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31.
Antonello D rea Juri Radmilovic reina Carbone Alberto Forni Ercole Tagliamonte Lucia Riegler Biagio Liccardo Fabio Crescibene Cesare Sirignano Giovanna Esposito Eduardo Bossone 《World journal of radiology》2020,12(11):261-271
The integrated clinical, laboratory and ultrasound approach is essential for the diagnosis, evaluation and monitoring of the patient's therapy in coronavirus disease 2019 pneumonia. The ideal imaging approach in this context is not yet well defined. Chest X-ray is characterized by low sensitivity in identifying earlier lung changes. The "bedside" pulmonary ultrasound has an undeniable series of advantages in the patient at high infectious risk and can provide incremental data in the respiratory intensive care for the serial control of the individual patient as well as for the home delivery of the stabilized subjects. Pulmonary computed tomography shows high sensitivity but should not be routinely performed in all patients, because in the first 48 h it can be absolutely negative and in the late phase the imaging findings may not change the therapeutic approach. Echocardiography should be limited to patients with hemodynamic instability to assess ventricular function and pulmonary pressures. 相似文献
32.
The outcome of root canal treatment is based on efficient disinfection of the root canal system and prevention of reinfection. Current chemomechanical cleaning methods do not always achieve these goals, and insufficient root canal disinfection is the main reason for endodontic failure. Due to high energy content and specific characteristics of laser light, laser treatment has been proposed for cleaning and disinfecting the root canal system. This paper reviews the literature covering the effect of Er:YAG, Er,Cr:YSGG, Nd:YAG and diode laser on the root canal wall in the removal of smear layer and against intracanal bacteria. Recently, the use of laser energy to induce cavitation and acoustic streaming of intracanal irrigants has been investigated. Based on recent literature, it can be concluded that lasers have bactericidal effects. However, they still cannot replace sodium hypochlorite and should be considered as an adjunct to the current chemical root canal disinfection protocols. Certain lasers can help in removing the smear layer and debris and can modify the morphology of the root canal wall. Unfortunately, there have not been enough randomized clinical studies evaluating endodontic treatment outcome following the use of laser.Key words: Disinfection, Root Calan Preparation; Laser Therapy, Low-Level; Smear Layer 相似文献
33.
Masahiro To Yohei Kamata Juri Saruta Tomoko Shimizu Takenori Sato Yusuke Kondo Takashi Hayashi Nobushiro Hamada Keiichi Tsukinoki 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2013,46(1):25-34
It is important to understand the onset of periodontal disease in terms of bacterial infection and host factors. Host-bacteria interactions can be elicited in human cultured cells and animal models, but these models provide only limited biological information about human host reactions against bacterial attacks. Development of an in vivo model using human gingival tissue is needed. We established an in vivo model using nu/nu mice and evaluated host defense following bacterial infection in human gingiva. Human gingival samples were collected from periodontitis patients and transplanted in nu/nu mouse subdermis. After 2 weeks, human characteristics were confirmed by positive immunohistochemical reactions for human-specific markers. We used this model to investigate human β-defensin-2 (hBD-2), an antimicrobial peptide that contributes to initial defense against bacterial invasion. Using real-time polymerase chain reaction, in situ hybridization, and immunohistochemistry, we investigated whether hBD-2 expression was induced in human gingiva as a response to Porphyromonas gingivalis as a periodontal pathogen. Two hours after infection with bacteria, we detected increased expression of hBD-2 mRNA, which was localized in the epithelium of human gingiva. Using our in vivo model, we concluded that increased hBD-2 may play an important role in early defense from bacterial infection in human gingival epithelium. 相似文献
34.
Sabine Vollstädt‐Klein Svenja Wichert Juri Rabinstein Mira Bühler Oliver Klein Gabriele Ende Derik Hermann Karl Mann 《Addiction (Abingdon, England)》2010,105(10):1741-1749
Aims During the development of drug addiction, initial hedonic effects decrease when substance use becomes habitual and ultimately compulsive. Animal research suggests that these changes are represented by a transition from prefrontal cortical control to subcortical striatal control and within the striatum from ventral to dorsal domains of the striatum, but only limited evidence exists in humans. In this study we address this hypothesis in the context of alcohol dependence. Design, setting and participants Non‐abstinent heavy social drinkers (n = 21, 5.0 ± 1.5 drinks/day, 13 of them were alcohol‐dependent according to DSM‐IV) and light social drinkers (n = 10, 0.4 ± 0.4 drinks/day) were examined. Measurements We used a cue‐reactivity functional magnetic resonance imaging (fMRI) design during which pictures of alcoholic beverages and neutral control stimuli were presented. Findings In the dorsal striatum heavy drinkers showed significant higher activations compared to light drinkers, whereas light social drinkers showed higher cue‐induced fMRI activations in the ventral striatum and in prefrontal areas compared to heavy social drinkers [region of interest analyses, P < 0.05 false discovery rate (FDR)‐corrected]. Correspondingly, ventral striatal activation in heavy drinkers correlated negatively with obsessive‐compulsive craving, and furthermore we found a positive association between cue‐induced activation in the dorsal striatum and obsessive‐compulsive craving in all participants. Conclusions In line with our hypothesis we found higher cue‐induced activation of the ventral striatum in social compared to heavy drinkers, and higher dorsal striatal activation in heavy drinkers. Increased prefrontal activation may indicate that social drinkers activate cortical control when viewing alcohol cues, which may prevent the development of heavy drinking or alcohol dependence. Our results suggest differentiating treatment research depending on whether alcohol use is hedonic or compulsive. 相似文献
35.
Amit Verma Sushovan Guha Parmeswaran Diagaradjane Ajaikumar B Kunnumakkara Angela M Sanguino Gabriel Lopez-Berestein Anil K Sood Bharat B Aggarwal Sunil Krishnan Juri G Gelovani Kapil Mehta 《Clinical cancer research》2008,14(8):2476-2483
PURPOSE: Tissue transglutaminase (TG2) is a multifunctional protein that is implicated in development of drug resistance and metastasis. Therefore, we examined therapeutic targeting of TG2 for inhibiting growth and metastasis of in vivo growing pancreatic ductal adenocarcinoma (PDAC) in nude mice. EXPERIMENTAL DESIGN: We implanted Panc-28 pancreatic cancer cells to induce orthotopic PDAC tumors in nude mice and determined the efficacy of liposomal TG2 small interfering RNA (siRNA) either alone or in combination with gemcitabine. RESULTS: We show that down-regulation of endogenous TG2 by siRNA could effectively block the growth of PDAC. Moreover, down-regulation of TG2 significantly enhanced the therapeutic efficacy of gemcitabine against PDAC and inhibited metastatic spread of the disease. The antitumor activity was related to inhibition of proliferation, angiogenesis, and Akt phosphorylation. CONCLUSION: siRNA-mediated down-regulation of TG2 represents a promising therapeutic approach for improved treatment of PDAC. 相似文献
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37.
A patient was treated with radiation therapy to the right hemiabdomen for a large cavernous hemangioma of the liver. Twenty years later, a squamous cell carcinoma of the right renal pelvis was diagnosed. The occurence of such a tumor as a late complication of irradiation has not been described before. 相似文献
38.
Plotkin M Amthauer H Eisenacher J Wurm R Michel R Wust P Stockhammer F Röttgen R Gutberlet M Ruf J Felix R 《Neuroradiology》2005,47(1):18-26
The value of single-photon emission tomography (SPECT) using iodine-123-alpha-methyl-tyrosine (IMT) for the diagnosis of recurrent or residual gliomas is well established. In the current study we investigated whether IMT-SPECT could also be useful in the follow-up of brain metastases and other intracranial tumours of non-astrocytic origin. The study included 22 patients with suspected recurrent intracranial tumours of non-astrocytic origin (12 brain metastases, one supratentorial primitive neuroendocrine tumour (PNET), one rhabdoid tumour, two clivus chordomas, three ependymomas, two pituitary tumours, one anaplastic meningioma) who had previously been treated by surgery and/or radio/chemotherapy. SPECT results were correlated with clinical and MRI follow-up data. The study was true positive in 13 patients, true negative in five, false positive in one and false negative in three patients. Notably, all false negative findings were <13 mm. The resulting sensitivity of the IMT-SPECT was 81%. We concluded that the IMT-SPECT is a promising complementary imaging tool for the detection of recurrences of non-astrocytic intracranial tumours and their distinguishing from treatment-induced changes. The limitation of the IMT-SPECT is its low sensitivity for the detection of small lesions. 相似文献
39.
Baor L Bar-David J Blickstein I 《International journal of fertility and women's medicine》2004,49(1):13-18
OBJECTIVE: To examine the effect of mode of conception (spontaneous versus induced) on parenting stress, psychological well-being and marital quality during the transition to parenthood among parents of twins. METHODS: The Parenting Stress Index was assessed in 37 parents of twins conceived by assisted reproductive technologies (ART) and compared to that of 38 controls who conceived spontaneously. RESULTS: First-time parents after assisted reproduction experienced significantly higher levels of parenting stress than parents who conceived spontaneously (89.3 vs 72.8). Primiparas following assisted reproduction score lower on psychological well-being than do controls. The two study groups did not differ in their perception of marital quality. In addition, ART primiparous mothers experience higher levels of parenting stress and lower levels of psychological well-being in comparison to primiparous mothers who conceived spontaneously. CONCLUSIONS: The transition to parenthood following assisted reproduction is demanding for both parents of twins. In particular, first-time mothers may require qualified emotional support to facilitate adjustment to twin parenthood. 相似文献
40.