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排序方式: 共有5473条查询结果,搜索用时 15 毫秒
81.
82.
S Petrash A Liebmann-Vinson MD Foster LM Lander WJ Brittain CF Majkrzak 《Canadian Metallurgical Quarterly》1997,13(5):635-639
Endurance exercise training increases fat oxidation during large muscle mass exercise. Although the source of this fat has been thought to be plasma free fatty acids (FFA) released from adipose tissue, the training-induced decrease in lipolytic hormonal responses to exercise is not consistent with this concept. The purpose of this communication is to review findings, from our laboratory indicating that, in young healthy subjects, endurance exercise training reduces plasma FFA turnover and oxidation during moderate intensity prolonged 2-leg cycling while simultaneously enhancing depletion of triglycerides from the active musculature. Evidence is presented that metabolism of intramuscular triglycerides can explain the increase in total fat oxidation observed in the trained state during large muscle mass exercise. However, these results may not be applicable to exercise involving small muscle groups, a distinction that is likely to be important in explaining the apparent conflict between our findings and those from other laboratories where experimental conditions were different. In summary, for large muscle mass exercise up to 2 h in duration, plasma FFA are a less important fuel source in the trained state, and intramuscular triglycerides supply the major portion of the increase in oxidized fatty acids. 相似文献
83.
M Agelli P Dello Sbarba ED Halay RA Faris DE Hixson LM Reid 《Canadian Metallurgical Quarterly》1997,29(3):205-217
BACKGROUND AND OBJECTIVES: We operated on three patients with leiomyosarcoma of the inferior vena cava. METHODS: Complete excision was possible in all three patients. RESULTS: One patient developed widespread metastasis at 23 months, one patient is alive with no evidence of disease at 70 months, and one patient is alive at 15 months. The third patient had subcutaneous and pulmonary metastases at the time of presentation, which are radiologically nondetectable at present following postoperative chemotherapy. CONCLUSIONS: The clinicopathologic features, prognostic factors, and treatment of 130 cases found in a comprehensive literature search and our three cases are reported. 相似文献
84.
Steven S Fu Miles McFall Andrew J Saxon Jean C Beckham Timothy P Carmody Dewleen G Baker Anne M Joseph 《Nicotine & tobacco research》2007,9(11):1071-1084
We conducted a systematic review of what is known about the relationship between post-traumatic stress disorder (PTSD) and smoking to guide research on underlying mechanisms and to facilitate the development of evidence-based tobacco treatments for this population of smokers. We searched Medline, PsychINFO, and the Cochrane Central Register of Controlled Trials and identified 45 studies for review that presented primary data on PTSD and smoking. Smoking rates were high among clinical samples with PTSD (40%-86%) as well as nonclinical populations with PTSD (34%-61%). Most studies showed a positive relationship between PTSD and smoking and nicotine dependence, with odds ratios ranging between 2.04 and 4.52. Findings also suggest that PTSD, rather than trauma exposure itself, is more influential for increasing risk of smoking. A small but growing literature has examined psychological factors related to smoking initiation and maintenance and the overlapping neurobiology of PTSD and nicotine dependence. Observational studies indicate that smokers with PTSD have lower quit rates than do smokers without PTSD. Yet a few tobacco cessation treatment trials in smokers with PTSD have achieved quit rates comparable with controlled trials of smokers without mental disorders. In conclusion, the evidence points to a causal relationship between PTSD and smoking that may be bidirectional. Specific PTSD symptoms may contribute to smoking and disrupt cessation attempts. Intervention studies that test behavioral and pharmacological interventions designed specifically for use in patients with PTSD are needed to reduce morbidity and mortality in this population. 相似文献
85.
Most (98%) of the fat in human milk is present as triglycerides. This paper describes the use of a clarification procedure that enables the level of human milk fat to be determined by measurement of glycerol released by enzymic hydrolysis of triglycerides. The method requires only 10-50 microliters milk, thus presenting a possible technique for work with small mammals, and is suitable for use with autoanalysers, permitting rapid sample throughput. 相似文献
86.
A novel method for the crosslinking of poly(ethylene terephthalate) fibers is described using 1,6‐hexanedisulfonyl azide, 1,3‐benzenedisulfonyl azide, and 2,6‐naphthalenedisulfonyl azide. The azides are diffused into poly(ethylene terephthalate) fibers (Dacron) from perchloroethylene solution, and the fibers are heat treated to bring about decomposition of the sulfonyl azide and give rise to crosslinking. A study is made of the mechanical and thermal properties of the resultant fibers, which are changed considerably in comparison to the untreated fiber. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1517–1527, 2002 相似文献
87.
The possible hypocholesterolaemic properties of milk and fermented milk products have been investigated in groups of albino rats given a basal diet, basal diet plus cholesterol, and basal diet plus cholesterol together with whole milk or standard or bifidus yogurt. The yogurts were fortified with skim milk powder, condensed whey or lactose-hydrolysed condensed whey. After 30 d, triacylglycerols, total cholesterol, HDL-cholesterol and LDL-cholesterol were measured in serum. Whole milk and ordinary yogurt had no hypocholesterolaemic effect, but standard yogurt containing lactose-hydrolysed condensed whey and all bifidus yogurts lowered serum cholesterol. In general, yogurts changed HDL-cholesterol little, but tended to raise triacylglycerols. There was marked lowering of LDL-cholesterol in rats given either type of yogurt fortified with whey proteins. This study has demonstrated in a rat model that bifidus yogurts and yogurts fortified with whey proteins can reduce total and LDL-cholesterol, and suggests that if they have the same effect in human subjects they have potential value in cholesterol-lowering diets. 相似文献
88.
S Horenblas H van Tinteren JF Delemarre LM Moonen V Lustig EW van Waardenburg 《Canadian Metallurgical Quarterly》1993,149(3):492-497
We analyzed the management of regional lymph nodes in 110 patients with squamous cell carcinoma of the penis treated at the Netherlands Cancer Institute between 1956 and 1989 with curative intent. Of 66 patients who presented with unsuspected nodes 57 were placed on a surveillance program, while lymph node dissection was performed in 5 (with adjuvant external radiation therapy in 1) and 4 were treated with external radiation therapy only. The management of 40 patients with clinically suspected nodes included surveillance in 5, lymph node dissection in 27 (with adjuvant radiotherapy in 11), biopsy in 4 and external radiation therapy in 4. Postoperative radiotherapy had been given if more than 2 nodes were involved or when extracapsular growth was observed. Overall, 25 patients had a regional recurrence, 5 of whom could be cured subsequently. All regional recurrences developed within 2 years after primary treatment. Analysis showed 100% survival in histologically proved node negative patients (stage pN0). The success of lymph node dissection was related to the extent of the metastatic spread and to the number of involved nodes. Patients with 1 positive node and unilateral inguinal involvement showed a statistically significant survival advantage compared to patients with more extensive spread. Considering the indications for node dissection we found a clear relationship among T category, grade and the probability of lymph node invasion. Patients with stage T1 tumors and stage T2, grades 1 and 2 tumors presented significantly less often with lymphatic invasion than those with other categories of disease and were less likely to have a regional recurrence after treatment of the primary tumor only. In these categories we recommend surveillance of the regional lymph nodes in patients who present with unsuspected nodes. However, patients with stage T2 grade 3, stage T3 and operable stage T4 tumors should undergo an immediate inguinal node dissection because of the high probability of clinically occult lymph node invasion (in our material more than 50%). With respect to the extent of the node dissection, we found that the likelihood of spread to the contralateral and/or pelvic regions was related to the number of invaded nodes in the inguinal region. We recommend contralateral node dissection and unilateral pelvic node dissection when 2 or more positive nodes are found in the dissected groin specimen. Primary pelvic node dissection should be performed in patients who present initially with cytologically or biopsy proved positive inguinal nodes.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
89.
90.
We examined the ability of anti-human recombinant interleukin-2 (hu rIL-2) monoclonal antibody DMS-1.10 to increase serum half-life of hu rIL-2, and the effect of this complex on inhibition of tumor progression in a B16-F10 murine melanoma model. In C57B1/6 mice, intravenous (i.v.) injection of DMS-1.10 premixed with 1 x 10(4) units (U) of hu rIL-2 at a 1:1 molar ratio extended serum half-life greater than 10-fold (222 min) when compared to the same dose of hu rIL-2 alone (20 min). In a murine tumor model, multiple intraperitoneal (i.p.) injections of non-neutralizing DMS-1.10 premixed with hu rIL-2 at a 5:1 molar ratio reduced the growth rate of subcutaneous (s.c.) B16-F10 tumor in C57B1/6 mice by 64% when compared to PBS and irrelevant antibody treated controls. Although similar treatment with hu rIL-2 alone reduced tumor growth rate by 46%, it was significantly less effective than the premixed treatment. Results from a flow cytometry assay confirm B16-F10 does not have IL-2 receptors, precluding direct inhibition of tumor growth by hu rIL-2 treatments. We propose that therapeutic efficacy of hu rIL-2 is improved by prolonging the in vivo half-life with an anti-IL-2 antibody, thus augmenting hu rIL-2 bioactivity and enhancing the hosts immune response against tumor. 相似文献