human beings, but also of animals which develop cancer. However, the use of animals for cancer research is a privilege which carries with it scientific, professional, and moral obligations. The three tenets of a sound animal research program include good science, humane care, and regulatory compliance. Recognizing the complex interactions in the tumor-animal model, the investigator needs to address a wide range of issues during experimental design and implementation including animal welfare concerns, complicating factors in colony management, and compliance with laws, regulations, and policies. Therefore, both practical and philosophical considerations enjoin researchers to maintain the highest standards of animal care. 相似文献
975.
D. Schiffer P. Cavalla A. Migheli M. T. Giordana L. Chiadò-Piat 《Journal of neuro-oncology》1996,27(2):101-109
Summary
Bcl-2proto-oncogene prevents apoptosis in many conditions. First detected in lymphomas, it has been also described in non-lymphoid tissues. The immunohistochemical distribution of bcl-2 protein in 100 neuroepithelial tumors is presented. Bcl-2 was positive in some neurons of normal nervous tissue, in reactive astrocytes and variably in all neuroepitelial tumors. The reaction product was either diffuse or granular, due to bcl-2 protein localization on cytoplasmic, nuclear and mitochondrial membranes. The positivity was high in medulloblastomas and in astrocytic tumors. In the latter, the strongest staining was found in cells retaining the astrocytic aspect. Oligodendroglial cells were minimally stained.No correlation of bcl-2 staining with survival was found in each tumor type. The interpretation of the results is based on the one side on the constitutive role played by bcl-2 in the nervous tissue and its neoplastic derivatives. On the other side, in tumors bcl-2 acts by preventing tumor cells from undergoing apoptosis. Bcl-2 expression in brain tumors, therefore, receives a dual interpretation. For this reason and for the lacking of correlation with survival, bcl-2 expression cannot be regarded as a prognostic factor. 相似文献
976.
A case of sacrococcygeal teratoma with unusually high intraspinal extension is reported and the symptomatology and treatment are discussed. A 7-month-old male presented at birth with a prominent mass of the right gluteal region preventing him from straightening his legs and causing undue effort during defecation. Magnetic resonance T1-weighted imaging revealed a thoracolumbosacrococcygeal, partly cystic tumor with intraspinal extension up to the mid-thoracic spine. During two-staged surgery, a cystic tumor containing fragments of hair, teeth, and bone and adherent to its surroundings was completely removed. The histologic examination confirmed the presence of a benign teratoma. A neurogenic bladder of the lower-motor-neuron type and constipation improved spontaneously. No further neurological deficits before and during a 3-year postoperative follow-up period were recorded. 相似文献
977.
978.
Sagrario Martín-Aragón Belén Basabe Juana M. Benedí Angel M. Villar 《Pharmaceutical biology》2013,51(2):109-113
In vitro and in vivo antioxidant properties of an anthocyanoside complex extract from Vaccinium myrtillus (AVM) were evaluated. This extract scavenged super-oxide anion in the hypoxanthine-xanthine oxidase system and inhibited CCl 4 -NADPH-stimulated lipid peroxidation in microsomes. It was found that pre-treatment of mice with 250 and 500 mg/kg oral dosages, respectively, of AVM inhibited significantly liver lipid peroxidation stimulated by FeCl 2 -ascorbic acid-ADP mixture. These results suggest that AVM might be useful as a liver protective agent and in the prevention of other diseases caused by oxidative stress. 相似文献
979.
Carlos Salgado Garcia Amelia Jimenez Heffernan Elena Sanchez de Mora Carlos Ramos Font Juana Lopez Martin Francisco Rivera de los Santos Ignacio Ynfante Milá 《European journal of nuclear medicine and molecular imaging》2014,41(1):119-125
Purpose
To compare the safety of regadenoson, a selective agonist of A2A adenosine receptors, combined with low-level exercise, between subjects with mild/moderate chronic obstructive pulmonary disease (COPD) and asthma referred for myocardial perfusion imaging (MPI).Methods
We studied 116 patients, of whom 67 had COPD and 49 asthma (62 % men, mean age 68.3?±?11.3 years, range 31 – 87 years). Patient demographics, past medical history, medications, clinical symptoms during stress and changes in blood pressure (BP) and heart rate (HR) were evaluated.Results
Both groups were comparable with regard to hypertension, dyslipidaemia, diabetes and medications with the exception of a higher rate of use of anticholinergics in patients with COPD and of antileukotrienes in asthmatics (58.2 % vs. 28.6 % and 1.5 % vs. 14.3 %, respectively; all p?<?0.01). There was a higher incidence of dyspnoea in COPD patients and of headache and feeling hot in asthmatic patients (40.3 % vs. 22.4 %, 6 % vs. 18.4 % and 10.4 % vs. 26.5 %, respectively; all p?<?0.05). Although there was no difference in the incidence of other adverse events, we observed a higher frequency in asthmatics of flushing, dry mouth, sweating and fatigue (1.5 % vs. 6.1 %, 14.9 % vs. 24.5 %, 0 % vs. 4.1 % and 37.3 % vs. 49 %, respectively). Adverse events were self-limiting, except in three patients who suffered persistent dyspnoea (2 of 67 COPD patients; 1 of 49 asthma patients) requiring theophylline administration. We observed no significant changes in BP among either group, but there was a tendency towards a higher increase in systolic BP in COPD patients following regadenoson administration (148.3 ±?27.6 vs. 154.6 ±?31.0 mmHg, p?=?0.056).Conclusion
This study showed a good safety profile in our series of COPD and asthma patients undergoing MPI. Regadenoson was well tolerated by all patients, with dyspnoea, headache and feeling hot showing differences between groups. 相似文献980.
Randolph B. Schiffer Michael P. McDermott Catherine Copley 《Archives of environmental & occupational health》2013,68(5):389-395
The authors investigated a reported incidence cluster of multiple sclerosis (MS) cases in a small, north-central Illinois community to determine validity and statistical significance. DePue, Illinois–a small, north-central Illinois community–has previously been the site of significant environmental heavy-metal exposure from a zinc smelter. Significant contamination of soil and water with zinc and other metals has been documented in this community during the time period of interest. In the mid-1990s, several cases of MS were reported to the Illinois Department of Public Health within the geographic limits of this community. Available medical records from purported MS cases reported to the Illinois Department of Public Health were reviewed, and living individuals were seen and examined. Statistical analyses were conducted with clinically definite MS cases; onset dates were determined by first symptom, and expected incidence rates were determined from published epidemiologic studies. Nine new cases of clinically definite MS occurred among residents of DePue, Illinois, during the period between 1971 and 1990. Seven of the 8 living subjects included in the final analyses were examined by one author (RS). The computed incidence rate deriving from these cases within DePue Township, Illinois, represented a statistically significant excess of new MS cases over expected. During the period from 1971 through 1990, a significant excess of MS cases occurred within the population of DePue, Illinois. Significant exposure of this population to mitogenic trace metals, including zinc, was also documented during this time period. 相似文献