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Reverse engineering is an important tool to generate CAD models. This paper describes an integrated approach for modeling parts from point cloud to surfaces or solids based on features and constraints. The approach allows designers to integrate reverse engineering and feature-based CAD system in the reconstruction of parts. This approach has two advantages over current practice and the reconstructed models produced by this method are feature-based and constraints satisfaction, which provides a higher level description of part geometry rather than the tedious low-level editing of geometric descriptions as in reverse engineering. This method also facilitates modification and innovative design to the reconstructed parts, which would be extremely difficult or impossible to accomplish if current reverse engineering method is applied. In addition, it is a more convenient and practical way for designers. To illustrate the validation of this integrated modeling approach, a more complicated example is illustrated based on the approach.

China is the largest producer and consumer of tobacco in the world. Consequently, the burden of tobacco-related diseases in China is enormous. Implementation of the World Health Organization Framework Convention on Tobacco Control (WHO FCTC) may lead to a significant reduction in tobacco-related morbidity and mortality both in China and globally. In this review, the authors summarize the epidemic of tobacco use and the progress made in implementing the WHO FCTC, including the promotion of legislation for smoke-free public places; smoking-cessation assistance; labeling of tobacco packaging; enforcement of bans on tobacco advertising, promotion, and sponsorship; increased taxes on tobacco products; increased tobacco prices; improvements in public awareness of the dangers of smoking; and identifying the barriers to implementing effective tobacco-control measures in China. Since the WHO FCTC officially took effect in China on January 9, 2006, China has taken some important steps, especially in promoting legislation for smoke-free public places. Because tobacco permeates the fabric of society, business, commerce, and politics in China, commitments and actions from the government are crucial, and implementing the WHO FCTC in China will be an arduous and long-term task.

Assessing combined anti-platelet therapy in suspected acute myocardial infarctionAspirin has been shown to be effective in the emergency treatment of acute myocardial infarction. It irreversibly inhibits platelet cyclo-oxygenase and thereby prevents the formation of the platelet aggregating agent thromboxane A2. Clopidogrel is an anti-platelet agent that acts by a different mechanism, inhibiting adenosine diphosphate-induced platelet aggregation. Simultaneous inhibition of both of these pathways might produce significantly greater anti-platelet effects than inhibition of either alone. The Second Chinese Cardiac Study (CCS-2) will reliably determine whether adding oral clopidogrel to aspirin for up to 4 weeks in hospital after suspected acute myocardial infarction can produce a greater reduction in the risk of major vascular events than can be achieved by giving aspirin alone. In order to be able to detect a further reduction of 10–15%, some 20000–40000 patients in over 1000 Chinese hospitals will be rando...

To explore the relationship between weekly alcohol drinking behavior and the prevalence of hypertension.Data was collected in a Kadoorie study of chronic disease in Wuzhong district, Suzhou city of Jiangsu province, China. Data from the baseline survey was used to describe the status of alcohol drinking and the prevalence of hypertension among local residents. Relationships between the frequency of alcohol drinking, consumption of alcohol, age when initiating weekly drinking behavior, drinking-related adverse conditions and the prevalence of hypertension, were studied by logistic regression.The rates on weekly alcohol drinking in the studied population were 40.7% in men and 0.6% in women. The amount of weekly average alcohol intake showed as 250.8 g in males and 47.2 g in females, with statistical significance seen between genders (P0.01). The prevalence rates of hypertension among male and female were 39.7% and 36.1% respectively, with significant difference (P0.01). Data from Multiple logistic regression analysis showed that when the frequency of alcohol drinkingor = 3 days per week or the weekly average alcohol intakeor = 100 grams, the risk would be higher to develop hypertension than in those non-drinkers (P0.01). The age of initiating behavior as weekly alcohol drinking younger than 20 years old or the dinking-related adverse condition appeared to be more than two kinds. The risks of developing hypertension were 1.50 times and 3.27 times than those non-drinkers in men but not in women.The frequency of drinking alcohol and the amount of alcohol intake per week was different between males and females. Along with the following factors as: increase of frequency on alcohol drinking per week, the amount of alcohol intake also increased. The advance of age related to the initiation of weekly drinking and the increase of alcohol-related adverse condition was also seen, the risk of hypertension showed an upward trend in males but not in females.

Long-term use of antiplatelet agents, statins, beta-blockers and angiotensin-converting enzyme inhibitors are proven therapies for secondary prevention in acute coronary syndrome. However, little is known of physicians' opinion about their use in China.In 2010, standard questionnaires were posted to chief cardiologists in 1397 geographically diverse and representative sample of tertiary and secondary hospitals in China, collecting information about their opinions on the recommended treatments for acute coronary syndrome.A total of 1009 (72%) cardiologists responded with a valid questionnaire. Of them, 77% reported routine use of all the four main secondary preventive treatments, with little difference between secondary and tertiary hospitals (75% vs. 79%, P = 0.16). Of the cardiologists reporting routine or selective use of aspirin, beta-blockers, statins and angiotensin-converting enzyme inhibitors, 94%, 85%, 73% and 86% would recommend indefinite use respectively. For all the 4 treatments combined, only 63.5% reported indefinite use at the same time, with no significant difference between secondary and tertiary hospitals (62% vs. 65%, P = 0.17), nor between hospitals with or without fast track for primary percutaneous coronary intervention (66% vs. 61%, P = 0.50).Although Chinese cardiologists seem well informed about the value of main secondary preventive treatments for acute coronary syndrome, there is still gap in their understanding of the need for combined and prolonged use of these treatments.

Seasonal variation in blood pressure had been observed in several studies on Western populations, but uncertainty remains about the strength of the relationship in other populations and the extent to which it was modified by other factors.This study was based on cross-sectional data from the China Kadoorie Biobank study with 53 260 men and women from the Suzhou area involved. Linear regression model was used to analyze the association of blood pressure with outdoor temperature-overall and in various subgroups.Blood pressure varied with the seasons, ascending in winter and descending in summer. The difference in systolic blood pressure (SBP) between summer and winter was 8.8 mm Hg in men and 7.0 mm Hg in women. SBP was inversely correlated with outdoor temperature, especially above 10°C, with every 10°C colder temperature causing 6.1 mm Hg increase of SBP. The seasonal variation in SBP was more obviously seen in older people and in those with lower body mass index.Blood pressure was strongly and inversely associated with outdoor temperature in the population in Suzhou area. Seasonal variation of blood pressure should be considered when the hypertension screening programs, clinical management and data management on hypertensive patients.

This study investigated current use of ACEI/ARB among high risk patients with coronary heart disease (CHD) in China and factors affecting ACEI/ARB use in these patients.This cross-sectional survey was performed between June to December 2007 and May to November 2009 in 51 hospitals from 14 cities. The characteristics of patients with established CHD were collected by electronic questionnaire.Only 45.8% high risk CHD patients were taking ACEI/ARB and the ACEI/ARB medication decreased significantly with time after initial CHD diagnosis. ACEI/ARB was taken in 46.1% CHD patients complicated with diabetes mellitus and in 56.3% CHD patients complicated with hypertension. Logistic regression analysis showed that comorbid hypertension was the strongest factor associated with ACEI/ARB use. In addition, male gender, history of myocardial infarction (MI), PCI and the time after initial CHD diagnosis were independent factors affecting the use of ACEI/ARB. Captopril was the most commonly prescribed ACEI in this cohort.ACEI/ARB is underused in secondary prevention among high risk CHD patients in China. It remains a major challenge for healthcare professionals and policy makers to make efforts on narrowing the gap between evidence and practice.

Well designed randomized trials and meta-analyses have clearly shown that statins reduce the risk of major vascular events, including ischemic stroke, in a wide range of patients and their routine use is recommended for patients at an increased cardiovascular risk. Survivors of a first ischemic stroke are at a risk of recurrence and of other vascular events and statins are generally recommended to reduce this risk. This study investigated how widely statins were being used for such patients in China.Totally 6422 patients with a history of ischemic stroke were identified by reviewing medical records at 51 highest-ranking hospitals in 14 cities in China, and invited to attend a screening clinic to assess eligibility for a randomized trial. Their current statin and other drug uses were recorded alongside clinical and demographic characteristics. Univariate chi-square test and multivariate Logistic regression were used to determine the factors associated with treatment.Only 24% of these patients reported currently taking a statin. The most important predictor of statin use among these patients was prior history of coronary heart disease. History of diabetes or hypertension, as well as treated in university affiliated hospitals is related to increased use. The status had improved significantly during a 2-year period. Atorvastatin (40%) and simvastatin (39%) were the most commonly used.In China, statins are still underused for secondary prevention among survivors of ischemic stroke. Reasons for this poor use need to be understood in order to increase use of these evidence based therapies.

To study the separate and combined effects of environment, lifestyle, physical characteristics, blood biomarkers and genetic factors on aetiology of major chronic diseases in adult Chinese.China Kadoorie Biobank (CKB) is a large blood-based prospective cohort study. The baseline survey took place in 5 urban and 5 rural areas across China during 2004-2008, with collection of data through questionnaire, physical examination and blood samples. Following the baseline survey, 5% of the randomly selected participants were surveyed in 2008, and repeated every 4-5 years. All participants would be followed for cause-specific mortality and morbidity through registries and for any hospital admission through linkages with health insurance databases.Overall, 512 891 adults aged 30-79 years (mean 51.5) were recruited, including 41.0% men and 55.9% from rural areas. Blood collection was successfully done in 99.98% of the participants. The prevalence of current regular smoking was 61.3% in men and 2.4% in women. The prevalence of regular alcohol consumption (i.e., weekly) was 33.4% in men and 2.1% in women. At the baseline, 41.8% of men and 45.3% of women were overweight or obese (i.e., BMI≥24.0 kg/m2) and 32.2% of men and 30.2% of women were hypertensive (i.e., SBP≥140 mm Hg or DBP≥90 mm Hg). For each of the main baseline variables, there were large variations on age, sex and areas of study.CKB seemed to be a powerful and rich resource in studying the environmental and genetic determinants of major chronic diseases in the Chinese population.

To investigate the current statin use among high-risk patients with atherosclerotic cardiovascular diseases in Chinese large hospitals.Clinical history and current medication were recorded in 11 783 patients with a history of atherosclerotic cardiovascular disease (CVD) from 39 highest-ranking hospitals in 10 Chinese cities.Indication for statin use was given for all screened patients and statin was not prescribed in up to 59.6% (7022) patients. For patients with statin use, medication time was shorter than their atherosclerotic CVD history in 1120 (23.5%) patients. The proportion of statin use among patients with ischemic stroke was 19.6%, among patients with coronary heart disease without ischemic stroke was 59.2%.Statin is underused in secondary prevention among patients with atherosclerotic CVD in China. There is a large gap between guideline recommended statin use and in practice. Thus, it remains a major challenge for healthcare professionals and policy makers to resolve this problem rapidly.

The expression of genes encoding a number of pathogenetic pathways involved in colorectal cancer could potentially act as prognostic markers. Large prospective studies are required to establish their relevance to disease prognosis.We investigated the relevance of 19 markers in 790 patients enrolled in a large randomised trial of 5-fluorouracil using immunohistochemistry and chromogenic in situ hybridisation. The relationship between overall 10-year survival and marker status was assessed.Minichromosome maintenance complex component 2 (MCM2) and cyclin A were significantly associated with overall survival. Elevated MCM2 expression was associated with a better prognosis (HR = 0.63, 95%CI: 0.46 - 0.86). Cyclin A expression above the median predicted an improved patient prognosis (HR = 0.71, 95%CI: 0.53 - 0.95). For mismatch repair deficiency and transforming growth factor β receptor type II (TGFBRII) overexpression there was a borderline association with a poorer prognosis (HR = 0.69, 95%CI: 0.46 - 1.04 and HR = 2.11, 95%CI: 1.02 - 4.40, respectively). No apparent associations were found for other markers.This study identified cell proliferation and cyclin A expression as prognostic indicators of patient outcome in colorectal cancer.

To investigate the degree and determinants of the use on statin among patients with atherosclerotic ischemic stroke in China.In the context of an international multi-center clinical trial being undertaken in China, 5585 patients with atherosclerotic ischemic stroke were screened in 39 prestigious hospitals in 10 cities. The characteristics collected through electronic questionnaire were described and analyzed.All the screened patients had indications for statins. Among those, 60% of the patients had a history from 3 months to 2 years of suffering from stroke. However, up to 80% of the patients were not using statins when screened. Even in those with statins, about 1/4 of the patients took statins for much shorter period than the history of stroke. The proportion using statins among IS patients with CHD was 4 times more than in those without CHD. Simvastatin and Atorvastatin were most commonly used.Statins were greatly underused for secondary prevention among patients with atherosclerotic ischemic stroke in China. There was a large gap between evidence and practice. It remains a major challenge for healthcare professionals and policy makers to tackle this problem more positively.

In order to exchange or share information on feature level among heterogeneous CAD systems. a feature-based data exchange method is proposed. All the data of the features of the feature model in source system are extracted, and decomposed or transformed, into an intermediate file. Then the feature model is recreated in target CAD system through the process of extracting, transforming and combining the data of features. The main data exchange strategies are also discussed in this paper. To validate this method, the data exchange modules for SolidWorks and Pro/ENGINEER are implemented, and some data exchange examples are given.

To assess the relationship between body mass index (BMI) and ischaemic heart disease (IHD) mortality, especially in populations with low mean BMI levels.We examined the data from a population-based, prospective cohort study of 220 000 Chinese men aged 40 - 79, who were enrolled in 1990 - 1991, and followed up ever since to 1/1/2006. Relative risks of the deaths from IHD by the baseline BMI were calculated, after controlling age, smoking, and the other potential confounding factors.The mean baseline BMI was 21.7 kg/m(2), and 2763 IHD deaths were recorded during the 15-year follow-up (6.8% of all deaths) program. Among men without prior vascular diseases at baseline, there was a J-shaped association between BMI and IHD mortality. When baseline BMI was above 20 kg/m(2), there was a strongly positive association of BMI with IHD risk, with each 5 kg/m(2) higher in BMI associated with 21% (95%CI: 9% - 35%, P = 0.0004) higher IHD mortality. Below this BMI range, the association appeared to be reverse, with the risk ratios as 1.00, 1.11, and 1.14, respectively, for men with BMI 20 - 21.9, 18 - 19.9, and18 kg/m(2). The excess IHD risk observed at low BMI levels persisted after restricting analysis to never smokers or excluding the first 3 years of follow-up.Lower BMI was associated with lower IHD risk among people in the so-called 'normal range' of BMI values (20 - 25 kg/m(2)). However, below that range, the association might well be reversed.

To examine the relationship between smoking and risk of esophageal cancer (EC), and present a theoretical framework of control selection in population-based case-control study which was incorporated into a nationwide retrospective survey of mortality in China.A large-scale population-based case-control study was incorporated into the nationwide retrospective survey of mortality conducted 1989 - 1991 in 24 urban cities selected by non-random sampling and 79 rural counties selected from 3000 counties included in the 1973 - 1975 cancer distribution survey by random sampling during. A questionnaire survey was conducted by home visit to investigate the death causes and smoking history of 19 734 deceased male adults who died of esophageal cancer during 1986 - 1988 at the ageor= 35. Two control groups were set up to undergo questionnaire survey by home visit to investigate the smoking history of the deceased persons and the informants. Control group I included the surviving spouses or other informants of 31 989 male adults who died of non-malignant digestive diseases during 1986 - 1988 at the ageor= 35, and control group II included 104 846 male spouses of the deceased female adults who died of different causes during 1986 - 1989 at the ageor= 35. The relative risks and population smoking attributable risks for EC were calculated using non-conditional logistic model, and the results were compared for consistency between the analyses using two different control groups.The EC absolute death rates were higher in the smokers than in the non-smokers in all urban and rural area groups. The total EC absolute death rate per 1000 among the non-smokers vs. smokers was 0.37:0.65 in the urban areas, 0.99:1.29 in the inland rural areas, and 1.09:1.62 in the coastal rural areas in the control group I, and there was a similar trend in the control group II. There was a significant dose-response relation between the period of smoking and the death risk of EC and between the daily cigarette consumption and the death risk of EC. The risk ratios, for example, for cigarette per day10, 10-, and 20- in the urban men were 1.42, 1.82, 2.22 in the control group I (trend test P0.01), and 1.57, 1.95, and 3.18 in the control group II (trend test P0.01).Smoking is an important risk factor for mortality from EC in China. Investigating the surviving spouses of the deceased patients is a creative, effective, and feasible trial, with the prerequisite of whole population-based survey, in study of the main types of death and the relevant risk factors.

To investigate the effects of all-trans retinoic acid (ATRA) on metastasis and its related proteins in human gastric cancer cells in vivo and in vitro.Gastric cancer cells, MGC80-3 and SGC-7901, were inoculated into spleen subcapsule of nude mice, respectively. Nude mice were administered with ATRA (0.7 mg/kg, ig) every other day. Six weeks later, nude mice were sacrificed. All the tumors formed in spleen and in liver were removed. Some of them were fixed, and then embedded. Others were kept in liquid nitrogen for further use. Expression level of proteins in tumor and in cell was analyzed by Western blot. Microvessel in tumor section was shown by immunohistochemistry and adhesive ability of cell to amnion was measured by adhesion assay.When inoculated nude mice were treated with ATRA, the xenograft tumors in spleen and metastatic tumors in liver were suppressed by 50 % respectively, and inhibition of microvessel formation in xenograft and metastatic tumors was also observed obviously. Although ATRA regulated expression of nm23 and mts1/p16 proteins at different patterns in vivo and in vitro, high ratio of nm23:mts1/p16 was in association with low adhesive activity of cells. In addition, ATRA induced ICAM-1 protein expression in vivo and in vitro.ATRA inhibits the growth of xenograft tumors and their metastasis to liver. This process may be associated with regulation of metastatic related proteins, including nm23, mts1/p16, and ICAM-1 in vivo and in vitro.