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1.
In neonatal rat gonadotrophs, melatonin inhibits several GnRH-induced effects: stimulation of LH release as well as the increase of several second messengers as cAMP, diacylglycerol and [ Ca2+ ]i . Recently, GnRH has been shown to induce expression of immediate early genes of fos and jun family in adult rat gonadotrophs. The purpose of this study was to determine, whether melatonin inhibits the GnRH-induced induction of cFos in neonatal rat pituitary cells. 相似文献
2.
Anne F. Mannion Barbara R. Weber Jiri Dvorak Dieter Grob Markus Müntener 《Journal of orthopaedic research》1997,15(6):881-887
A knowledge of the alteration in the fibre type profile of paraspinal muscle associated with low back pain is essential for the design of successful rehabilitation programmes. In attempting to compare the muscles of patients with low back pain with those of controls, few previous studies have considered factors such as gender, age, and size of the subjects, each of which can potentially confound interpretation of the results. We obtained samples of lumbar paraspinal muscle during spinal surgery from 21 patients with low back pain and, using the percutaneous biopsy technique, from 21 control volunteers matched for gender, age, and body mass. The samples were subject to routine histochemicsl typcal analysis to determine characteristics of muscle fibre type. Compared with controls, the muscle of the patients had a significantly higher proportion of type-IIB (fast-twitch glycolytic) fibres than type- I (slow oxidatve) fibres. The mean size of a given fibre type did not differ between the patients and the controls. Consequently, the relative area of the muscle iccupied by type-IIB fibres was higher and that by type-I fibres Was lower in the patients. The patients had a greater number of muscle samples with more than 1% type-IIC fibres, and abnormalities that could be described as pathological were more marked in the patients than in the controls. In conclusion, the paraspinal muscles of patients who have low back pain display a more glycolytic (faster) profile; this can be expected to render them less resistant to fatigue. 相似文献
3.
Herbert Oelschlger Jiri Volke Michael Berthold Vetter Petra Nikolajewski 《Archiv der Pharmazie》1990,323(7):411-415
Loprazolam (1) is a tricyclic benzodiazepine containing a new butazadiene moiety, which has not been investigated by polarography up to now. 1 is reduced in three waves at a DME over the whole pH-region. In BRP (pH 2-9) 10 electrons are consumed in this process. The first step is suitable for the determination of 1 in Loprazolam tablets containing 1 or 2 mg. These tablets are on the pharmaceutical market in several European countries. The mechanism of the electrode process will be reported in the communication XXXIV. 相似文献
4.
5.
Lonský V Mand'ák J Kubícek J Volt M Procházka E Dominik J 《Acta medica (Hradec Králové) / Universitas Carolina, Facultas Medica Hradec Králové》2005,48(2):95-98
The very large patient (weight 142 kg, height 197 cm, body surface 2.76 m2) was referred to acute operation with dissecting type A ascending aortic aneurysm. The calculated blood flow was 6.63 l/min. To anticipate potential difficulties with perfusion and oxygenation two oxygenators connected in parallel were incorporated into the circuit. Bentall procedure with ACB to the RCA was performed. The perfusion was uneventful. Bypass time was 259 minutes, cross clamp time 141 minutes, circulatory arrest 7 minutes. The highest oxygenators gas flow was 2.6 l/min with maximum FiO2 0.42. The use of two in parallel connected oxygenators is a very effective, easy and safe method in such extreme perfusions, offering to the perfusionist a great reserve of oxygenator output. 相似文献
6.
Bartkova J Rajpert-De Meyts E Skakkebaek NE Lukas J Bartek J 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(1):252-266
Deregulated cell cycle and defective genome-integrity checkpoints are among the hallmarks of cancer.Here we summarize our recent studies of key components of the GI/S machinery in normal human spermatogenesis, and their abnormalities in testicular germ cell tumours (TGCTs), with special emphasis on carcinoma in situ lesions (CIS). Our combined immunohistochemical and immunoblotting analyses of normal human adult and fetal testes, CIS, seminomas, embryonal carcinomas, and teratomas, revealed an 'unorthodox' spectrum of defects within the so-called RB pathway in TGCTs. The early aberrations included lack of expression of the retinoblastoma tumour suppressor (pRB) and the CDK inhibitor pl9ink4d, and overexpression of cyclin D2. Progression from CIS to invasive TGCTswas associated with loss of another two CDK inhibitors and tumour suppressors: pl6ink4a and pl8ink4c. We also found the lack of pRB and pl9ink4d in fetal gonocytes, the candidate target cell for all types of TGCTs. These findings, together with the status of the Chk2-p53 DNA-integrity checkpoint, are considered in relation to the origin, biology and pathogenesis of TGCTs, and potential implications of the GI/S defects for the curability of these tumours. 相似文献
7.
The changes of spatial EEG synchronisation during brisk and slow voluntary self-paced movements of the right and left index finger were analysed in 12 right-handed and 11 left-handed subjects. EEG was recorded from the left and right sensorimotor area using 24 closely spaced electrodes. A novel measure of spatial EEG synchronisation, -complexity, was computed separately for the left and right sensorimotor area in 64 overlapping one-second epochs representing 4.5 s of the pre-movement and 3.5 s of the post-movement period. -complexity was higher, hence spatial synchronisation was lower, in slow than in brisk movements, especially in the right-handed. A sustained increase of -complexity was observed during execution of a slow movement. A decrease of -complexity which was often associated with a brief burst of spatially synchronised 10-Hz oscillations occurred at the onset of extensor muscle contraction. We suggest that increased spatial EEG synchronisation at movement onset may prevent spillover of excitation from the sensorimotor hand area to other cortical regions. During movement, the cortical neuronal assemblies subserve distinct, specialised functions manifesting in increased -complexity. 相似文献
8.
Harold Z. Hirsch Andrej Tarkowski William J. Koopman Jiri Mestecky 《Journal of clinical immunology》1989,9(4):273-278
The enzyme-linked immunospot assay was used to enumerate both the number and the frequency of spontaneous IgG, IgA, and IgM immunoglobulin-secreting cells and IgA- and IgM-rheumatoid factor (RF)-producing cells present in the gingivae and peripheral blood of adult periodontitis patients. Cells from 29 patients were incubated on plates coated with human IgG, Fc, or F(ab)2 fragments and on plates coated with class-specific antihuman antibodies and secreted antibodies were subsequently visualized by means of an immunoenzymatic procedure. The data indicate that (1) IgA-RF- and IgM-RF-secreting cells are frequently present in the gingiva of adult periodontitis patients; (2) production of RF in gingivae of adult periodontitis patients occurs in the absence of demonstrable RF production by simultaneously obtained peripheral blood mononuclear cells, suggesting that local autoimmune reactions may occur in this disease; and (3) lack of correlation between IgA-RF and IgM-RF production in diseased gingiva suggests that the two RF isotypes are regulated independently of each other. 相似文献
9.
Neuropeptide Y in the female reproductive tract of the rat. Distribution of nerve fibres and motor effects 总被引:2,自引:0,他引:2
The spontaneous firing of single neurones in the region of the lateral reticular nucleus was the subject of a pharmacological study employing microiontophoretic and systemic application of adrenoceptor agonists and antagonists. Both iontophoretic noradrenaline and systemic clonidine depressed neuronal firing. The depressions were consistently reversed by the alpha-2 antagonist RX781094. Other adrenergic antagonists, prazosin and sotalol, were ineffective. The results suggest the existence of alpha-2 receptors in this region of the brain. 相似文献
10.
CD19 is an important pan B cell marker and co-stimulatory protein in humans and mice. Efforts to further characterize B cell ontogeny in swine have been hampered by the lack of monoclonal antibodies (mAb) to valuable surface markers like Vpre-B, CD19, CD34 and CD43. We report here on the complete nucleotide and deduced amino acid sequence of porcine CD19, the cross-reactivity of anti-human CD19 monoclonals and efforts to prepare anti-porcine CD19 mAb to bacterially-expressed products. Porcine CD19 is highly homologous to those in the few other species studied, i.e. human, mouse and guinea pig, but only in certain domains. Among the 14 CD19 exons, homology approaches 90% to human CD19 in exons 6, 9, 11 and 12 and is approximately 80% with other species in this region. The highly homologous C-terminal cytoplasmic region contains nine tyrosines including the YEND/E motif that binds the SH2 domain of Fyn. Two different porcine CD19 isoforms that differ in their 3' UTRs were identified just as in human CD19. Thus, the signaling properties of CD19 may be similar to those in humans. On the other hand, only 60% sequence similarity was seen in exons 1-5 that encode the N-terminal extracellullar region that is involved in ligand binding and is the target of CD19-specific mAb. This probably explains why only 1 of the 17 anti-human CD19 mAb tested recognized swine B cells. Furthermore, when the extracellular domains of CD19 were expressed in E. coli, mAbs to the bacterially-expressed product did not recognize CD19 on porcine B cells suggesting that carbohydrate-dependent conformation may determine antigenicity. 相似文献