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121.
The hypoglycemic effect of the rhizomes of Polygala senega L. var. latifolia Torrey et Gray (Polygalaceae) was investigated in normal and KK-Ay mice, one of the model animals of non-insulin dependent diabetes mellitus (NIDDM). The n-butanol extract of senega rhizomes (SN) (5 mg/kg) reduced the blood glucose of normal mice from 191 +/- 3 to 120 +/- 3 mg/dl 4 hours after intraperitoneal administration (P < 0.001), and also showed a significant decrease in the glucose level of KK-Ay mice from 469 +/- 38 to 244 +/- 14 mg/dl under similar conditions (P < 0.001). But streptozotocin-induced diabetic mice did not experience a change in the blood glucose after administration of SN. We propose that the hypoglycemic effect of SN occurs without altering the insulin concentration. Moreover, SN needs the presence of insulin in order to act. In addition, one of the active components of the hypoglycemic effect was identified as a triterpenoid glycoside, senegin-II.  相似文献   
122.
Intradialytic exercise may improve hemodialysis efficiency. Because exercise interferes with thermal energy and fluid balance, relative blood volume changes (deltaBV%), arterial blood temperatures (T(art)), mean arterial blood pressures, and heart rates (HR) were measured using different dialysate temperatures (Tdia). Four stable patients (age, 49.9 +/- 7.7 years) were studied during 22 treatments that either maintained Tdia at 35.9 degrees C +/- 0.1 degrees C (standard) or provided maximum extracorporeal cooling (cool, Tdia = 34.8 degrees C +/- 0.8 degrees C) in attempts to maintain a constant T(art). Patients exercised for 1 hr at a resistance of 21 +/- 5 W on a stationary bicycle ergometer. Energy expenditure monitored by indirect calorimetry increased from 117 +/- 38 W (baseline) to 338 +/- 116 W (exercise). Mean arterial blood pressures increased by 7 +/- 7 mmHg with cool Tdia, but remained unchanged (-1 +/- 4 mmHg) with standard Tdia (p < 0.05). However, the increase in T(art) was smaller with cool (0.1 degrees C +/- 0.3 degrees C) than with standard (0.3 degrees C +/- 0.2 degrees C) Tdia (p < 0.05). The larger increase in O2 uptake per change in HR (68 +/- 56 vs 38 +/- 17 ml/beat) indicated an increase in stroke volume when cool dialysate was used (p = NS). Exercise produced a small (0.95% +/- 0.95%), but significant, decrease in deltaBV% that reversed at the end of exercise. Intradialytic exercise was well tolerated, especially when Tdia was lowered such that hemodynamic stress to dissipate excess heat through the cutaneous circulation was reduced and blood pressure stability was improved.  相似文献   
123.
Approximately 40% of Hodgkin's disease (HD) cases in Western countries carry Epstein-Barr virus (EBV) in the malignant Hodgkin-Reed-Sternberg (H-RS) cells. HLA class I-restricted cytotoxic T lymphocytes (CTLs) with specificity for viral antigens expressed in H-RS cells therefore have therapeutic potential. However, a prerequisite for CTL therapy is that the tumor target be capable of processing and presenting endogenously expressed antigens via the transporter associated with antigen processing (TAP)-dependent HLA class I pathway. We have assessed the antigen-presenting phenotype of H-RS cells in two ways. First, immunohistochemical analysis of 38 HD biopsies showed that H-RS cells were uniformly TAP1/TAP2-positive and expressed HLA class I in the majority (18 of 24, 75%) of EBV-positive cases compared with only 4 of 14 (29%) of EBV-negative cases. Second, using a panel of 5 H-RS cell lines, we showed that 4 of 5 could process and present EBV proteins to HLA class I-restricted EBV-specific CTL clones. Others have reported that human interleukin-10 (IL-10), which is expressed by H-RS cells in the majority of EBV-positive HD cases, can abrogate CTL recognition in some circumstances. However, IL-10 pretreatment of the H-RS lines or of the EBV-specific CTLs had no such effect in this system. These results support the possibility that EBV-specific CTLs may be used to treat virus-positive HD.  相似文献   
124.
Murine collagen-induced arthritis (CIA) is characterized by pannus formation, cell infiltration, and cartilage erosion, and shares histologic and immunologic features with rheumatoid arthritis. Numerous cytokines are reportedly associated with RA and/or CIA; however, their mechanistic role is not clear. To determine the role of IL-12 in CIA, DBA/1 LacJ mice were administered 3 x 10(8) plaque-forming units of mIL-12 i.p. in a nonreplicating adenoviral vector (AdIL-12) on day 25 following primary type II collagen immunization. Our studies demonstrated that systemic transient overexpression of IL-12 accelerated disease progression and augmented the arthritis severity relative to mice expressing a replication-deficient, E1-deleted Ad5 construct. A likely mechanism for this increase in pathology was the increase in the expression of cytokines and chemokines known to play a proinflammatory role in disease. In particular, levels of murine IFN-gamma were significantly increased in mice overexpressing AdIL-12 relative to the replication-deficient, E1-deleted Ad5 construct. Interestingly, the C-X-C chemokine murine macrophage inflammatory protein-2, as well as the C-C chemokines murine monocyte chemoattractant protein-1 and murine macrophage inflammatory protein-1alpha were up-regulated by AdIL-12 relative to controls. In an additional set of studies, neutralization of endogenous IL-12 in CIA mice was shown to delay disease onset and attenuate disease severity. IFN-gamma levels in the mice receiving anti-IL-12 were significantly decreased in joint homogenates. These studies demonstrate that IL-12 is an important cytokine involved in controlling the production of chemokines/cytokines leading to the evolution of experimental arthritis.  相似文献   
125.
The spatial distribution of metabolite signal intensities can be measured within entire sections of the brain by proton magnetic resonance spectroscopic imaging (1H-MRSI). A group of six patients (4 unrelated girls and 2 brothers from 5 families) with childhood ataxia with diffuse CNS hypomyelination (CACH) underwent long-echo-time, single-slice 1H-MRSI. Relative to controls, there was a decrease in the signal intensity of N-acetylaspartate, choline, and creatine throughout the white matter in all six patients. We identified lactate signals in white matter in three of them with advanced disease. The degree of white matter involvement was not homogeneous over the entire patient group, but did correlate with clinical presentation. Deep and posterior white matter tended to be more involved. There were no 1H-MRSI abnormalities in the gray matter. 1H-MRSI findings suggest that this syndrome is secondary to a metabolic defect causing hypomyelination, axonal degeneration, and, in the most compromised cases, accumulation of lactate. This study shows that CACH is not limited to girls.  相似文献   
126.
It is now apparent that distinction between the so-called malignant histiocytosis and lymphoma can be made using panels of established immunohistochemical markers and/or genotypic analysis. Many, if not all, of the previously diagnosed cases of malignant histiocytosis have been shown to be of lymphoid, rather than histiocytic, lineage. We report a rare case of colonic histiocytic neoplasm accompanied by a lymphoreticular dissemination that mimicked that of malignant histiocytosis. In addition, barium studies and computed axial tomography confirmed an intussusception that subsequently developed. The histiocytic nature of the neoplastic cells was supported by immunohistochemical, ultrastructural, and cytochemical studies. To our knowledge our case may represent the fifth documented case of a histiocytic malignancy reported in the literature. The relationship among the various cases will be discussed as well as the significance of the focal S-100 immunoreactivity observed in the present case.  相似文献   
127.
128.
Candida parapsilosis should be recognized by primary care physicians as an important nosocomial pathogen, which is also frequently associated with sporadic skin and appendage infections. Its association with environmentally acquired skin ulcers can mimic fixed cutaneous sporotrichosis.  相似文献   
129.
Capillary electrochromatography, CEC, is a hybrid of CE and HPLC and is rapidly gaining interest as a potential complementary technique. This paper provides an overview of literature concerning the separation of acidic compounds by CEC which fall into three distinct groups. These groups are those performed using capillaries packed with novel or unique stationary phases designed for CEC, and a smaller group where standard HPLC stationary phases packings such as ODS has been used. The third group involves the use of surface coated capillaries. This paper reviews the separation of acidic compounds by CEC and also includes a number of novel applications to illustrate the separation approaches and the analytical performance possible.  相似文献   
130.
PURPOSE: To evaluate the impact of foscarnet on the longevity of persons with human immunodeficiency virus, type 1 (HIV-1) infection and cytomegalovirus (CMV) retinitis. PATIENTS AND METHODS: A cohort of 24 patients with acquired immunodeficiency syndrome (AIDS) and CMV retinitis received sodium phosphonoformate (foscarnet) as part of a controlled efficacy trial at the National Institutes of Health. Foscarnet was continued for as long as it was tolerated. Antiretroviral therapy was given to the patients as tolerated. Long-term follow-up was available on all patients. RESULTS: Seventeen patients received zidovudine during or after receiving foscarnet, 2 patients received dideoxyinosine, 2 patients zidovudine and dideoxyinosine, and 3 patients received no specific antiretroviral agent. Patients received foscarnet for a mean of 6.2 months (median, 4 months; range, 10 days to 22 months). Ten patients required a change to ganciclovir therapy at some time after receiving foscarnet. The median time from the diagnosis of CMV retinitis until death was 13.5 months (range, 3 to 34 months). Patients lived longer than untreated or ganciclovir-treated historical controls with AIDS and CMV retinitis. There was no difference in the survival of patients treated with foscarnet at the time of diagnosis and those patients treated with foscarnet only after progression of their CMV retinitis. CONCLUSIONS: These data suggest that foscarnet may prolong the survival of persons with AIDS and CMV retinitis and should be the initial treatment of choice in these patients.  相似文献   
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