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101.
The article examines the question whether and – if – under which conditions physicians should perform purely esthetic interventions. Starting point of the considerations is the special character of the medical profession and the necessity of the anticipated confidence in the system of medicine. The medical measures for aesthetic improvement are systematized. Medical measures to increase the wanted, positively felt attention of others are not compellingly required according to the medical ethic. Nevertheless they do not offend the ethos if high quality standards are insured: The measures must be presumably helpful for the patient; a thorough informed consent and avoidance of damage must be insured. Esthetic measures, in particular operations which are totally cosmetic, should be limited strictly if performed with children and adolescents. Nevertheless convincing arguments support medical-esthetic measures with children and adolescents to avoid stigmatization.  相似文献   
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A mutant form of ammodytoxin A, a neurotoxic phospholipase A2 from the venom of the long nosed viper Vipera ammodytes ammodytes, was prepared by site-directed mutagenesis, conjugated to a nanogold particle and inoculated into the antero-lateral aspect of one hind limb of female mice. Eight hours later the mice were killed, the soleus muscles of both ipsi- and contra-lateral hind limbs were removed, exposed to a silver enhancing medium and then prepared for transmission electron microscopy. Silver-enhanced particles were subsequently found concentrated in the peri-synaptic area, particularly within the synaptic gutter and the deep synaptic folds, and in many cases had been taken up into the cytoplasm of the terminal boutons of the motor axon. The results suggest that the presynaptic neurotoxicity of snake venom phospholipases A2 involves several components of the neuromuscular apparatus, including intracellular organelles of the motor nerve terminal.  相似文献   
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Background Diagnosis of brainstem lesions in children based on magnetic resonance imaging alone is a challenging problem. Magnetic resonance spectroscopy (MRS) is a noninvasive technique for spatial characterization of biochemical markers in tissues and gives information regarding cell membrane proliferation, neuronal damage, and energy metabolism. Methods We measured the concentrations of biochemical markers in five children with brainstem lesions and evaluated their potential diagnostic significance. Images and spectra were acquired on a 1.5-T imager. The concentrations of N-acetylaspartate, tetramethylamines (e.g., choline), creatine, phosphocreatine, lactate, and lipids were measured within lesions located at the brainstem using Point-resolved spectroscopy sequences. Results Diagnosis based on localized proton spectroscopy included brainstem glioma, brainstem encephalitis, demyelination, dysmyelination secondary to neurofibromatosis type 1 (NF 1), and possible infection or radiation necrosis. In all but one patient, diagnosis was confirmed by biopsy or by clinical follow-up. Conclusions This small sample of patients suggests that MRS is important in the differential diagnosis between proliferative and nonproliferative lesions in patients without neurofibromatosis. Unfortunately, in cases of NF 1, MRS can have a rather misdiagnosis role.  相似文献   
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Precise knowledge of the undesirable effects of chloroquine and hydroxychloroquine allows better exploitation of their therapeutic effects. Retinopathy can be avoided by observing a maximum daily dosage of 3.5-4 mg/kg ideal body weight for chloroquine and 6-6.5 mg/kg for hydroxychloroquine. In this way, both can be used for long-term therapy. The pharmacokinetics of chloroquine (storage in deep compartments with long plasma half-life) means that it can cumulate, especially with higher dosages and in the presence of renal or hepatic insufficiency. A high plasma concentration reinforces the side-effects without reinforcing the therapeutic effects. Besides subjective symptoms (e.g. anorexia, diarrhoea, nausea), the following undesirable reactions are significant. On the skin exanthema, hyperpigmentation and photodynamic reactions can develop. The hair can become white in blonde and red-haired men. In the eye, chloroquine deposits in the cornea and disturbances of accommodation can occur, besides retinopathy. Neuromyopathy and central nervous system disturbances (e.g. psychosis) are rare, as is impairment of auditory function or blood cells. During pregnancy there is a risk of potential fetal damage (hearing loss, abortion). An acute overdose is extremely dangerous: the lethal dose is 1 g for children and 4 g for adults. As death occurs rapidly, chloroquine has to be stored where it is absolutely inaccessible to children.  相似文献   
108.
For various amine transmitters (noradrenaline, dopamine, 5-HT) re-uptake into the releasing varicosity limits the transmitter's life span in the biophase. In the second TiPS Lecture, given at this year's FASEB meeting in Atlanta, Georgia, Ullrich Trendelenburg summarized the evidence relating to the function of the neuronal noradrenaline carrier (uptake1), why it is absolutely dependent on Na+ and Cl- and how it functions as a metabolizing system, hand in hand with intraneuronal monoamine oxidase and vesicular storage. This carrier clears noradrenaline from the extracellular space very efficiently. Hence, loading of incubated organs with exogenous substrates of uptake1 results in a very heterogeneous distribution of the amine. Moreover, under certain experimental and pathophysiological conditions the carrier is able to transport axoplasmic noradrenaline out of the varicosity, a 'release' mechanism operating, for instance, in cardiac ischaemia.  相似文献   
109.
The present study revealed that the majority of nurses had adequate knowledge about dietary practices during the antenatal and post-natal period. However, their knowledge about nutritive value of foods and nutrition advice during disease conditions was inadequate. It is recommended that to make the training more meaningful, the identification of the incorrect dietary beliefs of trainees should be done at the beginning of the training course. Each incorrect belief should be explained in detail for better comprehension of the correct knowledge in nutrition.  相似文献   
110.
A microfluorometric method was used to determine the nuclear DNA content in the nasopharyngeal carcinomas (NPC) of 25 patients treated before 1983. Eleven patients are still alive with no evidence of disease (NED), while the rest died of their disease (DOD). All of the patients received a cycle of radiotherapy, while some also received chemotherapy or neck dissections. The neoplastic cells studied were taken from the original biopsy blocks, deparaffinized, isolated by enzymatic treatment and mechanical fragmentation, and then Feulgen-stained. The cytofluorometric measurement was carried out by a microphotometer equipped for fluorescence excitation and connected to a computer. This method allowed us to construct a histogram of the DNA content in the neoplastic cells. Different neoplastic classes were identified and represent the heteroclonality of the tumor, which can be expressed by the heteroclonality index (HCT). From the collected data it appears that the NED patients all had a low HTC (less than 1) and only 7 of the DOD patients had low HTCs (less than 1). Six of the DOD patients with a low HTC were in advanced stages of their tumor at the time of diagnosis, while the remaining patient did not complete his treatment. Our results show that the DNA analysis of the NPC cell population may offer a useful tool in predicting the biological behavior of this tumor and also improving its treatment.  相似文献   
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