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1.
A simple and reliable experimental model would be useful in human research on new drugs which target transient lower oesophageal sphincter (LOS) relaxation. The aim was to investigate the effect of repeated distensions on the rate of transient LOS relaxation, LOS pressure and motor function of the proximal stomach. Twelve healthy subjects were studied with a multilumen manometric assembly incorporating a sleeve sensor for the LOS and a bag positioned in the proximal stomach and connected to a barostat. Intrabag volume was set at 75% of the threshold for gastric discomfort and maintained for two 30-min distension periods separated by a 45-min washout with the bag deflated. The studies lasted 145 +/- 2 min. The rate of transient LOS relaxations was similar during the two distensions, 3.5;2-4 vs 3;2.5-4 (median;interquartile range) and so was LOS pressure. Baseline intrabag pressure, as a measure of gastric tone, and the number of pressure waves, as a measure of phasic contractions, were also similar, 11.3;9.3-12.3 mmHg vs 10.8;9.3-12.5 mmHg and 16;13-28 mmHg vs 19;15-29 mmHg, respectively. Our model allows to perform 1-day studies which can assess two experimental conditions on transient LOS relaxations and motor function of the proximal stomach within an acceptable time span.  相似文献   
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Thyroid microcarcinoma is nowaday defined as a tumor of one centimeter or less in the maximum diameter. It occurs in less than five per cent of all thyroid carcinomas. In personal experience four thyroid microcarcinomas have been found in specimens from 121 thyroidectomies and have been retrospectively reviewed clinical data and the long term follow-up of the patients. Total thyroidectomies nor prophylactic lymphadenectomies were never performed. All patients at present are well. Our purpose was to focus on the current surgical treatment of microcarcinoma. Many hypotheses are done to explain pathogenesis and fairly good prognosis of thyroid microcarcinomas, without univocal conclusions. Almost all authors agree that microcarcinoma of the thyroid gland is a low-aggressive tumor, with good biological behaviour, but the therapeutic strategies are not codified yet. Particularly, doubt still exists about the choice between total thyroidectomy and more conservative procedure, and lymphadenectomy, especially when tumor is found in specimens after surgery for benign disease. In conclusion, in our opinion conservative management is the best choice, provided that the patient is included in a correct long-term follow-up.  相似文献   
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BackgroundABO antibody titres are important in many clinical decisions; however, much variability is observed in titre results. For reliable and reproducible titre results, automated ABO titration methods have been developed. In this 10-site study, we evaluated the equivalency of the automated ABO titration assays on the Galileo NEO, a fully automated blood bank analyzer (Immucor, Inc.) to manual titration with gel Column Agglutination Technology (CAT), as well as the reproducibility of both methods.Materials and methodsTen different locations participated in this study. The equivalency study included 70 random samples at each site. The reproducibility study tested the same blinded 30-sample panel at each study site. Anti-A and anti-B IgM and IgG antibody titres were tested with both the automated and manual methods; additionally, dithiothreitol (DTT) treatment was used to inactivate IgM antibodies in the manual CAT method.ResultsThe equivalency between CAT manual method and Galileo NEO automated titres at each site ranged from 38 to 88%; equivalency for each isotype was 66.2% for IgM, 60.6% for IgG, and 88.5% for DTT-treated IgG. The reproducibility study evaluated the titre variation of each sample obtained from the 10 sites. The average titre ranges (in doubling dilutions) for the automated and manual methods, respectively, were 2.15±1.0 and 4.03±1.8 for IgM, and 1.53±0.7 and 4.10±1.9 for IgG; for the manual DTT-treated IgG, the average titre range was 3.45±1.8 doubling dilutions.DiscussionThe results demonstrated that the Galileo NEO automated and manual CAT ABO titres are not equivalent. However, the study also demonstrated that titre reproducibility is enhanced with the Galileo NEO automated ABO titration assays relative to the manual CAT ABO titration method. Therefore, to improve management of patients receiving care across multiple institutions, our study supports the use of automated ABO titration.  相似文献   
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Background: SARC-F is a simple sarcopenia screening tool. This study aimed to examine the validity of the Italian version of SARC-F. Methods: A total of 97 elderly individuals (37/60 males/females, 65 years and older) who met the study’s selection criteria were included. SARC-F was translated into the Italian language in a culturally responsive manner. The total score was calculated by adding the scores on the five items. The participants were divided into two groups according to the total score (SARC-F < 4 vs. SARC-F ≥ 4), and their associations with various factors (handgrip test, chair stand test, and Skeletal Muscle Index assessed by DXA) have been examined by gender. In addition, the tool’s validity was analyzed by comparing it with different international working group diagnostic criteria for sarcopenia. Results: The total prevalence of sarcopenia according to the SARC-F was 14.2% and, specifically, 12.8% among men and 14.3% in women. The sensitivity of the SARC-F was (male (M): 11–50% and female (F): 22–36%) medium-low compared with the European, international, and Asian criteria of sarcopenia; however, SARC-F showed a high specificity (M: 77.3–100% and F: 79.5–100%) and a moderate Cronbach’s alpha coefficient of (0.669 (CI95%: 0.358–0.830). The participants in the SARC-F ≥ 4 group had poorer handgrip for EWGSOP2 (p < 0.001) and chair stand (p < 0.001) than the participants in the SARC-F < 4 group. Conclusions: The Italian language version of SARC-F showed high specificity, moderate reliability, and good associations with other predictive tests. The Italian version of SARC-F appears to be a useful screening tool for the diagnosis of sarcopenia in Italian elderly populations.  相似文献   
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Tin-bronze alloys with a tin content of at least 10 wt% have excellent mechanical properties, wear resistance, and corrosion resistance. Among these alloys, Cu-10Sn was investigated in this study for production with the laser powder bed fusion process with a 500W Yb:YAG laser. In particular, a design of experiment (DoE) was developed in order to identify the optimal process parameters to obtain full density, low surface roughness, and high dimensional accuracy. Samples were characterized with Archimedes’ method and optical microscopy to determine their final density. It was shown that the first method is fast but not as reliable as the second one. A first mechanical characterization was performed through microhardness tests. Finally, a set of process parameters was identified to produce fully dense samples with low surface roughness and high accuracy. The results showed that the volumetric energy density could represent an approach that is too simplified, therefore limiting the direct correlation with the physical aspects of the process.  相似文献   
8.
Gastrointestinal stromal tumors are rare neoplasms arising from mesenchymal precursor cells of the gastrointestinal tract that may differentiate towards the interstitial cells of Cajal, pacemaker cells regulating autonomous motility of G.I. tract. Grading of GIST has been proven to be as difficult as their classification. Two thirds of GISTs are located in the stomach, 20-50% in the small bowel (one third in the duodenum), and 5-15% in colon and rectum; GISTs, however, may rarely be found also in the oesophagus, omentum, mesentery or the retroperitoneum. The distribuition of these tumors in the stomach is: pars media, 40%; antrum, 25%; pylorus, 20%; in less than 15%, GISTs location is next to the EGJ, in the cardia and in the iundus. The upper gastric third location of GISTs is not common, so their surgical management has been not yet well investigated. Total gastrectomy is considered the therapy of choice for the GIST located next to the EGJ, but wedge resection could be considered a surgical option in selected cases. The Authors describe 2 cases of GIST located just under the upper portion of the stomach and discuss about the different surgical options for GISTs of this region.  相似文献   
9.
Background: The study hypothesizes that nitrous oxide (N2O) releases opioid peptide in the brain stem, which results in inhibition of [gamma]-aminobutyric acid-mediated (GABAergic) neurons that tonically inhibit the descending noradrenergic inhibitory neurons (DNIN), resulting in activation of DNIN. In the spinal cord, activation of DNIN leads to the release of norepinephrine, which inhibits nociceptive processing through direct activation of [alpha]2 adrenoceptor and indirect activation of GABAergic neurons through [alpha]1 adrenoceptor. Arising from this hypothesis, it follows that GABAergic neurons will modulate the antinociceptive effect of N2O in diametrically opposite directions at supraspinal and spinal levels. The authors have tested this tenet and further examined the effect of midazolam, a GABA-mimetic agent, on N2O-induced antinociceptive effect.

Methods: Adult male Fischer rats were administered muscimol (GABAA receptor agonist) intracerebroventricularly (icv), gabazine (GABAA receptor antagonist) intrathecally (intrathecal), or midazolam intraperitoneally (intraperitoneal). Fifteen minutes later, they were exposed to air or 75% N2O and were subjected to the plantar test after 30 min of gas exposure. In some animals administered with midazolam, gas exposure was continued for 90 min, and the brain and spinal cord were examined immunohistochemically.

Results: The N2O-induced antinociceptive effect, which was attenuated by icv muscimol, intrathecal gabazine, and intraperitoneal midazolam. Midazolam inhibited N2O-induced c-Fos expression (a marker of neuronal activation) in the pontine A7 and spinal cord.  相似文献   

10.
Genitourinary neurofibromas with clitoral involvement in neurofibromatosis type 1 are rare, and even more infrequent are the neurofibromas involving genitalia in males. The most frequent presenting sign of neurofibroma in females is clitoromegaly with pseudopenis, and enlarged penis is the most common sign in males. Labium majus neurofibroma not associated with clitoral involvement is extremely rare. Magnetic resonance imaging demonstration of the neurofibromas has seldom been reported. We report 4 children, 3 girls and 1 boy, with plexiform neurofibromas involving the external genitalia. Three of the 4 patients had histologic confirmation of neurofibroma. Two girls with clitoral hypertrophy had a neurofibroma that infiltrated the clitoris and extended unilaterally to the lower bladder wall. One girl had a plexiform neurofibroma that affected a labium. One boy with asymmetric penile hypertrophy since 2 years of age and ipsilateral gluteal hypertrophy had plexiform neurofibromas that extended between the left lumbogluteal and penile regions, infiltrating the left rectum wall and bladder with compression of both structures, the left prostate, and the left half of the cavernous corpi with hypertrophy of this part and asymmetry of the penis. Magnetic resonance imaging demonstrated in all patients that external genitalia and plexiform neurofibroma formed images of nondetachable structures. However, hermaphroditism was discarded by chromosomal study in all 3 girls before ratifying the diagnosis of external genitalia neurofibroma.  相似文献   
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