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1.
European Radiology - The strongest adverse prognostic factor in myxoid/round cell liposarcomas (MRC-LPS) is the presence of a round cell component above 5% within the tumor bulk. Its identification...  相似文献   
2.
Investigative studies of white matter (WM) brain structures using diffusion MRI (dMRI) tractography frequently require manual WM bundle segmentation, often called “virtual dissection.” Human errors and personal decisions make these manual segmentations hard to reproduce, which have not yet been quantified by the dMRI community. It is our opinion that if the field of dMRI tractography wants to be taken seriously as a widespread clinical tool, it is imperative to harmonize WM bundle segmentations and develop protocols aimed to be used in clinical settings. The EADC‐ADNI Harmonized Hippocampal Protocol achieved such standardization through a series of steps that must be reproduced for every WM bundle. This article is an observation of the problematic. A specific bundle segmentation protocol was used in order to provide a real‐life example, but the contribution of this article is to discuss the need for reproducibility and standardized protocol, as for any measurement tool. This study required the participation of 11 experts and 13 nonexperts in neuroanatomy and “virtual dissection” across various laboratories and hospitals. Intra‐rater agreement (Dice score) was approximately 0.77, while inter‐rater was approximately 0.65. The protocol provided to participants was not necessarily optimal, but its design mimics, in essence, what will be required in future protocols. Reporting tractometry results such as average fractional anisotropy, volume or streamline count of a particular bundle without a sufficient reproducibility score could make the analysis and interpretations more difficult. Coordinated efforts by the diffusion MRI tractography community are needed to quantify and account for reproducibility of WM bundle extraction protocols in this era of open and collaborative science.  相似文献   
3.
Sonodynamic therapy (SDT) consists of the synergetic interaction between ultrasound and a chemical agent. In SDT, the cytotoxicity is triggered by ultrasonic stimuli, notably through cavitation. The unique features of SDT are relevant in the clinical context more than ever: the need for efficacy, accuracy, and safety while being noninvasive and preserving the patient's quality of life. However, despite the promising results of this technique, only a few clinical reports describe the use of SDT. The objective of this article is to provide an extensive overview of the clinical and preclinical research conducted in vivo on SDT, to identify the limitations, and to detail the developed strategies to overcome them.  相似文献   
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Granulomatous slack skin is an indolent T-cell lymphoma, considered to be a variant of mycosis fungoides. Clinically it is characterized by areas of redundant skin, wrinkled, inelastic, with variable erythema and infiltration besides a poikilodermic surface. A differential diagnosis unknown to most dermatologists is the giant cell tumor of soft tissue, which is an extremely rare low-grade sarcoma. The authors report a patient who had undergone extensive surgery because of a primary diagnosis of giant cell tumor of soft tissue, but which proved to be granulomatous slack skin after a second interventional procedure with confirmatory histopathology.  相似文献   
6.
Background: Blockade of parietal nociceptive afferents by the use of continuous wound infiltration with local anesthetics may be beneficial in a multimodal approach to postoperative pain management after major surgery. The role of continuous preperitoneal infusion of ropivacaine for pain relief and postoperative recovery after open colorectal resections was evaluated in a randomized, double-blinded, placebo-controlled trial.

Methods: After obtaining written informed consents, a multiholed wound catheter was placed by the surgeon in the preperitoneal space at the end of surgery in patients scheduled to undergo elective open colorectal resection by midline incision. They were thereafter randomly assigned to receive through the catheter either 0.2% ropivacaine (10-ml bolus followed by an infusion of 10 ml/h during 48 h) or the same protocol with 0.9% NaCl. In addition, all patients received patient-controlled intravenous morphine analgesia.

Results: Twenty-one patients were evaluated in each group. Compared with preperitoneal saline, ropivacaine infusion reduced morphine consumption during the first 72 h and improved pain relief at rest during 12 h and while coughing during 48 h. Sleep quality was also better during the first two postoperative nights. Time to recovery of bowel function (74 +/- 19 vs. 105 +/- 54 h; P = 0.02) and duration of hospital stay (115 +/- 25 vs. 147 +/- 53 h; P = 0.02) were significantly reduced in the ropivacaine group. Ropivacaine plasma concentrations remained below the level of toxicity. No side effects were observed.  相似文献   

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The purpose of this study was to test the capacity of oestradiol to modulate the stimulating effect of a-aminobutyric acid (GABA) on serotonin (5-HT) metabolism, previously described in the Suprachiasmatic area of the male rat. After an in vivo stimulation of GABA transmission by systemic administration of a GABA-transaminase inhibitor (amino-oxyacetic acid) or a GABAB agonist (RS-baclofen), the 5-HT metabolism was studied in the Suprachiasmatic area of ovariectomized, and ovariectomized oestradiol-treated rats. Amino-oxyacetic acid or RS-baclofen treatment increased the endogenous content of 5-HT in the Suprachiasmatic area of males and ovariectomized rats. These two treatments were without effect in ovariectomized oestradiol-treated rats. GABA transmission stimulation induced by amino-oxyacetic acid treatment failed to affect the release and synthesis of 5-HT in ovariectomized oestradiol-treated rats while it increased these two parameters of 5-HT metabolism in the Suprachiasmatic area of male and ovariectomized rats. To investigate the main target of oestradiol effect, comparative studies of the serotoninergic and GABAergic metabolism in the Suprachiasmatic area were performed in the three experimental groups. Under our experimental conditions the endogenous 5-HT metabolism was similar between ovariectomized and ovariectomized oestradiol-treated rats. Nevertheless, 5-HT metabolism was higher in the two female groups than in the male group. Neither GABA metabolism nor GABAergic response to GABA-related drug treatment differed between ovariectomized, and ovariectomized oestradiol-treated rats. However, the turnover of GABA was higher when compared to the two female groups. It is concluded that the lack of 5-HT responsiveness to GABA transmission stimulation in ovariectomized oestradiol-treated rats was not related to an effect of oestradiol on 5-HT metabolism or to an effect of the steroid on GABA turnover. Furthermore, our results suggest a sex difference in the activity of serotoninergic and GABAergic systems in the Suprachiasmatic area.  相似文献   
9.
We provide microscopic evidence that motile rod-shaped forms of Ramlibacter tataouinensis TTB310 are formed from dividing cyst-like cells. Careful estimation of the size of the two morphotypes was conducted using optical and transmission electron microscopy (TEM). The cyst-like cell was shown to be a sphere with a diameter Dc=850 nm. The rod-shaped form was a round-ended cylinder with length Lr=2.91 microm and diameter Dr=239 nm. The membrane area of the two morphotypes was the same. However, the formation of rods from cysts involved loss of two-thirds of the cell volume. TEM showed that, prior to division and transition into rods, cysts contained condensed cytoplasmic material. These results suggest that the morphological transition occurs by pure reshaping of cells.  相似文献   
10.
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