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991.
The effects of localized gamma-irradiation on the in vivo 31P NMR spectra of RIF-1 tumors grown subcutaneously in C3H/HeN mice have been examined before and during the week after treatment. Increases in the ratio of phosphocreatine (PCr) to inorganic phosphate (Pi) and in tumor pH, and decreases in the ratio of Pi to the beta phosphorus resonance of the nucleotide triphosphates (beta NTP) were observed in irradiated tumors. The time course of changes in the 31P spectrum following treatment was the opposite of the pattern during untreated growth, and the magnitude and duration of the changes increased with increasing radiation dose, decreasing clonogenic cell survival and increasing growth delay. To examine the possibility that nontherapeutic systemic effects of the tumor irradiation were responsible for the changes observed, a number of animals bearing two tumors were examined. One tumor on each mouse was selectively irradiated. Changes in tumor volume, Pi/beta NTP, PCr/Pi, the ratio of phosphomonoesters to beta NTP, and tumor pH were all significantly different in the treated compared to the untreated tumor on each animal, indicating that these changes in 31P NMR spectra were a response to radiation therapy and not a systemic response to radiation toxicity.  相似文献   
992.
E S Li 《中华医学杂志》1989,69(11):607-9, 42
The historical review and the necessity of establishment of the Chinese Classification of Diseases (CCD) and Coding System are described. The content, terms used for unified and standardized nomenclatures, coding system including diagnostic terms of traditional Chinese medicine and other codings are introduced. The utility of the CCD system in medical record face sheet management, national native medical statistics, consultative retrieval from terms and codes of diseases, the development and practical trial of ICD-9 CCD is also discussed. Finally, the position and prospect of CCD system in international informatics communication is emphasized.  相似文献   
993.
白马藏人是一支有待识别的民族。本文以肤纹作聚类分析,结果表明白马藏人与藏族的距离很大,很有可能是一支独立的民族。  相似文献   
994.
目的:观察地震灾害对分娩的影响。方法:对我院2008年5月12日至2008年6月12日在地震期间分娩的216例产妇进行回顾性分析。结果:阴道分娩率较地震前比较明显上升,剖宫产率明显下降。结论:地震灾害致孕妇的心理发生变化,导致阴道分娩率上升剖宫产率明显下降。  相似文献   
995.
996.
Background  The mechanism by which transmyocardial revascularization (TMR) offers clinical benefit is controversial. We hypothesized that TMR ameliorates ischemia by reversing paradoxical catecholamine-induced vasoconstriction. Methods and Results  Chronic ischemic cardiomyopathy was created in 11 dogs by placing ameroid constrictors on the proximal coronary arteries and their major branches. Six weeks later, 35 channels were created percutaneously in the left circumflex artery region, with the left anterior descending artery region serving as control. At rest, wall thickening and myocardial blood flow did not change in the treated region, whereas they deteriorated in the control bed. Contractile and myocardial blood flow reserve increased in the treated region but deteriorated in the control region. There was diminished iodine 123 metaiodobenzylguanidine uptake and a significant reduction in noradrenergic nerves in the treated region compared with the control region, with a corresponding reduction in tissue tyrosine hydroxylase activity. Conclusions  We conclude that the absence of a catecholamine-induced reduction in MBF reserve and contractile reserve in the TMR-treated region with associated evidence of neuronal injury indicates that the relief of exercise-induced ischemia after TMR most likely results from reversal of paradoxical catecholamine-induced vasoconstriction. These findings may have implications in selecting patients who would benefit from TMR. Supported in part by grants from the National Institutes of Health (R01-HL66034 and K-08-HL074290-01). Bethesda. Md. The radio-labeled microspheres were provided by DuPont Pharmaceuticals, North Billerica. Mass, and the ultrasound equipment was supplied by Philips. Andover, Mass. Dr Leong-Poi was the recipient of a Fellowship Training Grant from the Canadian Institute of Health Research and the Heart and Stroke Foundation of Canada.  相似文献   
997.
目的:探讨病态肥胖患者行腹腔镜胃减容术时,3种机械通气参数对患者氧合情况的影响。方法:选择行腹腔镜胃减容术的病态肥胖24例,按手术时间顺序分为3组,每组8例。A组:潮气量12ml/kg,呼吸频率10次/min;B组:潮气量20ml/kg,呼吸频率10次/min;C组:潮气量12ml/kg,呼吸频率20次/min。分别于气腹前(T1)、气腹后(T2)抽取动脉血测量pH、PO2、PCO2、Plat(平台压)、Peak(峰压)、AaDO2(肺泡-动脉氧分压差)。结果:气腹后B组Plat(33.2±1.8)cmH2O、Peak(36.3±1.6)cmH2O显著高于A组Plat(29.5±3.9)cmH2O(q=3.053,P〈0.05)、Peak(33.0±2.9)cmH2O(q:2.823,P〈0.05)和C组Plat(28.0±4,1)cmH2O(q:4.290,P〈0.05)、Peak(31.8±2.8)cmH2O(q:4.704,P〈0.05)。其他观察指标无统计学差异。结论:病态肥胖患者在腹腔镜下施行胃减容术时,加大潮气量20ml/kg或加快呼吸频率20次/min不能改善患者的氧合情况。  相似文献   
998.
Introduction Hypothalamic hamartomas are congenital malformations. Clinically, they can be asymptomatic, but they cause seizures, mental retardation and precocious puberty in many cases. Case report A 20-day-old boy with hypothalamic hamartoma and bilateral anophthalmia was presented. Except those, no other congenital anomaly was detected. Conclusion This is a rare case of hypothalamic hamartoma with bilateral anophthalmia. The mutations at SOX2 has an important role in the developing brain and eyes.  相似文献   
999.
Introduction Suprasellar arachnoid cysts are uncommon developmental anomalies that are most often diagnosed in childhood. Because the natural history and pathogenesis of these remain poorly defined, optimal treatment guidelines are not yet established.Case report We report a case of spontaneous disappearance of a suprasellar arachnoid cyst that persisted after a ventriculoperitoneal shunt performed 10 years earlier. A 5-year-old boy presented with impaired visual acuity and urinary incontinence. Magnetic resonance (MR) imaging showed a large suprasellar cyst with noncommunicating hydrocephalus. A ventriculoperitoneal shunt was put in place to alleviate current aggravation of hydrocephalus symptoms. Because of the persistent size of the cyst and signs of brainstem compression on a repeat computed tomography (CT), we recommended surgical exploration and decompression. However, the boy’s parents declined any further surgical treatment, and the patient was subsequently lost to follow-up for 10 years. When the patient returned to our clinic at the age of 15 years, a repeat MR scan showed a complete disappearance of the cyst. His family denied any significant interval history.Discussion This case represents only the third reported case of spontaneous disappearance of a suprasellar arachnoid cyst. We discuss possible mechanisms and clinical characteristics of the disappearance of the arachnoid cyst with review of the literature.  相似文献   
1000.
Background: Chronic pain conditions may result from peripheral nerve injury, chronic peripheral inflammation, or sensory ganglia inflammation. However, inflammatory processes may also contribute to peripheral nerve injury responses. To isolate the contribution of local inflammation of sensory ganglia to chronic pain states, the authors previously developed a rat model in which long-lasting pain is induced by inflaming sensory ganglia without injuring the neurons. This results in prolonged mechanical pain, local increases in proinflammatory cytokines, increased neuronal hyperexcitability, and abnormal spontaneous activity.

Methods: The authors used whole cell patch clamp in acutely isolated small-diameter neurons to determine how localized inflammation (3-5 days) of L4 and L5 ganglia altered voltage-gated K+ and Na+ currents.

Results: Tetrodotoxin-sensitive Na+ currents increased twofold to threefold in neurons from inflamed ganglia. Tetrodotoxin-resistant Na+ currents increased more than twofold, but only in cells that bound isolectin B4. These increases occurred without shifts in voltage dependence of activation and inactivation. Similar results are seen in models of peripheral inflammation, except for the large magnitudes. Unlike most pain models, localized inflammation increased rather than decreased voltage-gated K+ currents, due to increased amplitudes of the sustained (delayed rectifier) and fast-inactivating transient components. The overall effect in current clamp experiments was an increase in excitability as indicated by decreased rheobase and lower action potential threshold.  相似文献   

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