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Eleven men consumed a basal diet alone and with cellulose (Na-carboxymethylcellulose, locust bean gum, or karaya gum) added at 7.5 g fiber per 1000 calories for 4 wk each. Food, urine, and fecal composites were collected during the last 8 d of each feeding period. Bowel transit time was not significantly affected; however, total dry fecal weight was significantly increased after the refined fibers compared with that after the basal diet. Adding refined fibers to the basal diet did not significantly affect apparent mineral balance of calcium, magnesium, manganese, iron, copper, or zinc, with the exception of a negative mineral balance for manganese with carboxymethylcellulose. Karaya gum had a mean positive balance for all minerals tested. These results indicate that the hypocholesterolemic effect of the fibers that form gels occurs without compromising mineral balance in those subjects consuming Recommended Dietary Allowance levels of the minerals studied.  相似文献   
34.
Between 1 January and 31 March 1986, 2434 strains of Haemophilus influenzae collected from 23 laboratories in the United Kingdom were examined. With the same criteria as previous studies in 1977 and 1981 the prevalence of resistance was: ampicillin 7.8% (6.2% beta-lactamase producers and 1.6% non-producers), tetracycline 2.7%, chloramphenicol 1.7%, trimethoprim 4.2%, and sulphamethoxazole 3.5%. of the 87 capsulated strains, 15 produced beta-lactamase, nine were resistant to ampicillin but did not produce beta-lactamase, and two strains, one of which produced beta-lactamase, were resistant to chloramphenicol and tetracycline. Since 1977 the prevalence of resistance to ampicillin, chloramphenicol, and trimethoprim has increased significantly. During 1981-6 strains resistant to ampicillin but not producing beta-lactamase and strains resistant to trimethoprim have significantly increased.  相似文献   
35.
BACKGROUND: Since 1997, a number of trials have shown promising results in treating generalized vitiligo with narrowband ultraviolet B (UVB) both in adults and children. However, there is little knowledge concerning the duration and permanency of the treatment-induced repigmentation. OBJECTIVE: Our main objective was to perform a follow-up trial of successfully treated patients receiving narrowband UVB for generalized vitiligo. METHODS: We have investigated to what degree the treatment-induced repigmentation remains stable for up to 2 years post-treatment. We performed an initial open trial including 31 patients with generalized vitiligo. They received narrowband UVB thrice weekly for up to 12 months. Patients experiencing > 75% repigmentation were defined responders and were included in the follow-up trial. Responders were followed every 6 months for up to 2 years after cessation of treatment. We observed the pigmentation status and registered any changes indicating loss of pigmentation and relapse. RESULTS: Eleven of the 31 treated patients were included in the follow-up trial. Six patients had relapse and five patients had stable response 24 months after cessation of treatment. Four out of six relapses were within 6 months post-treatment. CONCLUSION: In our study population of 31 patients with generalized vitiligo, five patients (16%) experienced > 75% stable repigmentation 2 years after cessation of a treatment programme of up to 1 years narrowband UVB therapy.  相似文献   
36.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
37.
Summary.  Previously we demonstrated that domain 5 (D5) of high-molecular-weight kininogen (HK) inhibits neovascularization in the chicken chorioallantoic membrane (CAM) assay and further found that kallikrein cleaved HK (HKa) inhibited FGF2-and VEGF-induced neovascularization, and thus was antiangiogenic. In this study, we sought to demonstrate whether uncleaved HK stimulates neovascularization and thus is proangiogenic. The chick chorioallantoic membrane was used as an in ovo assay of angiogenesis. Low-molecular-weight kininogen stimulates angiogenesis, indicating that D5 is not involved. Bradykinin stimulates neovascularization equally to HK and LK and is likely to be responsible for the effect of HK. A murine monoclonal antibody to HK (C11C1) also recognizes a similar component in chicken plasma as detected by surface plasmon resonance. Angiogenesis induced by FGF2 and VEGF is inhibited by this monoclonal antibody and is a more potent inhibitor of neovascularization induced by VEGF than an integrin αvβ3 antibody (LM 609). Our postulate that C11C1 inhibits the stimulation of angiogenesis by HK was confirmed when either C11C1 or D5 completely inhibited angiogenesis in the CAM induced by HK. Growth of human fibrosarcoma (HT-1080) on the CAM was inhibited by GST-D5 and C11C1. These results indicate HK is proangiogenic probably by releasing bradykinin and that a monoclonal antibody directed to HK could serve as an antiangiogenic agent with a potential for inhibiting tumor angiogenesis and other angiogenesis-mediated disorders.  相似文献   
38.
Several major prospective studies that have examined the relation between type A behavior and cardiac mortality have failed to find an association. Since psychosocial factors have been implicated in the etiology of sudden cardiac death, it is possible that this association may emerge if sudden cardiac death is distinguished as an outcome distinct from other cardiac mortality. Predictors of sudden death and other cardiac outcomes were examined using data from the Recurrent Coronary Prevention Project, a 4.5-year prospective clinical trial of 1,012 postinfarction patients begun in San Francisco in 1978. A unique set of risk factors was found for the differing outcomes: sudden cardiac death had predominantly psychosocial predictors while nonsudden cardiac death and nonfatal recurrences were predominantly predicted by biologic factors. Type A behavior was an independent predictor of sudden, but not nonsudden, cardiac death in this population (p = 0.04). These results are the first demonstration of a direct relation between stress and sudden cardiac death in a large prospective clinical study, and provide insight into the failure of past prospective studies to find an association between type A behavior and cardiac mortality.  相似文献   
39.
We describe a simple, quick ultrasound screening test for CDH, and its use in a prospective study of babies with a 'high risk' factor, over one year from January 1987. From a birth population of 3,879, 812 hip scans were performed on 406 babies and 98 babies were abnormal. So far, there have been no late cases of CDH. Family history, breech malposition, and postural foot deformities were confirmed to be important risk factors, but babies with a simple click were equally at risk. Our early results indicate that a large proportion of the potential late cases are contained within our extended high-risk group.  相似文献   
40.
High doses of BHA cause hyperplasia and subsequent neoplasia in the rodent forestomach and can inhibit gastric prostaglandin (PG) synthesis in vitro. This paper examines the hypothesis that BHA induced forestomach hyperplasia occurs in response to a reduction of gastric mucus, with consequent irritation of the forestomach. This could result from inhibition of the formation of the PG's which mediate the synthesis and release of protective mucus. Groups of 10 rats received 0 or 2% BHA in the diet for 1 or 3 weeks and a positive control group was fed a diet containing indomethacin (3.5 mg/kg), a potent inhibitor of PG synthesis. After 1 week BHA caused focal erosion and ulceration of the forestomach consistent with an irritant effect, but 2 weeks later the epithelium was healed, thickened and markedly hyperplastic. Histochemical staining for mucus showed that the development of forestomach hyperplasia was associated with increased amounts of gastric and duodenal mucus and increased numbers of serotonergic-cells in the gastric and duodenal epithelium. In contrast, indomethacin caused a marked reduction in both gastric and Brunner's gland mucus. Neither BHA nor indomethacin exerted an effect on one specific type of mucus (viz: neutral, acidic or mixed) in the stomach. These results do not support the hypothesis that forestomach hyperplasia arises from an inhibition of either the synthesis or release of gastric mucus. It is possible that the increased numbers of serotonergic-cells are related to the initial ulcerative, or subsequent hyperplastic response.  相似文献   
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