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Exposure to cadmium via the diet is known to depend to a large extent on the intake of cereal grains, particularly the high-fibre fractions of wheat. Subjects with low iron status absorb more cadmium than those with better iron status. The purpose of the present study was to determine to what extent cadmium accumulation in human placenta is affected by the intake of grain fibre and maternal iron status during pregnancy. Thirty-nine pregnant women participated in the study. In each trimester the women were requested to complete a dietary history and to allow blood samples to be taken for haemoglobin, serum ferritin and serum thiocyanate determinations, the latter as a marker for smoking. At delivery the whole placenta was taken for the determination of the cadmium concentration. The 32 women who had serum thiocyanate levels less than 70 mumol/l, who had completed at least one dietary history and from whom a blood sample was obtained in the third trimester, were included in the final statistical analyses. In the group of women who consumed less than the median intake of grain fibre and had more than 15 micrograms ferritin/l serum in the third trimester, the placenta cadmium concentration was nearly half that in the placentae of women who had consumed more grain fibre or had lower iron status in late pregnancy.  相似文献   
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Summary The aim of the present study was to investigate the discriminative power of a series of variables (including determination of depressive symptomatology by means of a visual analogue scale, determination of personality traits by means of the Karolinska Scales of Personality, determination of monoamine metabolites in CSF, platelet MAO activities, serum cortisol before and after dexamethasone suppression and urinary melatonin) in differentiating (a) chronic pain patients from healthy subjects, and (b) patients with idiopathic pain syndromes from patients with neurogenic pain syndromes. Separately each of the measures gave a significant but often low contribution to the discrimination, while a combination of several measures gave a complete discrimination both between healthy subjects and patients with chronic pain syndromes and between patients with idiopathic and neurogenic pain syndromes, respectively.Supported in part by grants from the Swedish Medical Research Council (grants no. 3371, 4145 and 5740) and by a grant from Stiftelsen Söderström-Königska Sjukhemmet  相似文献   
5.
Changes in latencies of the visual evoked response (VER) during early post-natal development were examined in protein-deprived (PD) rats. The evoked response to light-flash stimulation was recorded in the dorsal lateral geniculate nucleus (dLGN) and on the surface of the visual cortex. In control rats, latencies of the cortical VER decreased rapidly up to 20 days and slowly thereafter. In PD rats, the latencies of the cortical VER were increased by 10-15 ms at 17 days; the developmental decrease was delayed by approximately 3 days. After 20 days, PD rats also went into a phase with slow decrease of the latencies, and the onset latency of the cortical VER was still increased by some 10 ms at 26/27 days. At this age, PD rats showed an increase in the latencies of the VER in the dLGN which was of similar magnitude to that in the cortical VER, indicating that alterations were more marked in the peripheral parts of the visual system at this stage of development. The findings are in agreement with previous studies indicating that there is a delay of visual system development in PD rats before 20 days. A maturational event which turns rapid into slow development at approximately 20 days in both C and PD rats turns this delay into a distortion of development. The delays and distortions of visual system development may be one causative factor for the functional deficit present in the visual cortex of adult PD rats.  相似文献   
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It was recently shown that an increase in latency of the cortical visual evoked response (VER) seen in young malnourished animals persists in adult rats given a low protein diet. In the present paper the VER latencies of the specific visual pathway were measured in order to establish the level at which the latency increase occurs in protein-deprived rats. The VER in the dorsal lateral geniculate nucleus (dLGN) showed no significant differences to onset or peak latencies between control (C) and the protein-deprived (PD) rats. The dLGN activity was higher in C rats than in PD rats. Late components differed in median values between the two groups, but the individual variations were large. Generally, the VER of the dLGN in PD rats was more stereotype compared with the C rats. Intracortical VER at a depth of 0.4-0.5 mm showed a small negative component of short onset latency in both C and PD rats. This component preceded the onset of the initial positivity recorded from the cortical surface by 1-2 ms in C rats and by 3-6 ms in PD rats. Following electrical stimulation of the dLGN, no differences in onset latency of the first cortical activity (monosynaptic response) were recorded between C and PD rats, whereas later activity was significantly delayed in PD compared with C rats. The laminar potential pattern was less distinct in PD compared with C rats, and the late components of the evoked response from deep cortical layers were markedly attenuated or lacking.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
Transgenic mice expressing a defined microbial antigen from central nervous system (CNS) cell type-specific promoters can be utilized to investigate the consequences of induction of peripheral immune responses to foreign antigens produced by different CNS cell types. Immunization of mice expressing β-galactosidase (β-gal) in astrocytes with this protein resulted in antigen-dependent infiltration of the CNS by mononuclear cells, principally CD4+ T lymphocytes and monocyte/macrophages. The perivascular and intraparenchymal infiltrates, which were located predominantly in the hippocampal formation and cerebellum, the areas of highest β-gal expression, were associated with astrocytosis, microgliosis, and a generalized increase in blood-brain barrier permeability. The resemblance of these pathological changes to aspects of human immune inflammatory CNS disorders e.g. multiple sclerosis, suggests that an initiating step in the process by which such complex diseases are produced could be the induction of peripheral immune responses to antigens expressed in astrocytes.  相似文献   
8.
Abstract Maxillary and mandibular anterior permanent teeth in 38 children aged 7–12 years were examined 2 × with an interval of 2 years to determine whether spontaneous facial/lingual tooth position changes were related to alterations of the widths of keratinized and attached gingiva and the clinical crown height. Measurements included dental plaque, gingival inflammation, probing depth, and width of keratinized and attached gingiva. In addition, study casts from the baseline and 2-year examinations were used to measure clinical crown height and tooth position. The results showed that significant alterations in the widths of the keratinized and attached gingiva took place when the teeth changed positions in facial or lingual directions. The changes in gingival widths could to some extent be coupled to changes in clinical crown height. In teeth moving lingually, the gingival widths increased and the clinical crown height decreased. In teeth moving facially, the gingival widths decreased, and the facial gingiva sometimes receded. These gingival alterations call for examination of the facial gingiva as part of the monitoring of the development of the permanent dentition.  相似文献   
9.
This study was undertaken to assess the frequency of significant esophageal involvement in the Zollinger-Ellison syndrome (ZES). In a consecutive series of 24 patients with this disease, 9 (37%) showed endoscopic evidence of acid-induced esophageal lesions ranging from erosive inflammation to ulceration with massive bleeding, severe stricture formation, and perforation. In 3 cases, pronounced esophagitis was known 1–5 years before the underlying disease was diagnosed. Severe esophageal complications developed despite treatment with antisecretory drugs. It is emphasized that the best way to limit such complications is by excision of the underlying gastrin-secreting tumor(s) when possible.
Resumen El presente estudio fue emprendido con el propósito de determinar la frecuencia de afección ácido péptica significativa del esófago en pacientes con síndrome de Zollinger-Ellison. En una serie de 24 pacientes consecutivos con esta enfermedad, 9 (37%) exhibieron evidencia endoscópica de lesiones esofágicas inducidas por ácido, las cuales variaron entre inflamación erosiva y ulceración con sangrado masivo, estrechez severa, y perforación. En 3 pacientes se conocía la existencia de esofagitis severa entre 1 y 5 años antes del diagnóstico de la enfermedad de base. Se desarrollaron graves complicaciones esofágicas a pesar del tratamiento con drogas antisecretorias en 3 pacientes. Se hace enfasis en que la mejor manera de disminuir tales complicaciones es mediante la resección del tumor(es) secretor de gastrina, cuando ello sea posible.

Résumé Nous avons entrepris cette étude pour établir la fréquence de participation oesophagienne dans le syndrome de Zollinger-Ellison. Pour une série de 24 patients présentant cette maladie, 9 (37%) avaient à l'endoscopie des lésions oesophagiennes dues à l'acidité allant de l'érosion inflammatoire à l'ulcération avec saignement important, sténose sévère, et perforation. Dans 3 cas, une oesophagite importante était connue 1–5 ans avant que la maladie sous-jacente soit diagnostiquée. Des complications oesophagiennes sévères se sont produites malgré le traitement antisécrétoire. Nous insistons sur le fait que le meilleur moyen de limiter ces complications est d'exciser chaque fois que possible la ou les tumeurs sous-jacentes sécrétant la gastrine.


Presented at the International Association of Endocrine Surgeons in Toronto, Ontario, Canada, September, 1989.

Supported by grants from the Swedish Medical Research Council, the Swedish Society of Medicine, the Anders Otto Swärd Foundation, and the Surgery Foundation of Skövde Central Hospital.  相似文献   
10.
We report a case of renal cell carcinoma within a simple renal cyst in the lower pole of the right kidney. Excretory urography showed a mass and ultrasonography revealed multiple renal cysts with a solid component arising from the wall in 1. This finding also was visualized by computerized tomography. Analysis of the cystic fluid showed a high cholesterol level but negative cytological results. At operation a 7 mm. tumor arose from the wall of the cyst. Histopathological examination showed grade 3 renal cell carcinoma with an aneuploid deoxyribonucleic acid content.  相似文献   
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