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991.
Cytogenetic analysis was performed on primary cultures of 21 squamous cell carcinomas of the esophagus (SCCE). Seven cases exhibited mosaic clonal chromosome abnormalities distributed as follows: two contained tetraploid cell populations, one with t(3;7)(p21;q11); two showed loss of the Y chromosome, one with double minutes; single cases demonstrated der(11)t(4;11)(q?27;q23); add(1)(p35) and del(4)(p12); and del(7)(p13), del(7)(q22q34), and der(11)t(7;11)(p?15;p?13). The remaining 14 cases had apparently normal karyotypes, possibly derived from stromal elements. These results demonstrate numerical abnormalities and the multiple occurrence of rearrangements involving chromosomes 7 and 11 in SCCE.  相似文献   
992.
Laboratory-based surveillance for diarrheal and respiratory illness was conducted at the 2009 Republic of the Philippines-United States Balikatan exercise to determine the presence of specific pathogens endemic in the locations where the military exercises were conducted. Ten stool and 6 respiratory specimens were obtained from individuals meeting case definitions for diarrhea or respiratory illness. Stool specimens were frozen in dry ice and remotely tested using enzyme-linked immunosorbent assay for Rotavirus, Astrovirus, Adenovirus, Entamoeba histolytica, Giardia, and Cryptosporidium and polymerase chain reaction for enterotoxigenic Escherichia coli, Campylobacter, Shigella, Vibrio, Salmonella, and Norovirus. Eight (4 for Campylobacter jejuni, 2 for Campylobacter coli, 1 for Norovirus genogroup II, and 1 for both Campylobacter coli and enterotoxigenic Escherichia coli) of 10 samples were positive for at least 1 enteric pathogen. MassTag polymerase chain reaction for influenza A and B, respiratory syncytial virus groups A and B, human coronavirus-229E and human coronavirus-OC43, human metapneumovirus, enterovirus, human parainfluenza viruses 2,3, and 4a, human adenovirus, Haemophilus influenzae, Neisseria meningitidis, Streptococcus pneumoniae, Legionella pneumonia, and Mycoplasma pneumonia was done on respiratory specimens. Out of 6 samples, 3 tested positive for H. influenzae; 1 tested positive for both H. influenzae and human parainfluenza virus 3; and 2 tested negative. Laboratory-based surveillance can be useful in determining etiologies of diarrheal and respiratory illness of deployed military personnel.  相似文献   
993.
The use of gadolinium-based hepatocyte-specific contrast agents (HSCAs) has increased markedly since their introduction, and hepatocellular phase imaging performed with an HSCA is now a key part of the standard magnetic resonance (MR) imaging work-up for focal liver lesions. An understanding of the mechanisms of action of HSCAs helps ensure their effective use. The optimal delay for hepatocellular phase image acquisition differs between the two currently available HSCAs, gadoxetic acid and gadobenate dimeglumine, and MR imaging protocols must be adjusted accordingly. In addition, familiarity with typical and atypical appearances of benign and malignant focal liver lesions at HSCA-enhanced hepatocellular phase MR imaging, along with knowledge of the processes that are most likely to produce atypical appearances, is required to achieve optimal diagnostic accuracy.  相似文献   
994.
Although the 11+ program has been shown to reduce injuries in sub‐elite football, program compliance is typically poor, suggesting that strategies to optimize delivery are necessary. This study investigated the effect of rescheduling Part 2 of the three‐part 11+ program on program effectiveness. Twenty‐five semi‐professional football clubs were randomly allocated to either a Standard‐11+ (n = 398 players) or P2post group (n = 408 players). Both groups performed the 11+ program at least twice a week throughout the 2017 football season. The Standard‐11+ group performed the entire 11+ program before training activities commenced, whereas the P2post group performed Parts 1 and 3 of the 11+ program before and Part 2 after training. Injuries, exposure, and individual player 11+ dose were monitored throughout the season. No significant between group difference in injury incidence rate (P2post vs Standard‐11+ = 11.8 vs 12.3 injuries/1000 h) was observed. Severe time loss injuries > 28 days (33 vs 58 injuries; P < .002) and total days lost to injury (4303 vs 5815 days; P < .001) were lower in the P2post group. A higher 11+ program dose was observed in the P2post (29.1 doses; 95% CI 27.9‐30.1) versus Standard‐11+ group (18.9 doses; 95% CI 17.6?20.2; P < .001). In semi‐professional football, rescheduling Part 2 of the 11+ program to the end of training maintained the effectiveness of the original 11+ program to reduce injury incidence. Importantly, rescheduling Part 2 improved player compliance and reduced the number of severe injuries and total injury burden, thereby enhancing effectiveness of the 11+ program.  相似文献   
995.
996.
The purpose of this study was to assess the effectiveness and safety of Gadolite Oral Suspension as a gastrointestinal (GI) contrast agent for MRI in a phase II and two phase III multicenter clinical trials. Gadolite was administered to 306 patients with known or suspected abdominal and/or pelvic disease. MRI with T1- and T2-weighted sequences was performed before and after ingestion. Efficacy was evaluated by having two masked readers rate the certainty of their MR diagnosis (0 = uncertain, 1 = probable, 2 = definite) on randomly presented pre- and post-Gadolite Oral Suspension enhanced images. Principal investigators also evaluated the images and established the final diagnosis. Vital signs, clinical chemistries, and adverse events were documented. Blood and urine samples were analyzed for gadolinium content to determine whether Gadolite Oral Suspension was absorbed systemically. Certainty in MR diagnosis increased significantly (P < .001) for both blinded readers between pre- and post-Gadolite images (.49–1.18 for reader 1; .46–1.53 for reader 2). Sensitivity, specificity, and accuracy also increased for both masked readers. No gadolinium was detected in blood or urine samples. There were no serious adverse events and no apparent drug-related trends in mean vital signs or laboratory values. Gadolite is a highly effective, safe, and well tolerated contrast agent for clinical use with MRI.  相似文献   
997.

Objectives

To investigate the added value of diffusion-weighted (DW) magnetic resonance (MR) imaging in the detection of infection in pancreatic fluid collections (PFC).

Methods

Forty-patients with PFC requiring endoscopic-transmural drainage underwent conventional-MR and DW-MR imaging (b?=?1000 s/mm2) before endoscopy. MR images were divided into two sets (set1, conventional-MR; set2, conventional-MR, DW-MR and ADC maps) and randomized. Two independent readers performed qualitative and quantitative (apparent diffusion coefficient, ADC) image analysis. Bacteriological analysis of PFC content was the gold standard. Non-parametric tests were used for comparisons. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy were calculated for the two sets for both readers. Receiver operating characteristic curves (ROC) were drawn to assess quantitative DW-MR imaging diagnostic performance.

Results

For both readers, sensitivity, specificity, NPV, PPV and accuracy for infected PFCs were higher for set2 (P?>?.05). ADC were lower in infected versus non-infected PFCs (P?≤?.031). Minimum ADC cut-off: 1,090×10-3 mm2/s for reader 1 and 1,012×10-3 mm2/s for reader 2 (sensitivity and specificity 67 % and 96 % for both readers).

Conclusion

Qualitative information provided by DW-MR may help to assess PFCs infection. Infected PFCs show significantly lower ADCs compared to non-infected ones.

Key Points

? DW improves MR diagnostic accuracy to detect infection of PFC ? Infected PFCs show lower ADC compared to non-infected ones (P?<?.031) ? DW-MR images are easy to interpret especially for non-experienced radiologist
  相似文献   
998.
Prostatic artery embolization (PAE) is a safe and efficacious procedure for benign prostatic hyperplasia (BPH), though is technically challenging. We present our experience of technical and clinical outcomes of robotic and manual PAE in patients with BPH. IRB-approved retrospective study of 40 consecutive patients 49–81 years old with moderate or severe grade BPH from May 2014 to July 2015: 20 robotic-assisted PAE (group 1), 20 manual PAE (group 2). Robotic-assisted PAE was performed using the Magellan Robotic System. American Urological Association (AUA-SI) score, cost, technical and clinical success, radiation dose, fluoroscopy, and procedure time were reviewed. Statistical analysis was performed within and between each group using paired t test and one-way analysis of variance respectively, at 1 and 3 months. No significant baseline differences in age and AUA-SI between groups. Technical success was 100% (group 1) and 95% (group 2). One unsuccessful subject from group 2 returned for a successful embolization using robotic assistance. Fluoroscopy and procedural times were similar between groups, with a non-significant lower patient radiation dose in group 1 (30,632.8 mGy/cm2 vs 35,890.9, p = 0.269). Disposable cost was significantly different between groups with the robotic-assisted PAE incurring a higher cost (group 1 $4530.2; group 2 $1588.5, p < 0.0001). Clinical improvement was significant in both arms at 3 months: group 1 mean change in AUA-SI of 8.3 (p = 0.006), group 2: 9.6 (p < 0.0001). No minor or major complications occurred. Robotic-assisted PAE offers technical success comparable to manual PAE, with similar clinical improvement with an increased cost.  相似文献   
999.

This study estimated ASD prevalence in a cohort of 3-year-old very preterm children (N?=?55) and investigated the usefulness of parent-reported ASD screeners and the ADOS-2. 12.7% received an ASD diagnosis by clinical judgment based on DSM-5 criteria. An additional 14.5% were classified as having a broader-autism-phenotype outcome. Sensitivity values for the screeners were poor, whereas specificity values ranged from poor to excellent. The ADOS-2 identified all children with ASD and had a fair specificity. These findings confirm the elevated ASD prevalence made by previous studies with preterm children but also highlight the challenges of successfully identifying ASD in this at-risk group. Caution is warranted when interpreting results of ASD instruments with the currently available cut-off scores and algorithms, especially when developmental challenges are present.

  相似文献   
1000.
Several small alkylammonium ions can eliminate, or even reverse, the usual dependence of the DNA transition temperature on base composition. For example, in 3 M tetramethylammonium chloride, or 2.4 M tetraethylammonium chloride, DNAs of different base compositions all melt at a common temperature, and with a greatly decreased breadth of transition reflecting only the sequence-independent components of melting cooperativity. At still higher concentrations of such additives, dG.dC-rich DNAs melt at lower temperatures than dA.dT-rich molecules. Circular dichroism spectra show that these additives alter the structure of the DNA double helix very little at room temperature. This differential (base-specific) effect on helix stability is investigated with several small additives related to the tetraalkylammonium ions. Additives larger than tetraethylammonium ion have little differential effect on helix stability. Preferential binding of ions to dA.dT base pairs, requiring fit into a "groove" of DNA, is consistent with these data and with equilibrium binding studies. These differential effects can be distinguished from general destabilizing effects, which are independent of specific features of macromolecular conformation or chemistry. Possible experimental uses of this ability to alter the base-composition-dependent components of the stability of the DNA helix are discussed, as well as the insight this phenomenon provides into the molecular basis for the differential stability of dA.dT and dG.dC base pairs.  相似文献   
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