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61.
Following dark incubation of isolated retinas of Xenopus laevis in Ringer solution supplemented with 3H-2 Deoxy-D-glucose (2DG), virtually all of the uptake of the label was by the inner segments and synaptic bases of the photoreceptor cells. Autoradiographs prepared from conventionally fixed tissue showed the same cellular distribution of label as those prepared from identically incubated, unfixed, freeze-dried retinas. However, fixation removed about 77% of the total counts. This fixation-labile, soluble fraction was identified as being primarily 2DG-6 phosphate by thin-layer chromatography. The remaining insoluble fraction corresponded in distribution to glycogen grains. In cones, glycogen is stored primarily in the paraboloid, whereas in rods it is distributed throughout the inner segment and synaptic base. EM autoradiographs illustrated that these were the sites over which fixationresistant 2DG label was localized. Measurements of radioactivity associated with extracts of retinal glycogen following 2DG incubation demonstrated that a disproportionately high fraction of total counts were associated with the glycogen fraction. We conclude that in the amphibian retina 2DG may be incorporated into glycogen.  相似文献   
62.
User satisfaction with the care of hospitalized children is examined in this paper It is argued that parents are proxy consumers but that their status is conditional on the way in which they exercize choices Parents' involvement in the care of their children means that the term 'user' is more appropriate than 'consumer' Methodological problems in the assessment of user satisfaction are discussed A study of the experiences of parents of 24 children discharged from a surgical ward of a children's hospital is described and the implications for the assessment of user satisfaction reviewed The study demonstrates that qualitative methods have value in the assessment of user satisfaction with care A particular strength of qualitative methods of inquiry is that limitations of users' choice in care can be assessed  相似文献   
63.
Electrophysiological stimulation of the hypothalamic ventromedial nucleus (VMN) resulted in an increase in interscapular brown adipose tissue (BAT) temperature in both lean and obese (fa/fa) rats. Graded stimulations resulted in progressively larger temperature increases in both lean and obese (fa/fa) groups. Both intraperitoneal injection of propranolol and surgical denervation (but not sham denervation) abolished the increase in BAT temperature following VMN stimulation, in both lean and obese (fa/fa) groups. Electrical stimulation of the supraoptic region, and certain anterior hypothalamic regions also resulted in increases in BAT temperature of lean and obese (fa/fa) rats, but stimulation of the dorsomedial nucleus and regions of the lateral hypothalamus did not affect BAT temperature. All hypothalamic regions capable of activating BAT gave a similar maximum rise in temperature for a given stimulus in lean and obese (fa/fa) rats. These results suggest that the efferent sympathetic pathway from the VMN and other hypothalamic regions of BAT is normal in the obese (fa/fa) rat.  相似文献   
64.
The decisions which health care professionals make are the basis of treatment and care given. In order to evaluate effective care it seems logical to suggest that an awareness of the decisions which health care professionals make and how they make them is needed. This study examines the processes nurses use when making decisions about the health care needs of acutely ill patients. In stage one, 104 qualified nurses were interviewed to identify how they decide health care needs. In stage two, a 'think aloud' technique was used with patient simulations to obtain verbal protocols from a further 55 qualified nurses to identify the information strategies they used when making these decisions. The results suggest that nurses base their health care decisions mainly on their assessment of qualitative patient states or conditions. Initial indications are that the processes used differ from those characterized in the diagnostic reasoning model, with the context in which decisions are made being an important influence together with nurses' experience. It is suggested that, in order to develop effective predictive models and clinical guidelines which aid decision making, more research into the nature of health care professionals' decision making is carried out.  相似文献   
65.
In man the clinical patterns of inorganic and organic mercury toxicity are different. Inorganic mercuric chloride mainly affects the renal and gastrointestinal systems. The characteristic neurological feature is a fine tremor, particularly of the hands and fingers. In contrast organic methyl mercury toxicity results in an exclusively neurological disorder, the characteristic features being ataxia, dysarthria, paresthesia and tunnel vision. To study the action of these classes of mercury compounds on neurones small amounts of mercuric chloride or methyl mercuric acetate were injected or iontophoresed into the rat cerebrum. The ultrastructural changes which followed were identical. Progressive and often pronounced cytoplasmic swelling of neurones suggested a defect at the cell membrane level. Thus is spite of their distinctive clinical syndromes these 2 classes of mercury compounds are capable of inducing neuronal necrosis.  相似文献   
66.
Seventeen patients with intracranial meningiomas were studied with positron emission tomography and fluorine-18-2-fluorodeoxyglucose (PET-FDG) to assess the glucose utilization of these tumors. Four meningiomas followed for 3-5 years after PET-FDG and surgery showed no evidence of recurrence. These tumors had significantly lower glucose utilization rates (1.9 mg/dl/min +/- 1.0) than 11 recurrent or regrowing meningiomas (4.5 mg/dl/min +/- 1.96) (P less than .01). The glucose metabolic rates of meningiomas correlated with tumor growth, as estimated from changes in tumor size on repeated computed tomographic scans. Histopathologically, a syncytial (atypical) meningioma had the highest glucose utilization rate, followed by a papillary meningioma and an angioblastic meningioma. Individual transitional and syncytial (typical) meningiomas showed marked differences in glucose metabolism despite similar microscopic appearance. Glucose utilization rate appears to be at least as reliable as histologic classification and other proposed criteria for predicting the behavior and recurrence of intracranial meningiomas.  相似文献   
67.
Intracellular recordings were performed in the CA1 region of the rat hippocampus following an ipsilateral intraventricular injection of kainic acid. Seven days postlesion, graded bursts of up to four action potentials could be evoked by stimulation of the stratum radiatum. The evoked EPSPs underlying these bursts showed a prolonged 10-90% rise time and half-width compared to control EPSPs, an absence of a significant inhibitory phase, and an increase in magnitude and duration at depolarized resting levels. The evoked EPSPs also exhibited a significant decrease in amplitude and time course in response to D-APV (D-2-amino-5-phosphonovaleric acid; 1-20 microM), though this effect was variable from cell to cell. The prolonged time course, voltage sensitivity, and response to a selective NMDA antagonist confirmed that the major component of the EPSP in neurons from lesioned slices was mediated by NMDA receptors. The partial denervation of the CA1 area induced by the kainic acid led to both an enhanced NMDA-mediated excitatory phase and a decrease in postsynaptic inhibition, resulting in the pronounced hyperexcitability noted in the lesioned slices.  相似文献   
68.
True invasive tubular breast carcinoma (TBC) is unlikely to metastasize to axillary nodes, yet it is routinely subjected to sentinel lymph node biopsy (SLNB), even if the diagnosis was suspected preoperatively. The positive predictive value (PPV) of core biopsy for TBC and the incidence and predictors of axillary metastasis in invasive breast carcinomas identified as tubular‐rich on core biopsy are unknown. Prospective patient and tumor data regarding postoperatively confirmed TBCs, and tubular‐rich carcinoma identified on preoperative core biopsy between January 2005 and May 2016 was analyzed retrospectively. Axillary metastasis occurred in only 4.2% (4/95) of TBCs, all of which measured >15 mm pathologically. In 11.1% (11/99) of TBCs, the initial core biopsy was either indeterminate/suspicious or ductal carcinoma in situ (DCIS); therefore, their true tubular histotype and size were ascertained following operative excision and before SLNB. Nine were ≤15 mm, and all were node‐negative. Only 63.9% (46/72) of tubular‐rich core biopsies were confirmed as TBCs; the remaining 36.1% (26/72) were well‐differentiated invasive nontubular carcinomas. None of the preoperative patient or tumor features were predictive of true TBC on multivariable analysis; 10.1% (7/69) of carcinomas identified as tubular‐rich on core biopsy (regardless of their true histotypes) were node‐positive; 23.1% (6/26) in nontubular and 2.3% (1/43) in true tubular carcinomas. Preoperative ultrasound size >15 mm was associated with axillary metastasis in 40.0% (4/10) compared to 5.7% (3/53) in those ≤15 mm (OR = 11.11, 95% CI = 1.99‐62.04; multivariable P = .010). Axillary metastasis in TBC is dependent on pathological size; therefore, a case is made for omitting SLNB in small true TBCs confirmed following excision. Preoperative tubular‐rich core biopsy is not adequately diagnostic of TBC; however, it selects carcinomas that are well‐differentiated, small, and unlikely to metastasize to the axilla, thus allowing for the selective omission of SLNB.  相似文献   
69.
目的 总结5例肺动脉血栓内膜剥脱术治疗慢性肺动脉血栓栓寨症术后神经系统障碍的患者的临床表现特点,并尝试分析其原因.方法 回顾2002年至2010年,26例因慢性血栓栓塞性肺动脉高压症行肺动脉血栓内膜剥脱术的患者围手术期资料.总结术后生存患者中5例出现神经功能障碍并发症者的临床与影像学特点,分析其与无并发症患者的手术前、手术中的资料,寻找可能的影响因素.结果 26例中围手术期死亡4例,22例生存者心功能改善,生活质量明显提高.5例围手术期出现神经系统障碍表现者中,3例表现为嗜睡、谵妄、记忆力障碍,颅脑CT未见异常发现,治疗后症状1周内消失,2周内完全恢复;另2例患者除上述症状外,还表现为共济失调、步态不稳、舞蹈样动作,症状持续时间长,其中1例经高压氧治疗后1个月症状好转,颅脑CT未见异常发现,颅脑MRI显示双侧中脑,基底节区异常信号,治疗8周症状基本好转出院,6个月症状完全消失,复查颅脑MRI异常信号消失;1例颅脑CT未见异常发现,12周出院,恢复较差,生活部分自理.术后出现神经系统障碍患者Jamieson手术分型Ⅲ型、Ⅳ型比例较多(P=0.024),手术中停循环时间较长(P=0.034).结论 肺动脉血栓内膜剥脱术后早期神经系统障碍多表现为弥漫性脑皮层与对称性基底节区神经功能障碍,颅脑MRI相应区域异常信号,多数患者症状在2-8周内消失,6个月内颅腩MRI异常信号可以消失.出现神经系统功能障碍的患者多手术操作难度大,停循环时间较长,推测考虑与术中脑缺血缺氧有关.
Abstract:
Objective Investigate the clinical features of the neurological disorders in patients after pulmonary thromboendarterectomy (PTE) for chronic pulmonary thromboembolism , analyze the factorial. Methods A retrospective study was made of 26 patients who underwent PTE between 2002 and 2010 in Beijing Chao-Yang hospital. The symptom of neurological system disorders occurred in the survivors were been investigate. The preoperative conditions and the perioperative conditions of all survivors were investigated. Compared the differences between the groups with neurological system disorders and the groups without. Results There were 22 patients of 26 survived after the surgery. Cardiac function of the survivors improved, and the quality of life improved significantly. 5 cases of the 22 survivors had symptoms of neurological system disorders. 3 patients showed lethargy, delirium, memory disorders, brain CT found no abnormal, symptoms recovered within 2 weeks. The fourth patient showed ataxia, unsteady gait, dance-like movements symmetry, in addition to the above symptoms, brain CT no abnormal showed,brain MRI showed bilateral abnormal signal in the midbrain, basal ganglia, symptoms improved and discharged after 8 weeks, the symptoms completely disappeared 6 months, and the abnormal signals in brain in MRI disappeared. The fifth patient with similar symptoms to the fourth, brain CT no abnormal found, be discharged 10 weeks after the operation, recovery is poor, living part of themselves. The postoperative neurological disorders occurred in the patients of Jamieson surgery type Ⅲ type, Ⅳ type of larger proportion, (P = 0.024), longer circulatory arrest surgery (P = 0.034). Conclusion The neurological disorders postoperative PTE often showed diffuse symmetric cerebral cortex and basal ganglia nerve dysfunction, brain MRI showed abnormal signal corresponding region, the majority of symptoms disappeared in 2 - 8 weeks, abnormal signal in brain MRI could disappeared after 6 months. Neurological dysfunction occurs in patients with more difficult surgical procedure, longer circulatory arrest, suggesting that with the surgery cerebral ischemia and hypoxia related.  相似文献   
70.
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