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151.
The effects of deprenyl on methamphetamine-induced dopamine depletions were studied in mice. Four SC injections of 12.5 mg/kg of methamphetamine at two-hour intervals caused substantial (72-82%) and long-lasting depletions of striatal dopamine. Pretreatment with either 25 or 40 mg/kg of deprenyl did not significantly alter the magnitude of this depletion. These results indicate that, unlike what is observed following MPTP, there is no protection afforded dopaminergic cells by deprenyl pretreatment in the methamphetamine model of parkinsonism. 相似文献
152.
J Zhang P Alfonso NR Thotakura J Su M Buergin D Parmelee AW Collins M Oelkuct S Gaffney S Gentz DP Radman GF Wagner R Gentz 《Canadian Metallurgical Quarterly》1998,12(3):390-398
Pustulosis palmoplantaris (PPP) is a common chronic skin disease, which is very resistant to treatment. It is not known why the lesions are located in the palms and soles. There are few studies of the disease and in particular studies of the histology. Fifty-nine patients with PPP answered a questionnaire concerning their medical history and 39 of them were clinically examined. Biopsy specimens were taken from involved skin in 22 of the 39 patients and studied immunohistologically for tryptase+ mast cells, EG2+ eosinophils, lipocalin+ neutrophils and CD3+ T lymphocytes. The sweat gland and sweat duct were visualized with AE1/AE3 antibody (cytokeratins 1-8, 10, 14/15, 16, 19). In addition to neutrophils in the pustule and lymphocytes in the upper dermis, there were also large numbers of mast cells and eosinophils in the subpustular area. Numerous eosinophils were present in the pustule. The epidermal part of the eccrine duct was not detectable in any of the specimens from patients with PPP but was present in all of the nine control persons (including two smokers). The results indicate that the acrosyringium is involved in the inflammation and also that mast cells and eosinophils participate in a hitherto unknown way. Of the 39 patients clinically examined, two had previously diagnosed thyroid disease and two had gluten hypersensitivity. Seventeen had one or several abnormal serum concentrations of thyroid-stimulating hormone, thyroxin, antibodies against thyroglobulin or thyroperoxidase and 10 had immunoglobulin (Ig) A antibodies to gliadin. The mean +/- SD for serum IgA and for eosinophil cationic protein was increased. From the questionnaire the most notable finding was that 56 of the 59 patients had been or still were smokers, all of whom had started smoking before the first signs of PPP. We hypothesize that the acrosyringium might be the target for the inflammation and that PPP is linked to autoimmune thyroid disease and smoking. 相似文献
153.
We combined histofluorescence with in situ hybridization to identify GABAergic neurons in the arcuate nucleus (ARC) following electrophysiological recordings, using GAD65 as a marker. Intracellular recordings were made in hypothalamic slices prepared from ovariectomized guinea pigs. Over 90% of ARC neurons tested with the GABA(B) receptor agonist baclofen responded with a membrane hyperpolarization or an outward current. The hyperpolarization was dose-dependent, and the GABA(B) receptor antagonist CGP 35,348 produced a rightward shift in the agonist dose-response curve. Agonist potency was lower, and the efficacy greater, in GAD-positive neurons. The use of this novel technique for identifying GABAergic neurons thus reveals differences in the pharmacodynamics of GABA(B) receptor activation GABAergic and non-GABAergic ARC neurons. 相似文献
154.
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156.
EK Outwater BJ Wagner C Mannion JK McLarney B Kim 《Canadian Metallurgical Quarterly》1998,18(6):1523-1546
Gonadal cell types that derive from the coelomic epithelium (sex cords) or mesenchymal cells of the embryonic gonads include granulosa cells, theca cells, fibroblasts, Leydig cells, and Sertoli cells. Ovarian tumors of these cell types are called sex cord-stromal tumors. This group of tumors represents approximately 8% of ovarian neoplasms and affects all age groups. The more common types are granulosa cell tumors (GCTs), fibrothecomas, and Sertoli-Leydig cell tumors. Sex cord-stromal tumors are of interest partly because of their hormonal effects, which are rare for other ovarian neoplasms. These effects include estrogenic effects (pseudoprecocious puberty, endometrial bleeding, endometrial hyperplasia and carcinoma) and virilization. The variety of gross appearances of these tumors, ranging from large multicystic masses to small solid masses, would appear to preclude a specific radiologic diagnosis. However, in many patients, both clinical and radiologic clues can suggest the diagnosis, including predominantly fibrous content at ultrasound or magnetic resonance imaging (fibrothecoma), large hemorrhagic multicystic mass in a child with pseudoprecocious puberty (juvenile GCT), and associated syndromes such as Peutz-Jeghers syndrome (sex cord tumor with annular tubules) or Ollier disease and Maffucci syndrome (juvenile GCT). 相似文献
157.
The surface growth kinetics of CdTe and HgTe have been investigated during molecular and metalorganic molecular beam epitaxy.
The surface growth kinetics was studied through in-situ measurements of the growth rate as a function of flux ratio and substrate
temperature on the (001), (111)B, and (211)B CdTe surface orientations. For the (001) and (111)B CdTe growth kinetics, the
existence of low binding energy surface precursor sites was proposed for both molecular and atomic growth species before lattice
incorporation. Intensity oscillations were observed during HgTe growth on misoriented (111)B surfaces and during CdTe growth
on the (211)B orientation. The (211)B surface reconstructions displayed both vicinal and singular surface characteristics,
depending on the growth flux ratio. 相似文献
158.
We describe the outcome of various combinations of choices made by individuals in the solution of a non-trivial combinatorial problem on a computer. The programs which result are analyzed with respect to execution speed, design time, and difficulty in debugging. The solutions obtained vary dramatically as a result of choices made in the overall design of the solution. Choices made at lower levels in the top-down tree of design choices seem to have less effect on the parameters analyzed. A tradeoff between mathematical effort in algorithm design, and program speed is evident, since some solutions required solution-time which grows exponentially with the case size, while another solution presented here gives a closed-form expression for the required answers for all large cases. 相似文献
159.
Pooled IgG preparations for i.v. use (IVIg) have been shown to possess anticomplementary activity in autoimmune and systemic inflammatory diseases. Both in vitro and in vivo, IVIg is a preferential acceptor of activated C4 and C3, thus diverting complement activation from the target surface. We explored the effect of IVIg on complement-bacteria interactions in an attempt both to determine the safety of IVIg preparations in relation to natural immunity to bacteria and to extend our knowledge of the physiologic mechanism of action of IVIg. Using both complement-sensitive and complement-resistant bacterial strains, we investigated the effect of IVIg on C3 binding to bacterial surfaces. In all cases, whether complement could be directly activated by bacteria through the classical or the alternative pathway, IVIg had no effect on the amount of C3 bound to bacteria. In addition, IVIg did not inhibit complement-dependent bacterial lysis. Interestingly, increasing concentrations of IVIg induced an increase in C1q binding, suggesting the presence of low affinity complement-fixing antibacterial Abs in certain preparations. Using serum samples from patients treated with IVIg, complement binding to and lysis of complement-sensitive bacterial strains were not modified as compared with normal controls and pretreatment samples, although a decrease in C3 binding to sensitized human erythrocytes was observed. Our data suggest that IVIg does not affect direct complement-bacteria interactions, although it is a potent agent to use for diversion of complement activation on sensitized target surfaces. 相似文献
160.
A 50-year-old woman ASA 2 underwent carbon dioxide hysteroscopy under general anaesthesia. Monitoring showed a sudden and rapid fall in end-tidal carbon dioxide followed by oxygen desaturation. She became pulseless and cyanosed. Resuscitation with oxygen, intravenous adrenaline and head-down tilt restored her to haemodynamic stability. Hyperbaric therapy was also administered as air embolism could not be excluded. 相似文献