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Atrioventricular nodal reentrant tachycardia (AVNRT) is a relatively common paroxysmal supraventricular tachycardia. This study investigated whether adenosine-5'-triphosphate (ATP) injection during sinus rhythm might be useful in the noninvasive diagnosis of dual AV nodal pathways. The study group consisted of 9 patients with slow/fast AVNRT and 11 control patients without antegrade dual AV nodal physiology (DAVNP). ATP (2.5 to 30 mg, in 2.5-mg increments was injected during sinus rhythm until signs of DAVNP (> or = 50 msec increase or decrease in AH or PR interval in two consecutive beats) or > or = second-degree AV block was observed. DAVNP was diagnosed by ATP test in all 9 patients with slow/fast AVNRT. DAVNP was observed by ATP test in 3 of the 11 control patients. Thus, the test had a sensitivity of 100% and specificity of 73%. ATP test given during sinus rhythm is useful for identifying patients with dual AV nodal pathways who are prone to AVNRT.  相似文献   
84.
The biochemical mechanism for resistance to Bacillus thuringiensis crystal proteins was studied in a field population of diamondback moths (Plutella xylostella) with a reduced susceptibility to the bioinsecticidal spray. The toxicity and binding characteristics of three crystal proteins [CryIA(b), CryIB, and CryIC] were compared between the field population and a laboratory strain. The field population proved resistant (greater than 200-fold compared with the laboratory strain) to CryIA(b), one of the crystal proteins in the insecticidal formulation. Binding studies showed that the two strains differ in a membrane receptor that recognizes CryIA(b). This crystal protein did not bind to the brush-border membrane of the midgut epithelial cells of the field population, either because of strongly reduced binding affinity or because of the complete absence of the receptor molecule. Both strains proved fully susceptible to the CryIB and CryIC crystal proteins, which were not present in the B. thuringiensis formulation used in the field. Characteristics of CryIB and CryIC binding to brush-border membranes of midgut epithelial cells were virtually identical in the laboratory and the field population.  相似文献   
85.
A 44-year-old woman with refractory follicular lymphoma underwent allogeneic stem cell transplantation (SCT) and achieved complete remission. Grade III acute graft-versus-host disease (GVHD) developed on day 23, but no chronic GVHD occurred. The patient developed severe erosion with bullous lesions in the oral cavity 18 months after SCT. At that time, the lymphoma remained in complete remission, and she had no clinical or laboratory findings suggesting chronic GVHD. A biopsy of the oral mucosa showed moderate lymphoplasmacytic infiltration and subepidermal bullae, and direct immunofluorescence staining demonstrated linear deposition of C3 at the dermo-epidermal junction. An immunoblotting assay using human epidermal extracts confirmed the presence in her serum of an antibody against the 230-kd bullous pemphigoid antigen 1 (BPAG1). A diagnosis of cicatricial pemphigoid (CP) was made, and complete resolution of the CP was achieved with pred-nisolone therapy. The occurrence of autoimmune blistering diseases is rare after allogeneic SCT.  相似文献   
86.
[Purpose] The purpose of this study was to clarify the relationship between acceleration and joint movement by synchronizing accelerometers and a three-dimensional motion analysis system, and to show the utility of an accelerometer as a postural control assessment tool. [Subjects and Methods] Head, lumbar, shank accelerations and various joint angles during single-leg standing were measured of 20 healthy males. Root mean squares of acceleration and joint angle were calculated. Fast Fourier transform analysis was performed for head, lumbar, and shank accelerations, and the median frequencies were calculated. Then, principal component analysis was performed for the median frequency of each acceleration. Stepwise multiple regression analysis was also used to examine the relationship between joint angle and acceleration. [Results] The score of the first principal component was highest for shank acceleration, while that of the second principal component was highest for lumbar and head accelerations. In multiple regression analysis, hip flexion/extension and adduction/abduction were identified as variables associated with head acceleration. [Conclusion] We were able to confirm the aggregation of acceleration into two components, which we interpreted as postural control strategies using primarily the ankle and hip joints. Furthermore, though multiple regression analysis, we were able to clarify the joint movement indicated by acceleration of each segment.Key words: Postural control, Acceleration, Ankle sprain  相似文献   
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We report a case of HLA-B52-positive Behçet disease accompanied by multiarterial lesions. A 24-year-old woman was suffering from sporadic high fever and recurrent oral and genital ulcers, and laboratory data revealed severe inflammation. A diagnosis of Behçet disease was made. Magnetic resonance angiography, ultrasound study, and computed tomographic angiography demonstrated multiarterial lesions that had caused no symptoms. These noninvasive examinations were extremely useful in evaluating asymptomatic early vascular lesions.  相似文献   
89.
BACKGROUND & AIMS: T helper (Th) 1 and Th2 cell subsets significantly influence the pathological features of inflammation in the gastrointestinal tract in a distinct manner. It is now established that the transfer of CD4(+)CD45RB(Hi) (RB(Hi)) T cells to either severe combined immunodeficient (SCID) or recombinase activation gene 2-deficient (RAG(-/-)) mice results in a severe granulomatous hypertrophic colitis mediated by Th1 cells. We have modified this approach to address the role of Th2 cells. METHODS: RB(Hi) T cells from wild-type (Wt) mice or mice genetically predisposed to Th2 responses (interferon-gamma-defective [IFN-gamma(-/-)]) with or without B cells were transferred to T cell receptor (TCR)-beta and delta-chain-defective (TCR(-/-)) or SCID mice. RESULTS: Transfer of Wt RB(Hi) T cells induced wasting disease with severe colitis in the TCR(-/-) mice. In contrast, IFN-gamma(-/-) RB(Hi) T cells induced severe weight loss and hypoalbuminemia without significant inflammation in the colon. The small intestine of these mice exhibited villus atrophy, a decrease in brush-border enzymes, reduced enterocyte proliferation, and an increased number of goblet cells. The presence of B cells was necessary for these changes, because SCID recipients required cotransfer of B cells, together with IFN-gamma(-/-) RB(Hi) T cells for ileal lesions to develop. Treatment of TCR(-/-) recipients of IFN-gamma(-/-) RB(Hi) T cells with anti-IL-4 mAb abrogated both the wasting disease and the villus atrophy. CONCLUSIONS: Dysregulated Th2 cells cause atrophic changes and goblet cell transformation in the small intestinal epithelium and wasting disease mediated by excess interleukin-4 and B cells.  相似文献   
90.
This case report describes a hairy B cell lymphoproliferative disorder (HBLD) with clinical and hematological features resembling hairy cell leukemia. The patient was a 29-year-old female who demonstrated atypical lymphocytes in her peripheral blood. Physical examination demonstrated splenomegaly, but there were no palpable superficial lymph nodes. Hematological examination showed a leukocyte count of 10.6 x 10(3)/mm3 with 41% atypical lymphocytes. Bone marrow examination showed a normal cellular and an atypical lymphocyte count of 42%. The atypical lymphocytes had microvilli and prominent membranous ruffles on their surfaces. Atypical lymphocytes expressed CD5- CD10- CD11c+ CD19+ CD20+ CD23- CD25- on the surface of the cells on examination by with a fluorescence activated cell sorter. Although these findings were similar to hairy cell leukemia, Japanese variant, the surface marker of the kappa chain and lambda chain was unbiased and studies of immunoglobulin gene rearrangements and expression showed polyclonal proliferation of B cells. Therefore, we diagnosed this patient as having HBLD. Because she did not demonstrate anemia or thrombocytopenia, she is not currently receiving medication. To date, the atypical lymphocyte count has not changed.  相似文献   
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