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81.
From March 2009 to May 2009, 24 carbapenem-resistant Klebsiella pneumoniae isolates were recovered from 16 patients hospitalized in an Italian intensive care unit (ICU). All isolates contained KPC-3 carbapenemase and belonged to a single pulsed-field gel electrophoresis (PFGE) clone of multilocus sequence type 258 (designated as ST258). A multimodal infection control program was put into effect, and the spread of the KPC-3-producing K. pneumoniae clone was ultimately controlled without closing the ICU to new admissions. Reinforced infection control measures and strict monitoring of the staff adherence were necessary for the control of the outbreak.  相似文献   
82.
Study ObjectiveTo demonstrate the importance of planning all the steps of laparoscopic myomectomy, including incision, techniques to reduce blood loss, and suturing.DesignStep-by-step video demonstration of the technique, with narration in the background. The video was approved by the local institutional review board.SettingLive surgery at Hospital PIO XII, Institute for Research into Cancer of the Digestive System and American Institute of Telesurgery, Barretos.InterventionsWe describe a case of a 33-year-old woman with no pregnancy and diagnosed with endometriosis and chronic pelvic pain associated with a 5-cm posterior transmural myoma. We performed a laparoscopic myomectomy, with temporary clipping of the uterine arteries associated with the treatment of endometriosis lesions. Specimen extraction was performed inside a bag [1]. The patient was discharged the next day with no complications. Ten months after the procedure, the patient reported that there was no pain, and that her menses were normal.ConclusionThe laparoscopic approach remains the gold standard for myomectomy [2]. Planning the steps before execution is fundamentally important to ensure the security of the procedure. A seromuscularis baseball suture associated with figure-of-8 knotting with an H3H2 sequence at the internal layers seems to be an adequate technique for myometrium closure [3]. Choosing the correct angle for the incision, clipping the uterine artery, and developing the suture in 2 layers results in less bleeding, reduced operating time, decrease in hospital length of stay, and fewer complications.  相似文献   
83.
 The effects of repetitive transcranial stimulation (rTMS) on brain activity remain unknown. In healthy subjects, we studied the effects of rTMS on the duration of the cortical silent period (SP). Repetitive stimuli were delivered with a Cadwell High Speed Magnetic Stimulator and a figure-of-eight coil placed over the hand motor area. rTMS was delivered in trains of 11 or 20 stimuli at frequencies of 3 and 5 Hz and at stimulation intensities of 110 and 120% of motor threshold. The SP was recorded from the forearm muscles during a voluntary contraction (20% of maximum effort). rTMS delivered at a frequency of 3 and 5 Hz and intensities of 110 and 120% motor threshold prolonged the duration of the SP, without modifying either the size or the latency of the muscle-evoked potentials (MEP). A conditioning train of 11 stimuli at 3 Hz had no effect on the duration of the SP evoked by a single magnetic shock delivered 600 ms after the train. These findings show that rTMS increases the duration of the cortical SP, but does so only during the train of stimuli. rTMS probably changes the duration of the SP by facilitating cortical inhibitory interneurons. Received: 4 December 1997 / Accepted: 11 August 1998  相似文献   
84.
BACKGROUND: Insulin receptor substrate 1 (IRS-1), a cytoplasmic protein transmitting signals from the insulin and insulin-like growth factor 1 receptors, has been implicated in breast cancer. Previously, it was reported that IRS-1 can be translocated to the nucleus and modulate oestrogen receptor alpha (ERalpha) activity in vitro. However, the expression of nuclear IRS-1 in breast cancer biopsy specimens has never been examined. AIMS: To assess whether nuclear IRS-1 is present in breast cancer and non-cancer mammary epithelium, and whether it correlates with other markers, especially ERalpha. Parallel studies were carried out for the expression of cytoplasmatic IRS-1. METHODS: IRS-1 and ERalpha expression was assessed by immunohistochemical analysis. Data were evaluated using Pearson's correlation, linear regression and receiver operating characteristic analysis. RESULTS: Median nuclear IRS-1 expression was found to be low in normal mammary epithelial cells (1.6%) and high in benign tumours (20.5%), ductal grade 2 carcinoma (11.0%) and lobular carcinoma (approximately 30%). Median ERalpha expression in normal epithelium, benign tumours, ductal cancer grade 2 and 3, and lobular cancer grade 2 and 3 were 10.5, 20.5, 65.0, 0.0, 80 and 15%, respectively. Nuclear IRS-1 and ERalpha positively correlated in ductal cancer (p<0.001) and benign tumours (p<0.01), but were not associated in lobular cancer and normal mammary epithelium. In ductal carcinoma, both nuclear IRS-1 and ERalpha negatively correlated with tumour grade, size, mitotic index and lymph node involvement. Cytoplasmic IRS-1 was expressed in all specimens and positively correlated with ERalpha in ductal cancer. CONCLUSIONS: A positive association between nuclear IRS-1 and ERalpha is a characteristic for ductal breast cancer and marks a more differentiated, non-metastatic phenotype.  相似文献   
85.
Obesity is a major threat to public health worldwide, and there is now mounting evidence favoring a role for the central nervous system (CNS) in weight control. A causal relationship has been recognized in both monogenic (e.g., BDNF, TRKB, and SIM1 deficiencies) and syndromic forms of obesity [e.g., Prader–Willi syndrome (PWS)]. Syndromic obesity arising from chromosomal abnormalities, that typically also affect learning and development, are often associated with congenital malformations and behavioral characteristics. We report on nine unrelated patients with a diagnosis of learning disability and/or developmental delay (DD) in addition to obesity that were found to have copy number variants (CNVs) by single nucleotide polymorphism array‐based analysis. Each patient also had a distinct and complex phenotype, and most had hypotonia and other neuroendocrine issues, such as hyperphagia and hypogonadism. Molecular and clinical characterization of these patients enabled us to determine with confidence that the CNVs we observed were pathogenic or likely to be pathogenic. Overall, the CNVs reported here encompassed a candidate gene or region (e.g., SIM1) that has been reported in patients associating obesity and DD and/or intellectual disability (ID) and novel candidate genes and regions. © 2013 Wiley Periodicals, Inc.  相似文献   
86.
The organization and pattern of cutaneous reflex modulation is unknown during rhythmic cyclical movements of the human upper limbs. On the assumption that these cyclic arm movements are central pattern generator (CPG) driven as has been suggested for leg movements such as walking, we hypothesized that cutaneous reflex amplitude would be independent of electromyographic (EMG) muscle activation level during rhythmic arm movement (phase-dependent modulation, as is often the case in the lower limb during locomotion). EMG was recorded from eight muscles crossing the human shoulder, elbow, and wrist joints while whole arm rhythmic cyclical movements were performed. Cutaneous reflexes were evoked with trains of electrical stimulation delivered at non-noxious intensities (approximately 2 x threshold for radiating paresthesia) to the superficial radial nerve innervating the lateral portion of the back of the hand. Phasic bursts of rhythmic muscle activity occurred throughout the movement cycle. Rhythmic EMG and kinematic patterns were similar to what has been seen in the human lower limb during locomotor activities such as cycling or walking: there were extensive periods of reciprocal activation of antagonist muscles. For most muscles, cutaneous reflexes were modulated with the movement cycle and were strongly correlated with the movement-related background EMG amplitude. It is concluded that cutaneous reflexes are primarily modulated by the background muscle activity during rhythmic human upper limb movements, with only some muscles showing phase-dependent modulation.  相似文献   
87.
OBJECTIVE: To evaluate the prevalence and scan interpretation criteria useful in identifying non-tumoural F-FDG focal uptakes (potential pitfalls) in patients who had been previously treated for a malignant lymphoma studied by positron emission tomography (PET). MATERIALS: Nine hundred and ninety-six consecutive PET scans obtained in 706 patients with malignant lymphoma were reviewed. All patients had been previously treated by first-line chemo-radiotherapy, plus surgery when required, and were then studied by FDG PET to investigate suspected recurrence at doubtful or inconclusive conventional radiological imaging (ultrasound, computed tomography, magnetic resonance imaging). PET was obtained with patients in the fasted condition and after i.v. injection of 370 MBq of F-FDG; imaging was acquired 60-90 min later. In patients with focal FDG uptake the final diagnosis was reached on the basis of histological findings or long-term follow-up. RESULTS: Thirty-one of 134 PET scans (23.1%) showing focal FDG uptake were diagnosed as non-tumoural radiotracer uptake, related to the presence of brown fat in seven cases, thymic hyperplasia in five, muscles contraction in four, lymph node unspecific inflammation in four, mediastinal/pulmonary unspecific inflammation in four, gastritis in two, colitis in two, bacterial abscess in one, lactating breast in one, and herpes zoster in one. Each of the above cited situations has been reported in the literature, generally in the form of sporadic reports, as a potential cause of misinterpretation (false positive) in reading a PET scan with the potential for incorrect patient management. An accurate diagnosis in these patients was important for the following therapeutic decision making. CONCLUSIONS: In the whole series of patients with treated malignant lymphoma, the prevalence of non-tumoural FDG focal uptake during follow-up was relatively low (3.1%); conversely, it was relatively high when considering the sub-group of 'positive' PET only (23.1%). The importance of knowing these situations in order to avoid misinterpretation in reading PET scans needs to be emphasized. In this light, an accurate patient's history and a skilful nuclear medicine physician are very important factors. For the same purpose, it is reasonable to think that the use of hybrid PET/CT tomographs could also play an important role in helping to identify non-tumoural FDG focal uptake.  相似文献   
88.
Battista G  Zompatori M  Poletti V  Canini R 《La Radiologia medica》2003,106(5-6):445-51; quiz 452-3
Systemic autoimmune diseases include different forms of vasculitides and collagen diseases. Among collagen diseases, the rarer entities include: Sj?gren syndrome, dermatopolymyositis, ankylosing spondylitis, relapsing polychondritis and mixed connective tissue disorders. The diagnosis of these entities requires an integrated multidisciplinary approach. The radiological findings of collagen diseases are well known; however, the introduction of HRCT studies provides additional information and enable an early diagnosis. The more common thoracic manifestations of collagen diseases include interstitial pneumonia (usual, nonspecific and lymphocytic), bronchiolitis obliterans organizing pneumonia (BOOP), airway diseases (bronchiectasis, obliterative and constrictive bronchiolitis, follicular bronchiolitis), pleural abnormalities, diaphragmatic dysfunction, apical fibrosis. The aim of this pictorial essay is to present the main radiological and HRCT patterns related to the less common collagen diseases.  相似文献   
89.
Purpose The purpose of this work was the development of an orthotopic model of osteosarcoma based on luciferase-expressing tumour cells for the in vivo imaging of multidrug resistance (MDR) with 99mTc-sestamibi. Methods Doxorubicin-sensitive (143B-luc+) and resistant (MNNG/HOS-luc+) osteosarcoma cell lines expressing different levels of P-glycoprotein and carrying a luciferase reporter gene were inoculated into the tibia of nude mice. Local tumour growth was monitored weekly by bioluminescence imaging and X-ray. After tumour growth, a 99mTc-sestamibi dynamic study was performed. A subset of animals was pre-treated with an MDR inhibitor (PSC833). Images were analysed for calculation of 99mTc-sestamibi washout half-life (t 1/2), percentage washout rate (%WR) and tumour/non-tumour (T/NT) ratio. Results A progressively increasing bioluminescent signal was detected in the proximal tibia after 2 weeks. The t 1/2 of 99mTc-sestamibi was significantly shorter (p < 0.05) in drug-resistant MNNG/HOS-luc+ tumours (t 1/2 = 87.3 ± 15.7 min) than in drug-sensitive 143B-luc+ tumours (t 1/2 = 161.0 ± 47.4 min) and decreased significantly with PSC833 (t 1/2 = 173.0 ± 24.5 min, p < 0.05). No significant effects of PSC833 were observed in 143B-luc+ tumours. The T/NT ratio was significantly lower (p < 0.05) in MNNG/HOS-luc+ tumours than in 143B-luc+ tumours at early (1.55 ± 0.22 vs 2.14 ± 0.36) and delayed times (1.12 ± 0.11 vs 1.62 ± 0.33). PSC833 had no significant effects on the T/NT ratios of either tumour. Conclusion The orthotopic injection of tumour cells provides an animal model suitable for functional imaging of MDR. In vivo bioluminescence imaging allows the non-invasive monitoring of tumour growth. The kinetic analysis of 99mTc-sestamibi washout provides information on the functional activity of MDR related to P-glycoprotein expression and its pharmacological inhibition in osteosarcoma.  相似文献   
90.
BACKGROUND: Recent technical improvements have led the way to a resurgence of the single-incision approach for repair of distal biceps tendon injuries. There has been no biomechanical evaluation of all these techniques with comparison to the standard 2-incision bone tunnel technique. HYPOTHESIS: There will be no difference under cyclic loading and ultimate failure between the 2-incision bone tunnel technique, suture anchor repair, interference screw, and EndoButton techniques for the repair of distal biceps tendon ruptures. STUDY DESIGN: Controlled laboratory study. METHODS: Sixty-three fresh-frozen cadaveric elbows were randomly assigned to 4 treatment groups (bone tunnel, EndoButton, suture anchor, interference screw). Cyclic loading was then performed from 0 degrees to 90 degrees at 0.5 Hz for 3600 cycles with a 50-N load. A differential variable reductance transducer was placed between the radius and distal tendon to determine displacement. The construct was then pulled to failure at 120 mm/min. RESULTS: A multiple analysis of variance revealed no statistically significant difference for displacement among the 4 repair techniques. Displacement using the bone tunnel was 3.55 mm, EndoButton was 3.42 mm, suture anchor was 2.33 mm, and interference screw was 2.15 mm. There was a statistically significant greater load to failure with EndoButton (440 N) than suture anchor (381 N), bone tunnel (310 N), or interference screw (232 N) (P < .001). CONCLUSION: The EndoButton technique had the highest load to failure. CLINICAL RELEVANCE: These data demonstrate the EndoButton to be the strongest repair technique, with no failures during cycling at physiologic loads and with the largest load to failure. These findings are important in maximizing surgical results and stability and suggest that the construct can tolerate early postoperative active range of motion.  相似文献   
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