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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
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Thirty-four patients with atlanto-axial instability due to rheumatoid arthritis were examined with plain x-ray views and functional magnetic resonance imaging (MR), and were neurologically evaluated. Transcranial brain stimulation was performed in 25 patients. In 22 cases, the authors observed inflammatory tissue thicker than 3 mm behind the odontoid peg. The spinal canal diameter was significantly decreased in the flexed position. Nine patients showed signs of cranial migration of the axis. The diameter of the spinal cord was measured to be 7.4 mm in the neutral position, and 6.5 mm in flexion. The difference between the diameter of the neutral and flexed positions was highly significant. Twelve of the 34 patients displayed clinical signs of cervical myelopathy, and 13 showed a significant delay of central motor latency, as calculated from the motor evoked potentials. Surgical intervention, either by a posterior approach only or combined with a transoral dens and inflammatory tissue resection, is recommended in patients with progressive atlanto-axial instability, pathologic clinical and neurophysiologic findings, and a spinal cord diameter of less than 6 mm in flexion. Severe pain and cranial migration of the axis, as measured by the MRI, also justify a surgical intervention. 相似文献
4.
Nine healthy adults and 43 patients with cervical spine injury were examined by using functional (computerized tomography) CT scanning. The ranges of axial rotation at the levels occiput C0-C1, C1-C2, and C2-C3 were measured. A rotation at C0-C1 greater than 8 degrees; at C1-C2, 56 degrees; or a right-left difference C0-C1 greater than 5 degrees and C1-2 greater than 8 degrees indicates hypermobility. A rotation at segment C1-C2 of less than 28 degrees indicates hypomobility. Surgical stabilization of rotatory instability could be considered as a possible therapeutic procedure. 相似文献
5.
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
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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
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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
10.
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