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71.
72.
Parameswaran Rajeev Tarek Ezzat Mark Slade Gregory Paul Sadler Radu Mihai 《World journal of surgery》2013,37(11):2589-2593
Background
Anaplastic thyroid carcinoma (ATC) is the most aggressive form of thyroid cancer and it has an extremely poor prognosis. Rapid airway compromise is the main cause of death in patients with ATC.Methods
The present study is based on a retrospective review of clinical data of patients with ATC treated over the last decade in a tertiary referral center.Results
Between January 1998 and December 2010, 31 patients (13 males: 18 females) with a mean age of 74 years (range: 54–90 years) had a diagnosis of ATC made on fine-needle aspiration (n = 29) or biopsy (n = 2). Eight patients underwent total thyroidectomy and lymph node dissection, and five patients had attempted surgery but the procedure was abandoned because of inoperability. Airway compromise was clinically apparent in 11 patients. Five patients had tracheal stents inserted, with a median survival of 2 months (range: 1–36 months). In the whole cohort, 29 patients died of the disease, with a mean survival of 7 months (range: 1–36 months).Conclusions
Survival of patients with undifferentiated thyroid cancer is severely compromised by airway obstruction. Palliation with tracheal stenting can rescue catastrophic airway obstruction but offers minimal survival benefit. 相似文献73.
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75.
During the process of evolution, segmented structures like heart and kidneys appeared earlier than vertebral column. Single piece notochord was transformed into segmented vertebral column. Ribs followed the segmented vertebral column but preceded the fore limbs in evolution. Segmentation is the underlying principle of the body plan even in annelids and arthropods. In these animals apart from vertebral column; segmentation is obvious in other structures like kidneys and heart. Somewhere on the temporal axis of evolution--vertebral column, heart and kidneys have evolved together; and have shared the genetic control of embryological morphogenesis. Mutations or micro-evolution in homeotic--Hox--genes led to macro evolution and a sudden change in morphology, when six-legged insects diverged from crustacean-like arthropod ancestors with multiple limbs. The control of embryonic morphology has been highly conserved in evolution between vertebrates and invertebrates and Hox genes occupy a central role in the scheme of molecular control of early morphogenesis. Mutations affecting regulatory genes, including those containing homeobox sequences, have been important. Malformations and association like VACTERL can be rationally explained considering the genetic and evolutional mechanisms controlling morphogenesis. 相似文献
76.
Thermal therapy, Part III: ablation techniques 总被引:2,自引:0,他引:2
Habash RW Bansal R Krewski D Alhafid HT 《Critical reviews in biomedical engineering》2007,35(1-2):37-121
Ablative treatments are gaining increasing attention as an alternative to standard surgical therapies, especially for patients with contraindication or those who refuse open surgery. Thermal ablation is used in clinical applications mainly for treating heart arrhythmias, benign prostate hyperplasia, and nonoperable liver tumors; there is also increasing application to other organ sites, including the kidney, lung, and brain. Potential benefits of thermal ablation include reduced morbidity and mortality in comparison with standard surgical resection and the ability to treat nonsurgical patients. The purpose of this review is to outline and discuss the engineering principles and biological responses by which thermal ablation techniques can provide elevation of temperature in organs within the human body. Because of the individual problems associated with each type of treatment, a wide range of ablation techniques have evolved including cryoablation as well as ultrasound, radiofrequency (RF), microwave, and laser ablation. Aspects of each ablation technique, including mechanisms of action, equipment required, selection of eligible patients, treatment techniques, and patient outcomes are presented, along with a discussion of limitations of the techniques and future research directions. 相似文献
77.
Kulkarni-Kale U Ojha J Manjari GS Deobagkar DD Mallya AD Dhere RM Kapre SV 《Virology》2007,359(2):436-446
Mumps is an acute infectious disease caused by mumps virus, a member of the family Paramyxoviridae. With the implementation of vaccination programs, mumps infection is under control. However, due to resurgence of mumps epidemics, there is a renewed interest in understanding the antigenic diversity of mumps virus. Hemagglutinin-neuraminidase (HN) is the major surface antigen and is known to elicit neutralizing antibodies. Mutational analysis of HN of wild-type and vaccine strains revealed that the hypervariable positions are distributed over the entire length with no detectable pattern. In the absence of experimentally derived 3D structure data, the structure of HN protein of mumps virus was predicted using homology modeling. Mutations mapped on the predicted structures were found to cluster on one of the surfaces. A predicted conformational epitope encompasses experimentally characterized epitopes suggesting that it is a major site for neutralization. These analyses provide rationale for strain specificity, antigenic diversity and varying efficacy of mumps vaccines. 相似文献
78.
Gurpreet Kaur Varsha Dogra Rajeev Kumar Sandeep Kumar Gaurav Bhanjana Neeraj Dilbaghi Nitin Kumar Singhal 《International journal of pharmaceutics》2018,535(1-2):95-105
In the present study, we have synthesized mixed cuprous/copper oxide nanosuspensions by metallosurfactant based microemulsion technique. Three metallosurfactants were synthesized which includes two non-ionic double chained metallosurfactants with C12, C16 chains with coordinated copper i.e. Cudda and Cuhexa, respectively. Another cationic double chained metallosurfactant with loosely bound metal (Cuctac) was also prepared. The prepared metallocomplexes were characterized using FTIR, elemental analysis, and NMR. The effect of the position of metallosurfactant in microemulsion on the fabrication and properties of nanosuspensions was elucidated. In this method, no external reducing agent and capping agent were added and tween 80 acted both as reducing and stabilizing agent for the nanoparticles. The synthesized nanoparticles were characterized and it was observed that mixed copper and cuprous oxide particles are present in colloidal suspension for all the three studied metallosurfactants. The kinetics of formation of mixed copper/cuprous oxide nanosuspensions (Ns) and their stability was estimated using Uv-visible spectroscopy. Further, the binding and interactions of copper nanosuspensions with calf Thymus DNA (CT-DNA) were assessed using Uv–vis spectroscopy, circular dichroism and gel electrophoresis. Additionally, the antioxidant activity of the Cu Ns was checked using DPPH assay. The role of positive charge on nanoparticles as evaluated from Zeta potential was responsible for DNA affinity. The DNA conformational changes in the presence of nanosuspensions and relevant scavengers were investigated. Further, the anti-proliferative activity of copper Ns was assessed using HeLa cells and Cuhexa derived Ns were proved to be active with highest activity at a low concentration and were nontoxic towards normal cell lines. In summary, this work demonstrates a softer approach for the synthesis of copper nanosuspensions with a size range of 2–5?nm and evaluated the role of type and structure of metallosurfactant on size, stability of particles and anti-proliferative activity. 相似文献
79.
AIM: The purpose of this article is to report a rare case of primary tuberculosis of the tongue. BACKGROUND: Tuberculosis is an infectious, chronic granulomatous disease that can involve almost any organ in the body, but primary lesions are usually confined to the lungs. Oral lesions are an infrequent occurrence in tuberculosis, and tuberculosis of the oral cavity is often a consequence of active pulmonary tuberculosis. Although primary tuberculosis in the oral cavity has been documented, it is a rare occurrence. REPORT: A 42-year-old male patient presented with chief complaints of severe pain and ulceration on the ventrolateral surface of the left side of the tongue, measuring about 1.25 x 1.50 cm with surrounding erythema and induration of one-month duration. The ulcer was initially painless but became painful later with increased severity over time. The sore tongue caused difficulty in eating, drinking, swallowing, and even talking. The patient also complained of malaise for some duration, but there was no history of fever, cough, weight loss, and his bladder-bowel habits were normal. An excisional biopsy differentiated the lesion from squamous cell carcinoma and confirmed the diagnosis. SUMMARY: Even though primary tuberculosis in the oral cavity is a rare finding, it must be included in the differential diagnosis of mucosal lesions. This case provides a clinical example of the importance of this inclusion for the well being of the patient and for the community due to the communicable nature of the disease. 相似文献
80.
Manchikanti L Manchukonda R Pampati V Damron KS McManus CD 《Archives of physical medicine and rehabilitation》2007,88(4):449-455
OBJECTIVE: To evaluate the prevalence of facet joint pain in patients with chronic low back pain (CLBP) after surgical intervention(s). DESIGN: A prospective, nonrandomized, consecutive study. SETTING: An ambulatory interventional pain management setting. PARTICIPANTS: The prevalence of facet joint pain was evaluated in patients with CLBP after various surgical intervention(s) referred to an interventional pain management practice. The sample was derived from 282 patients with persistent CLBP after various surgical intervention(s). Of these, 242 patients consented to undergo interventional techniques. A total of 117 consecutive patients with chronic, nonspecific low back pain, after lumbar surgical intervention(s) were evaluated with controlled, comparative local anesthetic blocks. INTERVENTIONS: Controlled, comparative local anesthetic blocks (1% lidocaine or 1% lidocaine followed by .25% bupivacaine) under fluoroscopic visualization using 0.5mL to block each facet joint nerve. MAIN OUTCOME MEASURES: A positive response was defined as at least 80% reduction of pain with ability to perform previously painful movements. A positive response was considered to be pain relief from the lidocaine block lasting at least 1 hour or at least 2 hours or greater than duration of relief with lidocaine when bupivacaine was used. Controlled, comparative local anesthetic blocks were used to eliminate false-positive results. Valid information is only obtained by performing controlled blocks in the form of comparative local anesthetic blocks, in which, on 2 separate occasions, the same joint is anesthetized by using local anesthetics with different durations of action. If patients obtained appropriate response with both blocks, they were considered a positive. If they obtained appropriate response with lidocaine but not with bupivacaine, they were considered false-positive, whereas if the response was negative with lidocaine, they were considered negative. RESULTS: The prevalence of lumbar facet joint pain in patients with recurrent pain after various surgical intervention(s) was 16% (95% confidence interval, 9%-23%). The false-positive rate with a single block with lidocaine was 49%. CONCLUSIONS: Facet joints are clinically important pain generators in a small but significant proportion of patients with recurrent CLBP after various surgical intervention(s). 相似文献