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81.
HJ Rupprecht H Darius U Borkowski T Voigtl?nder B Nowak S Genth J Meyer 《Canadian Metallurgical Quarterly》1998,97(11):1046-1052
OBJECTIVE: To explore the basis of the gender-based differences in endocrine and surgical findings in patients with prolactinoma (prolactin cell adenoma) as well as in their clinical outcome. MATERIAL AND METHODS: In young or reproductive-age female patients, older women (beyond 40 years of age), and male patients, we systematically studied the following factors: operative and endocrine features (tumor size, invasiveness, preoperative serum prolactin level, and biochemical outcome), specific biologic variables (mitotic index, MIB-1 labeling index, and p27 immunoreactivity), and hormone receptor status (estrogen and progesterone receptor proteins as well as dopamine D2 receptor messenger RNA). RESULTS: Of the various factors assessed, the preoperative prolactin level and MIB-1 labeling index were lower in young female patients in comparison with older female and particularly male patients. Hormone levels were also positively associated with mitotic activity as well as the MIB-1 labeling index. Although invasion was infrequent in microadenomas of young female patients, no statistically significant differences in tumor size or invasiveness were noted among the three patient groups. Absence of differences in invasiveness may, in part, be explained by artifacts of case selection. CONCLUSION: The basis for the observed differences in proliferative activities in tumors of the three study groups is not readily apparent but may reflect differences in the endocrine milieu or the effect of sex steroid hormone receptors, tumoral vascularity, or specific growth factors. 相似文献
82.
P Helmbold B Hegemann HJ Holzhausen T Klapperstück WC Marsch 《Canadian Metallurgical Quarterly》1998,134(10):1275-1278
BACKGROUND: The purpose of this study was to test the disease-controlling effect of low-dose oral etoposide monotherapy in adult-onset multisystem Langerhans cell histiocytosis. There are no previous reports of low-dose etoposide monotherapy for this condition. OBSERVATIONS: A 27-year-old man with a 7-year history of multifocal chronic Langerhans cell histiocytosis presented with severe disabling ulcers in intertriginous areas. He had previously been treated with 2 different regimens of antitumoral chemotherapy; one had to be discontinued due to myelosuppression and the other had proved ineffective. We treated with oral etoposide monotherapy at 50 mg/d (22 mg/m2 per day) for 21 days. The treatment was repeated at 28-day intervals for a total of 6 cycles. A rapid initial response with subtotal diminution of the involved skin area was found. No adverse effects were observed. The clinical picture has remained stable during the 7 months following cessation of therapy. CONCLUSION: Low-dose oral etoposide treatment is an adequate therapeutic measure for prolonged disease control in adult-type Langerhans cell histiocytosis. 相似文献
83.
The binding of the calcium-regulatory protein calmodulin (CaM) to caldesmon (CaD) contributes to the regulation of smooth muscle contraction. Two regions of caldesmon have been identified as putative calmodulin-binding domains. We have earlier reported on the binding of one of these domains to calmodulin (Zhang & Vogel (1994) Biochemistry 33, 1163-1171). Here we have studied the binding of CaM to synthetic peptides of CaD which contain: (1) both the first and second CaM-binding domains; (2) the second CaM-binding domain; and (3) the sequence between the first and second CaM-binding domains. Two-dimensional transferred nuclear Overhauser enhancement proton NMR measurements as well as circular dichroism studies of a 22-residue peptide NKETAGLKVGVSSRINEWLTK, which contains the second CaM-binding domain, show that only the C-terminal half of the peptide becomes alpha-helical upon binding to CaM. Somewhat surprisingly, the shorter 9-residue peptide SRINEWLTK was sufficient to form a 1:1 complex with CaM; this peptide appears to bind as a 3(10)-helix. Proton-carbon-13 correlation NMR titration studies with specifically labeled [methyl-13C]methionine CaM were used to study the participation of the hydrophobic regions in both domains of the dumbbell shaped CaM in peptide binding. Binding of a 54-residue CaD peptide containing both CaM-binding domains affects all the 8 Met residues in the two hydrophobic domains of CaM (only Met 76 in the linker region of CaM is not involved), while binding of the second CaM-binding domain of CaD influences principally Met 51, 71, and Met 124, 144. Simultaneous binding to CaM of two peptides comprising the first and the second CaM-binding domains also caused changes to all Met residues except Met 76. Taken together, these data demonstrate that both CaM-binding domains of CaD can bind simultaneously to the two hydrophobic regions of CaM. 相似文献
84.
The presented adsorption--process KOMBISORBON is applied for high efficient off-gas purification, preferably of polychlorinated dioxins and furans from off-gas of incineration plants, which are generated, when these are operated under unfavourable conditions [2]. This off-gas purification process complies with german laws, which limit the concentration of these substances to less than 0.1 ng toxicity equivalents (TE) per cubic metre of gas [1]. The adsorbent, the adsorption process and its plant concept (fixed bed) is described in detail including economics and obtained operation results. Alternative removal technologies are briefly outlined. 相似文献
85.
H Grunze RW Greene HJ M?ller T Meyer J Walden 《Canadian Metallurgical Quarterly》1998,791(1-2):330-334
Actions of the new antiepileptic drug lamotrigine were characterised using whole cell patch clamp recordings from rat CA1 pyramidal cells in vitro. The results suggest that lamotrigine, besides its previously described effect on the fast sodium inward current and calcium currents, modulates the transient potassium outward current ID. This may be an effective mechanism to inhibit pathological excitation. 相似文献
86.
The goal of work was to investigate the electrogenic transport of Na ions by Na+,K(+)-ATPase in membrane fragments absorbed on a planar bilayer lipid membrane. The photorelease of ATP from an inactive precursor, caged ATP, induced a transient current and changes in the net system capacitance measured during the application of an alternating voltage. The increments of capacitance (delta c) decreased with the increase in the frequency of the applied voltage. The characteristic frequency F0 of the steepest slope of the curve significantly decreased in solutions with high ionic strength (either NaCl or choline chloride), in which Na+ transport is decelerated. The value of delta c correlated with the total charge delta q transported across the membrane. The capacitance increments decreased when the Na+ concentration in solution decreased. At a concentration below 2 mM the increment became negative. The increase in membrane capacitance can be attributed to the charge relaxation process inside the protein, as discovered in the cells by other methods. The characteristic frequency F0 depends on the time constants of charge redistribution. The nonlinear dependences of delta c on delta q were explained by a voltage bias across the membrane fragments resulting from pumping. The potentials corresponding to the maximum capacitance change were similar to the midpoint potentials of the equilibrium charge distribution and depended on the Na+ concentrations in solution. The model enabled also the determination of the total capacitance of the active region of a lipid membrane with the adsorbed protein containing membrane fragments. 相似文献
87.
STUDY DESIGN: Retrospective analysis of 31 cases of cervical spondylotic myelopathy treated by four-level subaxial cervical corpectomy. OBJECTIVE: To determine whether extremes of anterior decompression and fusion have inordinate or unique levels of morbidity. SUMMARY OF BACKGROUND DATA: There is a paucity of data on experience with four-level corpectomy. However, counsel against such surgery can be found. MATERIALS AND METHODS: The records and studies of 31 consecutive cases of cervical spondylotic myelopathy, treated by four-level corpectomy, were retrospectively analyzed. Patients in 26 cases were observed longer than 2 years. No hardware was used in the procedures. External orthosis, worn for 6 months, was a Philadelphia-type collar in 25 patients and a halo vest in 6. RESULTS: Three patients died within 3 weeks of surgery (9.7%). Delayed radiculopathy occurred in four patients after surgery, three had acute graft complications, and one had pseudomeningocele, for a morbidity rate of 25.8%. There was no infection or worsened myelopathy. CONCLUSIONS: No unique morbidity is associated with extremes of subaxial decompression when compared with surgery of lesser extent. 相似文献
88.
HJ Cho JK Kim HC Park JK Kim DS Kim SO Ha HS Hong 《Canadian Metallurgical Quarterly》1998,154(1):224-230
In the present study, we evaluated changes in brain-derived neurotrophic factor (BDNF) immunoreactivity in the rat lumbar (L) 5 dorsal root ganglion (DRG) and areas where afferents from the DRG terminate, the L5 spinal cord and gracile nuclei, following unilateral sciatic nerve transection or crush. From 3 days to 4 weeks following cut or crush injury, the percentage of medium and large BDNF-immunoreactive neurons in the ipsilateral DRG increased significantly compared with those on the contralateral side. Following cut injury, there was no significant change in the percentage of small BDNF-immunoreactive neurons in the ipsilateral DRG; however, the intensity of immunoreactivity of these cells decreased. Following crush injury, however, both the percentage and intensity of small BDNF-immunoreactive neurons in the ipsilateral DRG significantly increased. Following cut injury, the expression of BDNF-immunoreactive axonal fibers decreased markedly in the ipsilateral superficial laminae of the L5 spinal cord and increased significantly in the ipsilateral deeper laminae of the spinal cord and gracile nuclei. Crush injury induced a marked increase in the expression of BDNF-immunoreactive axonal fibers in the superficial laminae of the spinal cord and gracile nuclei. These differences in BDNF response in the DRG and spinal cord after cut or crush injuries may reflect differences in trophic support to the injured DRG neurons and altered neuronal activity in the spinal cord and gracile nuclei following different types of peripheral nerve injury. 相似文献
89.
Benign solitary fibrous tumour, a rare mesenchymal tumour of adults, usually arises from the pleura. Only a few cases have been reported in the retroperitoneum and, to our knowledge, there has been no report of its imaging features. We describe the MRI features of benign solitary fibrous tumour arising from the pre-sacral space. 相似文献
90.
We investigated the contact guidance phenomenon of rat dermal fibroblasts (RDF) on microgrooved polystyrene substrates. Grooves were 1 microm deep, and between 1 and 10 microm wide. Light microscopy and digital image analysis (DIA) showed that RDF were oriented on all microgrooved substrates. Scanning electron microscopy showed that RDF cultured on 1 or 2 microm wide grooves were positioned on top of the ridges. On the wider 5 and 10 microm grooves, the cells were able to descend into the grooves. In confocal laser scanning microscopy, focal adhesions were lying in the same direction as the actin filament where they attached to. DIA confirmed an orientational behavior of focal adhesions and actin filaments on microgrooves. There were no differences in the measured orientation between the different grooves. Besides, no obvious preference was found for focal adhesions to lie along edges of the surface ridges. Transmission electron microscopy showed that focal adhesions were able to bend along the edges of ridges. On the basis of our observations, we suggest that the breakdown and formation of fibrous cellular components, especially in the filopodium, is influenced by the microgrooves. The microgrooves create a pattern of mechanical stress, which influences cell spreading and cause the cell to be aligned with surface microgrooves. 相似文献