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1.
Survival of patients with surgically treated malignancy may be adversely affected by blood transfusion. Immune suppression due to transfusion has been implicated but remains unproven. We conducted a study of 240 patients with squamous cell carcinoma of the larynx undergoing laryngectomy to assess the effect of per-operative blood transfusion on survival.  相似文献   
2.
Value of grading squamous cell carcinoma of the head and neck.   总被引:3,自引:0,他引:3  
We report a series of 3,294 patients with squamous cell carcinoma of the head and neck seen by one of us between 1963 and 1990. Two thousand and seven patients had a histologically proven and graded, but previously untreated, squamous cell carcinoma of the mucosal surfaces of the head and neck. These tumors had been graded previously by many different pathologists in many different hospitals, both in the United Kingdom and the United States, as well as continental Europe, over this period. Of the host factors both sex and age were associated with differentiation: 34% of patients less than age 50 had a well-differentiated tumor compared with 44% greater than age 50; 32% of women had a poorly differentiated tumor compared with 26% of men. General condition had no correlation with degree of differentiation. Site was closely associated with grading: well-differentiated tumors were more common in the mouth and larynx and poorly differentiated tumors in the pharynx. Furthermore, of poorly differentiated tumors, 19% arose from areas normally lined by keratinized squamous epithelium, 22% from a nonkeratinized area, 36% from respiratory epithelium, and 45% from areas normally covered by lymphoid epithelium. T stage had no significant correlation with differentiation. However, 46% of patients with poorly differentiated tumors had a nodal metastasis at presentation compared with only 28% of well-differentiated tumors. Distant metastases at presentation were found in 3.4% of poorly differentiated tumors compared with 1.8% of well-differentiated tumors. The survival fell significantly from 33% for well-differentiated tumors to 27% for poorly differentiated tumors. The recurrence rate at the primary site rose from 25% for well-differentiated tumors to 27% for poorly differentiated tumors, and recurrence in the lymph nodes rose from 26% to 30%. Both differences were just significant.  相似文献   
3.
Previous work has suggested that there may be a widespread disturbance of motor control mechanisms in patients with cervical dystonia. In the present study, we used transcranial magnetic stimulation to investigate the topography of the corticomotor projection to the abductor pollicis brevis (APB) muscle in 10 subjects with idiopathic torticollis. Threshold-adjusted stimuli were delivered at multiple scalp sites during a low-level voluntary contraction of the APB, and maps were generated of motor evoked potential amplitude versus scalp site. The cortical maps for the APB on the side opposite to the direction of head rotation were displaced laterally or posteriorly in all subjects and reverted to a more normal position after botulinum toxin injection of the cervical muscles in 5 subjects. The findings point to a reversible reorganisation of the corticomotor representation of the hand on the same side as the sternocleidomastoid (SCM) muscle that is involved in producing the dystonia. These results provide further evidence for the involvement of cortical centres and for a more widespread abnormality of motor control mechanisms in focal dystonia. The findings also support the notion that head turning is chiefly mediated by the hemisphere ipsilateral to the direction of the head rotation by means of a corticomotor projection to the contralateral SCM.  相似文献   
4.
Extracranial paranasal spread of meningiomas is uncommon. We describe the management of four cases, all of which first presented to an oto-rhino-laryngologist for an opinion. We suggest that greater use of modern imaging techniques could lead to earlier diagnosis. The natural history of extracranial spread is relatively benign but the management of regrowth of residual disease is difficult. We therefore suggest radical surgery in the first instance provided that the patients general health and configuration of the tumour allow.  相似文献   
5.
The histopathology of 54 squamous carcinomas of the head and neck was evaluated by qualitative grading and morphometry in order to identify those features which predicted a good response to cisplatinum chemotherapy. The histopathology of 66 cases was correlated with tumour ploidy, determined by flow cytometry of paraffin-embedded material, since a separate study has shown that aneuploid carcinomas respond better to chemotherapy. The degree of differentiation was a poor predictor of ploidy, although diploid carcinomas did show more keratin and less nuclear pleomorphism than aneuploid carcinomas. The prominence of nucleoli in tumour cells and the surface area to volume (s/v) ratio of the tumour islands were the variables most strongly correlated with ploidy, with diploid carcinomas having prominent nucleoli and a low s/v ratio. A good response to chemotherapy was related partly to the architecture of the carcinoma (pushing border and low s/v ratio), and partly to the tumour cells (well differentiated) and the percentage of necrotic tumour. A lack of inflammatory reaction or desmoplasia was associated with a poor response. The results indicate that both subjective and objective histopathological criteria may be used to predict ploidy and the response to cisplatinum chemotherapy of squamous carcinoma of the head and neck. A combination of s/v ratio and the percentage of necrotic tumour can be used to identify a group of patients with a relatively good survival.  相似文献   
6.
Retinoids have many functions in the eye, including, perhaps, the visual guidance of ocular growth. Therefore, we identified where retinoid receptors, binding proteins, and biosynthetic enzymes are located in the ocular tissues of the chick as a step toward discovering where retinoids are generated and where they act. Using antibodies to interphotoreceptor retinoid binding protein (IRBP), cellular retinol binding protein (CRBP), cellular retinoic acid binding protein (CRABP), cellular retinaldehyde binding protein (CRALBP), retinaldehyde dehydrogenase (RALDH), and retinoic acid receptors (RAR and RXR), we localized these proteins to cells in the retina, retinal pigmented epithelium, choroid and sclera of the chick eye. IRBP was detected in the photoreceptor layer and pigmented epithelium; CRBP was in the pigmented epithelium; CRABP was in amacrine and bipolar cells in the retina; CRALBP was in Müller cells, pigmented epithelium, choroid, and fibrous sclera; RALDH was in retinal amacrine cells, pigmented epithelium, and choroid; RAR was in amacrine cells, choroid, and chondrocytes and fibroblasts in the sclera; and RXR was in amacrine and ganglion cells, bipolar cell nuclei, choroid, and chondrocytes. We also found that the growth-modulating toxins colchicine and quisqualate destroyed selectively different subsets of CRABP-containing amacrine cells. We conclude that the distribution of proteins involved in retinoid metabolism is consistent with a role of retinoids not only in phototransduction, but also in maintenance of cellular phenotype and visual guidance of ocular growth.  相似文献   
7.
The distribution of short wavelength-sensitive (SWS or "blue") cone photoreceptors was compared in primates with dichromatic ("red-green colour blind") and trichromatic colour vision. We compared a New World species, the marmoset (Callithrix jacchus), with an Old World species, the macaque monkey (Macaca nemestrina). The SWS cones were identified by their immunoreactivity to an antiserum against the human SWS cone opsin. A single retina from a male capuchin monkey (Cebus apella) also was studied. The SWS cones make up less than 10% of all cone photoreceptors throughout the retina of all animals studied. In marmoset, the peak spatial density of SWS cones is close to 10,000/mm2 at the foveola. In macaque, the peak spatial density of SWS cones, close to 6,000/mm2, is at the fovea, but SWS cones are absent within 50 microm of the centre of the foveola. In both species, the density of SWS cones is higher on the nasal retinal axis than at corresponding eccentricities on the other retinal axes. The SWS cones in macaque are arranged in a semiregular array, but they are distributed randomly in marmoset. There is no difference in the spatial density or local arrangement of SWS cones between dichromatic and trichromatic marmosets. The results suggest that the SWS cone photoreceptor system is subject to different developmental and evolutionary constraints than those that have led to the formation of the red-green photoreceptor systems in primate vision.  相似文献   
8.
Of the 397 patients undergoing total laryngectomy for squamous cell carcinoma by Professor P. M. Stell between 1963 and 1991, 73 are known to have suffered a local recurrence. Of these, 17 were treated by radiotherapy and/or further surgery. Secondary surgery was reserved for selected cases of peristomal and pharyngeal recurrence: of the 35 peristomal recurrences, eight were treated surgically. Previous reports of recurrence after total laryngectomy have focused on the problem of peristomal recurrence. Patients with pharyngeal recurrences can also be treated satisfactorily with microvascular surgical reconstruction techniques. Though rarely curative, secondary total pharyngectomy can be highly palliative and results in little additional morbidity.  相似文献   
9.
10.
OBJECTIVES—To study the role of corticomotorneuronal pathways in primary orthostatic tremor.
METHODS—Transcranial magnetic stimuli at anintensity 10% above the resting motor threshold were delivered overthe leg motor cortex in two patients with primary orthostatic tremorwhile standing still. Electromyographic responses in both tibialisanterior muscles were recorded after 20 stimuli given randomly atintervals of 120 to 180 seconds. Differences between predictedand actual times of occurrence of tremor bursts after the stimuli wereused to calculate a resetting index, with a value of 0 representing no resetting and a value of 1 representing complete resetting.
RESULTS—Transcranial magnetic stimulation evokedEMG responses in both tibialis anterior muscles, followed by transientsuppression of tremor before reappearance of rhythmic EMG activity.Analysis of the timing of tremor bursts from EMG recordings before and after the magnetic stimuli disclosed that the phase of orthostatic tremor could be reset by brain stimulation (mean resetting indices 0.93 and 0.82).
CONCLUSION—The results suggest that a centraloscillator, involving the motor cortex, has a crucial role in eitherthe generation or modulation of orthostatic tremor.

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