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排序方式: 共有233条查询结果,搜索用时 15 毫秒
91.
92.
Nutcracker syndrome: diagnosis with Doppler US   总被引:16,自引:0,他引:16  
Kim  SH; Cho  SW; Kim  HD; Chung  JW; Park  JH; Han  MC 《Radiology》1996,198(1):93
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93.
OBJECTIVE: To describe the prevalence of oral lesions in HIV-infected women, and to determine the association of oral lesions with the level of immunosuppression and the route of transmission. PATIENTS: In a retrospective, cross-sectional study, a cohort of 70 HIV-infected women (median age: 32.5 y; median CD4+-cell count 262 per μl) comprising 18% of all HIV-infected individuals (n = 389) was selected in an outpatient clinic. Oral lesions strongly associated with HIV-infection were evaluated. RESULTS: The overall prevalence of oral lesions was 27/70 (39%). Among HIV-infected women with CD4+-cell counts <200 per μl, the prevalence was 65% (19/29); and with counts >200 per μl, the prevalence was 27% (11/41). The prevalence of candidiasis and hairy leukoplakia was similar among those infected heterosexually or by intravenous drug use. CONCLUSIONS: As reported in men, these findings demonstrate that oral lesions are common in HIV-infected women. Candidiasis is more likely to occur at low CD4+-cell counts, whereas no difference was seen regarding the level of immunosuppression and hairy leukoplakia. Interestingly, the route of transmission does not play a role regarding the presence of oral lesions among HIV-infected women.  相似文献   
94.
To determine if pulmonary perfusion was improved in acute pulmonary embolism after therapy with recombinant human tissue-type plasminogen activator (rt-PA), lung scans were obtained before and a mean of 22 hours after therapy in 19 patients. The posttherapy lung scans were compared with baseline, pretherapy scans with use of two semiquantitative methods--an anteroposterior view method, similar to that used in the Urokinase Pulmonary Embolism Trial, and a segmental method that emphasized pulmonary anatomy. There was an improvement in the defect score from 0.35 to 0.14 (P less than .01) when the anteroposterior view method was used and from 0.37 to 0.16 (P less than .01) when the segmental method was used. These encouraging results in the early posttherapy period suggest that rt-PA is especially effective in improving regional perfusion after pulmonary embolism and that a larger controlled trial of therapy with rt-PA for acute pulmonary embolism should be performed. Scoring lung scans with a segmental method is feasible and appropriate for present-day lung scan technique and should be considered in future studies.  相似文献   
95.
Induction of gap junctional communication (GJC) and antioxidant activities of carotenoids have been considered as biochemical mechanisms underlying the cancer-preventive properties of these compounds. beta-Carotene and other carotenoids, including those lacking provitamin A activity, proved to be active in both these parameters. The beta-carotene analogs retrodehydro-beta-carotene, echinenone, cryptoxanthin (3-hydroxy-beta-carotene), 4-hydroxy-beta-carotene and canthaxanthin stimulate GJC and efficiently deactivate singlet molecular oxygen. beta-Carotene is less active than its retro-dehydro analog with respect to (1)O2-quenching but GJC is similar. The five- membered ring analog of canthaxanthin, dinor-canthaxanthin, has less effect on GJC as compared with the parent compound but exhibits increased singlet oxygen quenching. Straight-chain polyene dialdehydes are quenchers of singlet oxygen, the efficiency increasing with the number of conjugated double bonds. However, none of these compounds significantly induce GJC. These data indicate that the two properties of carotenoids addressed in this study may operate independent of each other.   相似文献   
96.
Northern blot analysis was used to assess the level of expression of five protooncogenes and histone H3 in the bone marrow cells of patients with acute nonlymphocytic leukemia (ANLL). The relationship between the level of gene expression and the clinical characteristics of the disease and response to therapy was studied. The levels of expression of c-myc and c-myb are weakly correlated and are unrelated to French- American-British (FAB) type of ANLL. The levels of expression of c-fms, c-fes, and c-fos are highly correlated with each other and are highest in leukemia with a monocytic component (c-fms v FAB = .71, c-fes v FAB = .75). High levels of c-myc expression are associated with a high probability of not responding to remission induction therapy (P = .004). The converse is true for c-fms expression levels. High levels of expression of c-myc or c-myb are associated with short remissions (P = .059 and .065, respectively), perhaps because they are associated with a high capacity for leukemic cell self-renewal and/or an inability of leukemic cells to differentiate in response to chemotherapy.  相似文献   
97.
98.
Background Acne vulgaris is one of the most common skin disorders, and androgen is known to play a key role in the development of acne. However, the exact genetic mechanism by which androgen receptor (AR) gene affects acne development is still unclear. Objective Our study aimed to investigate whether CAG and GGN polymorphism of the AR gene are associated with acne risk. Patients and methods Two hundred thirty‐eight patients and 207 controls were included in the study. The repeat lengths of the AR gene were determined by GeneScan analysis. Results Men with CAG < 23 and women with CAG < 24 had significant risk compared to those men with CAG ≥ 23 [odds ratio (OR), 2.07; 95% confidence interval (95% CI), 1.21–3.54] and women with CAG ≥ 24 (OR, 2.05; 95% CI, 1.18–3.56). In males, GGN repeats, considered independently of the CAG repeat, have no significant effect on the acne risk; however, when combined with CAG repeats, the acne patients exhibited significantly higher frequency of the haplotypes CAG < 23/GGN ≤ 23 (OR, 3.33; 95% CI, 1.10–10.07; P < 0.05) compared with the controls. Conclusion Our results of this study strongly indicated that a shorter CAG repeat length and specific haplotypes of AR attributed to the risk of acne development and thus could serve as a susceptibility marker.  相似文献   
99.
Unusual neuroradiological features of intracranial cysticercosis   总被引:2,自引:0,他引:2  
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100.
Trypanosoma brucei parasites are kinetoplastid protozoa that devastate the health and economic well-being of millions of people in Africa through the disease human African trypanosomiasis (HAT). New chemotherapy has been eagerly awaited due to severe side effects and the drug resistance issues plaguing current drugs. Recently, there has been an emphasis on the use of medicinal plants worldwide. Morinda lucida Benth. is a popular medicinal plant widely distributed in Africa, and several research groups have reported on the antiprotozoal activities of this plant. In this study, we identified three novel tetracyclic iridoids, molucidin, ML-2-3, and ML-F52, from the CHCl3 fraction of M. lucida leaves, which possess activity against the GUTat 3.1 strain of T. brucei brucei. The 50% inhibitory concentrations (IC50) of molucidin, ML-2-3, and ML-F52 were 1.27 μM, 3.75 μM, and 0.43 μM, respectively. ML-2-3 and ML-F52 suppressed the expression of paraflagellum rod protein subunit 2, PFR-2, and caused cell cycle alteration, which preceded apoptosis induction in the bloodstream form of Trypanosoma parasites. Novel tetracyclic iridoids may be promising lead compounds for the development of new chemotherapies for African trypanosomal infections in humans and animals.  相似文献   
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