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1.
A new implantable bladder volume-monitoring device based on the impedance measurement of the detrusor muscle is described. The system is completely autonomous and forms a mixed-signal (analogue/digital) feedback loop with a neuro-stimulator to rectify bladder dysfunctions (incontinence and retention) through neuromuscular stimulation techniques. A programmable instrumentation amplifier and a signal processing block, to eliminate the artefacts caused by the patient’s movements, have been designed and tested. The layout for the signal processing block has been realised in 0.8 μm BiCMOS technology.  相似文献   
2.
Contact biocides are a relatively new form of infection-resistant materials. Surfacine is a silver based antimicrobial coating that can be immobilized on the surface of most alloplastic materials used to fabricate devices. It exhibits broad-spectrum antimicrobial activity exclusively at the surface without elution and does not induce antimicrobial activity in contacting fluids such as urine regardless of volume. Because it is permanently immobilized on the material surface, the coating is nontoxic to cells and is not anticipated to exhibit immunogenicity, teratogenicity, or carcinogenicity.  相似文献   
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4.

Background:

Structural magnetic resonance imaging techniques are powerful tools for examining the effects of drug use on the brain. The nicotine and cannabis literature has demonstrated differences between nicotine cigarette smokers and cannabis users compared to controls in brain structure; however, less is known about the effects of co-occurring cannabis and tobacco use.

Methods:

We used voxel-based morphometry to examine gray matter volume differences between four groups: (1) cannabis-dependent individuals who do not smoke tobacco (Cs); (2) cannabis-dependent individuals who smoke tobacco (CTs); (3) cannabis-naïve, nicotine-dependent individuals who smoke tobacco (Ts); and (4) healthy controls (HCs). We also explored associations between gray matter volume and measures of cannabis and tobacco use.

Results:

A significant group effect was observed in the left putamen, thalamus, right precentral gyrus, and left cerebellum. Compared to HCs, the Cs, CTs, and Ts exhibited larger gray matter volumes in the left putamen. Cs also had larger gray matter volume than HCs in the right precentral gyrus. Cs and CTs exhibited smaller gray matter volume than HCs in the thalamus, and CTs and Ts had smaller left cerebellar gray matter volume than HCs.

Conclusions:

This study extends previous research that independently examined the effects of cannabis or tobacco use on brain structure by including an examination of co-occurring cannabis and tobacco use, and provides evidence that cannabis and tobacco exposure are associated with alterations in brain regions associated with addiction.  相似文献   
5.
6.
HCV can be classified into 6 major genotypes based on the phylogenetic analysis of the genomic sequences. The 3 major genotypes found in Thailand are 3, 1 and 6, respectively. In 2004, an epidemiological survey was carried out to evaluate the seroprevalence of HCV infections among populations aged 2-60 years in four provinces of Thailand, representing the North, Northeast, Center and South of the country, respectively. One hundred and twenty five out of 5,825 serum samples (2.15%) were positive for anti-HCV by ELISA. Fifty eight out of 100 anti-HCV positive samples (58.0%) were positive by RT-PCR of the 5'UTR. The core region of 45 representative samples was sequenced allowing classification into genotype variants 1a (6.7%), 1b (26.7%), 2a (2.2%), 2c (2.2%), 3a (51.1%), 3b (2.2%) and 6 (8.9%). This information might be crucial for public health surveillance and prevention of HCV infection.  相似文献   
7.
Existing serological methods for diagnosis of leptospirosis are still unsatisfactorily due mainly to their low accuracy. In this study, serum samples of 18 clinically diagnosed-, IgM dipstick positive-, MAT positive-leptospirosis patients (group 1) were analyzed by IgG Western blotting against SDS-PAGE separated-whole cell homogenates of pathogenic and non-pathogenic Leptospira spp. belonging to 20 serovars of 15 serogroups. The samples of group 1 were collected from the patients at days 3 to 10 after the fever onset (fist samples). Second and third samples could be obtained from 4 patients. Sera of the 22 patients with other febrile illnesses (group 2) and 22 healthy counterparts (group 3) were used as patient- and normal- controls, respectively. Irrespective of the serovar or serogroup of the pathogenic Leptospira spp. used as antigen in the Western blotting, all of the 18 sera of patients with leptospirosis (group 1) gave characteristic diffuse antigen-antibody reactive bands located at approximately 35-38 and 22-26 kDa; and thus 100% diagnostic sensitivity of the Western blot assay. Some serum samples of the leptospirosis patients also reacted to components located at 80-100, approximately 70, 60, 54, and 48 kDa. More bands or the early recognized bands with increased intensity were observed when tested the second and third samples. The characteristic bands were not seen when homogenates of L. biflexa, serogroup Semaranga, serovar Patoc (saprophytic) and L. biflexa, serogroup Andamana, serovar Andamana (non-pathogenic but can infect host) were used in the assay. Sera of groups 2 and 3 did not react to the components at the seven locations implying 100% diagnostic specificity of the IgG Western blot assay. While awaiting validation with more patients' samples, the IgG Western Blot analysis aiming at the detection of the characteristic antigen-antibody reactive bands described in this study has high potential for early, rapid, simple and accurate diagnosis of human leptospirosis.  相似文献   
8.

BACKGROUND

The Centers for Medicare & Medicaid Services publicly reports risk-standardized mortality rates (RSMRs) within 30-days of admission and, in 2013, risk-standardized unplanned readmission rates (RSRRs) within 30-days of discharge for patients hospitalized with acute myocardial infarction (AMI), heart failure (HF), and pneumonia. Current publicly reported data do not focus on variation in national results or annual changes.

OBJECTIVE

Describe U.S. hospital performance on AMI, HF, and pneumonia mortality and updated readmission measures to provide perspective on national performance variation.

DESIGN

To identify recent changes and variation in national hospital-level mortality and readmission for AMI, HF, and pneumonia, we performed cross-sectional panel analyses of national hospital performance on publicly reported measures.

PARTICIPANTS

Fee-for-service Medicare and Veterans Health Administration beneficiaries, 65 years or older, hospitalized with principal discharge diagnoses of AMI, HF, or pneumonia between July 2009 and June 2012. RSMRs/RSRRs were calculated using hierarchical logistic models risk-adjusted for age, sex, comorbidities, and patients’ clustering among hospitals.

Results

Median (range) RSMRs for AMI, HF, and pneumonia were 15.1% (9.4–21.0%), 11.3% (6.4–17.9%), and 11.4% (6.5–24.5%), respectively. Median (range) RSRRs for AMI, HF, and pneumonia were 18.2% (14.4–24.3%), 22.9% (17.1–30.7%), and 17.5% (13.6–24.0%), respectively. Median RSMRs declined for AMI (15.5% in 2009–2010, 15.4% in 2010–2011, 14.7% in 2011–2012) and remained similar for HF (11.5% in 2009–2010, 11.9% in 2010–2011, 11.7% in 2011–2012) and pneumonia (11.8% in 2009–2010, 11.9% in 2010–2011, 11.6% in 2011–2012). Median hospital-level RSRRs declined: AMI (18.5% in 2009–2010, 18.5% in 2010–2011, 17.7% in 2011–2012), HF (23.3% in 2009–2010, 23.1% in 2010–2011, 22.5% in 2011–2012), and pneumonia (17.7% in 2009–2010, 17.6% in 2010–2011, 17.3% in 2011–2012).

Conclusions

We report the first national unplanned readmission results demonstrating declining rates for all three conditions between 2009–2012. Simultaneously, AMI mortality continued to decline, pneumonia mortality was stable, and HF mortality experienced a small increase.  相似文献   
9.
Chronic renal impairment can lead to bone deterioration and abnormal bone morphology, but whether hydronephrosis is associated with bone loss remains unclear. Herein, we aimed to use computer‐assisted bone histomorphometric technique to investigate microstructural bone changes in Imprinting Control Region (ICR) mice with a spontaneous mutation that was associated with bilateral nonobstructive hydronephrosis (ICR/Mlac‐hydro). The results showed that 8‐week‐old ICR/Mlac‐hydro mice manifested decreases in trabecular bone number and thickness, and an increased trabecular separation, thereby leading to a reduction in trabecular bone volume compared with the wild‐type mice. Furthermore, histomorphometric parameters related to both bone resorption and formation, that is, eroded surface, osteoclast surface, and osteoblast surface, were much lower in ICR/Mlac‐hydro mice than in the wild type. A decrease in moment of inertia was found in ICR/Mlac‐hydro mice, indicating a decrease in bone strength. In conclusion, ICR/Mlac‐hydro mice exhibited trabecular bone loss, presumably caused by marked decreases in both osteoblast and osteoclast activities, which together reflected abnormally low bone turnover. Thus, this mouse strain appeared to be a valuable model for studying the hydronephrosis‐associated bone disease. Anat Rec, 297:208–214, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
10.
We put forward an impedometric protein-based biosensor platform suitable for point-of-care diagnostics. A hand-held scale impedance reader system is described for the detection of corresponding physiochemical changes as the immobilized proteins bind to the analyte molecules in the proximity of the microfabricated electrodes. Specifically, we study the viability of this approach for glucose biosensing purposes using genetically engineered glucokinase as receptor proteins. The proposed reagent-less biosensor offers a high sensitivity of 0.5 mM glucose concentration level in the physiologically relevant range of 0.5 mM to 7.5 mM with less than 10 s response time.  相似文献   
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