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1.
Lung and female breast cancers are highly prevalent worldwide. Although the association between exposure to ambient fine particulate matter (PM2.5) and lung cancer has been recognized, there is less evidence for associations with other common air pollutants such as nitrogen dioxide (NO2) and ozone (O3). Even less is known about potential associations between these pollutants and breast cancer. We conducted a population-based cohort study to investigate the associations of chronic exposure to PM2.5, NO2, O3 and redox-weighted average of NO2 and O3 (Ox) with incident lung and breast cancer, using the Ontario Population Health and Environment Cohort (ONPHEC), which includes all long-term residents aged 35–85 years who lived in Ontario, Canada, 2001–2015. Incident lung and breast cancers were ascertained using the Ontario Cancer Registry. Annual estimates of exposures were assigned to the residential postal codes of subjects for each year during follow-up. We used Cox proportional-hazards models adjusting for personal- and neighborhood-level covariates. Our cohorts for lung and breast cancer analyses included ~4.9 million individuals and ~2.5 million women, respectively. During follow-up, 100,146 incident cases of lung cancer and 91,146 incident cases of breast cancer were diagnosed. The fully adjusted analyses showed positive associations of lung cancer incidence with PM2.5 (hazard ratio [HR] = 1.02 [95% CI: 1.01–1.05] per 5.3 μg/m3) and NO2 (HR = 1.05 [95% CI: 1.03–1.07] per 14 ppb). No associations with lung cancer were observed for O3 or Ox. Relationships between PM2.5 and NO2 with lung cancer exhibited a sublinear shape. We did not find compelling evidence linking air pollution to breast cancer.  相似文献   
2.
Sphincter injury after anal dilatation demonstrated by anal endosonography.   总被引:5,自引:0,他引:5  
Anal dilatation is still used in the treatment of anal fissure and haemorrhoids. Using anorectal physiology and anal endosonography we have studied 12 men presenting with faecal incontinence following anal dilatation. Resting anal pressures were low, pudendal nerve latencies were normal; 11 men had a disrupted internal anal sphincter and in ten this was extensively fragmented. Three also had defects of the external anal sphincter. These findings demonstrate for the first time the nature of the structural injury which may be caused by anal dilatation.  相似文献   
3.
We present a new simple approach for automated, non-destructive measurement of the alpha-emitting radium isotopes ((223)Ra, (224)Ra, and (226)Ra) in water based on the emanation of their respective radon daughters ((219)Rn, (220)Rn, and (222)Rn). The method combines the high adsorption uptake of MnO(2) Resin for radium (K(d)=2.4 x 10(4)ml/g) over a wide pH range with the simplicity of the activity registration using a commercial radon-in-air analyzer (RAD7, DURRIDGE Company, Inc). Radium is first adsorbed onto the MnO(2) Resin by passing a water sample through the resin packed in a gas-tight glass cartridge. The same cartridge is then connected to the radon analyzer via a simple tubing system to circulate air through the resin and a drying system. The efficiency of the proposed system is determined by running standards prepared in the same manner. Our results indicate that the efficiency for (226)Ra is >22% if both (218)Po and (214)Po counts are collected. This is comparable with typical efficiencies for alpha spectrometry but with much less sample preparation. We estimate that an MDA of 0.8 pCi/L for (226)Ra may be obtained with this new approach using a 1L water sample and less than 4h of counting.  相似文献   
4.
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.  相似文献   
5.
The many uses of the U tube   总被引:2,自引:0,他引:2  
U tube placement was employed as an adjunct to complicated biliary procedures in 14 patients. We found the transhepatic tubes to be useful for stenting biliary anastomoses, maintaining biliary drainage, delivering localized irradiation, and acting as permanent external conduits. The tubes remained in placed an average of 15 months and as long as 40 months. The frequency of cholangitis was minimized by frequent tube exchange. The U-shaped configuration makes tube exchange easy and inexpensive to perform.  相似文献   
6.
This study reports the cardiovascular and renal actions of a novel and newly synthesized 27-amino acid peptide termed vasonatrin peptide (VNP). VNP is a chimera of atrial natriuretic peptide (ANP) and C-type natriuretic peptide (CNP). This synthetic peptide possesses the 22-amino acid structure of CNP, which is a cardiovascular selective peptide of endothelial origin and is structurally related to ANP. VNP also possesses the five-amino acid COOH terminus of ANP. The current study demonstrates both in vitro and in vivo that VNP possesses the venodilating actions of CNP, the natriuretic actions of ANP, and unique arterial vasodilating actions not associated with either ANP or CNP.  相似文献   
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The present study in the anesthetized dogs was designed to test the hypothesis that atrial natriuretic factor (ANF) attenuates whole kidney tubuloglomerular feedback (TGF) mediated decreases in renal blood flow (RBF) and glomerular filtration rate (GFR) produced by hypertonic saline (HS). Secondly, as adenosine (AD) has been implicated as a metabolic mediator of TGF, we also hypothesized that ANF would antagonize the renal actions of AD. To test this hypothesis, RBF and GFR were assessed in response to hypertonic saline (HS, 16%, i.r.) or adenosine (AD, 0.1 mumol/min, i.r.) in the presence and absence of exogenous ANF (100 ng/kg/min, i.r.). ANF attenuated HS-mediated reductions in GFR (HS, -39.6 +/- 9.8 ml/min vs. HS + ANF, -14.3 +/- 4.5 ml/min, P less than 0.05) and in RBF (HS, -143 +/- 35 ml/min vs. HS + ANF, -5 +/- 22 ml/min, P less than 0.05). GFR was reduced by AD (-9.2 +/- 3.0 ml/min, P less than 0.05), but maintained by AD + ANF (-0.4 +/- 2.0 ml/min, NS). A transient adenosine-mediated vasoconstriction was attenuated by ANF (AD, -54.5 +/- 3.6 ml/min vs. AD + ANF, -3.7 +/- 3.1 ml/min, P less than 0.005). We conclude that ANF at pharmacologic concentrations attenuates at the whole kidney level hypertonic saline and adenosine-mediated reductions in RBF and GFR.  相似文献   
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