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排序方式: 共有6942条查询结果,搜索用时 15 毫秒
41.
42.
G W Muller J C Culberson G Roy J Ziegler D E Walters M S Kellogg S S Schiffman Z S Warwick 《Journal of medicinal chemistry》1992,35(10):1747-1751
N-(4-Cyanophenyl)-N'-(2-carboxyethyl)urea (2), an analogue of suosan [1,N-(4-nitrophenyl)-N'-(2-carboxyethyl)urea], is a known high-potency sweetener derived from beta-alanine. Sulfonic and phosphonic acid analogues of 2 were prepared to develop structure-activity relationships through modification of the carboxylic acid region of this family of sweeteners. Neither of the carboxylic acid replacements resulted in sweet analogues. However, we found that N-(4-cyanophenyl)-N'-[(sodiosulfo)methyl]urea (7) is an antagonist of the sweet taste response. The bitter taste response to caffeine, quinine, and naringin was also antagonized. Antagonist 7 was found to inhibit the sweet taste perception of a variety of sweeteners. Antagonist 7 had no effect on the sour or salty taste response. 相似文献
43.
C Alonso-Vega N Wauters D Vermeylen M F Muller E Serruys 《Journal of clinical microbiology》1997,35(1):286-287
We report the case of a 20-day-old full-term baby, born to a mother who had had an uncomplicated pregnancy and delivery, who died 13 days after the onset of meningitis. Mycoplasma hominis was the sole agent repeatedly recovered from cerebrospinal fluid and from postmortem brain tissue. 相似文献
44.
J D Tempé J J Muller J Schieber M Hasselmann P Lutun P Kieffer F Schneider 《Revue de pneumologie clinique》1987,43(6):300-305
From a series of 50 patients with acute decompensation of chronic obstructive lung disease (38 of whom were treated by mechanical ventilation), the authors demonstrate the prognostic value of an easily obtained parameter of respiratory function: the vital capacity restitution curve (VCRC). From daily measurements of vital capacity, beginning on the day of admission, a graph is constructed which shows an initial period of increase in the degree of restitution, followed by stabilization of the values. An analysis of the various parameters embodied in this graph provides information about the prognosis. Such graphs can be divided into 3 zones of prognostic value: a favourable zone, an intermediate zone (mediocre survival with or without mechanical ventilation) and an unfavourable zone (death during the acute phase). Although a favourable prognosis can be made after 4 days of observation and almost always by the 10th day, an unfavourable prognosis cannot be made before the 21st day. 相似文献
45.
D Campion M Leboyer D Hillaire L Halle P Gorwood B Cavelier M F Soufflet T d'Amato B Muller C Kaplan 《Psychiatry research》1992,41(2):99-105
The role of the human histocompatibility complex (HLA) in the pathogenesis of schizophrenia has been suggested in previous reports. We conducted a genetic study in 33 new families. Our linkage analysis, which used the affected sib-pair method, did not provide evidence for nonrandom assortment. Moreover, the results of an association study using the "haplotype relative risk" method failed to confirm the positive association between HLA A9 and schizophrenia. Taken together, our data did not support any relationship of HLA type to schizophrenia. 相似文献
46.
Taillandier A Zurutuza L Muller F Simon-Bouy B Serre JL Bird L Brenner R Boute O Cousin J Gaillard D Heidemann PH Steinmann B Wallot M Mornet E 《Human mutation》1999,13(2):171-172
Hypophosphatasia is a rare inherited disorder characterized by defective bone mineralization and deficiency of serum and tissue liver/ bone/kidney tissue alkaline phosphatase (L/B/K ALP) activity. We report the characterization of tissue-nonspecific alkaline phosphatase (TNSALP) gene mutations in a series of 9 families affected by severe hypophosphatasia. Fourteen distinct mutations were found, 3 of which were previously reported in the North American or Japanese populations. Seven of the 11 new mutations were missense mutations (M45L, R119H, G145V, C184Y and H154Y, D289V, E459K), the four others were 2 single nucleotide deletions (544delG and 1172delC), a mutation affecting donor splice site (862 + 5A) and a nonsense mutation (R411X). 相似文献
47.
Hormonal fluctuations associated with the menstrual cycle influence
appetite control and eating behaviour. Energy intake varies during the
reproductive cycle in humans and animals, with a periovulatory nadir and a
luteal phase peak. Patterns of macronutrient selection show less
consistency but a number of studies report carbohydrate cravings in the
premenstrual phase, particularly in women with premenstrual syndrome. The
cyclical nature of food cravings are frequently, but not invariably,
associated with depression. Fluctuations in appetite, cravings and energy
intake during the menstrual cycle may occur in parallel with cyclical
rhythms in serotonin, which can be accompanied by affective symptoms. The
premenstrual phase can be considered as a time when women are especially
vulnerable to overconsumption, food craving and depression; this is often
associated with low serotonin activity.
相似文献
48.
49.
Presentation of antigen to suppressor cells by a dimethylbenz (a) anthracene-resistant, Ia-positive, Thy-1-negative, I-J-restricted epidermal cell 总被引:1,自引:0,他引:1
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The epidermal layer of the skin contains class II major histocompatibility (MHC)-positive antigen-presenting cells (APC), the most well characterized population being Langerhans' cells (LC). The chemical carcinogen 7,12 dimethylbenz (a) anthracene (DMBA) depletes about two-thirds of these cells from murine epidermis, and contact sensitizers applied to DMBA-treated skin induce specific immunological tolerance. This tolerance results from epidermal cells migrating to local lymph nodes within 3-6 hr after contact with antigen where they present the antigen to suppressor cells. Here we demonstrate that this epidermal cell which activates suppressor cells is a class II MHC-positive. Thy-1-negative, I-J-restricted APC. Hence at least two types of class II MHC-positive epidermal cells migrate to local lymph nodes and present antigen to lymphocytes; LC, which are sensitive to the effects of DMBA and activate helper lymphocytes, and another, which is resistant to DMBA and activates suppressor cells in an I-J-restricted manner. During the early stages of carcinogenesis any antigen present in the epidermis would be presented only by the cells which activate suppressor lymphocytes, resulting in tolerance induction. This may enable neoplastic cells to avoid the initiation of anti-tumour immunity. 相似文献
50.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献