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81.
Morioka CY Saito S Machado MC Ohzawa K Kubrusly MS Cunha JE Watanabe A 《In vivo (Athens, Greece)》2004,18(2):113-117
K-ras point mutation at codon 12 has a relationship greater than 90% with pancreatic cancer. Cancer therapy should also include the treatment of metastatic disease because it is known that the properties of metastatic cells may vary considerably from those of the primary tumor. AIM: To clarify if the same drugs, which can inhibit the tumor growth in the parental cell line, can inhibit the pancreatic metastatic and remetastatic cell lines at the same concentrations and to compare the inhibition with antisense oligonucleotides mismatched to K-ras gene, in Syrian golden hamsters. MATERIALS AND METHODS: HaP-T1, a BHP-induced hamster pancreatic cancer cell line, MS-PaS-1 (a metastatic cell line established from "return trip" metastases from the liver to the pancreas) and MS-PaS-2 named as a "remetastatic cell line", i.e., metastases from MS-PaS-1 were used. MTT and MTT-agarose assays were performed, using 5-Fluorouracil (5-FU), Mitomycin C (MMC) and antisense oligonucleotide specific to K-ras oncogene. RESULTS: The inhibitory concentration (IC50) of 5-FU, which inhibited HaP-T1, had to be increased by 50-fold to inhibit MS-PaS-1 and 100-fold to inhibit MS-PaS-2. MMC had to be increased by 10-fold to inhibit MS-PaS-1 and 50-fold to inhibit MS-PaS-2. However, IC50 was the same when antisense oligonucleotide was tried in these 3 cell lines. CONCLUSION: Antisense oligonucleotide-targeted K-ras gene may be a good choice for therapy because it could inhibit the growth in metastatic and remetastatic cells as well as in primary tumor cells. 相似文献
82.
Obective: This study was conducted as part of a course on Human Sexuarity and Adodescence for school childrenmèt/ to ascertain the prior knowledge of children, source of their knowledge and whether the course was a felt need of the childrenMethod : Students were given a questionnaire before the course. Few selected questions were asked again after the last session.
The course was conducted in a private co-educational. English medium school in urban Bangalore involving 392 students 13–15
years of age. The course was designed by the authors and dealt with anatomy, physiology, social and psychological aspects
of growing up, HIV and contraception.Results : 55–70% of class VIII; IX and X students had learnt about sex from friends, 30% from movies, 15% from text books and only
10% from parents. Misconceptions about anatomy, childbirth, HIV were common. 90% of tenth class students felt that education
in human sexuality was necessary.Conclusion: In spite of chapters on reproduction in textbooks, children turn to peers or media to gather information on sexuality. Education
in human sexuality is nequired in our schools, as this need is currently not being addressed adequately in our society. 相似文献
83.
Grönefeld GC Israel CW Padmanabhan V Koehler J Cuijpers A Hohnloser SH;WorldWide Gem DR Study Group 《Pacing and clinical electrophysiology : PACE》2002,25(12):1708-1714
Reviews of stored electrograms from ICDs revealed a 5-30% incidence of short-long-short intervals preceding the onset of recurrent ventricular tachyarrhythmias. Rate stabilization by dedicated antibradycardia pacing algorithms has, therefore, been suggested to prevent onset of pause dependent tachyarrhythmias. However, the clinical efficacy of this approach has not been studied systematically. In a prospective multicenter crossover study, patients were randomized to activation or deactivation of an implemented ventricular rate stabilization algorithm (VRS) after first implant of a dual chamber ICD. After 3 months, all patients were crossed over to the alternate programming. The rate of appropriate spontaneous VA episodes was compared between VRS On and VRS Off. Stored electrograms were reviewed for evaluation of the mode of onset of tachyarrhythmias. Overall efficacy analysis was based on 309 patients enrolled in the study. Forty percent (124/309) of the patients experienced 4,973 VA episodes. Based on an intention-to-treat analysis, VRS Off and On arrhythmia incidence was 10.2 and 6.6 normalized to 3 months, respectively (risk reduction 35%; P = 0.18) On an on-treatment basis, a reduction from 9.0 episodes to 8.1 episodes (10% risk reduction, P = 0.24) was seen. In an extended Cox model adjusting for confounding variables, the relative risk for recurrent episodes was 0.92 during VRS On compared to Off (95% CI: 0.58-1.48; P = 0.74). During VRS Off, pause dependent onset was documented in only 36 (8%) of 427 visually analyzed episodes. There was no significant reduction in the incidence of recurrent ventricular tachyarrhythmias with VRS On compared to the Off programming in this prospective study. 相似文献
84.
Sargento L Saldanha C Monteiro J Perdigão C Martins e Silva J 《Thrombosis and haemostasis》2003,89(5):892-903
Haemostatic, hemorheologic and inflammatory disturbances have been associated with acute coronary syndromes. Most knowledge is reported in cross sectional studies and are without time dependent evolution of these profiles. The aim of this study was to evaluate, during the first year, the evolution of the haemostatic, hemorheologic and inflammatory profiles determined at hospital discharge in survivors with transmural myocardial infarction (MI). Eighty eight (79 male; 9 female) mean age of 58 +/- 11 years, survivors of a transmural MI were prospectively studied at discharge, 6 months and one year after the event. Haemostatic (protein C, antithrombin III and plasminogen activator inhibitor 1), hemorheologic (blood fluidity and components) and inflammatory profiles (polymorphonuclear elastase and leukocyte count) were determined using standard methodology. The results of the study can be summarized as follows: (1) Protein C decreased (p < 0.05) over time while PAI-1 only varied significantly until 6(th) month. (2) Plasma viscosity and fibrinogen (p < 0.001) decrease over time, while erythrocyte aggregation (p < 0.001) and haematocrit increased. Whole blood viscosity did not vary. (3) Leukocyte decreased (p < 0.001) and elastase did not (4). Those patients with cardiovascular events (n = 7) had higher PAI-1 concentration (p < 0.05) and leukocyte count (p < 0.01), at discharge (5) Left ventricle ejection fraction correlated significantly with plasma viscosity (r = 0.35 p < 0.05). The results of this longitudinal study show dynamic modifications of the haemostatic, hemorheologic and inflammatory profiles during the first year of a transmural myocardial infarction. In addition, there are interrelations between them and the clinical profile that could help to explain the clinical evolution of this group of patients. 相似文献
85.
Intrauterine transmission of cytomegalovirus to infants of women with preconceptional immunity 总被引:1,自引:0,他引:1
Prema Saldanha Sonika Dahiya Radha R. Pai Urmila N. Khadilkar 《Indian journal of pediatrics》2001,68(8):770-770
Current Literature
Gene therapy for hemophilia 相似文献86.
Gattás GJ Cardoso Lde A Medrado-Faria Mde A Saldanha PH 《Occupational medicine (Oxford, England)》2001,51(2):107-113
Methanol has been proposed in different countries as an alternative automotive fuel to be used as an additive to, or replacement for, gasoline or ethanol. Utilization of methanol is increasing exposure to low levels of methanol vapors in the environment and more specifically in occupational settings such as gas stations. Pump operators are exposed to relatively high levels of fuel vapors, the consequences of which have not been fully examined. In this study, the micronucleus assay in squamous oral cells was performed on pump operators of 28 gas stations in three different periods in the city of S?o Paulo, Brazil. The frequency of micronuclei (MN) was evaluated before and 1 year after a mixed fuel called MEG, which contains 33% methanol, 60% ethanol and 7% gasoline, was introduced. The third evaluation, 3 years later, represents a period where the number of cars using alcohol fuel had decreased drastically and the pump operator exposure to MEG became very low. The frequency of MN observed in 76 employees in 1992 (mean = 3.62 +/- 0.39) was significantly increased (P < 0.001) as compared with 76 operators exposed in 1989 (mean = 1.41 +/- 0.26) and 129 exposed in 1995 (mean = 1.20 +/- 0.15). These differences were also significant when compared with control groups not exposed professionally to motor fuel. These findings could indicate a mutagenic hazard of the MEG occurring in those with occupational exposure. 相似文献
87.
Jill R Stewart Rebecca J Gast Roger S Fujioka Helena M Solo-Gabriele J Scott Meschke Linda A Amaral-Zettler Erika del Castillo Martin F Polz Tracy K Collier Mark S Strom Christopher D Sinigalliano Peter DR Moeller A Fredrick Holland 《Environmental health : a global access science source》2008,7(Z2):S3
Innovative research relating oceans and human health is advancing our understanding of disease-causing organisms in coastal ecosystems. Novel techniques are elucidating the loading, transport and fate of pathogens in coastal ecosystems, and identifying sources of contamination. This research is facilitating improved risk assessments for seafood consumers and those who use the oceans for recreation. A number of challenges still remain and define future directions of research and public policy. Sample processing and molecular detection techniques need to be advanced to allow rapid and specific identification of microbes of public health concern from complex environmental samples. Water quality standards need to be updated to more accurately reflect health risks and to provide managers with improved tools for decision-making. Greater discrimination of virulent versus harmless microbes is needed to identify environmental reservoirs of pathogens and factors leading to human infections. Investigations must include examination of microbial community dynamics that may be important from a human health perspective. Further research is needed to evaluate the ecology of non-enteric water-transmitted diseases. Sentinels should also be established and monitored, providing early warning of dangers to ecosystem health. Taken together, this effort will provide more reliable information about public health risks associated with beaches and seafood consumption, and how human activities can affect their exposure to disease-causing organisms from the oceans. 相似文献
88.
Prevalence of risk factors for cardiovascular disease in Canadians 55 to 74 years of age: results from the Canadian Heart Health Surveys, 1986-1992 总被引:1,自引:1,他引:0 下载免费PDF全文
DB Langille MR Joffres KM MacPherson P Andreou SA Kirkland DR MacLean 《Canadian Medical Association journal》1999,161(8):S3-S9
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification. 相似文献
89.
90.
Chest computed tomography (CT), including high-resolution CT with thin (1.5-mm) sections was used to evaluate proved (pathologically or clinically) lymphangitic spread (LS) of tumor in 12 patients. These appearances were compared with thin-section scans obtained in 11 healthy subjects. Thin-section CT demonstrated findings consistent with thickening of the normal lung interstitium. In all patients, thin sections showed an increase in the number of peripheral lines (1-2 cm in length) that were diffuse in generalized disease and localized in focal disease. Normal peripheral arcades were not increased in number, but the limbs forming the arcades were thickened in all patients. A diffuse increase in linear and curvilinear structures (reticular pattern) was seen toward the center of the lung. Polygonal structures 1-2 cm in diameter were seen in seven patients with LS but not in healthy subjects. Fissures were thickened in nine patients. Selected 1.5-mm-thick CT sections are recommended through abnormal areas (seen at CT or on chest radiographs) or if these are normal at three levels (midapex, hilus, and 3 cm above the diaphragm) when scanning patients with tumors known to cause LS. 相似文献