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Fifty-nine patients with head and neck carcinoma were examined with 67Ga scintigraphy. All patients had undergone lymph node dissection of the neck. They were followed for a minimum of 2 years after the examination. The primary tumor, treated prior/contemporaneously to the lymph node dissection, did not evolve in this interval. Metastatic involvement of the lymph node capsule was observed in all 44 cases with metastatic lymph nodes; macroscopic radicality was surgically obtained since involvement of the capsule was only microscopic. Nevertheless, complementary radiotherapy was given. The whole of 17 recurrences in the soft tissues of the neck were found, within 2 years, in the group of 26 patients who had undergone dissection of lymph nodes with metastatic capsular involvement and whose postoperative 67Ga scintigraphy was positive. On the contrary, no recurrences in the soft tissues of the neck were observed in the group of 18 patients who had undergone dissection of lymph nodes with metastatic capsular involvement and whose scintigraphy was negative. This result proves (P less than 0.001) 67Ga capable of evidencing eventual microscopic diffusion. Such a possibility has not yet been realized in vivo with any other investigation technique. Scintigraphy was negative in a control group of 15 patients who had undergone lymph node dissection, and with nonmetastatic lymph nodes. This finding leads us to exclude that the use of 67Ga might result in misinterpreted findings in the exploration of relatively superficial tissues. In fact, the eventual accumulation of radioisotope in nonneoplastic pathologies is quite easily recognizable in the neck. We can therefore conclude that in those 9 cases with positive scintigraphy and in whom no recurrence was found, microscopic diffusion was probably present, but local recurrence of the disease was prevented by complementary radiotherapy.  相似文献   
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BACKGROUND: Optical penalization (OP) has previously been shown to successfully maintain vision in amblyopic eyes of older children when patching compliance is poor and when vision decreases once patching is discontinued. This study shows that the final vision in optically penalized eyes is often better than the vision obtained after patching alone. SUBJECTS AND METHODS: During the 5-year period from January 1992 to February 1997, 28 children aged between 3.7 and 8.2 years (average age, 6.5+/-1.1 years) were optically penalized for an average of 1.5+/-0.75 years. The maximum length of penalization was 3.3 years, whereas the minimum time was 6 months. There were 21 children with strabismic amblyopia and 7 children with anisometropic amblyopia. All 28 children had worn a patch to achieve their best visual levels and then had shown a loss of best vision when occlusion was stopped. Patching was usually resumed and continued until the previous best vision was obtained; at this point OP was started to "maintain" vision. Eighteen of the 28 children have discontinued penalization and have been followed up an average of 1(1/2) years. RESULTS: Twenty-six (93%) of the 28 patients showed an increase in best vision from that found at the conclusion of patching, and 2 patients maintained their vision at the initial level. The average visual acuity at the start of penalization was 20/50 (0.42+/-0.11 logarithm of the minimum angle of resolution [log MAR]). Final average visual acuity was 20/27 (0.15+/-0.12 log MAR). The average increase in vision was nearly 3 lines or 0.27+/-0.12 log MAR. CONCLUSION: OP alone (without the use of pharmacologic agents such as atropine) not only maintains vision after patching therapy, but also appears to improve the final visual outcome.  相似文献   
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目的:筛选一株优良的抗生素产生菌。方法:通过人为诱变来动摇产生菌原有的严密控制机制。结果:得到一种抗生素生物合成能力异常的突变株。结论:此方法可过量合成人们所期望的抗生素。  相似文献   
5.
目的:考察盐酸特拉唑嗪胶囊的稳定性。方法:通过影响因素(强光照射、高温、高温),加速和留样考察实验,以含量为测定指标,考察胶囊的含量变化。结果:在温度40℃、60℃、光照3500LX及RH75%等因素影响下,胶囊的含量无明显变化。结论:在25℃时,通过经典恒温加速试验推测盐酸特拉唑嗪胶囊的失效期为2年。  相似文献   
6.
NAMI-A is a ruthenium complex endowed with a selective effect on lung metastases of solid metastasizing tumors. The aim of this study is to provide evidence that NAMI-A's effect is based on the selective sensitivity of the metastasis cell, as compared with other tumor cells, and to show that lungs represent a privileged site for the antimetastatic effects. The transplantation of Lewis lung carcinoma cells, harvested from the primary tumor of mice treated with 35 mg/kg/day NAMI-A for six consecutive days, a dose active on metastases, shows no change in primary tumor take and growth but a significant reduction in formation of spontaneous lung metastases. Transmission electron microscopy examination of lungs and kidney shows NAMI-A to selectively bind collagen of the lung extracellular matrix and also type IV collagen of the basement membrane of kidney glomeruli. The half lifetime of NAMI-A elimination from the lungs is longer than for liver, kidney, and primary tumor. NAMI-A bound to collagen is active on tumor cells as shown in vitro by an invasion test, using a modified Boyden chamber and Matrigel, and it inhibits the matrix metallo-proteinases MMP-2 and MMP-9 at micromolar concentrations, as shown in vitro by a zimography test. These data show NAMI-A to significantly affect tumor cells with metastatic ability. Binding to collagen allows NAMI-A to exert its selective activity on metastatic cells during dissemination and particularly in the lungs. These data also stress the wide spectrum of daily doses and treatment schedules at which NAMI-A is active against metastases.  相似文献   
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Schwann cells are glial cells of peripheral nervous system, responsible for axonal myelination and ensheathing, as well as tissue repair following a peripheral nervous system injury. They are one of several cell types that are widely studied and most commonly used for cell transplantation to treat spinal cord injury, due to their intrinsic characteristics including the ability to secrete a variety of neurotrophic factors. This mini review summarizes the recent findings of endogenous Schwann cells after spinal cord injury and discusses their role in tissue repair and axonal regeneration. After spinal cord injury, numerous endogenous Schwann cells migrate into the lesion site from the nerve roots, involving in the construction of newly formed repaired tissue and axonal myelination. These invading Schwann cells also can move a long distance away from the injury site both rostrally and caudally. In addition, Schwann cells can be induced to migrate by minimal insults (such as scar ablation) within the spinal cord and integrate with astrocytes under certain circumstances. More importantly, the host Schwann cells can be induced to migrate into spinal cord by transplantation of different cell types, such as exogenous Schwann cells, olfactory ensheathing cells, and bone marrow-derived stromal stem cells. Migration of endogenous Schwann cells following spinal cord injury is a common natural phenomenon found both in animal and human, and the myelination by Schwann cells has been examined effective in signal conduction electrophysiologically. Therefore, if the inherent properties of endogenous Schwann cells could be developed and utilized, it would offer a new avenue for the restoration of injured spinal cord.  相似文献   
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Background

Cancer is one of the most common causes of death among morbidly obese individuals. Obese individuals have a well-documented increased risk of colon cancer. No guidelines are available for the workup of bariatric surgery patients in relation to colon cancer.

Methods

The indications for screening colonoscopy at the Bariatric and Metabolic Institute Abu Dhabi (BMI Abu Dhabi) include all patients older than 50 years [40 years if patients are United Arab Emirates (UAE) nationals] with unexplained abdominal symptoms, anemia of unknown cause, or a family or personal history of colonic pathology. This study retrospectively reviewed the charts of all the patients who had colonoscopy during the period January 2009 to January 2013. The patients were divided into two groups: group A [patients with a body mass index (BMI) > 30 kg/m2] and group B (patients with a BMI < 30 kg/m2). The demographics and the prevalence of polyps and cancer in the two groups were compared.

Results

During the study period, 341 colonoscopies were performed: 137 for patients with a BMI higher than 30 kg/m2 (mean age, 44 years) and 204 for patients with a BMI lower than 30 kg/m2 (mean age, 46 years) (P > 0.05). The overall prevalence of adenomatous polyps was 6.74 % and that of cancer was 1.75 %. Further analysis showed that the prevalences of adenomatous polyps and cancer were respectively 12.4 and 2.1 % for the patients with a BMI higher than 30 kg/m2, whereas the prevalences were respectively 2.9 and 0.9 % for the patients with BMI lower than 30 kg/m2 (P < 0.001).

Conclusion

The risk for the development of colonic adenomatous polyps and cancer is high among young obese individuals in the Middle East. Guidelines are needed to establish criteria for screening in this group of individuals.  相似文献   
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