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101.
The mass fraction of certain elements was measured in isolated granulocytes and isolated granulocyte granule fractions from patients with active inflammatory arthritides (N=6) and healthy controls (N=6). The patients had significantly increased amounts of Ca in the granulocytes, in the specific and light azurophil granules, but normal Ca amounts in the dense azurophil granules. Sr was below the detection limit in the granulocytes and granule fraction from controls, but it appeared in high concentrations in the granulocytes and all granule fractions from the patients. The patients had considerably increased granulocyte amounts of Mn but only slightly increased Mn concentrations in the specific granules. Mn was not detectable in azurophil granules from patients and controls. A prominent accumulation of Fe was seen in the granulocytes from the patients, together with an Fe accumulation in the specific granules. Fe was below the detection limit in azurophil granules from patients and controls. The patients had reduced granulocyte Zn and reduced amounts of Zn in the dense and light azurophil granules but normal Zn amounts in the specific granules. The results obtained indicate that (1) the granulocyte accumulation of Ca, Sr, and Fe observed during chronic inflammation is associated with corresponding granule accumulation of these metals; (2) the considerable Mn accumulation in granulocytes during inflammation is not localized in their granules; and (3) the granule subpopulations differ in their capacity to store certain metals.  相似文献   
102.
BACKGROUND: Although diurnal variation of mood is a widely recognized symptom of depression, the clinical, neurobiological and psychopharmacological significance of this symptom has not previously been reported. METHOD: A total of 195 depressed out-patients underwent a detailed clinical and neurobiological assessment, and were then randomized to treatment with either fluoxetine or nortriptyline. RESULTS: Of the 195 depressed patients, 62 had a pattern of reversed diurnal variation (i.e. worse in the evening). Those with reversed diurnal variation had a poorer response to a serotonergic anti-depressant, were less likely to have bipolar II disorder, had a higher tryptophan: large neutral amino acid ratio and had different allele frequencies of the polymorphisms in the promoter region of the serotonin transporter. CONCLUSIONS: These findings raise the possibility of serotonergic influence on diurnal variation, and that the symptom of reversed diurnal variation is of relevance to antidepressant prescribing.  相似文献   
103.
Rats were sympathetically denervated on one side by avulsion of the superior cervical ganglion either immediately after birth (within 4 hr) or when the salivary glands were fully developed. Nine weeks after ganglionectomy the parotid glands were subjected to microscopical studies. As shown by the lack of specific fluorescence, sympathetic denervation caused an almost total depletion of catecholamines in the acini. This was further substantiated at the electron microscopic level using KMnO4 as fixative. No alterations in either gland weight or in acinar cell size were noticeable after adult sympathectomy. On the other hand, neonatal denervation caused a decrease in gland weight as well as acinar cell hypotrophy. The mean volume of individual acinar cells was reduced by roughly 25% and the granule volume density by about 50%. Also the mean volume of individual granules was decreased. These findings indicate an important role for the sympathetic nerve system in the maturation of the rat parotid gland.  相似文献   
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By hypothesis: 1.) lipid-pteridines and lipid-nucleotides, while fixed in the external side of membranes at the ends of nerve cells, bind neurotransmitters and perhaps opiates; 2.) during their normal metabolism in animals they are cleaved by phospholipases into pteridines and nucleotides which act as 2nd messengers for opiates. These 2nd messengers, some with tri-iodo-thyronine, act by sandwiching about circulating neurotransmitters; 3.) dinucleotides containing neopterin are specific 2nd messengers for steroids; and 4.) lipid-RNAs are the molecular locations in the brain which contain memories.  相似文献   
106.
A llama single domain antibody (dAb) library designed and constructed to contain only heavy chain antibody variable domains (V(H)Hs) also contained a substantial number of typical conventional antibody heavy chain variable sequences (V(H)s). Panning the library against two carbohydrate-specific antibodies yielded anti-idiotypic dAbs and enriched solely for sequences from the V(H) subpopulation of the library. The conventional antibody origin of these V(H)s was confirmed by using oligonucleotide probes, specific for the enriched V(H)s, to identify the parental sequences in the message employed in library construction. Surprisingly, these V(H) dAbs, which are produced in high yield in Escherichia coli, are highly soluble, have excellent temperature stability profiles and do not display any aggregation tendencies. The very close similarity of these molecules to human V(H)s makes them potentially very useful as therapeutic dAbs.  相似文献   
107.
Circulating angiotensin-1-converting enzyme (ACE) is a highly heritable trait, and a major component of the genetic variance maps to the region of the ACE gene. The strong effect of the locus, and the interest in ACE as a candidate gene for cardiovascular disorders, has led to extensive investigation of its relationship to the ACE phenotype, providing one of the most complete examples of quantitative trait locus (QTL) analysis in humans. Resequencing of ACE followed by haplotype analysis in families of British and French origin has shown that the genetic variants that are primarily associated with the ACE trait map to an 18 kb interval flanked by two intragenic, ancestral recombination breakpoints. This critical interval contains dozens of ACE-associated variants in Caucasians, but identification of which of these directly influence ACE concentration is ambiguous because of the almost complete linkage disequilibrium in European populations. In a complementary sequencing and genotyping study of individuals from West African families, we show that this population has much greater haplotype diversity across the gene. Through analysis of the contrasting relationships of the trait phenotype with haplotypes that carry different allelic combinations from those observed in Caucasians, we demonstrate that (at least) two major intragenic sites within the critical interval and (at least) one minor promoter site are associated with the ACE quantitative trait through additive effects. These results point to the importance of analysing diverse populations with different gene genealogies in gene-association studies.  相似文献   
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Multiscale structure of sheet nacre   总被引:20,自引:0,他引:20  
This work was conducted on Pinctada maxima nacre (mother of pearl) in order to understand its multiscale ordering and the role of the organic matrix in its structure. Intermittent-contact atomic force microscopy with phase detection imaging reveals a nanostructure within the tablet. A continuous organic framework divides each tablet into nanograins. Their shape is supposed to be flat with a mean extension of 45nm. TEM performed in the darkfield mode evidences that at least part of the intracrystalline matrix is crystallized and responds like a 'single crystal'. The tablet is a 'hybrid composite'. The organic matrix is continuous. The mineral phase is thus finely divided still behaving as a single crystal. It is proposed that each tablet results from the coherent aggregation of nanograins keeping strictly the same crystallographic orientation thanks to a hetero-epitaxy mechanism. Finally, high-resolution TEM performed on bridges from one tablet to the next, in the overlying row, did not permit to evidence a mineral lattice but crystallized organic bridges. The same organic bridges were evidenced by SEM in the interlaminar sequence.  相似文献   
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