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1.
OBJECTIVES: To compare oestradiol and oestrone concentrations and bioavailability after a single dose and at a steady state during oral oestradiol valerate, transdermal oestradiol gel and transdermal oestradiol patch treatments. METHODS: Two open, randomised, cross-over studies were conducted. In the first study, 12 healthy postmenopausal women received 1.5 mg oestradiol as a transdermal gel or a 2 mg oestradiol valerate tablet daily for 14 days. In the second study, 15 postmenopausal women were treated for 18 days with 1.5 mg oestradiol gel or a transdermal patch releasing oestradiol 50 microg/24 h (replaced every 72 h). Venous blood samples for serum oestradiol and oestrone measurements with RIA were taken until 24 or 72 h after the first and last doses. RESULTS: The tablet and the transdermal gel yielded similar serum oestradiol profiles with a peak concentration 4-5 h after administration. The patch resulted in relatively stable oestradiol levels during the mid third of the wearing time whereas much lower levels were observed in the beginning and towards the end. There was no difference in the fluctuation between the peak and trough oestradiol levels between the gel (56 or 67%) and the tablet (54%) while the fluctuation was greater with the patch (89%). The bioavailability of oestradiol from the gel was 61% as compared with the tablet and 109% as compared with the patch. The gel was not bioequivalent with the tablet or the patch. CONCLUSIONS: The doses used of the transdermal gel and the patch roughly corresponded to each other with regard to the amount of oestradiol absorbed whereas the bioavailability from the tablet was significantly higher than from the gel. The lack of bioequivalence, the different serum oestradiol profiles and the large intersubject variability suggest that individual dose adjustments may be needed when changing administration form.  相似文献   

2.
The aim of this contribution is twofold: to honour Ivan Lefkovits with a short recollection of our scientific collaboration in the years 1972–1985 and a summary of our joint contribution to studies of the mechanisms and functions of the immune system and to acknowledge our long-lasting friendship. Ivan's limiting dilution microculture method was adapted to rabbit peripheral blood lymphocytes (PBL). The antibody produced in the responding cultures was shown to be electrophoretically homogeneous and, in rabbits heterozygous at the b locus, to express either one or the other allele. Thus, the antibody released in single microcultures was indeed the product of single B-cell clones and allelic exclusion, once achieved, was maintained throughout clonal proliferation. In the response to streptococcal polysaccharides, analysis of the clonotypes triggered in vitro provided information on mechanisms of clonal dominance. A two-stage culture system was established, where rabbit PBL were precultured at low cell density with antigen before being partitioned in limiting dilution cultures. This method provided a new tool for studies of various cellular aspects of the immune response. Moreover, it allowed the application of the limiting dilution analysis to PBL from unprimed animals. Later, the method was extended with success to human PBL, leading to studies of regulatory aspects of immunity in this species.  相似文献   

3.
Meckel's diverticulum, which is a remnant of the omphalomesenteric or vitelline duct, is the most common congenital abnormality of the gastrointestinal system. Urachal abnormalities, resulting from anomalous urogenital development, are not observed frequently and case reports are mainly represented in literature. The presence of these two congenital anomalies together is a very rare pathology. Complications arising from a Meckel's diverticulum or urachal remnant may clinically mimic acute appendicitis and other surgical pathologies. We report on a patient who underwent surgery for acute appendicitis when it was discovered that the symptoms were produced by a perforated Meckel's diverticulitis. In the course of the surgery, a urachal remnant was found to coexist with the diverticulum.  相似文献   

4.
A case of multicentric reticulohistiocytosis (MR) in a 24-yr-old woman is presented. MR is a rare disorder characterized by progressive polyarthropathy and a papulo-nodular skin rash. The diagnosis was established by histological examination of biopsies of erythematous nodules on the fingers which showed circumscribed collections of large mononuclear cells and multinucleate giant cells in the reticular dermis. These were embedded in a fine network of mature fibrous tissue with a scanty lymphocytic infiltrate. Histochemical, immunopathological and ultrastructural investigations confirmed that the large mononuclear cells had the properties of macrophages. The histopathological features of MR are reviewed in the light of current knowledge of macrophage physiology, and evidence for lymphocyte-histiocyte interactions in the pathogenesis of this bizarre granulomatous disorder is presented.  相似文献   

5.
The palatal epithelium of a monotreme, Tachyglossus aculeatus and a marsupial, Tarsipes spenserae were examined histologically and with the scanning electron microscope. Each animal possess keratinized palatal spines which although histologically similar, show significant differences in their external morphology. It is suggested that the spines in each case are highly differentiated filiform papillae which have developed as a compensatory mechanism of mastication, since both animals are in effect, edentulous. In the light of these findings and observations on the tongue of both animals, it is suggested that a degree of parallel evolution of the palate (as part of the masticatory apparatus) has occurred.  相似文献   

6.
A case of multiple myeloma presenting as a plasmacytoma and mimicking a pituitary tumor is reported. The importance of recognizing the existence of plasmacytoma in the differential diagnosis of sellar and parasellar tumors is stressed, as it leads to important differences in management. The literature is reviewed. Patients presenting with plasmacytoma with symptoms of a pituitary adenoma have an average age of 58 years; the male to female ratio is 3:1; diplopia, headache, and progressive visual loss are the most important symptoms; third, sixth, and fourth cranial nerve palsies are the most common signs; and pituitary function is usually normal. CT scan of the sellar region is the imaging modality of choice; pathologically, light and electron microscopy are invaluable in making the correct diagnosis. Making the correct diagnosis allows further appropriate investigation for systemic disease and consequent management.  相似文献   

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A department of biomedical engineering can significantly enhance the impact of their research and training programs if a productive relationship with a medical school can be established. In order to develop such a relationship, significant hurdles must be overcome. This editorial summarizes some of the major challenges and opportunities for a department of biomedical engineering as they seek to build or enhance a relationship with a medical school. The ideas were formulated by engaging the collective wisdom from the Council of Chairs of the biomedical engineering departments.  相似文献   

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Characterisation of a potyvirus and a potexvirus from Chinese scallion   总被引:6,自引:0,他引:6  
Summary.  Molecular analyses of viruses infecting Chinese scallion (Allium chinense G. Don) showed that the plants did not contain any of the poty-, carla- or allexiviruses that are common in garlic plants in China. The complete sequences of a potyvirus and a potexvirus were determined and these were shown to represent different viruses from any in the databases. They could be transmitted mechanically to scallion but not to other Allium species (including garlic) or to Narcissus. The potyvirus, tentatively named Scallion mosaic virus, has a distant relationship (c. 62% nucleotide identity over the entire genome) to Turnip mosaic virus and Japanese yam mosaic virus, with which it grouped in phylogenetic analyses. Its genome is 9324 nts long, encoding a 341.3 kDa polyprotein of 3001 amino acids. The potexvirus, tentatively named Scallion virus X, has a genome 6987 nts long and its organisation was similar to that of the other potexviruses but with only 46.3–63.2% nucleotides identical to them. It is most closely related to Narcissus mosaic virus but phylogenetic analyses indicate that it should be considered a distinct species. Neither of the viruses have been detected in garlic, although the two host plants are closely related. Received September 28, 2001 Accepted December 20, 2001  相似文献   

12.
Mitochondrial ageing of a polar and a temperate mud clam   总被引:4,自引:0,他引:4  
We investigated mitochondrial ageing in a temperate (Mya arenaria) and an Antarctic (Laternula elliptica) mud clam, with similar lifestyle (benthic filter feeders) but different maximum life spans (MLSP), 13 and 36 years, respectively. The short-lived temperate M. arenaria showed a more pronounced decrease in mitochondrial function (respiration, respiratory control ratio, proton leak, membrane potential) with age than the long-lived Antarctic L. elliptica. H2O2 generation rates at habitat temperature were far higher in the short-lived M. arenaria compared to L. elliptica. Reactive oxygen species (ROS) production as proportion of the mitochondrial oxygen consumption rate (%H2O2/O2) increased significantly with age in M. arenaria, whereas in L. elliptica the proportion remained unchanged. Lower rates of mitochondrial H2O2 generation were presumably due to mild uncoupling as L. elliptica mitochondria showed higher proton leak compared to M. arenaria mitochondria. The results are discussed in to the light of the "Free Radical-Rate of Living theory", (Pearl, R., 1928. The Rate of Living. Alfred Knopf, New York; Harman, D., 1956. Aging: a theory based on free radical and radiation biology. J. Gerontol. 11, 298-300) and the "Uncoupling to Survive" hypothesis (Brand, M.D., 2000. Uncoupling to survive? The role of mitochondrial inefficiency in ageing. Exp. Gerontol. 35, 811-820).  相似文献   

13.
A weight control group is described, led jointly by a general practitioner and a clinical psychologist. Approaches employed included dietary advice, behavioural advice, and group support. Of the original 16 members (including one group leader), seven dropped out at an early stage and the reasons for this are discussed. All members were re-weighed at intervals up to 18 months after the beginning of the six-month intensive period. They were also interviewed by a psychological research worker a year after the start of the group. The results suggest that a combined dietetic and psychological approach to weight control is of value.  相似文献   

14.
Integration of Smad and MAPK pathways: a link and a linker revisited   总被引:6,自引:0,他引:6  
Massague J 《Genes & development》2003,17(24):2993-2997
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15.
A multicentre, controlled, randomised, open, comparative trial including 839 healthy adult volunteers was carried out in order to compare the immunogenicity and reactogenicity of two vaccines against hepatitis A virus (HAV) during primary immunization and after booster injection. The first vaccine was produced by Pasteur Mérieux (PM), and the second vaccine by Smith-Kline Beecham (SKB). The vaccination schedule consisted of 2 doses (months 0, 6) for PM and 3 doses (months 0, 1, and 6) for SKB. Two weeks after the first dose, the seroconversion rates among initially HAV seronegative subjects (n = 608) were 93.4% and 76.1% for the PM and SKB vaccines, respectively, the corresponding geometric mean titres (GMTs) were 59.0 mlU/ml versus 30.8 mlU/ml (modified RIA HAVAB assay, Abbott Laboratories). Two months after the beginning of immunization (one dose versus two doses) the GMTs were 138.4 and 161.6 mlU/ml, respectively. At month 7, the seroconversion rates were 100% for both vaccines, and the GMTs were 4, 189 and 3, 163 mlU/ml, respectively. After the first dose of vaccine, 24.6% and 19.6% of the PM and SKB vaccinees reported local reactions. The rates for systemic reactions were 27.2% and 25.0%, respectively. Lower rates for local and systemic reactions were seen after booster injections and statistical differences were not observed between the two vaccines. The study also demonstrated that vaccination was as well tolerated in subjects with anti-HAV antibodies as in HAV seronegative subjects. Logistic regression analysis revealed a significant vaccine effect on seroconversion rates only at week 2 (P<10?4). The same conclusions were drawn from the analysis of GMT by multivariate regression. When both times (week 2 and week 8) were analysed together, a statistically significant effect of interaction between time and vaccine was observed, indicating that the kinetics of antibody responses were different. © 1995 Wiley-Liss, Inc.  相似文献   

16.
The entrainment of circadian rhythms by light-dark (LD) cycles has been extensively investigated in laboratory studies. In almost all of these studies, organisms have not been allowed to modulate their exposure to the LD cycle. In the present study, the rhythm of running-wheel activity was investigated in nocturnal (domestic mice) and diurnal (Nile grass rats) rodents provided with light-tight nest boxes and maintained under long and short photoperiods. Photoperiod length had a significant effect on the duration of the daily active phase (alpha), on the phase angle of entrainment (psi), and on diurnality or nocturnality in both species. The availability of a nest box had a modest effect only on the variability of activity onsets. Neither in the nocturnal nor in the diurnal species was there any evidence of entrainment by frequency demultiplication or of entrainment without photic stimulation at either dawn or dusk. These results indicate that at least in the species studied, the ability of rodents to modulate their exposure to the LD cycle does not have a major effect on photic entrainment.  相似文献   

17.
A solitary skin lesion was found on the neck of a Weddell seal (Leptonychotes weddellii), chemically immobilized in Queen Maud Land (70 degrees 09'S, 05 degrees 22'E) Antarctica 2001. The lesion was elevated and 3cm in diameter, consisting of partly fresh and partly necrotic tissue, and proliferative papilloma-like structures were seen. Electron microscopy on a biopsy from the lesion revealed typical parapoxvirus particles. Polymerase chain reaction (PCR; B2L gene) generated amplicons of approximately 594 base pairs, comparable to Orf-virus, the prototype parapoxvirus. A comparison of these B2L PCR amplicon DNA sequences with corresponding sequences from other parapoxviruses, showed that the Weddell seal virus resembled isolates from grey seal (Halichoerus grypus) and harbour seal (Phoca vitulina) more than parapoxvirus from red deer (Cervus elaphus), sheep, cattle and Japanese serows (Capricornis crispus). It is thus concluded that the Weddell seal parapoxvirus belong to the tentative seal parapoxvirus species. Since parapox and orthopoxviruses may cause similar clinical diseases, we suggest that the term sealpox should be restricted to the clinical disease, whereas seal parapoxvirus should be used when caused by a parapoxvirus, rather than the general term "sealpox virus". This is the first verified case of parapoxvirus infection in a Weddell seal, and also the first report of any such infections in the Antarctic.  相似文献   

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A slow-growing mass in the left thigh of a 7-year-old spayed female fox terrier dog was originally diagnosed as an infiltrative lipoma by surgical biopsy. Necropsy findings one year later revealed multiple masses made up of well-differentiated adipocytes in the spleen, liver, lungs and a lymph node. The final histopathological diagnosis of these masses and, in retrospect, for the initial leg mass was well-differentiated liposarcoma. This case illustrates some of the confusion in current nomenclature of fatty tumours. Tumours made up of well-differentiated adipose cells which show no tendency toward invasion of surrounding tissue should be designated lipomas. We suggest that fatty tumours characterized by local tissue invasion and/or metastasis should be classified as liposarcomas. Liposarcomas may be further subdivided into well-differentiated and poorly-differentiated types.  相似文献   

20.
目的克隆槲寄生蛋白具有N-糖苷酶活性的毒性A链。方法利用硫酸铵沉淀、亲和色谱和离子交换色谱法,从吉林产槲寄生[Viscum coloratum(Komar.)Nakai]中提取、分离、纯化其中具有半乳糖结合活性的蛋白质成分。采用SDS-PAGE分析纯化的蛋白样品,蛋白条带转印至PVDF膜后,Edman降解法测定肽链的N端序列。由测序结果设计引物,利用RT-PCR方法克隆一种蛋白A链的基因。结果从槲寄生中纯化出两种高毒性的蛋白质新成分CM-1、CM-2,其中CM-1 A链被克隆并测序,其与白果槲寄生蛋白A链的同源性较高。结论一种新槲寄生蛋白A链的基因被成功克隆。  相似文献   

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