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61.
Disseminated strongyloidiasis in AIDS: uncommon but important   总被引:5,自引:0,他引:5  
Disseminated Strongyloides stercoralis infection is a rare and severe but treatable complication of AIDS. We present a case where this infection was successfully treated and review the available literature. Cases may present many years after they have left an area endemic for Strongyloides infection, emphasizing the need for a full travel history. Symptoms are typically gastrointestinal and pulmonary, with infiltrates often seen on chest radiography. Diagnosis requires stool examination and biopsy of affected sites. Treatment with repeated courses of thiabendazole (25 mg/kg twice daily for 5 days) was successful in our case, but maintenance regimens have not yet been defined. The relative rarity of this complication of AIDS suggests that, where both infections are present, disseminated strongyloidiasis only arises either when HIV-induced immunodeficiency is profound or, possibly, when it is accompanied by impaired granulopoiesis.  相似文献   
62.
Four human monoclonal rheumatoid factors (MRF) were used to raise a panel of mouse monoclonal antibodies (mAb) which were selected in a solid-phase radioimmunoassay for binding to MRF but not normal IgM. Three mAb, each raised against a different MRF, bound to the majority of MRF and also to most polyclonal RF. Four other mAb bound selectively to the MRF against which they were raised and to no other MRF, and rarely to any polyclonal RF. Competition studies using cold and radiolabeled mAb further indicated that these mAb recognize distinct and different epitopes on MRF. RF activity of MRF was inhibited by 3 of the 4 mAb binding to a single MRF and 2 of the 3 mAb binding to multiple RF. It was thus concluded that of this panel of mAb 3 recognized cross-reactive idiotopes and the remainder demonstrated highly restricted idiotopes on MRF. These mAb identified MRF idiotopebearing cells in the peripheral blood of 3 of the MRF donors (and a further subject with type II essential cryoglobulinemia), with a frequency ranging from 0.3–10% of all mononuclear cells with the mAb to restricted idiotopes or 1.5–17% with mAb to cross-reactive idiotopes. These anti-idiotopic mAb should thus provide a highly specific means of identifying and monitoring MRF-producing cells in vivo.  相似文献   
63.
A new sensitive assay for pyrimidine nucleoside phosphorylase using non-radioactive substrates is described. With the natural substrate uridine (UR) and the analog, 5'-deoxy-5-fluorouridine (5'dFUR) conditions have been optimized to measure the product formation with reversed-phase high-performance liquid chromatography. Using automated injection large series of samples may be analyzed. The assay for UR phosphorylase appeared to be comparable to existing methods with radiolabeled UR as substrate regarding sensitivity and linearity. The assay has been used to measure kinetic parameters for 5'dFUR and UR in two cell lines from intestinal origin.  相似文献   
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Oral N-acetylcysteine supplementation in nine young healthy females induced a quick and highly significant decrease in plasma homocysteine levels and an increase in whole blood concentration of the antioxidant glutathione. N-acetylcysteine impresses as an efficient drug in lowering homocysteine concentration and might be beneficial for individuals with hyperhomocysteinemia who are at increased risk of cardiovascular disease.  相似文献   
66.
Mammographic evaluation of the postsurgical and irradiated breast   总被引:1,自引:0,他引:1  
Mammography is important in women who elect lumpectomy and radiation therapy for breast carcinoma: to record the preoperative state, to assess the completeness of resection, and to detect recurrences and second primaries. Mammography of these patients, however, is difficult since surgery and irradiation may cause changes simulating carcinoma. This article describes the findings in the postsurgical and irradiated breast and the difficulty of differentiating the changes from recurrent carcinoma. It also illustrates the findings in recurrences and second primaries.  相似文献   
67.
The lipophilic complex, 99Tcm-hexamethylpropyleneamine oxime (HMPAO) is an efficient leucocyte label, and labels granulocytes with more stability than mononuclear leucocytes. The recovery of 99Tcm-HMPAO granulocytes, expressed as the percentage of injected granulocyte-associated activity circulating as granulocyte-associated activity 40-45 min after injection, was 37% (S.E. 3%), similar to the recovery of 111In-labelled granulocytes isolated and labelled in plasma using tropolone. The T1/2 of 99Tcm-HMPAO labelled granulocytes in blood was 4.4 h (S.E. 0.4 h), less than that of 111In-labelled granulocytes, although when a correction was made for 99Tcm elution, it was 6.4 h. The initial biodistribution of 99Tcm-labelled leucocytes was similar to 111In-labelled granulocytes, with a rapid initial lung transit, prominent splenic activity, bone marrow activity and minimal hepatic activity, although, unlike 111In, 99Tcm activity was also seen in urine, occasionally in the gallbladder, and, from about 4 h, consistently in the colon. Bone marrow activity was particularly prominent with 99Tcm. About 6% of 99Tcm was excreted in the faeces up to 48 h after injection, and about 17% in urine up to 24 h. The time-activity curves of reticuloendothelial activity up to 24 h were broadly similar for the two labelled cell preparations, and the differences that were observed can be explained on the basis of a higher rate of 99Tcm elution. Clinical information given by the two agents was similar in 27 of 30 patients who received both. Of the three who gave different information, one received 111In-labelled granulocytes which were considered to be functionally suboptimal and two, with inflammatory bowel disease, showed different distributions of abnormal bowel activity. We conclude that with respect to granulocyte kinetics and clinical data, 99Tcm-HMPAO labelled leucocytes are comparable with 111In-tropolonate labelled granulocytes.  相似文献   
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The effect of the anti-ischemic compounds flunarizine and R 56865 on the veratridine-induced uptake of Ca2+ and Na+ was observed in cortical synaptosomes in the rat. The veratridine-induced uptake of Na+ and Ca2+ was determined by means of a measurement of synaptosomal oxygen consumption and a method for the uptake of 45Ca2+, respectively. Veratridine (10(-5) M) was found to induce a 3-fold increase in synaptosomal oxygen consumption (uptake of Na+) and uptake of 45Ca2+, both of which were inhibited by tetrodotoxin (10(-5) M). Nitrendipine (10(-5) M) and omega-conotoxin (5 x 10(-7) M) were ineffective on the veratridine-induced response. Nimodipine (10(-5) M) suppressed the veratridine-induced uptake of 45Ca2+ but also diminished the unstimulated uptake of 45Ca2+. The veratridine-induced uptake of Na+ was not influenced by nimodipine. Flunarizine (3 x 10(-6)-10(-5) M), as well as R 56865 (10(-6)-10(-5) M), attenuated the veratridine-induced uptake of both Na+ and 45Ca2+. In conclusion, the veratridine-induced uptake of Na+ and 45Ca2+ was shown to be closely correlated to the activity of Na+ channels but not to voltage-operated Ca2+ channels. Secondly, flunarizine and R 56865 seemed to evoke their effects by interfering with the permeability of Na+ channels. Since veratridine-induced uptake of Na+ and Ca2+ shares some similarities with ischaemia-induced uptake of Na+ and Ca2+, it is proposed, that flunarizine and R 56865 exert their anti-ischaemic effects by reducing ischaemia-induced Na+ and Ca2+ load, probably by inhibiting a TTX-sensitive Na+ channel.  相似文献   
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