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51.
Understanding diet and energy balance as risk factors for breast, colon, and other cancers requires information on the contribution of each factor and of interactions among factors to cancer risk. Rodent models for breast cancer provide extensive data on effects of dietary fat and calories, energy balance, body weight gain, and physical activity on tumor development. Analyses of the combined data from many studies have shown clearly that quality and quantity of dietary fat and energy balance contribute independently to increased mammary gland tumorigenesis. These findings were seen in female rats fed diets high in fat (35-40% of calories) compared to rats fed control diets, with approximately 10% of calories as fat (Fay and Freedman, 1997, Breast Cancer Res. Treat. 46, 215-223). The methods used permit comparison of experimental and epidemiological data, and they may be useful in extrapolating between species and developing public health recommendations. In addition to the contributions of lifetime-diet composition, intake, energy balance, and physical activity to cancer risk, there are questions about the timing and duration of alterations in these factors and about the "dose-response" characteristics of cancer risk to the factors. Endocrine mechanisms may be significant in mammary gland tumor risk, but experimental and epidemiological data indicate that cancers at other sites, such as colon and liver, also are influenced by the factors listed. Other diet and lifestyle factors that influence energy, or specifically fat, metabolism may also affect risk for cancers that are promoted by increased intake of fat and calories. Studies of separate and interactive effects of dietary fat, black tea, weight gain, and mammary gland tumorigenesis (Rogers, et al, 1998, Carcinogenesis 19, 1269-1273) have been analyzed. Using adjustment of carcinogenesis endpoints for body weight, tumor burden, and latency, they were found to be related to weight gain within treatment groups in 2 of 3 experiments.   相似文献   
52.
53.
Meniscal injuries: detection using MR imaging   总被引:15,自引:0,他引:15  
Both retrospective and blinded analyses of thin-section, high-resolution magnetic resonance (MR) images of the knee joint, produced using a solenoid surface coil, indicate that MR imaging is an effective technique for evaluating meniscal injuries. Images of 49 patients were evaluated, and the results were correlated with those of subsequent arthroscopy. A grading scale was developed to rate the index of suspicion of a meniscal tear based on the MR images. Overall, approximately 80% of menisci rated grade 4 (definite tear) or 3 (probable tear) were found to have corresponding tears at arthroscopy. In many other patients with a grade 4 or 3 meniscus in whom a corresponding tear was not found arthroscopically, meniscal tears at other sites or other abnormalities were correctly diagnosed using MR. A majority of the false-positive MR images involved the posterior horns of the menisci, the sites of most false-negative arthroscopic diagnoses. The predictive value of a negative MR image was almost 100%. Even in patients with moderate-to-large effusions, the menisci were accurately evaluated. The results imply that MR imaging is useful in the preoperative evaluation of suspected meniscal tears.  相似文献   
54.
Chlorpropamide-induced pure white cell aplasia   总被引:2,自引:0,他引:2  
Levitt  LJ 《Blood》1987,69(2):394-400
We investigated the mechanism for isolated agranulocytosis and marrow pure white cell aplasia in an elderly man receiving 0.5 to 1.0 g per day of chlorpropamide (Chl) without other toxic drug exposure or overt systemic illness. Patient marrow revealed an absence of recognizable granulocytic precursors; megakaryocytes and erythroid precursors were normal. The WBC count was 1800/mm3 on admission with only 2% neutrophils; the absolute neutrophil count first exceeded 500/mm3 on the 17th day following cessation of Chl. A serum Chl level on admission was 100 micrograms/mL (acute phase, AP); no Chl was detected in serum (convalescent phase, CP) assessed on the 22nd hospital day. Antineutrophil antibodies were not detected, and T cell depletion failed to augment patient in vitro granulopoiesis. Patient AP serum produced potent complement-mediated inhibition (87% +/- 7%) of autologous granulocyte progenitors (CFU-GM) with minimal inhibition of erythroid (11% +/- 5%) or multipotent (5% +/- 4%) progenitor cells. Selective inhibition by patient AP serum of CFU-GM (74% +/- 11%) was also seen against two allogeneic marrows. Patient CP serum no longer inhibited (6% +/- 4%) autologous CFU-GM. Addition of Chl (5 to 120 micrograms/mL) to CP serum but not to control serum resulted in potent drug concentration-dependent complement-mediated inhibition of autologous and allogeneic CFU-GM. Inhibition of CFU-GM in the presence of Chl was no longer demonstrable following immunoabsorbent removal of IgG from patient serum. Patient serum in the presence of Chl had limited activity against morphologically recognizable marrow granulocytic precursors in a microimmunofluorescence assay. These results are most consistent with the development of Chl-dependent, selective antibody-mediated immune inhibition of granulopoiesis.  相似文献   
55.
Various possible risk factors for postlumbar puncture (and postiohexol-myelographic) headache and associated side effects were analysed. Headache and nausea occurred significantly more often in patients without clinical findings than in those with findings. We found significantly different incidences of severe headache and nausea between diagnostic subgroups after a lumbar puncture. The greatest headache incidence was found in patients without a definite neurological diagnosis, while nausea occurred most frequently in patients with various painful disorders. Following iohexol myelography, nausea occurred most often in patients who had a history of previous mental symptoms and in patients with a history of previous headache disorders. Mental symptoms were more frequently reported in patients who also had experienced mental symptoms previously. The relationship between side effects and negative clinical findings was stronger than the relationship between side effects and previous mental symptoms.  相似文献   
56.
对人流感病毒A/Udorn/72(H_3N_2)株与禽类流感病毒A/Mallard/NY/78/(H_2N_2)重组后的重组株分析表明,仅含禽类病毒的核蛋白(NP)或膜蛋白(M)的RNA片段的重组株,在松鼠猴的呼吸道繁殖是受限制的。另外。仅有禽类的RNAl和NS基因的重组株(Clone 12)在松鼠猴的气管内的繁殖也明显受限制,而只具有其中一个基因的Clone 9, Clone 2, 则限制就不明显。由此表明,禽类流感病毒的NP和M基因在宿主范围的繁殖限制中起主要作用,而RNAI和SN基因的结合,同样起着繁殖受限制作用。  相似文献   
57.
Direct sagittal computed tomographic scanning (DSCT) of the shoulder was performed in 42 symptomatic patients, six healthy volunteers, and two cadaver shoulders. Axial CT scanning and double-contrast arthrography with plain radiographs were performed in 41 patients for comparison. DSCT enabled correct identification of 27 of 29 lesions in 24 patients. Seventeen patients had normal shoulders. Axial CT scanning and DSCT together enabled correct identification of all lesions and were markedly superior to plain-film arthrography. DSCT enabled diagnosis of all cases of complete rotator cuff tear plus three cases of incomplete tear and three of rotator cuff atrophy not identified by the other techniques. Axial CT scanning was better than DSCT for diagnosis of Bankart lesions.  相似文献   
58.
BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies.  相似文献   
59.
目的:分析普通男大学生髋、膝、踝、肩、肘各关节相对峰力矩与蹲跳高度的相关性。方法:实验于2004-11/2005-01在河北省体科所完成。①实验对象:随机抽取河北省某大学普通男生30名,年龄(21.8±0.8)岁,身高(170.67±5.48)cm,体质量(65.70±7.99)kg,测试前均从未进行过专门的肌肉力量训练,优势上、下肢均为右侧。②实验方法:从站立开始加摆臂的反向蹲跳,要求受试者上体尽可能保持前后方向稳定,从站立位开始下蹲时上肢向下加速摆臂,并迅速向上蹬伸起跳。从站立开始不加摆臂的反向蹲跳,是排除上肢对蹲跳高度的影响。从半蹲开始加摆臂的无反向蹲跳,要求半蹲的角度控制在105°,静止状态下半蹲预备后,直接进入向上的蹬伸起跳过程,不能出现在起动瞬间身体重心先小幅下移再向上的情况。每种动作做3次,每次间隔10min。③实验评估:通过爱捷图像解析系统得出蹲跳高度,取成绩最好的一次采用Biodex Ⅱ型等速测力及康复系统检测受试者各关节肌力相对峰力矩。利用多因素优势分析法得出在慢速[60(°、快速[240(°)/s])/s]状态下,髋、膝、踝、肩、肘关节相对峰力矩与蹲跳高度的相关性。结果:①从站立开始加摆臂的反向蹲跳高度与各关节相对峰力矩的关系:在慢速状态时与髋关节伸肌相对峰力矩、踝关节背屈肌相对峰力矩、膝关节伸肌相对峰力矩呈明显相关(r=0.808,0.692,0.656),在快速状态时与肘关节屈肌相对峰力矩呈明显相关(r=0.770)。②从站立开始不加摆臂的反向蹲跳高度与各关节相对峰力矩的关系:在慢速状态时与踝关节背屈肌相对峰力矩呈明显相关(=0.747),在快速状态时与膝关节屈肌相对峰力矩呈明显相关(r=0.796)。③从半蹲开始加摆臂的无反向蹲跳高r度与各关节相对峰力矩的关系:从半蹲开始加摆臂的无反向蹲跳高度,在慢速状态时与髋关节伸肌相对峰力矩、踝关节背屈肌相对峰力矩、膝关节伸肌相对峰力矩呈明显相关(r=0.774,0.762,0.712),在快速状态时与肘关节屈肌相对峰力矩呈明显相关(r=0.843)。结论:①加摆臂的反向与无反向蹲跳,髋关节伸肌相对峰力矩、肘关节屈肌相对峰力矩分别是慢速、快速状态下影响其高度的首要因素。②不加摆臂的反向蹲跳,踝关节背屈肌相对峰力矩、髋关节伸肌相对峰力矩分别是慢速、快速状态下影响其高度的首要因素。③提示发展上肢肌肉力量对蹲跳高度的提高大有益处。  相似文献   
60.
Persistent postmastectomy pain is quite common and has been classified into several distinct types. Few studies, however, have investigated either the predictors or functional impact of multiple types of post mastectomy pain. In this investigation, 278 women, who were, on average, several years post mastectomy, completed questionnaires assessing pain, pain-related physical function, and psychosocial distress. We assessed three distinct categories of postmastectomy pain: phantom breast pain, scar pain, and other mastectomy-related pain. Each of the three types of postmastectomy pain was strongly related to one another (i.e., women reporting one type of pain were more likely to report the other types as well). In general, the more types of postmastectomy pain a woman reported, the greater the degree of disability and distress. Collectively, the presence of “other mastectomy-related pain” was a stronger unique predictor of disability and distress than were the other two categories of pain. Interestingly, demographic and surgical factors, including time since surgery, were not consistent predictors of pain or function. The findings suggest that the assessment of postmastectomy pain should include formal evaluation of multiple types of pain, with additional attention paid to the category of “other mastectomy-related pains,” and that the number of types of pain reported by women after surgery may be important in predicting functional outcomes.  相似文献   
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