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11.

Purpose

To profile the clinical presentation, subtype distribution, and treatment results of sarcomas of the head and neck at a single tertiary academic center over an 11-year period.

Materials and methods

A retrospective review was performed by examining the records and reviewing the pathology of 186 patients with head and neck sarcomas treated at UCLA Medical Center from 2000 to 2011.

Results

The mean age of the study population was 49 ± 22 years. 58% of the patients were male and 42% were female. Median duration of follow-up for the entire group was 18.5 months. The most common presenting symptom was a mass lesion in 59.9% of patients. The nasal cavity/sinus was the most common presenting site seen in 22% of patients. Solitary fibrous tumor/hemangiopericytoma was the most common subtype. 15% of patients had evidence of prior radiation exposure. 26.3% of tumors were greater than 5 cm and 35.5% were high-grade. Margins were positive in 31.2% of patients. Lymph node metastasis was rare at 6.5%. Perineural invasion was identified in 6.5%. Among all subtypes, 5-year recurrence-free survival and overall survival were 50% and 49%, respectively. Multivariate analysis demonstrated that grade and margin status were predictors of recurrence-free survival while grade and age affected overall survival.

Conclusions

Head and neck sarcomas are a rare entity frequently presenting as a mass lesion. In our series, lesions tended to be high-grade with a significant portion of surgical specimens having positive margins. Grade and margin status were the most important predictors of survival.  相似文献   
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The isolation of a human cDNA encoding the multifunctional protein containing GAR synthetase, AIR synthetase, and GAR transformylase by functional complementation of purine auxotrophy in yeast has been reported. Chinese hamster ovary (CHO) cell mutant purine auxotrophs deficient in GAR synthetase (AdeC) or AIR synthetase plus GAR transformylase (AdeG) activities were transfected with this human GART cDNA subcloned into a mammalian expression vector. This restored 49–140% of the activities of GAR synthetase, AIR synthetase, and GAR transformylase in transfected cells when compared to wild-type CHO K1 parental cells. Study of one stably expressing transfectant, AdeC2, revealed that the human GART cDNA was incorporated into the CHO genome. The enzyme activities appear to be associated with an expressed protein of 110 kDa, very similar to that of purified human GART trifunctional enzyme. The AdeC mutant shows reduced amounts of GART mRNA compared to CHO K1 and a protein of apparently reduced size, results consistent with the purine requirement and enzyme deficiency observed in the mutant. These experiments provide definitive evidence that the human GART cDNA encodes and can direct the production of active human GART trifunctional protein in mammalian cells. They also provide important evidence that the AdeC and AdeG mutants of CHO cells are defective in this gene.  相似文献   
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A cohesive multidisciplinary team approach is key in the management of HIV in pregnancy. The primary aim is to prevent transmission to the neonate but also to support the mother in any issues arising from her pre-existing, or new, diagnosis of HIV. Specialist advice should be sought, wherever possible.Key areas discussed in this review include antenatal management of the mother (particularly pharmacological management), obstetric management, pharmacological treatment for the neonate and infant feeding. Due to progress made in both in HIV testing, and in the way all patients with HIV in the UK are managed over the last few decades, most women who present with HIV in pregnancy are aware of their diagnosis and on treatment. However, it is not entirely uncommon for women to be diagnosed in pregnancy and it is these cases that present the greater challenge. The cases in this review cover the most common scenarios encountered.  相似文献   
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Background  

A key feature of a good general practice consultation is that it is patient-centred. A number of verbal and non-verbal behaviours have been identified as important to establish a good relationship with the patient. However, the use of the computer detracts the doctor's attention away from the patient, compromising these essential elements of the consultation. Current methods to assess the consultation and the influence of the computer on them are time consuming and subjective. If it were possible to measure these quantitatively, it could provide the basis for the first truly objective way of studying the influence of the computer on the consultation.  相似文献   
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Ho SF  Reuser T 《Ophthalmology》2007,114(1):197-8; author reply 198-9
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20.
Torticollis associated with positional plagiocephaly: a growing epidemic   总被引:1,自引:0,他引:1  
The primary study aim was to identify characteristics of torticollis associated with plagiocephaly without synostosis (PWS) and to differentiate this from other forms of torticollis. The three commonest causes of infantile torticollis are idiopathic muscular causes such as sternocleidomastoid fibrosis, structural anomalies in the cervical vertebrae, and neurologic or ocular causes, such as certain types of strabismus. Recently, several units have reported increasing numbers of babies presenting with head tilt and reduced range of cervical motion, a form of torticollis apparently associated with PWS and unrelated to the etiologies enumerated above. A secondary aim was to identify local trends in referral patterns over the preceding 3 years. This was a retrospective review of 159 children attending a secondary referral center for management of positional plagiocephaly or torticollis. The data was collected in a university-affiliated child development clinic, and the records of one of three similar, community-based outpatient clinics, staffed by physical therapists and working in conjunction with our tertiary craniofacial surgery center were analyzed by medical staff. There was a persistent escalation in referrals for both PWS and associated torticollis (ie, not attributable to 1 of the 3 causes mentioned) over the study period. Anatomic and clinical features of PWS-associated torticollis were characterised and contrasted with the classic forms of torticollis. Current treatment strategies are outlined and discussed. Torticollis can predispose to PWS, but in a large proportion of our cases of PWS, torticollis appears to develop secondary to plagiocephaly, and the number of presentations is escalating.  相似文献   
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