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151.
We have used IL-10 gene knockout mice (IL-10T) to examine the role of endogenous IL-10 in the down-modulation of hepatic granuloma formation and lymphocyte responses that occurs in chronic infection with the helminth parasite Schistosoma mansoni. Although IL-10-deficient animals showed 20 to 30% mortality between 8 and 14 wk postinfection, they displayed no alterations in their susceptibility to infection and produced similar numbers of eggs as their wild-type littermates. The IL-10T mice displayed a significant increase in hepatic granuloma size at the acute stage of infection, which was associated with increased IFN-gamma, IL-2, IL-1beta, and TNF-alpha mRNA expression in liver and elevated Th1-type cytokine production by lymphoid cells. Despite developing an enhanced Th1-type cytokine response, the IL-10T mice showed no consistent decrease in their Th2-type cytokine profile. Surprisingly, although granulomatous inflammation was enhanced at the acute stage of infection, the livers of IL-10T mice displayed no significant increase in fibrosis and underwent normal immune down-modulation at the chronic stage of infection. Moreover, the down-modulated state could be induced in IL-10T mice by sensitizing the animals to schistosome eggs before infection, further demonstrating that the major down-regulatory mechanism is not dependent upon IL-10. We conclude that while IL-10 plays an important role in controlling acute granulomatous inflammation, it plays no essential role in the process of immune down-modulation in chronic schistosome infection.  相似文献   
152.
153.
The purpose of this study was to determine if ultrasonographic measurement of multiple cross-sectional areas combined with linear dimensions of the bladder could be used as a method of estimating bladder volume in the dog, and, if so, to compare the accuracy of this estimation with that described previously using linear measurements alone. Fifty-two live dogs undergoing investigation for urological disease and 37 fresh canine cadavers were used for bladder volume determination. Maximal length, depth, width, and area were measured from the maximal longitudinal and transverse sonograms in each living animal. In cadavers, the cross-sectional area of the longitudinal section of the bladder was measured at one centimeter intervals, and the measurements were summed. Based on sequential partial regression analysis, the cross-sectional area of the longitudinal section of the bladder and length were the best predictors of actual bladder volume in living animals. However, based on the cadaver experiment, the best predictor of actual bladder volume was summed parasagittal area alone, and, in cadavers, this was a much better predictor of actual bladder volume than the combination of the cross-sectional area of the longitudinal section of the bladder and length. The formula derived in living dogs using the cross-sectional area of the longitudinal section of the bladder and length gave a less accurate estimation of bladder volume than a previously published formula where only linear measurements were used.  相似文献   
154.
N-Nitroso-N-(3-keto-1,2-butanediol)-3'-nitrotyramine (NO-NTA) is a product of model browning system generated in the presence of sodium nitrite. The chemical structure of this compound has been confirmed by UV, mass and nuclear magnetic resonance, and infrared spectroscopy in our previous study. A two-stage transformation protocol was used to chemically transform the mouse embryo fibroblasts C3H10T1/2 cells. To initiate transformation, the cells were treated with benzo[a]pyrene (BaP) (0.1 mg/ml), and NO-NTA (0.01, 0.1 and 1 mg/ml) was employed subsequently to complete the transformation process. Malignant transformed foci were formed in BaP-initiated and NO-NTA promoted C3H10T1/2 cells after 8 wk. Cells treated with NO-NTA alone failed to induce transformation. However, cells initiated with BaP and promoted by cells initiated with BaP and promoted by NO-NTA demonstrated oncogenic properties. Cell lines transformed with NO-NTA-transformed colonies exhibited enhanced growth rate, anchorage independence and tumorigenicity in animals relative to parent cells. These results indicate that NO-NTA is a new tumour promoter and may induce tumour promotion by two-stage oncogenesis. Further studies on the mechanism of action of NO-NTA are now in progress.  相似文献   
155.
The purpose of this study was to determine the relationship between free-living daily physical activity and ambulatory measurements in peripheral arterial occlusive disease (PAOD) patients with intermittent claudication. Thirty-four older, nonsmoking PAOD patients with intermittent claudication (age=69.0 +/- 6.0 years, ankle/brachial index [ABI] =0.63 +/- 0.18) were recruited from the Vascular Clinic at the Baltimore Veterans Affairs Medical Center and from radio and newspaper advertisements. Energy expenditure of physical activity (EEPA) was determined by using doubly labeled water and indirect calorimetry techniques. Patients were also characterized on claudication distances and peak oxygen uptake during a graded treadmill test, 6-minute walking distance, weight, body mass index, and percent body fat. The claudication patients were sedentary, as EEPA was 362 +/- 266 kcal/day. EEPA was related to the 6-minute walk distance (369 +/- 68 meters; r=0.629, P<0.001), to the number of steps taken during 6 minutes (605 +/- 99 steps; r=0.485, P=0.008), to the treadmill distance to maximal claudication (313 +/- 131 meters; r=0.470, P=0.010), and to the time to relief of pain (6:21 +/- 3:57 min:sec; r=-0.417, P=0.017). None of the other ambulatory and body composition measurements were correlated with EEPA. In conclusion, a reduction in free-living daily physical activity was associated with a decrease in ambulatory ability and with more severe intermittent claudication in older PAOD patients.  相似文献   
156.
Triphasic waves (TWs) can be recorded on EEG in the course of several metabolic disorders, mainly hepatic encephalopathy. A case of acute encephalopathy due to naproxen intoxication is reported, in the course of which diffuse, bilateral and symmetrical TWs were recorded. Biochemical mechanisms that might determine both a complex encephalopathy and TWs are discussed.  相似文献   
157.
OBJECTIVE: To evaluate whether the Waterlow pressure sore risk (PSR) scale has prognostic significance for intensive care patients. DESIGN: A prospective study. SETTING: The surgical intensive care unit (ICU) of the University Hospital Rotterdam. PATIENTS: Data were evaluated from 594 patients who had been admitted to the ICU during the year 1994. METHODS AND RESULTS: Each patient was assessed daily with respect to their Waterlow PSR score and the development of pressure sores in the sacral region. Actuarial statistical methods were used to analyse the predictive value of the risk score. When a patient had a Waterlow PSR score > 25 on admission, the risk of developing a pressure sore was significantly increased compared to patients with a PSR score < 25. After admission, the daily Waterlow PSR scores obtained were significantly associated with the risk of developing a pressure sore. For each additional point this risk increased by 23% (95% confidence interval 17 to 28%). CONCLUSIONS: The Waterlow PSR scale provides the medical and nursing staff at an early stage with reliable information about the risk patients have in developing a pressure sore.  相似文献   
158.
The purpose of this work was to develop a method for measurement of the major forms of resistant starch (RS) in foods. The analytical procedure was chosen to mimic physiologic conditions, and included chewing as a prestep before incubation with pepsin, pancreatin and amyloglucosidase. The undigestible polysaccharides, including RS, were recovered by ethanol precipitation and subsequent filtration. RS was analyzed as total starch in the filter residue. The residues were also used for gravimetric determination of dietary fiber after correcting for remaining protein, ash and RS. The potentially available starch fraction was determined from analysis of glucose in the filtrate. The foods included were prepared to resemble products for which RS figures were available from in vivo measurements, and/or from analysis with other current in vitro methods. For six of these foods, and for three additional starchy materials, RS figures were compared with in vivo and/or in vitro data for identical products. The pooled standard deviation for the suggested RS method was 2.9%. A high correlation was obtained with in vivo figures from the literature for 19 realistic foods (r = 0.97; y = 0.77x + 0.45). After correction for RS, dietary fiber figures corresponded well with conventional gravimetric dietary fiber analysis for 14 starchy foods (r = 0.97). It is concluded that the procedure described here provides a convenient way to estimate RS content of realistic foods, allowing parallel determination of the potentially available starch fraction and dietary fiber.  相似文献   
159.
Interleukin 12 (IL-12) is a heterodimeric cytokine that has been demonstrated to have a major role in stimulating a cell-mediated antitumor response. IL-10, a product of T helper 2 lymphocytes, is its most potent inhibitor. The aim of this study was to investigate whether patients with colorectal cancer had an imbalance in production of IL-12 and IL-10 preoperatively, and whether this was associated with advanced disease at surgery. Blood was obtained before surgery from 60 patients with colorectal cancer and from 30 controls. Peripheral blood mononuclear cells were incubated with Staphylococcus aureus Cowan's strain 1 in vitro for 24 h to assess IL-12 expression after stimulation, and serum was used for IL-10 measurement. IL-12 and IL-10 levels were assessed by ELISA. A single pathologist staged the tumors according to the tumor-node-metastasis (TNM) and Dukes' classifications. Patients with colorectal cancer had significantly lower levels of IL-12 (P <0.001) and higher levels of IL-10(P = 0.004) compared to controls. In addition, lower levels of IL-12 were detected in those patients who were node positive (P<0.05), had Dukes' C lesions (P < or = 0.001), and T3 or T4 lesions (P<0.033) when compared to controls. Patients with Dukes' B and C lesions (P<0.01) and T3 and T4 lesions (P<0.05) also had higher levels of IL-10 compared to controls. This study is the first to demonstrate that patients with colorectal cancer have decreased IL-12 production and increased serum IL-10. This suggests an impaired T helper 1 cell-mediated antitumor response and provides some justification for exogenous IL-12 therapy or anti-IL-10 therapy in these patients.  相似文献   
160.
The purpose of this review was to give an answer to the question whether there are convincing data to support the hypothesis of an amino acid imbalance as one possible mechanism to explain overtraining syndrome. Animal studies point to an enhanced synthesis of the neurotransmitter 5-hydroxytryptamine through an amino acid imbalance at the blood-brain barrier with a preferable tryptophan uptake into the brain, resulting in premature fatigue. Human studies, however, show contradictory results, mainly because of nonstandardized methodology, so that a final conclusion cannot be made at present. BCAA supplementation in addition to standard carbohydrate ingestion during sustained exercise seems to be of no eminent advantage to delay fatigue. The overall results concerning the BCAA hypothesis to explain overtraining are inconclusive and require more controlled experimental research.  相似文献   
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