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51.
The results of analysis of auditory brain- stem evoked responses (ABRS) are reported in 173 patients with delayed speech (DS). The mean age of the patients is 4.6 years (age ranges from 1.4 years to 10 years). The patients were classified into 5 groups based on ABR findings:
–  Group I (62 patients) had normal hearing threshold and peak- interpeak latencies. The mean amplitude of wave I was however, not significantly low (p < 0.03).
–  Group II (27 patients) had an increased hearing threshold (40 dB), mild delay in the mean absolute peak latency of wave I (p < 0.03), decreased I– IV interval (p < 0.03), but highly significant reduction of wave I amplitude (p < 0.004). There is also a significant latency delay (p < 0.001) and amplitude reduction (p < 0.05), when this wave is compared with that a Group I (as control). These observations are suggestive of mild degree of peripheral hearing deficit in this group.
–  Group III (49 patients) had gross ABR abnormalities of various nature and hence may be sub- grouped into (a) SNHL cochlear type (55%) (b) SNHL retrocochlear type (4%) and (c) severed degree of SNHL undecisive group (41%). Ten patients (2.7%) among the sub- group (a) had unilateral hearing loss and another 3 had Down’s syndrome.
–  Group IV (conductive deafness) had an increased hearing threshold and shifting of ABR waves towards right with normal I– V interval. Only 6 patients were found in this group. It may be that conductive deafness is less important as a cause.
–  Group V (29 patients) had no responses at repeated ABR studies even at higher intensity of 95 dB, the ABR studies of this group correlates with the clinical evaluation of profound deafness. The delayed speech development in 84 patients (from Groups III, IV and V) may be caused by severe degree of hearing deficit as indicated by marked ABR abnormalities. If the mild peripheral hearing loss in Group II is added to the above groups, ABRs could identify 64.6% of our patients with hearing deficit. Hence, ABR test is most reliable and sensitive diagnostic test in detecting hearing loss, a common cause of delayed speech development in children.
  相似文献   
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The uptake of chloroform into hairless rat's stratum corneum after application of the neat solvent directly to the skin has been studied. Tape stripping was used to determine amounts deposited within the stratum corneum and also the clearance of the compound from the skin following varied levels of exposure. Three minutes exposure to neat chloroform was adequate to achieve a limiting accumulation in the stratum corneum and thus it appears to take this long for the gradient of chloroform to be established fully across this structure. There was indication of progressively deeper penetration of chloroform as the exposure time was increased from 1 to 8 minutes. Local irritation and a loosening of the superficial layers of stratum corneum were apparent with as little as 2 minutes of exposure to the solvent and were exacerbated with further increases in exposure duration. Following exposure, clearance of the solvent from the skin surface was rapid. Interestingly, the rate of clearance, as followed by stripping, was comparable on live and freshly euthanized rats. This implies that once the exposure is terminated evaporation from the surface, and not systemic uptake by way of the local vasculature, is the predominant means of clearance at an open surface.  相似文献   
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Ligands for the CCR1 receptor (MIP-1alpha and RANTES) have been implicated in a number of chronic inflammatory diseases, most notably multiple sclerosis and rheumatoid arthritis. Because these ligands share a common receptor, CCR1, we sought to discover antagonists for this receptor as an approach to treating these disorders. A novel series of 4-hydroxypiperidines has been discovered by high throughput screening (HTS) which potently inhibits the binding of MIP-1alpha and RANTES to the recombinant human CCR1 chemokine receptor. The structure-activity relationships of various segments of this template are described as the initial HTS lead 1 was optimized synthetically to the highly potent receptor antagonist 6s. This compound has been shown to have at least 200-fold selectivity for inhibition of CCR1 over other human 7-TM receptors, including other chemokine receptors. In addition, data obtained from in vitro functional assays demonstrate the functional antagonism of compound 6s and structurally related analogues against the CCR1 receptor in a concentration dependent manner. The discovery and optimization of potent and selective CCR1 receptor antagonists represented by compound 6s potentially represent a novel approach to the treatment of chronic inflammatory diseases.  相似文献   
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An extensive iodine deficiency disorders survery was conducted in Bangladesh in 1993 to assess the latest iodine nutriture status of the country. The clinical variables of the survey were goitre and cretinism, and the biochemical variable was urinary iodine. The “EPI-30 cluster” sampling methodology was followed for selecting the survey sites. In each survey site, the study population consisted of boys and girls, aged 5–11 years, and men and women, aged 15–44 years, in about equal populations. the total number of survey sites was 78 and the total number of respondents was 30 072. The total number of urine samples was 4512 (15% sub-sample). The current total goitre rate (grade 1+grade 2) in Bangladesh is 47.1% (hilly, 44.4%; flood-prone, 50.7%; and plains, 45.6%). The prevalence of cretinism in the country is 0.5% (hilly, 0.8%; flood-prone, 0.5%; and plains, 0.3%). Nearly 69% of Bangladeshi population have biochemical iodine deficiency (urinary iodine excretion [UIE]<10 mg/dl) (hilly, 84.4; flood-prone, 67.1%; and plains 60.4%). Women and children are more affected than men, in terms of both goitre prevalence and UIE. The widespread severe iodine deficiency in all ecological zones indicates that the country as a whole is an iodine-deficient region. Important recommendations of global interest are made from the experience of the survey. An erratum to this article is available at .  相似文献   
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