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681.
OBJECTIVE: To assess the success, complications and cost of endoscopic endoprosthesis placement for palliation of obstructive jaundice caused by malignancy. METHODS: Four hundred and two consecutive patients with obstructive jaundice due to nonresectable malignancy undergoing endoscopic stenting were studied. Commercial or home-made 7F or 10F endoprostheses were placed using minor modifications of the standard technique. The accessories were sterilized and reused. RESULTS: Endoprosthesis placement was successful in 291 patients (72.4%, 95% CI 67.7-76.7)-241 in one attempt, 49 in two attempts, and one in three attempts. Fifty nine patients (14.6%, 95% CI 11.4-18.6) had procedure-related complications, including cholangitis (30), pancreatitis (15), perforation (3) and bleeding (11). The incidence of cholangitis was significantly higher in bifurcation blocks than in other lesions (17.6% vs 4.7%, p = 0.0005). The success rate did not differ between distal and proximal lesions (68.1% vs 72.9%). The procedural cost per patient could be reduced from Rs 14,850 to Rs 6565 by reusing accessories after sterilization, and using home-made stents. CONCLUSIONS: Endoscopic endoprosthesis placement is a safe and effective method for palliation of malignant obstructive jaundice. Preparation of indigenous stents and reuse of accessories can reduce the cost of the procedure by over 50%.  相似文献   
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The rapid manual ParaSight-F test of Plasmodium falciparum malaria, an antigen capture test for detecting trophozoite-derived histidine rich protein-2 (PF HRP-2), is simple to perform and provides a definite diagnosis within 10 minutes. During an operational trial at health centers and mobile malaria units where microscopical diagnosis is not available and using defined symptom screening criteria, 3,361 subjects were tested yielding 618 positives (18.4%) for PF-HRP-2 by ParaSight-F. Microscopic examination of the same subjects by thick blood film examined 7 days later at a malaria clinic showed 578 falciparum, and 349 vivax and mixed infection (F+V) 41. The technology proved highly effective in detecting falciparum malaria at the peripheral levels where access to malaria laboratory services are difficult, thus allowing immediate administration of a complete course of treatment in the absence of a microscopic examination.  相似文献   
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Pseudoxanthoma elasticum (PXE) is a classic inherited disorder of the elastic tissue characterized by progressive calcification of elastic fibers with a pathognomonic histological appearance. The clinical manifestations of PXE typically involve the skin, the eye and the cardiovascular system, resulting in skin lesions, decreased vision and vascular disease. Clinically, a more common autosomal recessive and a less common autosomal dominant pattern of inheritance, with high penetrance, have been described; the estimated prevalence of the disease is 1 in 70,000-100,000. Previous failure to link the disease to any of several candidate genes prompted us to conduct a genome-wide screen on a collection of 38 families with two or more affected siblings, using allele sharing algorithms. Excess allele sharing was found on the short arm of chromosome 16 and confirmed by conventional linkage analysis, localizing the disease gene under a recessive model with a maximum two point lod score of 21.27 on chromosome 16p13.1, an area so far devoid of any obvious candidate genes. Under a dominant transmission pattern linkage with a maximum two point lod score of 14.53 was observed to the same region. Linkage heterogeneity analysis predicted the presence of allelic heterogeneity with different variants of a single gene that resides in this chromosomal region accounting for recessive and dominant forms of PXE.  相似文献   
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We attempted to elicit automatic stepping in healthy humans using appropriate afferent stimulation. It was found that continuous leg muscle vibration produced rhythmic locomotor-like stepping movements of the suspended leg, persisting up to the end of stimulation and sometimes outlasting it by a few cycles. Air-stepping elicited by vibration did not differ from the intentional stepping under the same conditions, and involved movements in hip and knee joints with reciprocal electromyogram (EMG) bursts in corresponding flexor and extensor muscles. The phase shift between evoked hip and knee movements could be positive or negative, corresponding to 'backward' or 'forward' locomotion. Such an essential feature of natural human locomotion as alternating movements of two legs, was also present in vibratory-evoked leg movements under appropriate conditions. It is suggested that vibration evokes locomotor-like movements because vibratory-induced afferent input sets into active state the central structures responsible for stepping generation.  相似文献   
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Spontaneous neuronal activity plays an important role in the development of cortical circuitry, yet its spatio-temporal dynamics are poorly understood. Cajal-Retzius (CR) neurons in developing layer 1 are necessary for correct cortical lamination and are strategically located to coordinate early circuit activity. To characterize the spontaneous activity of CR and other layer 1 neurons during cortical development, we imaged calcium transients in populations of layer 1 neurons in hemispheres and slices from postnatal rat somato-sensory neocortex. The spontaneous activity in layer 1 had complex spatio-temporal patterns. Groups of non-CR cells showed synchronous activations and formed networks of correlated neurons superimposed in the same territory. Correlated activity among non-CR cells was mediated by a depolarizing effect of GABA and was modulated by glutamate, probably released by CR cells. Our findings demonstrate that developing layer 1 can sustain complex patterns of correlated activity and reveal a circuit mechanism that can mediate this patterned activity.  相似文献   
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Hearing loss is an uncommon symptom in multiple sclerosis. We report two patients in whom unilateral sudden hearing loss was the first monosymptomatic manifestation of multiple sclerosis. We confirmed the initial central auditory dysfunction suggested by audiometric findings and brainstem auditory evoked potentials by MRI, which showed a unilateral pontine lesion in one patient and a lesion in the medulla oblongata in the other.  相似文献   
690.
CFIDS (chronic fatigue and immune disfunction syndrome) is also known as CFS (chronic fatigue syndrome), CEBV (chronic Epstein-Barr virus), M.E. (myalgic encephalomyelitis), yuppie flu and by other names. It is a complex illness characterized by incapacitating fatigue (experienced as exhaustion and extremely poor stamina), neurological problems and a constellation of symptoms that can resemble many disorders, including; mononucleosis, multiple sclerosis, fibromyalgia, AIDS-related complex (ARC) and autoimmune diseases such as lupus. These symptoms tend to wax and wane, but any often severely debilitating and may last for many months or years. All sections of the population (including children) are at risk, but women under 45 seem to be most susceptible. The investigators suggest that CFIDS results from dysfunction of the immune system. The exact nature of this dysfunction is not yet well defined, but it can generally be viewed as an unregulated or overactive state which is responsible for most of the symptoms. There is also evidence of some immune suppression in CFIDS. None of the treatments is consistently satisfactory, but some may be helpful: psychotherapy, physiotherapy, exercise programs, acupunctures, small doses of antidepressants, etc.  相似文献   
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