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61.

Introduction

Fine needle aspiration (FNA) is a safe and quick method of diagnosing superficial lumps, which aids preoperative planning. However, FNA of the parotid gland has not gained the widespread acceptance noted in other head and neck lumps. The aim of this study was to determine the ability of FNA of the parotid gland to differentiate benign and malignant disease, and to determine the impact on surgical outcome.

Methods

A retrospective analysis of 201 consecutive parotid operations with preoperative FNA in a large district hospital in the UK was performed. The diagnostic characteristics were calculated for benign and malignant disease, and the impact on surgical procedure was determined.

Results

In identifying benign disease, FNA has a sensitivity of 85% and a specificity of 76%. In detecting malignant disease, FNA has a sensitivity and specificity of 52% and 92% respectively. A false positive on FNA was associated with a higher incidence of neck dissection.

Conclusions

FNA is a useful diagnostic test. However, owing to low sensitivity, it is necessary to interpret it in the context of all other clinical information.  相似文献   
62.
The initial experience in facial composite tissue allotransplantation has demonstrated that it is surgically feasible, safe, and reproducible. A robust team approach is necessary to warrant successful outcomes. We designed a specific face organ donation that limits facial donation requests followed by synchronous in situ dissection with the internal organs that has proved to be efficient and safe for face and solid organ procurement and transplantation. The first human full face transplantation in our institution was performed on March 27, 2010. The holistic team approach of donation and procurement proved to be effective and reproducible; the recipient showed excellent outcomes at 12 months.  相似文献   
63.

Background

There remains still no clear answer as to whether or not prophylactic central compartment neck dissection (pCCND) is indicated for the treatment of patients with papillary thyroid cancer.

Methods

The published studies, including single cohort, comparative studies and meta-analysis, were critically appraised. Aspects beyond postoperative complications and loco-regional recurrence rates in the analysis, as the impact of pre- and post-ablation thyroglobuline levels, multifocality, bilaterality and additional risk factors for recurrence, were also considered.

Results

Thirty studies and five meta-analyses were assessed. The lack of randomized clinical trials on the subject and the heterogeneity of study populations are the main limiting factors to draw clear conclusions, and a comprehensive list of bias sources has been identified. Recent comparative studies and systematic reviews all associate the pCCND with higher proportions of temporary postoperative hypocalcemia but not with significantly higher permanent hypoparathyroidism, recurrent laryngeal nerve injury or permanent vocal cord paralysis. The risk of recurrence appears to be reduced after pCCND, and the number of patients needed to treat to avoid a recurrence is between 20 and 31.

Conclusions

It is suggested that routine level 6 prophylactic dissections should be risk-stratified. Larger tumours (T3, T4), patients aged 45 years and older or 15 years and younger, male patients, patients with bilateral or multifocal tumours, and patients with known involved lateral lymph nodes could all be candidates for routine unilateral level 6 dissection. The operation should be limited to surgeons who have the available expertise and experience  相似文献   
64.
Neuropathic pain is a condition affecting a significant proportion of the world's population. Many therapeutic drugs have been used. They achieve less than satisfactory results and are associated to common side effects that affect the daily life of patients. Pregabalin is a new drug that has been shown to be effective for treating partial epilepsy and peripheral neuropathic pain in clinical trials. It is a structural, but not functional, analogue of GABA. It acts as a ligand of the alpha2-delta subunit, a protein associated to the voltage-dependent calcium channels. Modulation of these channels decreases calcium entry into nerve endings, resulting in a decreased release of several excitatory neurotransmitters. Pregabalin had a linear pharmacokinetics with little variability between the different subjects. It does not bind to plasma proteins, has no liver metabolism, and is excreted trough the kidneys. Few interactions with other drugs may be expected based on these characteristics. In clinical trials, pregabalin has been shown to be effective in postherpetic neuralgia and painful diabetic neuropathy at doses ranging from 150-600 mg/day. The analgesic effects of pregabalin occur in the first few days of treatment and are sustained over time. Side effects are few; most are transient and well-tolerated by patients, and the treatment discontinuation rate is minimal.  相似文献   
65.
Sensorimotor gating deficits are relevant in schizophrenia and can be measured using prepulse inhibition (PPI) of the startle reflex. It is conceivable that such deficits may hinder the cognitive functions in schizophrenia patients. In this study, using PPI and a neuropsychological battery, we studied this possibility in a group of 23 acute, neuroleptic-free schizophrenia patients and 16 controls. A non-significant decrease in PPI was found in the patients as compared to the controls, as well as significant differences in the performance of Trail A and B in Wisconsin Card Sorting and Digit/Symbol Tests. No statistically significant correlations between PPI and neuropsychological performance were found after the correction for multiple comparisons in any group. Our results suggest that PPI deficits in schizophrenia patients may not contribute to the cognitive deficits typical of that illness, at least in patients with a non-significant PPI decrease.  相似文献   
66.
The PET tracer [11C]5-hydroxytryptophan ([11C]5-HTP), which is converted to [11C]5-hydroxytryptamine ([11C]5-HT) by aromatic amino acid decarboxylase (AADC), is thought to measure 5-HT synthesis rates. But can we measure these synthesis rates by kinetic modeling of [11C]5-HTP in rat? Male rats were scanned with [11C]5-HTP (60 minutes) after different treatments. Scans included arterial blood sampling and metabolite analysis. 5-HT synthesis rates were calculated by a two-tissue compartment model (2TCM) with irreversible tracer trapping or Patlak analysis. Carbidopa (inhibitor peripheral AADC) dose-dependently increased [11C]5-HTP brain uptake, but did not influence 2TCM parameters. Therefore, 10 mg/kg carbidopa was applied in all subsequent study groups. These groups included treatment with NSD 1015 (general AADC inhibitor) or p-chlorophenylalanine (PCPA, inhibitor of tryptophan hydroxylase, TPH). In addition, the effect of a low-tryptophan (Trp) diet was investigated. NSD 1015 or Trp depletion did not affect any model parameters, but PCPA reduced [11C]5-HTP uptake, and the k3. This was unexpected as NSD 1015 directly inhibits the enzyme converting [11C]5-HTP to [11C]5-HT, suggesting that trapping of radioactivity does not distinguish between parent tracer and its metabolites. As different results have been acquired in monkeys and humans, [11C]5-HTP-PET may be suitable for measuring 5-HT synthesis in primates, but not in rodents.  相似文献   
67.
A case report is presented of a rapidly growing congenital nasopharyngeal teratoma (epignathus) in a preterm infant, leading to severe upper airway obstruction. Prenatal diagnosis by ultrasonography did not reveal the condition because the tumour masses were initially small and there was no polyhydramnios. Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period and should be treated surgically.
Conclusion:  Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period.  相似文献   
68.
有机锗化物(二羧乙基锗三氧化物,dicarboxyethenylgermanium sesquioxide简称DCG)系一人工合成的新型化合物,分子式(GeCH_2CH_2COOH)_2O_3,分子量339.18,其中含纯锗42.8%。锗是生物体内非必需微量元素,在自然界及生物体内分布相当广泛。最近Ninomiya  相似文献   
69.
70.
Preferential use of the VH4 Ig gene family by diffuse large-cell lymphoma   总被引:7,自引:2,他引:7  
Hsu  FJ; Levy  R 《Blood》1995,86(8):3072-3082
Ig heavy chain variable region (VH) genes expressed by human diffuse large-cell lymphoma (DLC) and follicular lymphoma (FL) were identified and analyzed with respect to germline gene families. In 67 cases of FL, VH region genes were expressed in a pattern similar to that of normal B cells, with a predominance of the large VH3 gene family being used. In contrast, of the 17 cases of DLC, there was an extremely biased use of VH genes. Of these DLC tumors, 88% expressed genes from the small VH4 gene family; and even among these tumors, there was a limited use of genes, with 11 cases producing Igs derived from the VH4.21 germline gene. Although most of the VH genes expressed by DLC tumor cells contained mutations with respect to their germline counterparts, almost all of these mutations occurred before the clonal expansion of the tumor. This contrasts with our previous findings of ongoing mutations in FL and represents a fundamental difference between these two malignancies. This preferential gene use implies an important role for the VH4 gene family, and specifically for VH4.21, in the genesis of DLC.  相似文献   
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