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241.
To date, there have been few studies to evaluate directly the relationship between binocular visual stress and reading performance. This study employed the cloze procedure to demonstrate the effects of nearpoint stress on performance and efficiency in reading comprehension. Using 19 third year optometry students as subjects, binocular stress was simulated by -2.00 D lenses. Performance, as determined by the time to complete the task, was significantly reduced (p less than .03), but no significant differences in accuracy scores were measured.  相似文献   
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A multidrug-resistant fljB-lacking Salmonella enterica serovar [4,5,12:i:-] emerged in Spain in 1997. We analyzed the genome from four strains of this serovar using a microarray containing almost all the predicted protein coding regions of serovar Typhimurium strain LT2, including the pSLT plasmid. Only a few differences from serovar Typhimurium LT2 were observed, suggesting the serovar to be Typhimurium as well. Six regions of interest were identified from the microarray data. Cluster I was a deletion of 13 genes, corresponding to part of the regulon responsible for the anaerobic assimilation of allantoin. Clusters II and IV were associated with the absence of the Fels-1 and Fels-2 prophage. Cluster III was a small group of Gifsy-1 prophage-related genes that appeared to be deleted or replaced. Cluster V was a deletion of 16 genes, including iroB and the operon fljAB, which is reflected in the serovar designation. Region VI was the gene STM2240, which appears to have an additional homologue in these strains. The regions spanning the deletions involving the allantoin operon and the fljAB operon were PCR amplified and sequenced. PCR across these regions may be an effective marker for this particular emergent serovar. While the microarray data for all isolates of the new serovar were essentially identical for all LT2 chromosomal genes, the isolates differed in their similarity to pSLT, consistent with the heterogeneity in plasmid content among isolates of the new serovar. Recent isolates have acquired a more-complete subset of homologues to this virulence plasmid. In general, microarrays can provide useful complementary data to other typing methods.  相似文献   
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BACKGROUND/AIMS: The mechanisms leading to osteoporosis in alcoholic liver disease remain poorly understood. Recently identified soluble circulating osteoprotegerin (OPG), is the osteoclastogenesis inhibitory factor. It acts as a decoy receptor for osteoclast activating factor, receptor activator of nuclear factor-kappaB ligand (RANKL), and impairs osteoclast function. The aim of our study was to investigate the OPG/RANKL system in alcoholic cirrhotic patients and their correlation with biochemical marker of bone turnover. PATIENTS AND METHODS: Serum OPG, RANKL, osteocalcin (OC), C-terminal cross-linking telopeptide of type I collagen (CTX-I), bone alkaline phosphatase activity (bALP), and urinary hydroxyproline were measured in 30 patients with alcoholic cirrhosis, and in 20 age- and sex-matched healthy controls. RESULTS: OPG levels were significantly increased in patients with alcoholic cirrhosis compared with healthy subjects (5.9 pmol/l, range 2.7-9.0 vs 4.1 pmol/l, range 1.2-6.6; P < 0.001). RANKL levels were significantly higher in patients with cirrhosis (0.48 pmol/l, range 0.01-1.34) than in healthy subjects (0.11 pmol/l, range 0.01-0.90). There was a positive correlation between serum OPG and RANKL (r = 0.37; P < 0.001), bALP (r = 0.66; P < 0.001) and urinary hydroxyproline (r = 0.51; P < 0.05) but not with OC and CTX-I. CONCLUSIONS: OPG might partly represent a compensating mechanism to the negative balance of bone remodelling in patients with alcoholic cirrhosis.  相似文献   
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Background

Natural orifice transluminal endoscopic surgery procedures have evolved over the past few years. A transvaginal approach is a promising alternative for intraperitoneal procedures. Our objective was to evaluate the safety and feasibility of transvaginal organ extraction.

Methods

This institutional review board-approved protocol involved retrospective review of an ongoing prospective study. Female subjects who presented to our hospital for elective cholecystectomy, appendectomy, or sleeve gastrectomy were offered participation in the study. Eligible patients met the following criteria: age between 18 and 75, diagnosis of gallbladder disease, acute appendicitis, or morbid obesity who desired surgical treatment. A hybrid transvaginal natural orifice approach was used in this series.

Results

Thirty-four women underwent transvaginal organ extraction between September 2007 and January 2012. The mean age was 40 ± 12.1 years (range 23–63 years). The mean body mass index was 27 ± 6.4 kg/m2 (range 16–43 kg/m2). All patients had an American Society of Anesthesiologists classification of two or below. The mean operative time for cholecystectomy, appendectomy, and sleeve gastrectomy was 90, 71, and 135 min, respectively. There were no conversions to open operation and no intraoperative complications. The mean hospital stay was 2 days for all cases. Patients were followed for a mean of 24 months (range 1–61 months). There were two pregnancies and two successful vaginal deliveries. Six patients (18 %) had minor complaints of spotting or heavy menses in the immediate postoperative period that resolved with conservative measures. There were no abdominal wall complications. There were no long-term complications and no mortalities.

Conclusions

This initial experience suggests that this surgical approach is safe, does not increase length of stay, and has no long-term vaginal complications. Given this attractive profile, a transvaginal approach may prove to be a superior mode of organ extraction, although randomized studies and long-term follow-up are needed.  相似文献   
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AimsTo ascertain in real practice the diagnosis rate of diabetic retinopathy (DR) in patients considered to have positive screening test by general practitioners (GPs) and what are the reasons for the false positive diagnosis.MethodsFour GPs previously instructed in the interpretation of retinal photographs evaluated the digital retinography images of patients with diabetes obtained during a 2-year period. When the images were considered normal, a new appointment was scheduled for 1 year later and a report was emailed to the referring physician. Patients with any sign of DR or other suspicious retinal alterations and those whose images were considered difficult or impossible to assess were referred to an ophthalmologist.ResultsA total of 2750 patients were referred for screening. The images of 2036 (74%) patients were considered normal, and the images of 714 (26%) patients were sent to ophthalmologists. Among the referred patients, 392 (55%) did not have DR, 244 (34%) had DR, and 78 (11%) had unreadable images. The retinal images of 240 patients whose fundi were considered normal were read again by ophthalmologists to evaluate false negatives. Of them, 16 patients (7%) had DR but only two patients (1%) had treatable DR.ConclusionsAfter adequate training, GPs can screen for DR with a high level of accuracy using non-mydriatic retinography. There is a need to strengthen the training of GPs in order to recognize non-visual threatening abnormalities.  相似文献   
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