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1.
Backscatter imaging is useful for inspecting structures that are accessible only from one side. However, indications provided by scattered radiation are typically weak, convoluted and difficult to interpret. This paper explores the use of the coded aperture technique to detect flaws using gamma-ray backscatter imaging. The viability of this approach is demonstrated with indications obtained from Monte Carlo simulations of radiation scattering measurements. The results show that, with a 2 mm wide beam of 137Cs photons, flaws as small as 1.5 mm in width can be detected using this technique. Indications of changes in flaw size, location, multiplicity and density were also observable. In addition, it is possible to quantify, from the decoded indications, the flaw location and its size.  相似文献   
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Background: Baseline clinical and physiological variables have been described as relevant predictors of survival among patients with idiopathic pulmonary fibrosis (IPF). However, substantial heterogeneity in both survival time and mortality has been observed with many of these predictive factors. The incidence and mortality rates of IPF vary from country to country, with race potentially contributing to such variations. Objective: We sought to describe baseline clinical features to determine their predictive value among Middle Eastern patients diagnosed with IPF. Methods: We retrospectively examined 61 patients diagnosed with IPF at a university hospital in Riyadh, Saudi Arabia. Results: At presentation, most patients exhibited either dyspnea or cough. The median survival time for all patients was 92 months. Diminished survival was significantly associated with finger clubbing (P = 0.01). Factors not influencing survival were age, gender, percent predicted forced vital capacity, percent predicted forced expiratory volume in 1 s, percent predicted total lung capacity, percent predicted diffusion capacity of the lung for carbon monoxide and resting oxygen saturation. Conclusions: Finger clubbing is a significant predictive variable and was associated with a 5‐fold increase in mortality. Other baseline demographic characteristics as well as pulmonary function tests were not predictive of prognosis in Middle Eastern patients with IPF. It appears that IPF patients of Middle Eastern descent have a longer median survival curve compared to other races. Please cite this paper as: Alhamad EH, Masood M, Shaik SA and Arafah M. Clinical and functional outcomes in Middle Eastern patients with idiopathic pulmonary fibrosis. The Clinical Respiratory Journal 2008; 2: 220–226.  相似文献   
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Background

Information regarding lung function parameters and functional capacity in renal failure and post renal transplantation patients with pulmonary hypertension (PH) is limited. The purpose of this study was to examine the clinical characteristics of patients with PH who were receiving hemodialysis (HD) or peritoneal dialysis (PD) or who had undergone renal transplantation.

Methods

A prospective study was performed on 116 patients (HD =55, PD =17, and post renal transplantation =44) who underwent Doppler echocardiography. PH was defined as systolic pulmonary artery pressure (SPAP) ≥40 mmHg. Demographic information, clinical characteristics, pulmonary function tests (PFTs) and the six-minute walk test (6MWT) were collected and compared between the patients with and without PH.

Results

Twelve (21.8%) patients receiving HD, four (23.5%) patients receiving PD, and eight (18.2%) post renal transplantation patients had PH. In the HD group, the physiological indicators (including pulmonary function test parameters, the final Borg score, and walking distance during the 6MWT) were all significantly lower in the patients with PH compared with those without PH (all P<0.0001). However, in the PD and post renal transplantation groups, no significant differences were noted in the demographic characteristics or in the physiological parameters when the PH patients were compared with those without PH (all P>0.05).

Conclusions

Among HD patients, marked aberrations in PFT results or walking distance may identify a subset of patients suffering from PH.  相似文献   
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International Urology and Nephrology - To evaluate the role of combination of N-acetylcysteine with stepwise ramping voltage in renal protection against the ischemic, vascular and oxidative effects...  相似文献   
8.

Background

As laparoscopic techniques and instrumentation advance, bariatric surgery has begun to be performed through smaller incisions and fewer ports. Since the visualization of the dorso-lateral portion of the left liver lobe is critical for most bariatric procedures, surgeons have developed various techniques for providing adequate liver retraction without compromising patient safety. Herein, we present our experience with a port-free internal liver retractor used for bariatric cases.

Methods

Endolift? does not require an additional port or anchoring to an external device. After insertion through an existing 5-mm port by means of the applier, one of the two attached clips (one on either end) was anchored to the left crus of the diaphragm while the other was fixed to the peritoneum above the right liver lobe through or beneath the falciform ligament. At the end of the surgery, the device was easily removed by using the applier.

Results

We used this technique for 31 Roux-en-Y gastric bypasses and 2 single-incision sleeve gastrectomies. There were 24 females and 9 males with a mean age of 46 and mean body mass index 45.0 kg/m2. The mean operative time was 136.5 min. The time required for the placement of the device was 1–3 min. The approach to the upper part of the stomach was satisfactory in all patients. No device-related complications were observed.

Conclusions

The internal liver retractor is easy to handle and provides adequate retraction and exposure for bariatric cases. It also has potential benefits for single-incision and reduced port laparoscopic procedures.  相似文献   
9.
The physico-chemical and biological characteristics of Alkhumra hemorrhagic fever virus (AHFV) are not yet known. The present study describes the thermal stability of this virus at different temperatures for different periods. The kinetics of thermal inactivation were studied, linear regressions were plotted, the Arrhenius equation was applied, and the activation energy was calculated accordingly. Titers of the residual virus were determined in median tissue culture infective dose (TCID50), and the rate of destruction of infectivity at various temperatures was determined. Infectivity of AHFV was completely lost upon heating for 3 minutes at 60 °C and for 30 min at 56 °C. However, the virus could maintain 33.2 % of its titer after heating for 60 min at 45 °C and 32 % of its titer after heating for 60 min at 50 °C. In conclusion, AHFV is thermo-labile, and its inactivation follows first-order kinetics.  相似文献   
10.
Tolcapone (T) is a novelcatechol-O-methyltransferase (COMT) inhibitor recentlyintroduced for the treatment of Parkinson's disease. Inclinical efficacy studies, T has been associated with alow incidence of diarrhea. The objectives of the study wereto examine whether T and its adjunctive drug Sinemet (S)could influence intestinal fluid and electrolytetransport as a possible cause for the diarrhea. The studies were conducted in conscious dogssurgically prepared with Thiry-Vella loops constructedfrom a 40-cm jejunal segment. A physiologically bufferedtest solution was perfused into the orad stoma and collected from the caudad stoma. Secretionswere collected at 15-min intervals and analyzed forvolume, electrolytes, lipid phosphorus, and protein. Theacute oral administration of T (10 and 30 mg/kg doses) was well tolerated. Concurrent acuteadministration of S (25 mg/kg) with T (30 mg/kg) wasalso well tolerated. The acute oral administration of Tinduced a dose-dependent efflux of intestinal fluid and electrolytes (sodium, potassium, chloride, andbicarbonate) secretion (P < 0.05). The oralcoadministration of S (25 mg/kg) with T (30 mg/kg)accelerated the onset of the stimulation of intestinalsecretion. Despite the significant stimulation ofintestinal secretion, none of the dogs developeddiarrhea, indicating the importance of intestinalcompensatory mechanisms. Neither T nor T&S affectedcalcium, lipid, or protein efflux rates, suggesting thatthe stimulated secretion was not a consequence ofintestinal mucosal injury. The chronic (seven-day)administration of T and T&S was associated withreduced intestinal secretory responses when comparedwith the acute administration of the same drugs; Senhanced the T-induced tolerance development. The basisfor such tolerance is unknown. In conclusion, the stimulatory systemic actions of tolcapone onintestinal secretion may, under certain conditions,contribute to the induction of diarrhea in susceptiblepatients.  相似文献   
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