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91.
Vibrio cholerae O139: How great is the threat of a pandemic?   总被引:3,自引:0,他引:3  
The emergence of the new strain Vibrio cholerae O139 and its rapid spread in Bangladesh and India together with its detection in several other countries, have raised the question whether this constitutes the beginning of the eighth pandemic of cholera, and if so, how large a threat it poses. In an attempt to answer this question, epidemic spread patterns of Vibrio cholerae O139 strain in Bangladesh were studied. Initially the epidemic moved quickly and affected the entire coastal and estuarine tidal plains of southern Bangladesh. In the flood plains of the northern regions it affected mostly the north‐eastern and north‐central areas, at a slower pace than in the southern areas. In the beginning the new strain totally displaced both biotypes (classic and El Tor ) of Vibrio cholerae O1. Nearly 2 years after its initial detection, striking differences in the distribution of V. cholerae O139 and O1 were observed. In most northern areas, the new strain was replaced by V. cholerae O1, whereas in the southern coastal regions, the O139 strain continues to dominate epidemics. The study suggests that the O139 strain may become endemic in the coastal ecosystem. The threat of a pandemic, therefore, may not be as large as it first seemed.  相似文献   
92.
We report the clinical and laboratory findings in the largest kindred so far recorded with familial amyotrophic lateral sclerosis due to an A4T mutation in the SOD1 gene. The age of onset ranged from 32 to 60 years, with a mean of 46 years. Weakness in the legs was the most frequent early symptom and there was a predominance of lower motor neuron signs. The mean time from onset of symptoms to death was 14 months. One man with onset at the age of 37 has shown a slowly developing form and is currently alive 76 months after diagnosis (October 2002), although severely affected. The A4T mutation, with one exception, was of similar severity to the A4V mutation.  相似文献   
93.
We describe the development of severe lipoatrophy in a patient treated with biphasic aspart. This complication of insulin therapy was common in the past with the use of animal insulins and became less common with the increasing purification of these and the introduction of recombinant human insulin. This patient developed severe lipoatrophy with the use of a premixed insulin containing the analogue insulin aspart. Lipoatrophy although rare can still occur even with the use of technologically advanced insulin preparations.  相似文献   
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95.
The present study was conducted to see the diagnostic efficacy of serum anti-TB IgG antibody detection in adult pulmonary tuberculosis (TB) by ELISA and Immunochromatography test (ICT) method using commercially available diagnostic kit (Pathozyme TB complex and MycoDot test respectively). This case-control study included 48 cases of adult pulmonary TB within the age range of 15-65 years. Among them, 22 (45.9%) were AFB positive confirmed cases, 12 (25.0%) were AFB negative clinically diagnosed cases before treatment and 14 (29.1%) were clinically diagnosed cases on treatment. Age and sex matched 33 controls were also included, of which 19 (57.6%) were healthy and 14 (42.4%) were sick with non-specific pulmonary infection. Overall sensitivity and specificity of ELISA were 60.42% & 96.97% (p<0.001) and those of MycoDot as 72.92% & 93.94% (p<0.001). Rate of both ELISA and MycoDot positive were higher among clinically diagnosed cases on treatment with respective values as 71.42% and 85.71%. Respective values among AFB positive confirmed TB cases were 68.18% and 72.72%. As, both ELISA and MycoDot yielded be used as a confirmatory test for TB.  相似文献   
96.
The increasing use of ureteric stents including permanent ones is not without their own set of problems. The authors describe the difficulties encountered and a novel technique to reposition a permanent ureteric stent migrated into the kidney with an illustrated case. The same technique can also be applied to a-traumatically remove the stent if required.  相似文献   
97.
Abstract Bipartite patella fracture with quadriceps rupture is an unusual injury. It is quite often mistaken as an avulsion fracture of patella, and the X-ray of contra-lateral knee is useful for diagnosis, and appropriate treatment should be decided at the time of surgery. We report a single case of this entity in which bipartite patella fracture was misdiagnosed initially as a patellar fracture.  相似文献   
98.
The isolation and characterization of glutamic acid decarboxylase from Listeria monocytogenes has been described. Effects of various concentrations of glutamic acid as a substrate and pyridoxal phosphate as coenzyme on the activity of the partially purified enzyme have been examined and their Km and Vmax values determined. The enzyme exhibits relatively higher activity in 0.1 M pyridine-pyridine hydrochloride buffer with a pH value of 4.6.  相似文献   
99.
100.
Riluzole is the only FDA-approved drug to treat amyotrophic lateral sclerosis, but its long-term effects on motoneurons are unknown. Therefore, we treated primary mouse spinal cord cultures with 2 μM riluzole for 4-9 days and then used whole cell patch clamp to record the passive and active properties of both wild-type and SOD1(G93A) motoneurons. At this concentration, riluzole blocks >50% of the sodium component of a persistent inward current that plays a major role in determining motoneuron excitability. Prolonged riluzole treatment significantly decreased the amplitude of the persistent inward current. This effect was specific for SOD1(G93A) motoneurons, where the amplitude decreased by 55.4%. In addition, prolonged treatment hyperpolarized the resting membrane potential as well as the voltage onset and voltage maximum of the persistent inward current (~2-3 mV in each case). These effects appeared to offset one another and resulted in no change in the firing properties. In a subset of cells, acute reapplication of 2 μM riluzole during the recording decreased repetitive firing and the persistent inward current, which is consistent with the normal effects of riluzole. The downregulation of the persistent inward current in response to prolonged riluzole administration is in contrast to the strong upregulation of this same current after descending neuromodulatory drive to the cord is lost following spinal injury. This dichotomy suggests that decreased activation of G protein-coupled pathways can induce upregulation in the persistent inward current but that direct channel block is ineffective.  相似文献   
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