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101.
Mechanisms of zinc (Zn) toxicity are incompletely understood and data regarding potential endocrine alterations in Zn toxicity are scarce. To examine mechanisms of Zn toxicity, day-old chicks were pair-fed diets containing 5280 ppm (Hz) or 73 ppm (CON) Zn. Impaired postnatal growth, independent of feed consumption, and multiple endocrinopathies were observed following short-term (1-2 weeks) exposure to the high Zn diet. Reduced levels of serum cholesterol, high-density lipoprotein cholesterol, and growth hormone were associated with HZ feeding. Depressed levels of circulating thyroid hormones and histological evidence that follicle area of thyroids from HZ birds was 63% less than CON indicated that impaired growth of HZ birds may be caused, in part, by reduced thyroidal function. 相似文献
102.
Effect of Short-Term Ethanol Feeding on Rat Testes as Assessed by 31P NMR Spectroscopy, 1H NMR Imaging, and Biochemical Methods 总被引:2,自引:0,他引:2
Hassan Farghali Donald S. Williams Judith Gavaler David H. Van Thiel 《Alcoholism, clinical and experimental research》1991,15(6):1018-1023
31P Nuclear magnetic resonance (NMR) spectroscopy and 1H NMR imaging were used to examine the effect of short-term ethanol feeding on the rat testis. Weanling rats were pair-fed for 10 weeks either on ethanol containing liquid diet (36% ethanol of total calories) or a diet in which dextrimaltose was isocalorically substituted for the ethanol of the alcohol-containing diet. In vivo 31P NMR of the testes was used to determine the intratesticular pH and the relative concentrations of various phosphorus-containing metabolites. The integrity of the blood-testes barrier was evaluated using 1H NMR imaging following a gadolinium diethylene tetramine pentaacetic acid derivative (Gd-DTPA) administration as a vascular contrast agent. After the completion of NMR studies, the testis and the liver were freeze-clamped to allow for the assay of their adenosine-5'-triphosphate (ATP) contents. Serum was assayed for its content of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alcohol and testosterone. Ethanol feeding resulted in the following: (a) a reduction in the body weight (p less than 0.05), (b) a reduction in the testicular phosphodiesters (PDE) PDE/ATP ratio (p less than 0.05), (c) an increased change in the testis image intensity difference between pre- and post-iv Gd-DTPA images, (c) a reduction in the testicular and hepatic content of ATP, and (d) increased serum levels of AST and ALT.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
103.
104.
The results of conventional cerebrospinal fluid (CSF) investigations (CSF cell count, protein and glucose concentrations and Pandy's test for CSF globulin) obtained on admission and sequentially from weekly follow-up lumbar punctures for 4 weeks were evaluated in 99 children (median age 28 months) with stage II (50 children) and stage III (49 children) tuberculous meningitis. On admission, six children (6%) had a CSF cell count greater than 500 x 10(6)/l and nine (9%) a polymorphonuclear predominance. A CSF protein less than 0.8 g/l was found in 17 children (18%) of 97 in whom CSF protein was evaluated. Globulin was either absent or present as a trace only in 26 children (27%). CSF glucose was less than 2.2 mmol/l in 58 cases (60%) and less than 2.5 mmol/l in 67 (69%). In 63 children weekly CSF specimens obtained for the 1st 4 weeks of therapy showed an uninterrupted decline in cell count in 23 (37%), a fluctuating downward trend in 27 (43%) and a fluctuating upward trend in 13 (21%). Sequential CSF protein values in 57 children showed an uninterrupted rise in three (5%), a fluctuating upward course in 19 (33%), an uninterrupted downward trend in seven (12%), and a fluctuating downward course in 28 (49%). Of the 61 children in whom sequential CSF glucose concentrations were available, 11 (18%) experienced fluctuating concentrations, values falling to less than 2.2 mmol/l after being greater than 2.2 mmol/l on admission or after having risen to greater than 2.2 mmol/l.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
105.
Weyers'' ulnar ray/oligodactyly syndrome and the association of midline malformations with ulnar ray defects. 下载免费PDF全文
We describe a two generation family with variable ulnar and radial ray reduction and midline craniofacial abnormalities. The features suggest a diagnosis of Weyers' ulnar ray/oligodactyly syndrome originally described in two isolated cases. Syndromes of ulnar ray reduction are briefly reviewed and the relationship between limb bud and midline development discussed. 相似文献
106.
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108.
Harold O. Goodman Robert Brommage Dean G. Assimos Ross P. Holmes 《World journal of urology》1997,15(3):186-194
An examination of the urinary excretions of 101 normal subjects indicated that the major genetic influence on calcium excretion is a codominant pair of alleles giving rise to three phenotypes, low, intermediate and high (hypercalciuric) excretors. This inference was based on variance, Hardy-Weinberg and segregation analyses. Similar independent gene pairs also appear to influence oxalate and citrate excretion, A 3-locus Hardy-einberg table using estimates of gene frequencies derived from the study of normals suggests that only 3 or 4 leading genes are involved in oxalate stone disease. Strong candidate genes identified from molecular and physiological studies cannot be proposed at present, but it is assumed that they influence the transport of these ions in either the intestine, kidney or both organs. The identification of the genes involved should be facilitated by the reduction of dietary influences on urinary excretions through the use of formula diets. 相似文献
109.
Hershel Jick M.D. Marian Wald Myers P.A.-C. Alan D. Dean M.B. B.S. 《Pharmacotherapy》1995,15(2):176-181
Sulfasalazine (SASP) has often been reported to cause serious blood disorders, particularly agranulocytosis; however, little quantitative information is available to estimate the risk or to identify possible modifiers of the risk. We used comprehensive clinical information recorded on office computers by selected general practitioners in Britain to conduct a follow-up study of some 10,000 users of SASP and some 4000 users of mesalazine to estimate the risk of blood disorders associated with these drugs. Overall, the frequency of blood disorders attributable to SASP was 27/10,332 (2.6/1000 users). The risk for SASP users who were treated for arthritic disorders (6.1/1000 users) was some 10 times higher than that for users who were treated for inflammatory bowel disease (0.6/1000 users). There were no cases of blood disorders in users of mesalazine. 相似文献
110.
Jonathan E. Bishop Giles E. Santyr Frederick Kelcz Donald B. Plewes 《Journal of magnetic resonance imaging : JMRI》1997,7(4):716-723
The effect of keyhole data acquisition on quantitative analysis of dynamic MRI was examined. Experiments were performed retrospectively on raw data obtained from clinical dynamic contrast-enhanced breast imaging procedures. The effects of keyhole phase-encoding acquisition and type of reconstruction algorithm on the accuracy of derived quantitative parameters was assessed. Results indicate that the minimum keyhole size used should be restricted by the approximate minimum size of the expected lesions. Furthermore, reconstruction algorithms that offer improved image resolution do not circumvent this restriction. 相似文献