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1.
Forty-six (85%) basal cell and eight (15%) squamous cell carcinomas of the eyelids were treated with electron beams between 1963 and 1983. Lesion sizes ranged from microscopic to 4 cm, with 28 lesions larger than 1 cm. Thirty-eight lesions were treated with radiotherapy after incisional biopsy, and 16 were treated after excisional biopsy (specimens showed positive margins). Doses varied from 45 to 72 Gy, with daily fractions ranging from 2.12 to 4.0 Gy. There were six disease recurrences (10.9%): three in the treatment field and three at the treatment margin. Four of six recurrences were subsequently controlled by limited surgical excision and repair with preservation of the eye, whereas the other two required enucleation. Treatment sequelae such as skin atrophy, telangiectasis, and cosmetic results were evaluated in terms of radiotherapy parameters, pretreatment surgery, and size of the lesion. In 44 patients, the overall cosmetic result was judged as good to excellent, five patients had a mild to modest degree of deformity, and five had significant deformity. Such deformity was usually associated with tumor destruction or previous surgery. No major complications were noted.  相似文献   
2.
The aim of this orthopaedic-biomechanical study was to evaluate lower leg muscle function in ankle osteoarthritis (OA) patients and muscle rehabilitation after the implantation of a total ankle replacement (TAR). Patients with a severe unilateral ankle OA were assessed with an orthopaedic and biomechanical examination before and one year after TAR surgery. Visual analogue pain score, American Orthopaedic Foot and Ankle Society (AOFAS) ankle score, ankle range of motion for dorsi- and plantar flexion (ROM DF/PF), and calf circumference difference between affected and contralateral healthy leg were measured. Isometric maximal voluntary torque for ankle dorsiflexion and plantar flexion were measured simultaneously with surface electromyography (EMG; mean frequency and intensity) of the anterior tibial, medial gastrocnemius, soleus, and peroneus longus muscle. Data were compared to a group of age- and gender-matched normal subjects. The mean calf circumference difference between legs did not significantly decrease from preoperative to one year follow-up. The mean dorsiflexion torque and plantar flexion torque of the affected ankle increased significantly. The atrophic muscles were characterized by a reduction of the mean EMG intensity and mean EMG frequency. In the rehabilitation process, the mean EMG intensity recovered and was not significantly different for all muscles, however, not for EMG frequency, which remained low and unchanged. This study reports for the first time in the literature the clinical and biomechanical facts of lower leg muscle atrophy in ankle OA as well as the amount of the muscle rehabilitation after a total ankle replacement. Patients with a symptomatic ankle OA achieve better function with a total ankle replacement; however, one year after the operation neuromuscular and biomechanical deficits may still be present.  相似文献   
3.
: The use of needle-localization breast biopsy (NLBB) for the early diagnosis of breast cancer is common. The therapeutic adequacy of tumor-free margins following NLBB is unknown. We hypothesized that the presence of residual tumor after reexcision (mastectomy, tylectomy, or quadrantectomy) does not depend on the margin status following NLBB. : Retrospective cohort analysis was performed on 890 consecutive NLBBs executed between January 1990 and June 1994. Patients with invasive breast neoplasia were divided into two groups based on the tumor margins after NLBB. Group 1 were the women with positive margins, and group 2 had negative margins. Breast specimens after reexcision were reviewed for evidence of residual invasive carcinoma. : Invasive neoplasia was present in 107 patients (12%). Surgical margins and definitive records of care were avaliable for 96 of them (90%). All 45 patients in group 1 and 38 (75%) of 51 patients in group 2 underwent reexcision of the initial biopsy site (P = 0.36). Residual invasive carcinoma was present in 10 patients (22%) in group 1 and 3 (8%) in group 2 (P = 0.13). : Invasive breast neoplasia diagnosed by NLBB requires reexcision regardless of tumor margins to achieve complete local surgical eradication of tumor.  相似文献   
4.
Expression of CDX2 and MUC2 in Barrett's mucosa   总被引:3,自引:0,他引:3  
Barrett's mucosa is a risk factor for esophageal adenocarcinoma and should be detected at an early stage. It is defined by the presence of columnar epithelium with goblet cells in the lower esophagus, but histologic diagnosis can be uncertain in the absence of distinct goblet cells. We investigated 55 biopsies from 48 patients with endoscopically plain Barrett's esophagus and performed immunohistochemistry for CDX2 and MUC2. In addition, alcian blue (pH 2,5)/PAS staining was done. In histologically unequivocal Barrett's mucosa, nuclear expression of CDX2 in goblet cells and many columnar cells, as well as cytoplasmic positivity for MUC2 in goblet cells, could be observed. Alcian blue (pH 2,5)/PAS stained acidic mucins in goblet cells and in some non-goblet columnar cells. In six cases, no definite Barrett's mucosa was present, and no expression of MUC2 could be observed. In these biopsies, there was granular cytoplasmic and/or focal nuclear staining for CDX2 in non-goblet columnar epithelial cells, indicating their intestinal differentiation. We suggest that this peculiar mucosa is the precursor of unequivocal Barrett's mucosa and would designate it early Barrett's mucosa. Alcian blue for acidic mucins is inconsistent in this epithelium and does not reliably indicate early intestinal differentiation.  相似文献   
5.
ZK 91296, a partial agonist at benzodiazepine receptors   总被引:2,自引:0,他引:2  
ZK 91296 (ethyl 5-benzyloxy-4-methoxymethyl--carboline-3-carboxylate) is a potent and selective ligand for benzodiazepine (BZ) receptors. Biochemical investigations indicate that ZK 91296 may be a partial agonist at BZ receptors. Such partial agonism may explain to some extent why ZK 91296 needs higher BZ receptor occupancy than diazepam for the same effect against chemical convulsants and for behavioural effects. The lack of sedatiye effects, and the very potent inhibition of reflex epilepsy, spontaneous epilepsy and DMCM-induced seizures suggest, furthermore, that ZK 91296 may possess pharmacological selectivity for a particular type of BZ receptor interaction, perhaps including topographic as well as receptor subtype differentiation.  相似文献   
6.
p53 is the most frequently altered suppressor gene in human cancers. The genotypic and corresponding phenotypic abnormalities of this gene in head and neck squamous cell carcinoma (HNSCC) remain undefined. We analyzed the loss of heterozygosity (LOH) by restriction fragment length polymorphism (RFLP) at three polymorphic loci in the p53 gene and performed immunohistochemistry (MC) for its protein on paraffin-embedded tumor tissue from 20 previously sequenced tumor specimens. LOH was noted at one or more of the three polymorphic sites within the p53 gene in 12 (67%) of the 18 informative samples. Concordance between LOH and mutations was observed in 14 (78%) cases. Twelve (60%) tumors with point mutations were immunohistochemically reactive to p53 antibody and two (10%) lacked both genetic and immunohistochemical alterations. In six tumors (30%) contradictory results between immunohistochemistry and molecular analysis were observed. Our data indicate that: (i) simultaneous deletion and mutation of both p53 alleles was observed in the majority of head and neck squamous carcinomas and implicate this gene in the oncogenesis of these neoplasms, (ii) p53 immunohistochemical analysis may not fully account for the different molecular alterations of this gene, and (iii) no correlation between p53 abnormalities and clinicopathologic or DNA content characteristics of HNSCC was found.  相似文献   
7.
Single-channel measurements were performed with the aim of constructing a detailed molecular scheme for the reaction between -aminobutyric acid (GABA) and a chloride channel of crayfish deep extensor abdominal muscle (DEAM). GABA was applied in pulses to outside-out patches of muscle membrane, and, based on the dose-response of the peak currents and of their rise times, a linear model with five binding steps has been proposed. Evaluation of the single-channel kinetics indicated at least three open states. Two of them originate most probably from the fully liganded receptor state and are grouped in mixed bursts due to their different life times. The third one appears independently, outside the bursts, and originates from a lower liganded receptor state. Simulations of the dose-responses and the open time distributions with this model led to a set of rate constants which generated relatively optimal fits.  相似文献   
8.
Helmuth LL  Mayr U  Daum I 《Neuropsychologia》2000,38(11):1443-1451
The serial reaction time (SRT) task has been frequently used to assess procedural learning of sequences. Patients with Parkinson's disease (PD) have been reported to show deficits on this task, but it is as yet unclear whether this impairment reflects a general sequencing deficit or a deficit in the sequencing of motor-output responses. In order to examine this issue, PD patients and controls were administered an SRT task which allowed the simultaneous and independent assessment of the procedural learning of spatial regularities and the learning of motor-response regularities. PD patients were unimpaired at learning a sequence of spatial locations, but showed a deficit at learning a stimulus-to-motor-response sequence. The results suggest that sequencing impairments in PD are not general, but specific to the type of sequential information inherent in a task.  相似文献   
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