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71.
Upregulated expression of the low-affinity neurotrophin receptor (p75) in the central nervous system (CNS) during experimental autoimmune encephalomyelitis (EAE) has recently been demonstrated. To investigate whether p75 plays a role in disease pathogenesis, we adopted a gene therapy approach, utilizing antisense oligonucleotides to downregulate p75 expression during EAE. Phosphorothioate antisense oligonucleotides (AS), nonsense oligonucleotides (NS) or phosphate buffered saline (PBS) were injected daily for 18 days after immunization of SJL/J (H-2s)-mice with myelin proteolipid protein (PLP) peptide 139-151. In the AS group, there was a statistically significant reduction in both the mean maximal disease score (1.85 in the AS, 2.94 in the NS and 2.75 in the PBS-groups, respectively, P < 0.025) and in the cumulative disease incidence ( approximately 60% in the AS group and approximately 90% in the control groups). Histological and immunohistochemical analysis showed reduced inflammation and demyelination, as well as reduced p75 expression at the blood-brain barrier (BBB) in the AS-treated mice in comparison with both control groups. There was no difference, however, in p75 expression on neural cells within the CNS between the three groups of mice. We conclude that p75 could play a proactive role in the pathogenesis of EAE and may exert its effect at the level of the BBB.  相似文献   
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1-(m-chlorophenyl)-biguanide, a potent high affinity 5-HT3 receptor agonist   总被引:4,自引:0,他引:4  
1-(m-Chlorophenyl)-biguanide (mCPBG) was examined and compared with three 5-HT3 receptor agonists in three 5-HT3 receptor models. mCPBG inhibited [3H]GR67330 binding to 5-HT3 receptors with high affinity (IC50 1.5 nM). mCPBG depolarized the rat vagus nerve with an EC50 one tenth of that for 5-HT (0.05 vs. 0.46 microM); the maximum depolarization was approximately half that for 5-HT. The mCPBG depolarization was potently blocked by the selective 5-HT3 antagonist, ondansetron (pKB 8.6 +/- 0.1). In anaesthetised cats, mCPBG potently evoked the Bezold-Jarisch reflex which was blocked by low doses of ondansetron (10 micrograms/kg i.v.). It is concluded that mCPBG is a potent, high affinity 5-HT3 receptor agonist.  相似文献   
75.
Changing management of gallstone disease during pregnancy   总被引:7,自引:4,他引:3  
Background: Symptomatic gallstones may be problematic during pregnancy. The advisability of laparoscopic cholecystectomy (LC) is uncertain. The objective of this study is to define the natural history of gallstone disease during pregnancy and evaluate the safety of LC during pregnancy. Methods: Review of medical records of all pregnant patients with gallstone disease at the University of California, San Francisco, from 1980 to 1996. Results: Of approximately 29,750 deliveries, 47 (0.16%) patients were treated for gallstone disease, including biliary colic in 33, acute cholecystitis in 12, and pancreatitis in two. Conservative treatment was attempted in all patients but failed in 17 (36%) cases. Two patients required combined preterm Cesarean-section cholecystectomy and 10 required surgery in the early postpartum period for persistent symptoms. Seventeen patients required cholecystectomy during pregnancy for biliary colic (10), acute cholecystitis (six), and pancreatitis (one). Three patients were treated with open cholecystectomy. Fourteen patients underwent LC at a mean gestational age of 18.6 weeks, mean OR time of 74 min, and mean length of stay of 1.2 days. Hasson cannulation was utilized in 11 patients. Reduced-pressure pneumoperitoneum (6–10 mmHg) was used in seven patients. Prophylactic tocolytics were used in seven patients, with transient postoperative preterm labor observed in one. There were no open conversions, preterm deliveries, fetal loss, teratogenicity, or maternal morbidity. Conclusions: In past years, symptomatic gallstones during pregnancy were managed conservatively or with open cholecystectomy. LC is a feasible and safe method for treating severely symptomatic patients. Received: 3 April 1997/Accepted: 5 July 1997  相似文献   
76.
Administration of haloperidol (1.4–1.6 mg/kg/day) for up to 12 months or sulpiride (102–109 mg/kg/day) for between 6 and 12 months increased the frequency of purposeless chewing jaw movements in rats. N,n-propylnorapomorphine (NPA) (0.25–2.0 mg/kg SC) did not induce hypoactivity in haloperidol-treated rats at any time; sulpiride treatment for 9 and 12 months caused a reduction in the ability of NPA to induce hypoactivity. Haloperidol, but not sulpiride, treatment enduringly inhibited low dose apomorphine effects (0.125 mg/kg SC). After 12 months, sterotypy induced by high doses of apomorphine (0.5–1.0 mg/kg) was exaggerated in haloperidol-, but not sulpiride-treated rats.Bmax for specific striatal 3H-spiperone binding was increased by haloperidol, but not sulpiride, treatment throughout the study. Bmax for 3H-NPA binding was elevated only after 12 months of both haloperidol and sulpiride treatment. Bmax for 3H-piflutixol binding was not alfered by chronic haloperidol or sulpiride treatment. Striatal dopamine-stimulated adenylate cyclase activity was inhibited for the 1st month of haloperidol treatment, thereafter returning to control levels; dopamine stimulation was increased after 12 months of sulpiride treatment. Striatal acetylcholine content was increased after 3 and 12 months of treatment with haloperidol, but was not affected by sulpiride.Chronic administration of sulpiride does not induce identical changes in striatal dopamine function to those caused by haloperidol.  相似文献   
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The radiology of ischemic proctitis   总被引:2,自引:0,他引:2  
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79.
A method for the rapid and reproducible recording of 24 chest electrode potentials is described. Rigid electrodes are equally spaced around the thorax in three rows of eight. The electrodes move radially and are spring loaded so as to maintain contact with the skin regardless of the shape of the subject's torso. The inclusion of an impedance convertor in the electrode assembly removes the necessity for using electrode cream. Although equal spacing of the electrodes around the thorax is inefficient in terms of information content per electrode the attention to detail required for electrode placement using the described system is minimised as compared with other multiple lead systems. Furthermore, the principles adopted in the design and construction of the apparatus do not limit the number of chest electrodes to 24.  相似文献   
80.
West Nile virus risk assessment and the bridge vector paradigm   总被引:6,自引:0,他引:6  
In the northeast United States, control of West Nile virus (WNV) vectors has been unfocused because of a lack of accurate knowledge about the roles different mosquitoes play in WNV transmission. We analyzed the risk posed by 10 species of mosquitoes for transmitting WNV to humans by using a novel risk-assessment measure that combines information on the abundance, infection prevalence, vector competence, and biting behavior of vectors. This analysis suggests that 2 species (Culex pipiens L. and Cx. restuans Theobald [Diptera: Cilicidae]) not previously considered important in transmitting WNV to humans may be responsible for up to 80% of human WNV infections in this region. This finding suggests that control efforts should be focused on these species which may reduce effects on nontarget wetland organisms. Our risk measure has broad applicability to other regions and diseases and can be adapted for use as a predictive tool of future human WNV infections.  相似文献   
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