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51.
Toxoplasma gondii encysts in skeletal muscle. Although only rarely found at muscle biopsy, this parasite has previously been regarded as a possible cause of polymyositis. We report a case of biopsy-proven toxoplasmic myositis in a non-HIV-infected patient that led to recognition of idiopathic CD4 lymphocytopenia (ICL), a rare condition typically associated with opportunistic infections. Interestingly, the CD25(+) subset that corresponds to the CD4(+) regulatory T cells controlling autoimmune processes was lacking. Steroid and antiprotozoal therapy led to recovery. 相似文献
52.
Getahun H Lambein F Van der Stuyft P 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2002,96(6):700-703
An exploratory study was conducted in the rural Estie district of Ethiopia in 1997 to identify the role of ABO blood group, rhesus factor, and type of grass pea (Lathyrus sativus) diet in the susceptibility to neurolathyrism. Five-hundred study subjects (250 cases and 250 controls) were examined and interviewed, and had their ABO and rhesus blood groups determined. The majority (86%) of the cases were males. Blood group O was the most common in the patients and controls followed by groups A, B, and AB. The vast majority of the study subjects were rhesus-positive. The gravy (Shiro) grass pea preparation was consumed by 91.6% of the study population, boiled (Nifiro) by 86%, and roasted (Kollo) by 56.4%. Almost half (48%) of the cases had consumed grass pea for > 4 months compared to 8% of controls (P < 0.001). There was a significant association between the risk for neurolathyrism and the consumption of boiled (adjusted odds ratio [AOR] = 98.4) and roasted (AOR = 55.62) forms of grass pea. There was no risk of paralysis associated with consumption of the gravy form of grass pea (AOR = 0.40, 95% confidence interval 0.1-2.0). Blood group O remained significantly associated with the disease after adjusting for age, type of grass pea preparation consumed, and duration of consumption (AOR = 2.90). 相似文献
53.
Gutman M Couillard S Roy J Labrie F Candas B Labrie C 《International journal of cancer. Journal international du cancer》2002,99(2):273-278
EM-652 exerts pure antiestrogenic activity in the mammary gland and endometrium, while tamoxifen, the antiestrogen most widely used for the treatment of breast cancer, exerts mixed antiestrogenic-estrogenic activity in these tissues. Our objective was to compare the agonistic and antagonistic effects of EM-652 with tamoxifen and 5 other antiestrogens on the growth of ZR-75-1 human breast xenografts in ovariectomized nude mice. During the 23 weeks of treatment at a daily oral dose of 50 microg, EM-652 was the only compound that decreased tumor size relative to pretreatment values, whereas the 6 other antiestrogens only decreased to various extents the progression rate stimulated by estrone. Under estrone stimulation, all groups of animals had more than 60% of their tumors in the progression category except for the EM-652-treated group, where only 7% of the tumors progressed. In the absence of estrone stimulation, progression was seen in 60%, 33%, 21% and 12% of tumors in the tamoxifen-, idoxifene-, toremifene- and raloxifene-treated groups, respectively, while only 4% of tumors progressed in the EM-652-treated group. The agonistic and antagonistic actions of each antiestrogen were also measured on endometrial epithelial cell thickness. Our present findings indicate that EM-652, in addition to being the most potent antiestrogen on human breast tumor growth, has no agonistic effect in breast and endometrial tissues. Since previous data have shown benefits of EM-652 on bone density and lipid profile, this compound could be an ideal candidate for chemoprevention of breast and uterine cancers, while protecting against osteoporosis and cardiovascular disease. 相似文献
54.
55.
Getahun H Lambein F Vanhoorne M Van der Stuyft P 《Tropical medicine & international health : TM & IH》2002,7(2):118-124
OBJECTIVES: To describe the neurolathyrism epidemic in Ethiopia and to identify associated household factors. METHODS: We interviewed 589 randomly selected heads of household in Debre Sina district of Ethiopia, the area afflicted by the recent neurolathyrism epidemic. Disease information was obtained for 2987 family members. RESULTS: Neurolathyrism patients were detected in 56 (9.5%) households (prevalence rate 2.38%). The mean number of affected family members per household was 1.27 (SD 0.65, range 1-3). Most (77.5%) patients developed the disability during the epidemic (1995-1999). The median age at onset of paralysis was 11 years with a range of 41 (range 3-44). Younger people were more affected during the epidemic than during the non-epidemic period (P=0.01). The presence of a neurolathyrism patient in the family was associated with illiteracy [adjusted OR (95% CI)=2.23 (1.07-5.10)] of the head of household, with owning a grass pea farm [adjusted OR (95% CI)=2.01 (1.04-3.88)] and with the exclusive cooking of grass pea foods using handmade traditional clay pots [adjusted OR (95% CI=2.06 (1.08-3.90)]. CONCLUSION: Males aged 10-14 years were most affected by neurolathyrism. Increased household risk was associated with illiteracy of the head of the household and exclusive cooking of grass pea foods with handmade traditional clay pots. 相似文献
56.
57.
The pharmacology of spontaneously active cholinoceptive neurones in the brain stem of rats anaesthetized with urethane has been investigated using microiontophoresis to administer muscarinic and nicotinic agonists and antagonists. 2. Acetylcholine (ACh) excited most cells but occasionally depressed their activity. Muscarine, and the muscarinic agonists methacholine and bethanechol produced prolonged excitation or inhibition of cells whereas nicotine produced prolonged excitations but no inhibitions. 3 Atropine selectively antagonized ACh excitations and both excitation and inhibition of neuronal activity produced by muscarine and muscarinic agonists, but not the excitations produced by nicotine, glutamate or DL-homocysteic acid. 4 Dihydro-beta-erythroidine (DHBE) and tubocurarine antagonized both ACh and nicotine excitations but not those induced by glutamate or DL-homocysteic acid. Inhibitions by ACh or muscarine were not affected. 5 It is concluded that excitations of cholinoceptive neurones in the rat brain stem may be mediated by activation of both muscarinic and nicotinic receptors whereas inhibitions are mediated by activation of a muscarinic receptor. 相似文献
58.
59.
Noradrenaline and prostaglandin E2 stimulate LH-RH release from rat median eminence through distinct 1-alpha-adrenergic and PGE2 receptors 总被引:2,自引:0,他引:2
Noradrenaline (NA) and prostaglandin (PG) E2 produced a dose-related stimulation of luteinizing hormone releasing hormone (LH-RH) release from incubated median eminence of adult male rats, with ED50 values of 6.10(-7) and 8.10(-8) M, respectively. The effects of some adrenoceptor agonists (10(-5) M) on LH-RH release were tested: only phenylephrine (alpha 1-agonist) stimulated LH-RH release; clonidine (alpha 2 greater than alpha 1-agonist) and isoproterenol (beta-agonist) were ineffective. Adrenoceptor antagonists (10(-6) M) were also tested: prazosin (alpha 1-antagonist) and phentolamine (alpha 1/alpha 2-antagonist) almost completely suppressed the enhanced release of LH-RH induced by NA. In contrast, neither yohimbine (alpha 2-antagonist) nor propranolol (beta-antagonist) altered this effect of NA. When tested alone, no significant effect was obtained on basal LH-RH release with any of the antagonists tested. Moreover, at concentrations that blocked the stimulation produced by NA, the adrenoceptor antagonists did not alter the effect of PGE2. Among seven PGs tested at 10(-6) M, only PGE2, PGE1, PGA2, and 16,16-dimethyl PGE2 significantly enhanced LH-RH secretion. 8-iso PGE2 weakly stimulated LH-RH secretion, whereas PGF2 alpha and PGD2 were ineffective. A direct correlation existed between the potency of these compounds to modify LH-RH secretion and to inhibit specific [3H]-PGE2 binding to hypothalamic membranes. In conclusion, these results suggest that the stimulation of LH-RH from median eminence induced by NA and PGE2 involves the activation of an alpha 1-adrenergic receptor and a PGE2 receptor, respectively. 相似文献
60.