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Background  

A community-based randomized control prenatal care trial was performed in a rural county of China during 2000-2003. The purpose of this paper is to describe the trial implementation and the impact of the trial on the utilization of prenatal care and perinatal outcomes.  相似文献   
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Objectives. Patients diagnosed with RA have been at an increasedrisk of many cancers and at a decreased risk of some cancers.We planned to revisit the theme by using a nation-wide populationof RA patients. Methods. An RA research database was constructed by identifyinghospitalized RA patients from the Hospital Discharge Registerand cancer patients from the Cancer Registry. Earlier studiesfrom Sweden have shown that some 75% of RA patients have beenhospitalized at some time point. Follow-up of 42 262 RA patientswas carried out from year 1980 to 2004 including separate follow-upsfor shorter intervals. Standardized incidence ratios (SIRs)were calculated for cancer in RA patients by comparing withsubjects without RA. Results. Many cancers were in excess in RA patients, especiallyHodgkin disease, non-Hodgkin lymphoma and squamous cell skincancer; a novel association was found for non-thyroid endocrinetumours. Colon, rectal and endometrial cancers were decreasedin RA patients. When RA patients were first hospitalized after1999, the SIRs for melanoma, squamous cell skin and upper aerodigestivetract cancers and for leukaemia were increased compared withprevious periods. Conclusions. This study, the largest so far published, quantifiedthe increased and decreased site-specific risks of cancer inRA patients. The recent increases in the risks of squamous cellskin and upper aerodigestive tract cancers, melanoma and leukaemiacall for continuous vigilance and recording of changes in treatment. KEY WORDS: Subsequent cancer, Changing risk, Age at onset, National databases Submitted 31 January 2008; revised version accepted 3 March 2008.  相似文献   
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Air-coupled non-contact mechanical property determination of drug tablets   总被引:1,自引:1,他引:0  
A non-contact/non-destructive technique for determining the mechanical properties of coated drug tablets is presented. In the current measurement approach, air-coupled excitation and laser interferometric detection are utilized and their effectiveness in characterizing the mechanical properties of a drug tablet by examining its vibrational resonance frequencies is demonstrated. The drug tablet is vibrated via an acoustic field of an air-coupled transducer in a frequency range sufficiently high to excite its several vibrational modes (harmonics). The tablet surface vibrational responses at measurement points are acquired by a laser vibrometer in a non-contact manner. An iterative computational procedure based on the finite element method is developed to extract the mechanical properties of the coated tablet from a subset of its measured resonance frequencies. The mechanical properties measured by this technique are compared to those obtained by a standard contact ultrasonic measurement method and a good agreement is found. Sensitivities of the resonance frequencies to the changes in the tablet mechanical properties are also obtained and discussed. The presented non-destructive technique requires no physical contact with the tablet and operates in the microsecond time-scale. Therefore, it could be employed for rapid monitoring and characterization applications.  相似文献   
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BACKGROUND: Variable expression of the coxsackie and adenovirus receptor (CAR) has limited gene transfer efficacy to many types of tumors. Consequently, tropism-modified adenoviruses have been developed for enhanced infectivity. To the authors' knowledge, targeting approaches for nonsmall cell lung cancer (NSCLC) have not been comprehensively evaluated. The current hypothesis was that modified adenoviruses could be used for increasing gene transfer to and killing of NSCLC cells in vitro and in vivo. METHODS: Ten NSCLC cell lines were analyzed to represent the different NSCLC histologies. Because clinical tumors may differ from established cell lines, 6 clinical specimens fresh from patients were analyzed. For in vivo studies, a novel orthotopic murine model of advanced lung cancer was developed. Because tumor response is difficult to quantitate in orthotopic models, noninvasive imaging of green fluorescent protein (GFP) was utilized as a surrogate for tumor size measurements. RESULTS: Adenoviruses whose capsids were modified with RGD-4C, the serotype 3 knob, or polylysine displayed increased gene transfer to NSCLC cell lines and clinical samples in comparison to serotype 5 viruses. Conditionally replicating oncolytic adenoviruses (CRAds) with the same modifications showed enhanced therapeutic efficiency in vitro and in vivo. The median survival of mice treated with Ad5.pK7-Delta24 or Ad5-Delta24RGD increased 37% (P<.01). GFP imaging allowed noninvasive individualized detection of response and recurrence. CONCLUSIONS: Targeting of adenovirus to heterologous receptors can improve killing of NSCLC cells. Utilization of clinical samples and an orthotopic model of advanced lung cancer may provide clinically relevant translational data.  相似文献   
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