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61.
Purpose
This article aims to provide an overview of how spinal deformities can alter normal spine and thoracic cage growth. 相似文献62.
63.
Roncaroli F Nosé V Scheithauer BW Kovacs K Horvath E Young WF Lloyd RV Bishop MC Hsi B Fletcher JA 《Journal of neurosurgery》2003,99(2):402-408
The authors report on two gonadotropic carcinomas of the adenohypophysis that occurred in a55-year-old man (Case 1) and a 53-year-old woman (Case 2), with signs of mass effect and amenorrhea, respectively. Both lesions were macroadenomas. The tumor in Case 1 metastasized to dura mater, skull, nasal sinus, and larynx 2 years after patient presentation, whereas that in Case 2 spread to vertebral bodies and ribs after a 19-year latency. Histologically, the primary, recurrent, and metastatic lesions in Case 1 featured brisk mitotic activity and high MIB-1 levels as well as p53 labeling indices. Immunoreactivity for HER-2/neu was assessable only in rare neoplastic cells of the second recurrence and in 80% of cells of the dural metastasis. Low-level HER-2/neu gene amplification was evident in the recurrent tumors and metastasis. The sellar and metastatic tumors in Case 2 resembled benign gonadotropic adenoma with oncocytic change; p53 accumulation, HER-2/neu overexpression, and HER-2/neu gene amplification were not present. The results indicate that low-level amplification of the HER-2/neu gene might be associated with pituitary carcinomas in which more aggressive behavior is seen. Further studies are needed to determine whether HER-2/neu plays a role in the pathogenesis of pituitary carcinoma. 相似文献
64.
Comparison of computed tomographic angiography with digital subtraction angiography in the diagnosis of cerebral aneurysms: a meta-analysis 总被引:34,自引:0,他引:34
OBJECTIVE: To compare a novel diagnostic radiological technique, computed tomographic angiography (CTA), with the standard method, namely digital subtraction angiography (DSA), in the diagnosis of cerebral aneurysms. METHODS: A comprehensive search of the world literature on CTA was performed. Articles that reported on prospective comparisons of CTA and DSA in the evaluation of patients suspected of harboring cerebral aneurysms were selected for data extraction. Suitable statistical methods were applied to the extracted data for meta-analysis. RESULTS: Twenty-one references met the criteria for use in the meta-analysis. Unweighted calculations based on data for 1251 patients resulted in a sensitivity of 0.933 (93.3%; range, 75.4-100%) and a specificity of 0.878 (87.8%; range, 0-100%). When the studies were weighted for the number of patients in each study, the sensitivity decreased slightly, to 0.927 (92.7%), and the specificity decreased more substantially, to 0.772 (77.2%). CONCLUSION: On the basis of this meta-analysis, DSA remains the standard method. However, many who use CTA have reported it to be as good as or better than DSA in the diagnosis and treatment of cerebral aneurysms, as well as being of less risk and discomfort to their patients and easier and less expensive to perform. 相似文献
65.
Roncaroli F Scheithauer BW Cenacchi G Horvath E Kovacs K Lloyd RV Abell-Aleff P Santi M Yates AJ 《The American journal of surgical pathology》2002,26(8):1048-1055
We describe five primary tumors of the adenohypophysis featuring mitochondrion-rich spindle cells. The patient ages ranged from 53 to 71 years (mean 61.6 years); two were female. All presented with panhypopituitarism. Two also had visual field defect. On neuroimaging all tumors showed suprasellar extension and were indistinguishable from pituitary adenoma. None showed imaging or operative evidence of dural involvement. All were gross totally removed: four by transsphenoidal surgery and one by frontal craniotomy. Follow-up ranged from 2 to 68 months (mean 35.4 months). No recurrences were noted. The clinical workup was noncontributory in all but two patients: one (case no. 4) with an oncocytic thyroid adenoma and another (case no. 5) with squamous carcinoma of both the uterine cervix and of vocal cord. Histologically, the five tumors were composed mainly of fascicles of spindle cells with eosinophilic, granular cytoplasm. Mitoses were rare and necrosis was absent. Neoplastic cells were immunoreactive for vimentin, epithelial membrane antigen, S-100 protein, and galectin-3. Stains for pituitary hormones, synaptophysin, chromogranin, glial fibrillary acidic protein, cytokeratin CAM5.2, smooth muscle actin, CD34, and CD68 were negative. No thyroglobulin immunoreactivity was noted in the tumor of case no. 4. Ultrastructurally, the neoplastic cells contained numerous mitochondria with lamellar cristae. The neoplastic cells were linked by intermediate junctions and desmosomes. No secretory granules were noted. The histologic, immunohistochemical, and fine structural features of these tumors were unlike those of pituitary adenoma or any other primary sellar tumor. A derivation from adenohypophyseal folliculostellate cells is suggested. 相似文献
66.
Niccolò?AllieviEmail author Asaf?Harbi Marco?Ceresoli Giulia?Montori Elia?Poiasina Federico?Coccolini Michele?Pisano Luca?Ansaloni 《World journal of surgery》2017,41(11):2697-2705
Objective
The aim of the present study was to compare the outcomes of conservative versus surgical treatment for acute appendicitis.Background
Although acute appendicitis is a common disease, great debate exists regarding the appropriate management of patients. Conservative treatment has shown positive results in several RCTs, eliciting questions about indications to surgery, therapeutic appropriateness and ethical conduct.Methods
Data were prospectively collected; a Propensity Score-based matching method was implemented in order to reduce bias arising from characteristics of the patients; a proportion of patients (69 in total) were excluded to obtain two comparable groups of study (1a). Main outcomes of the study were: failure rate, in-hospital length of stay (at first admission and cumulative), post-discharge absence from work. Within the medical group, failure was defined as the necessity for appendectomy after conservative treatment, while it was identified with complications and negative appendectomy within the surgical group (Failure 1). In parallel, an additional definition of failure was proposed (Failure 2) and excluded negative appendectomy from the reasons for failure within the surgical group (5b).Results
The failure rate for the conservative treatment resulted to be inferior, as compared to the surgical treatment (16.5 vs. 28.4%, OR 0.523 p = 0.019), considering negative appendectomy as a reason for failure. When excluding negative appendectomy from the definition of failure, medical and surgical treatment appeared to perform equally (failure rate: 16.5 vs. 18.3%, OR 1.014 p = 0.965). Patients managed conservatively showed to have a shorter length of stay at first admission than the patients who underwent appendectomy (3.11 vs. 4.11 days, β = ?0.628 days, p < 0.0001). A lower number of lost work days after discharge resulted from a conservative approach (6 vs. 14.64 days, β = ?8.7 days, p < 0.0001).Conclusions
Considering each outcome as part of a wide-angle analysis, the conservative management of acute appendicitis resulted to be safe and effective in the selected group of patients. In terms of failure rate, the medical treatment resulted to perform as effectively as surgical treatment, if negative appendectomy was excluded from failure, or better, when negative appendectomy was included in the definition of failure. A diminished length of stay during the first admission and a reduced number of lost work days were evident with a conservative approach. The comparison between medical and surgical treatment for acute appendicitis requires a change in perspective, from a spare ‘effectiveness analysis’ to a more thorough ‘appropriateness analysis’: in the present study, the conservative treatment showed to address the clinical requirements in terms of therapeutic appropriateness. Although acute appendicitis is considered a ‘surgical disease’, increasing evidence supports the effectiveness and safety of a conservative approach for selected groups of patients.67.
Rodolfo Milani Matteo Frigerio Federico Spelzini Stefano Manodoro 《International urogynecology journal》2017,28(5):789-791
Introduction and hypothesis
Uterine-sparing procedures could be attractive in patients concerned about fertility preservation and corporeal image changes. Transvaginal uterosacral ligaments (USLs) hysteropexy can provide a mesh-free technique for uterine suspension. This video is intended to serve as a tutorial for surgical steps.Methods
A 38-year-old woman with symptomatic stage III POP desired preserving fertility. After proper counseling, the patient was admitted for vaginal hysteropexy through bilateral high USL suspension according to the featured technique.Results
Prolapse repair was successfully achieved without complications. We had already published a series of 20 cases that confirmed that transvaginal USLs hysteropexy is a promising technique for correcting genital prolapse with uterus preservation.Conclusion
Transvaginal USLs hysteropexy provides a feasible technique for apical support without the use of prosthetic material. This procedure could be attractive to women who desire a uterine-sparing surgical option.68.
Numerical Stability Analysis for a Stationary and Translating Droplet at Extremely Low Viscosity Values Using the Lattice Boltzmann Method Color-Gradient Multi-Component Model with Central Moments Formulation 下载免费PDF全文
Karun P. N. Datadien Gianluca Di Staso & Federico Toschi 《Communications In Computational Physics》2023,33(1):330-348
Multicomponent models based on the Lattice Boltzmann Method (LBM)
have clear advantages with respect to other approaches, such as good parallel performances and scalability and the automatic resolution of breakup and coalescence
events. Multicomponent flow simulations are useful for a wide range of applications,
yet many multicomponent models for LBM are limited in their numerical stability and
therefore do not allow exploration of physically relevant low viscosity regimes. Here
we perform a quantitative study and validations, varying parameters such as viscosity,
droplet radius, domain size and acceleration for stationary and translating droplet simulations for the color-gradient method with central moments (CG-CM) formulation, as
this method promises increased numerical stability with respect to the non-CM formulation. We focus on numerical stability and on the effect of decreasing grid-spacing,
i.e. increasing resolution, in the extremely low viscosity regime for stationary droplet
simulations. The effects of small- and large-scale anisotropy, due to grid-spacing and
domain-size, respectively, are investigated for a stationary droplet. The effects on numerical stability of applying a uniform acceleration in one direction on the domain,
i.e. on both the droplet and the ambient, is explored into the low viscosity regime, to
probe the numerical stability of the method under dynamical conditions. 相似文献
69.
Umberto Capitanio Federico Deho’ Paolo Dell’Oglio Alessandro Larcher Paolo Capogrosso Alessandro Nini Cristina Carenzi Massimo Freschi Alberto Briganti Andrea Salonia Francesco Montorsi Roberto Bertini 《World journal of urology》2016,34(8):1139-1145