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881.
Mannan-binding protein (MBP) is a lectin which, upon binding to certain carbohydrates, activates the classical pathway of complement without the involvement of antibody or C1q. Deficiency of the MBP is associated with an opsonic defect and recurrent infections during early life. An amino acid substitution in the exon 1 at codon 54 in the MBP gene (GGC [glycine] to GAC [aspartic acid]) has been shown to be closely associated with low MBP concentration in Caucasoids. The gene frequency of the mutant allele in this population has been estimated at 0.13. In the study described here, we investigated the association between the mutant allele and MBP protein concentration in Eskimos from East-Greenland and black Africans from the Baringo District in Kenya. The frequency of the GAC allele was identical in Eskimos and Caucasoids (0.13). No overlap with regard to MBP concentration between the genotypes was found in the Eskimos. In contrast, the Africans revealed a low frequency of the GAC allele (0.009). However, the median MBP protein concentration was approximately 5 times lower among the Africans than the Eskimos. In 12.6% of the Africans and in 2.5% of the Eskimos, MBP was undetectable. Thus, MBP deficiency is the most frequent immunodeficiency so far described. The high prevalence of MBP deficiency among healthy individuals indicates that MBP deficiency also confers some selective advantages. We advance the hypothesis that MBP deficiency is maintained in populations because MBP deficiency decreases the infectivity of some intracellular micro-organisms which are dependent on opsonization.  相似文献   
882.
A CMEC which occurred within the right maxillary canine-third molar region of a 34-year-old male was presented. The clinical symptoms were swelling and pain. Radiologically the lesion looked like an ameloblastoma or residual cyst. Hemimaxillectomy was the treatment. No evidence of recurrence has been observed for ten months after the operation.  相似文献   
883.
The mode of adsorption of salivary proteins at air/liquid interfaces was studied by using the drop volume technique to measure the kinetics of surface tension decay of aqueous salivary solutions. Adsorption of salivary proteins from whole saliva was fast, with a plateau value of the surface tension of 43 (+/- 2) mNm-1. As the concentration of saliva was reduced, the plateau value of surface tension increased and was achieved more slowly. The reduction in surface tension of aqueous solutions was larger for salivary proteins than for many other proteins reported.  相似文献   
884.
Koilocytosis is commonly regarded as indicative of human papilloma virus infection in the uterine cervix. In 1987 morphologically similar changes were reported in bladder tumours. This is confirmed in the present study, the incidence here being 65%. In addition the incidence of koilocytic change was shown here to increase from non-infiltrative WHO grade I to infiltrative WHO II lesions, and to be more common in bladder lesions in women with cervical koilocytosis. The latter is in keeping with our previous report that the incidence of koilocytosis in the cervix of patients with bladder neoplasia is higher than expected in the general population, adding support to the hypothesis that both lesions may be virus-related.  相似文献   
885.
We report the case of a 75-year-old-woman who presented with bilateral scalp ulcerations and blindness, accompanied by severe headache and scalp tenderness, due to bilateral temporal arteritis without systemic involvement. A biopsy taken from the border of an ulceration showed evidence of giant cell arteritis. She was treated with oral prednisone, 60 mg per day. The ulcerations healed in a few weeks but the vision loss was irreversible. This case highlights for temporal arteritis the importance of accurate and timely diagnosis as well as the need for prompt therapy with systemic steroids in order to avoid major complications, namely loss of vision. It also demonstrates that scalp necrosis and ulcerations are skin signs associated with a poor prognosis.  相似文献   
886.
A systematic review on the treatment of giardiasis   总被引:5,自引:0,他引:5  
To assess the efficacy of treatment of parasitological excretion of cysts and trophozoites and symptoms of patients with giardiasis, a systematic review of published randomized clinicial trials was conducted through extensive searches in Medline, Embase and Current Contents from 1966 till 1996 as well as manual reviews of 28 journals. The methodological quality of all trials was assessed by guidelines of the Cochrane Collaboration. Thirty‐one trials were included, only one of which had no serious methodological flaws. The mean score of parasitological examination was 4.8 out of a possible 15. There was a considerable effect in cure rate of treatment versus placebo (odds 9.3, 95%CI 4.69–18.4), but all 3 trials in this comparison had serious flaws. Metronidazole treatment over more than 3 days seems to achieve a better parasitological cure rate than other long treatment courses (pooled odds 2.6, 95% 1.7–3.8), but trials are clinically and statistically heterogeneous. Single‐dose therapy is as effective as longer treatment courses (pooled odds 0.67, 95% 0.31–1.44). Within the single‐dose regimens tinidazole (2 g) reaches a higher parasitological cure rate than other short therapies (pooled odds 55, 95% CI 3.7–8.3) with relatively few side‐effects. Placebo‐controlled trials with parasitological and clincial outcomes are needed.  相似文献   
887.
S M Samuelsson  A Ekbom  M Zack  C G Helmick    H O Adami 《Gut》1991,32(12):1526-1530
To examine socioeconomic factors, dietary and other personal habits, and medical history as risk factors for ulcerative colitis, we studied 167 (98%) of all prevalent cases of ulcerative colitis diagnosed in Uppsala county from 1945 to 1964 and 167 age and sex matched population controls. Ulcerative colitis patients were less likely than controls to be current cigarette, pipe, or cigar smokers (odds ratio (OR) = 0.44; 95% confidence limits (CL) = 0.25-0.78), but more likely to have symptoms induced by drinking milk (OR = 4.63; 95% CL = 2.15-9.93). Patients with ulcerative colitis do not differ in most of the socioeconomic, dietary and personal habits compared with the background population.  相似文献   
888.
An 8-year-old girl presenting in hypoglycaemic coma was shown to have isolated deficiency of adrenocorticotrophic hormone (ACTH) secretion. Failure to secrete ACTH in response to intravenous administration of synthetic ovine corticotrophin-releasing factor (CRF-41) suggests that this disorder was due to a primary pituitary defect, rather than of hypothalamic origin.  相似文献   
889.
Pulmonary Function in Survivors of Wilms' Tumor   总被引:1,自引:0,他引:1  
The respiratory status of 47 patients surviving childhood Wilms' tumor was studied. The group that had receivedflnnk irradiation (which impinges on the lower lung) (n - 17) had a sisnijGantly lower mean percent predicted for forced expiratory volume in one second, residual volume, and total lung capaci(v when compared to those who had received no irradiation (n - 23). Those patients who had received whole-lung irradiation (n - 3) had sisnijicantly lower transfn. foctor for carbon monoxide and gas transfer per unit lung volume whm compared to the nonirradiated group (n - 23). There was no sipiftiant dimue in the prevalence of respiratory symptoms between the three groups. Patients receiving any form of radiotherapy for Wilms' tumor may have abnormulities o f pulmonary function and should have pulmonary function tests performed as part o f their long-tmn follow-up.  相似文献   
890.
One of the main obstacles for the introduction of PCR method to identify HIV1 proviral DNA in routine diagnostic laboratories is the use of radiolabelled oligodeoxynucleotide probes. Nonradioactive labelled probes have several advantages over radioactive labelling: they are stable for over 1 year, they can be produced easily in large amounts and they are safe. Polymerase chain reaction is an efficient and simple method to produce vector free inserts to use as probes. In this paper we describe a procedure for labelling DNA probes with digoxigenin-11-dUTP using the polymerase chain reaction. This non-radioactive labelling system was applied to detect HIV proviral sequences, amplified in vitro by PCR, from peripheral blood mononuclear cells DNA of infected subjects. We found identical sensitivities and specificities for probes synthesized with the non-radioactive and radioactive labelling procedures. The digoxigenin-11-dUTP can be efficiently incorporated during amplification of a DNA fragment using the polymerase chain reaction. This labelling and detection method proved to be specific, sensible and simple enough to be used in routine diagnostic laboratories for the detection of HIV1 infected individuals.  相似文献   
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