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101.
To evaluate the effectiveness of a cytological screening to prevent invasive cervical cancer in the province of Trento, a northern Italian area where a population-based cancer registry is active. The history of Pap test was evaluated through a case-control study in 61 population-based invasive cervical cancer patients, incident during 1995-2000, and in 244 age-matched (between 25 and 75 years old) controls. Women who had at least one Pap test had a reduced risk of invasive carcinoma of 80% (odds ratio=0.20; 95% confidence intervals 0.10-0.40). The protection of a previous Pap test for both squamous cell carcinoma (odds ratio=0.23; 95% confidence intervals 0.09-0.58) and adenocarcinoma (odds ratio=0.24; 95% confidence intervals 0.07-0.78) was similar. The overall protective effect of the Pap test was not seen among younger women (<40 years). The protective effect of the Pap test seems to be stronger for shorter intervals. Our study confirms that Pap-test screening, particularly in middle-aged and older women, is an effective public health intervention with encouraging results also for the prevention of cervical adenocarcinoma.  相似文献   
102.
Integrin α6β4 is mostly expressed in epithelial tissues and endothelial and Schwann cells. Expression of α6β4 is increased in many epithelial tumours, implicating its involvement in tumour malignancy. Moreover, this integrin activates several key signalling molecules in carcinoma cells, but its ability to activate the phosphatidylinositol 3-kinase/Akt pathway is among the mechanisms by which α6β4 integrin regulates tumour behaviour. In this review we discuss the biological and clinical features of α6β4 integrin that allow it to promote tumour survival and progression of mammary tumours.  相似文献   
103.
Transbuccal drug delivery has got several well-known advantages especially with respect to peroral way. Since a major limitation in buccal drug delivery could be the low permeability of the epithelium, the aptitude of NLX to penetrate the mucosal barrier was assessed. Ex vivo permeation across porcine buccal mucosa 800 microm thick was investigated using Franz type diffusion cells and compared with in vitro data previously obtained by reconstituted human oral epithelium 100 microm thick. Both fluxes (Js) and permeability coefficients (K(p)) are in accordance, using either buffer solution simulating saliva or natural human saliva. Permeation was evaluated also in presence of chemical enhancers or iontophoresis. No significant differences in penetration rate were observed using chemical enhancers; in contrast, Js and K(p) were extensively affected by application of electric fields. Tablets, designed for Naltrexone hydrochloride (NLX) administration on buccal mucosa, were developed and prepared by direct compression of drug loaded (56%) poly-octylcyanocrylate (poly-OCA) matrices. NLX is slowly discharged from buccal tablets following Higuchian kinetic. Histologically, no signs of flogosis ascribable to NLX and/or poly-OCA were observed, while cytoarchitectural changes due to iontophoresis were detected. Buccal tablets containing NLX may represent a potential alternative dosage form in addiction management.  相似文献   
104.
A butyric acid pro-drug, pivaloyioxymethyl butyrate, AN-9, developed in our laboratory, was previously shown to act as a differentiation-inducing and an anti-cancer agent. In this study we have shown that both AN-9 and butyric acid caused a transient hyperacetylation of histones, which returned to basal levels after 6 and 12 hr, respectively. This activity precedes the induction of differentiation elicited by both agents. AN-9 induced acetylation of histones at a concentration one order of magnitude lower than butyric acid. Pre-treatment of the cells with esterase(s) inhibitors diminished the ability of AN-9 to inhibit proliferation and induce differentiation. The above suggests that the intracellular release of butyric acid fragment, from the pro-drug, is catalyzed by cellular esterase(s).  相似文献   
105.
Hepatitis A is usually a mild self-limiting infection of the liver. Nonfulminant acute renal failure very rarely complicates type A viral hepatitis. An unusual case, a 32-year-old female with serologically proven acute hepatitis A infection, was complicated by acute renal failure and the patient in this study is the first case associated with Cushing's disease. She recovered, and the laboratory tests returned normal one month after initial hospitalization. Although the mechanism responsible for renal failure in acute hepatitis A virus infection is still uncertain, possible causes are discussed with the review of literature.  相似文献   
106.
The contribution of an entero-salivary recirculation (salivary secretion-swallowed-reabsorption of drug from the gastrointestinal tract) to the values of the pharmacokinetic parameters of paracetamol was studied in a two-way crossover design. Five healthy volunteers took a tablet of Paracetamol (500 mg) in two occasions separated by a washout period. The difference between the two treatments consisted of saliva that was allowed or not to be swallowed during the 4 h of study. No statistically significant differences were found in the values of the pharmacokinetic parameters between treatments. The half-life time calculated from salivary levels was similar to the values previously reported by other authors. The percent of the oral dose excreted in saliva during 4 h of study was very low (0.1%). Secondary peaks appeared in 8 of 10 profiles. The lack of influence of salivary secretion on the pharmacokinetic parameters of Paracetamol and the low percent secreted in this fluid suggests that entero-salivary recirculation is a possible physiological phenomenon undergoing after oral administration, but it is not one of the principal phenomenon that defines the pharmacokinetic of the drug. We confirm that working with salivary samples in pharmacokinetic studies of paracetamol is a useful tool.  相似文献   
107.
The purpose of this study was to evaluate the prevalence of chronic health conditions in the Russian population who immigrated to Israel during 1989–1992. Interviewer-supported self-administered questionnaires were distributed to a 50% random sample of 1710 immigrants residing in the city of Nazareth-Ilit in Northern Israel. The final study group included 897 adults after a 3.5% of noncompliance. The study participants were asked to report all chronic diseases from a list of 11 disease states. The data were coupled with their demographic data and are presented as age/sex-specific prevalence rates. Self-reported disease prevalence rates among the Russian immigrants to Israel were found to be very high (62.2% of the males and 68.7% of the females reported a mean 3–3.5 diseases per person). These reported rates were significantly higher for immigrants from the European republics (67.1%) than for those from Asian republics (55.6%). The highest reported age-specific disease prevalence rates were for musculoskeletal diseases (389/1000), ischemic heart disease (340/1000), gastrointestinal diseases (269/1000), and hypertension (226/1000). A higher rate among females was found for almost all disease states. The prevalence rates reported by the Russian Jews in this study are much higher than commonly observed in Western countries. This is in accordance with a similar difference in reported mortality rates between Western countries and the former USSR. The etiologic explanation of this finding is yet to be studied. In addition, and in light of the mass immigration of Eastern European residents to the West it is of major importance for local health authorities to respond appropriately to the differences in health status of these immigrating populations.  相似文献   
108.
109.
OBJECTIVE: This longitudinal study had three aims: 1) determine the extent to which boys at high average risk and low average risk for substance use disorder differ on a construct of neurobehavioral disinhibition, 2) evaluate the capacity of neurobehavioral disinhibition to predict substance use frequency at age 16, and 3) demonstrate the utility of neurobehavioral disinhibition in predicting substance use disorder. METHOD: The authors derived an index of neurobehavioral disinhibition from measures of affect, behavior, and cognition. The neurobehavioral disinhibition score was used to discriminate youth at high and low average risk for substance use disorder and to predict substance use frequency after 4-6 years and substance use disorder after 7-9 years. RESULTS: The neurobehavioral disorder score significantly discriminated boys at high average risk from those at low average risk at ages 10-12. Neurobehavioral disinhibition at age 16, in conjunction with substance use frequency and risk status group, predicted substance use disorder at age 19 with 85% accuracy and accounted for 50% of the variance in Drug Use Screening Inventory overall problem density score. Neurobehavioral disinhibition was a stronger predictor of substance use disorder (odds ratio=6.83) than substance consumption frequency (odds ratio=3.19). CONCLUSIONS: Cross-sectional and longitudinal analyses indicated that neurobehavioral disinhibition is a component of the liability to early age at onset of substance use disorder.  相似文献   
110.
Abstract
Viral and bacterial vaccines, especially for childhood use, are one of the most successful public health measures of the last two centuries and have a good safety record. However, there are still many diseases that are caused by infectious agents for which vaccines are not available. Our increasing ability to manipulate the immune system offers hope that, in the future, at least some of these infections may be prevented by vaccin­ation. A surprising recent development is the use of vaccine technology to test whether a range of other ­generally non-communicable diseases can be prevented (or at least controlled) in this way. Investigation of these diseases is still mainly at the experimental level, however the list includes different types of cancers, allergies, drug addiction and neurodegenerative diseases. (Intern Med J 2003; 33: 297−304)  相似文献   
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