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991.
BACKGROUND: This study was performed to identify pathologic and clinical features that best predict disease free survival of patients with early stage small cell carcinoma of the cervix treated by radical hysterectomy. METHODS: Three hundreds and seventy patients with cervical carcinoma were analyzed retrospectively to define those variable that best predict disease free survival (DFS). Variables included age, weight, race, marital status, economic status, tumor size, depth of invasion (DI), lymph-vascular space involvement (LVSI), cell type, tumor grade, lymph node metastasis (LNM), and total number of lymph nodes removed. Patients with lymph node metastasis, parametrial involvement, and positive or close surgical margins were offered postoperative radiation. RESULTS: Twelve patients were found to have small cell carcinoma (3.2%). One patient had microinvasive carcinoma of the cervix (MIC) as defined by the Society of Gynecologic Oncologists with a depth of invasion of 3 mm or less and no lymph-vascular space invasion, and has been reported previously. A detailed analysis of the other patients with nonsmall cell carcinoma is presented separately. Five patients achieved a DFS of at least 5 years, whereas 7 patients died with disease. Excluding the patient with MIC, the 5-year DFS rate was 36.4%. CONCLUSIONS: Relative to other cell types, small cell carcinomas of the cervix is an aggressive neoplasm with a higher rate of LVSI and LNM despite smaller DI and tumor size. These data suggest that multimodality therapy, combining radical surgery and radiation with cytotoxic chemotherapy, may provide these patients with the best chance for cure.  相似文献   
992.
Electromyographic analysis of gait in eight patients who had had a modified Van Nes rotationplasty was performed to compare the activity of the flexors and extensors of the ankle on the side of the operation with that of the flexors and extensors of the knee on the normal, contralateral side. The resemblance in the activity of the extensors was more pronounced than that of the flexors. In three patients, the angle of flexion of the knee throughout the gait cycle was the same on the side of the rotationplasty as on the normal side. There was more symmetry in the swing phase than has been reported for patients who have had an above-the-knee amputation. The strength of the dorsiflexors of the ankle on the side of the rotationplasty was 68 percent and that of the flexors was 71 per cent when compared with that of the muscles of the normal ankle.  相似文献   
993.
994.
995.
The survey records the data supplied by the 290 respondents to a questionnaire sent out to the first 390 male graduates of the Royal Free Hospital School of Medicine who qualified during the 20 year period after the school became co-educational in 1948. As might have been expected, there was a preponderance of students from homes in Greater London and South East England. Whilst an equal entry of male and female students was felt desirable the achievement of this objective was slow, since selection was based on merit and the male applicants in the first few years seemed less well qualified for the medical training. During the period of the survey half of the entry was at the premedical stage and the average age for starting preclinical studies was 20-0 years--a little higher than that (18-9) recorded in the ASME survey for the 1966 entry to medical schools. A slightly higher number of Royal Free men took higher degrees and diplomas than did the women. On the number available it appeared that a higher percentage of Royal Free men took MRCP as compared with women or Birmingham graduates. The DA and DCH qualifications were more favoured by women than men. Three times as many men worked in, and twice as many lived in London as in South East England, a situation that was the reverse of that for Royal Free women. There was no evidence to show that the men preferred to do career training in London and then move out.  相似文献   
996.
The functional state of the amacrine cells which contain enkephalin-, neurotensin- and somatostatin-like immunoreactivity of the chicken retina was monitored by measuring the rate of change in the levels of [Leu]enkephalin-like immunoreactivity in the retina. Dark-adapted birds were exposed to lights of different intensities for 12 h. At light levels of < or = 0.03 microW/cm2, the ENSLI amacrine cells were highly active but, by 0.08 microW/cm2, they reached a state of maximum inactivation. Thus, the ENSLI amacrine cells act as flip-flop devices, inactivated by critical levels of light, which correspond to those which inactivate pineal melatonin synthesis. They may, therefore, be involved in retinal pathways which signal the difference between day and night.  相似文献   
997.
铝双层板结构超高速正撞击后板弹坑分布   总被引:1,自引:0,他引:1  
利用二级轻气炮发射2017-T4铝合金球形弹丸,对铝合金双层板结构进行超高速正撞击试验研究,从而模拟空间碎片对航天器防护结构的撞击作用.弹丸直径为2.00~6.35 mm,弹丸撞击速度为1.50~6.98 km/s,撞击角度为0°,试验得到不同撞击速度区间内的铝合金双层板结构后板弹坑分布模式.分析铝合金双层板结构后板弹坑分布特性,建立预测铝合金球形弹丸超高速正撞击铝合金双层板结构后板弹坑分布的经验公式.结果表明,在正撞击条件下,铝合金双层板结构的后板弹坑呈圆形区域分布,后板弹坑分布区域随弹丸直径、撞击速度和前后板间距的增加而增大,弹丸的撞击破碎临界速度将影响后板的弹坑分布模式.  相似文献   
998.
Kimura's disease     
An Asian man aged 42 had a pre-auricular swelling on the left with local skin itching. Owing to the highly probably benign nature at examination, surgical treatment was refrained from. One year later, the swelling had increased while the itching was unchanged, so that surgical excision was performed. Morbid-anatomical examination revealed angiolymphoid hyperplasia with eosinophilia, compatible with Kimura's disease. Kimura's disease is a chronic inflammatory disorder which is very rare in Europe, but which is frequently diagnosed in Asian countries and in immigrants from these countries. Tumours in the head and neck region, enlarged lymph nodes and increased eosinophil counts are typical signs. The IgE level is increased. The cause of this disease is so far not clear, although there are indications that an inflammatory reaction to an unknown allergen plays a part. It is essential that this disease should be distinguished in the diagnostic work-up from presence of a malignancy. Fine-needle aspiration cytology is often inconclusive; as a rule the diagnosis can only be made after surgical excision of the tumour. There is no consensus on the treatment of this disease, but symptomatic therapy usually suffices.  相似文献   
999.
BACKGROUND: This investigation examines the question of whether decreasing wavelength of light and/or reducing luminance benefits oculomotor efficiency in normal and reading disabled (RD) children. METHODS: Two groups of children were identified as normal or disabled readers using standardized reading tests. After suitable practice, eye movements were objectively measured with the Visagraph II as each of the subjects silently read a series of three different selections at their independent reading level with clear (control), gray, and blue filters. Four variables were measured for each subject. Data were analyzed using a repeated measure ANOVA and post hoc tests. RESULTS: The standardized reading tests significantly differentiated average from poor readers using grade scores and percentiles. Initially, with clear filters, eye movement scores of normal readers were superior to disabled readers for fixations regressions, and rate of reading. Among the RDs--but not the normals--the three variables improved with the blue filter when compared with the clear filter, number of fixations and regressions were significantly lower, and rate was significantly higher. Gray filters yielded no significant changes. Improvement with the blue filters normalized the three variables in that there were no significant differences between normal and disabled readers. CONCLUSION: This investigation confirms a link between wavelength of light and eye movement efficiency in reading. Blue filters resulted in a significant improvement in the number of fixations and regressions and rate of reading in RD children. The outcome broadens the concept of transient system deficit established in previous research to include the effect on oculomotor efficiency. The educational implications of this study are of special interest to optometrists.  相似文献   
1000.
The marine guanidinium toxins, saxitoxin (STX) and tetrodotoxin (TTX), have played crucial roles in the study of voltage-gated Na+ channels. Because they have similar actions, sizes, and functional groups, they have been thought to associate with the channel in the same manner, and early mutational studies supported this idea. Recent experiments by. Biophys. J. 67:2305-2315) have suggested that the toxins bind differently to the isoform-specific domain I Phe/Tyr/Cys location. In the adult skeletal muscle Na+ channel isoform (microliter), we compared the effects on both TTX and STX affinities of mutations in eight positions known to influence toxin binding. The results permitted the assignment of energies contributed by each amino acid to the binding reaction. For neutralizing mutations of Asp400, Glu755, and Lys1237, all thought to be part of the selectivity filter of the channel, the loss of binding energy was identical for the two toxins. However, the loss of binding energy was quite different for vestibule residues considered to be more superficial. Specifically, STX affinity was reduced much more by neutralizations of Glu758 and Asp1532. On the other hand, mutation of Tyr401 to Cys reduced TTX binding energy twice as much as it reduced STX binding energy. Kinetic analysis suggested that all outer vestibule residues tested interacted with both toxins early in the binding reaction (consistent with larger changes in the binding than unbinding rates) before the transition state and formation of the final bound complex. We propose a revised model of TTX and STX binding in the Na+ channel outer vestibule in which the toxins have similar interactions at the selectivity filter, TTX has a stronger interaction with Tyr401, and STX interacts more strongly with the more extracellular residues.  相似文献   
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