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961.
A case of an infant with an asymmetrical head is presented. On clinical assessment the patient displayed features of deformational plagiocephaly. With the aid of three‐dimensional CT imaging of the skull, a bipartite parietal bone was diagnosed. The prevalence and possible aetiology of a bipartite parietal bone is discussed as well as a brief overview of the common causes of plagiocephaly.  相似文献   
962.
PURPOSE: To assess tolerance and efficacy of preoperative treatment with uracil/tegafur and radiotherapy (RT) followed by surgery and postoperative flurouracil (FU)/leucovorin (LV) in patients with rectal cancer. PATIENTS AND METHODS: Patients (n = 94) with potentially resectable tumors, ultrasound at stages T2N+ (n = 4), T3 (n = 77), T4 (n = 13) were treated with UFT (400 mg/m2/d, 5 days a week for 5 weeks) and concomitant RT to the pelvis (45 Gy; 1.8 Gy/d over 5 weeks). Patients underwent surgery 5 to 6 weeks later followed by four cycles of FU/LV. Primary end points included downstaging, pathologic responses, and sphincter-preserving surgery. Secondary end points were recurrence-free survival and overall survival. RESULTS: All patients received the full RT dose. Fifteen patients (16%) needed UFT dose reduction. Preoperative G3+ toxicities included diarrhea (14%), leukopenia (1%), thrombocytopenia (1%), and nausea (4%). The downstaging rate was 54%, pathologic complete response (pCR) was 9% and, in an additional 23%, there were only residual microscopic foci. When cellular viability criteria were taken into account, the pCR was 15%. From 43 patients with abdominoperineal resection indication, 11 (25%) had sphincter-preserving surgery performed. Postoperative scheduled chemotherapy dose was not administered to 24% of patients because of G3+ toxicity (diarrhea, 8%; mucositis, 9%; and leukopenia, 7%). Patients with downstaging had significantly higher survival and recurrence-free survival rates than those without. At 3 years, actuarial patterns of failure were pelvic, 5% and distant, 11%. OS was 75%. CONCLUSION: UFT combined with RT is safe and effective. In resectable rectal cancer, if preoperative treatment is considered, this approach can be an option.  相似文献   
963.
BACKGROUND AND PURPOSE: Modern conformal radiotherapy treatments require accurate dose calculation in any relevant clinical situation. One of these situations is the treatment of lung tumors, where irradiation has to be planned under challenging conditions for dose calculation. In this study we assess the errors in dose values predicted by fast Fourier transform convolution (FFTC) and multigrid superposition (MGS) algorithms implemented in a commercial treatment planning system (TPS). MATERIALS AND METHODS: FFTC and MGS algorithms were used in a FOCUS 3.0.0 (Computerized Medical Systems, USA) to calculate doses in treatment plans using photon beams of 6 and 25 MV nominal energy from a Saturne 43 linac (GE Medical Systems, USA). A 10x10-cm beam irradiating a mediastinum-lung and a thoracic wall-lung-thoracic wall modeled geometry was assessed. The calculated data were compared with measurements performed with radiographic films and ionization chamber. RESULTS: FFTC algorithm leads to an average deviation from ionometric dose measurements of over 10%. Discrepancies between measured and calculated beam fringe values (distance between 50 and 90% isodose lines) of up to 8 mm were observed. For MGS algorithm, all the points assessed in both geometries fulfilled the 3%-3 mm accuracy criteria and the average deviation of absolute dose was about 1%. A maximum of 3 mm deviation in the beam fringe for any depth was found and was within 2 mm beyond the buildup region. Deviations between ionometric and film measurements were within 3%. CONCLUSIONS: MGS algorithm assesses with reasonable accuracy dose distributions and absolute dose in inhomogeneous regions like the lung region. Therefore, and respecting the inhomogeneity dose calculation, the system could be used in routine clinical practice and in dose-escalation programs. This is not true in the case of FFTC algorithm which leads to errors greater than 10% in the absolute dose calculation and underestimates the beam fringe by up to 8 mm.  相似文献   
964.
p27~(kip1)蛋白在宫颈癌组织中的表达及其意义   总被引:1,自引:0,他引:1  
目的 :探讨细胞周期依赖性激酶抑制剂 p2 7kip1与宫颈癌发生、发展、转移及预后的关系。方法 :采用免疫组织化学方法检测 86例宫颈癌、2 5例宫颈非典型增生、2 4例正常宫颈组织中p2 7kip1 表达情况。结果 :p2 7kip1 在宫颈正常组织中均呈阳性表达 ,其中强阳性率 87.5 %明显高于宫颈非典型增生或宫颈癌组织中的强阳性率 (2 8% ) (P<0 .0 1) ;宫颈癌临床 0期、 a 期~ b 期、 a~ b 期的强阳性率分别 5 2 %、2 5 %、2 1% ,0期与 期、 期之间差异有显著性 (P<0 .0 5 ) ;病理分化程度高 (G1 )、中 (G2 )、低 (G3)者的强阳性率分别为 5 2 %、2 9%、4 % ,分别比较差异均有显著性 (P<0 .0 5 ) ;有无淋巴结转移者的强阳性表达分别为 36 %、8% ,两者差异有显著性 (P<0 .0 1) ;p2 7kip1表达强阳性者 3年和 5年生存率分别为 91%和 85 % ,显著高于低表达者的 6 7%和 5 1% (P<0 .0 5 )。结论 :p2 7kip1蛋白表达的下降可能与宫颈癌发生、发展、转移有关 ,p2 7kip1可能成为反映肿瘤恶性表型的指标 ,对宫颈癌预后具有一定的参考价值。  相似文献   
965.
Background. To know the temporary tendency in the mortality due to breast cancer in Castilla-La Mancha (CLM, Spain) between 1975 and 1998. Patients and methods. The mortality data are from the Registry of Mortality of CLM. Crude and standardized mortality rates are calculated. In order to evaluate the tendency, we use the Poisson’s log- linear model. We have calculated the accumulated rate to die and the accumulated risks to die and to become ill. Results. Between 1975 and 1998, 2.44% of all deaths in CLM women were consequence of a breast cancer. The crude rate increased from the 14.55 by 100,000 in 1975 to 25.23 by 100,000 in 1998, with an annual average increase of 1.49%. The average age of death increased until the 67 years old in 1998 as opposed to the 59 years old of 1975. The risk of dying of a breast cancer increased in the period from 1.4% in 1975 to 2.34% in 1998. Conclusion. Mortality by breast cancer has raised until 1993, when it begun to decrease. In general, women with breast cancer die elderly, and young women have increased risk to fall ill.  相似文献   
966.
967.
目的: 建立人单核巨噬细胞泡沫化抑制剂筛选模型,筛选得到可抑制细胞泡沫化的抑制剂.方法: U937单核细胞经100 nmol·L-1佛波酯(PMA)诱导72 h分化为巨噬细胞后,换无血清培养液于96孔板中,每毫升含巨噬细胞1×106个,每孔再加入80 mg·L-1氧化的低密度脂蛋白(ox-LDL),37 ℃培养48 h,建立单核巨噬细胞泡沫化模型.利用微生物发酵液,或单一的化合物样品与其共孵育,油红.染色后观察细胞胞内变化,寻找对泡沫细胞形成有抑制作用的样品.利用基因工程技术表达的人清道夫受体A类II型的胞外部分,在本模型中可抑制巨噬细胞泡沫化的形成,进一步验证了模型的可行性.结果: 从2000 个微生物发酵液中筛选到6株微生物发酵液为阳性,从10个化合物中发现一个有抑制巨噬细胞泡沫化活性的新化合物.结论: 本模型可用于细胞泡沫化抑制剂的高通量筛选.  相似文献   
968.
宫颈癌微血管计数和血管内皮生长因子的表达   总被引:4,自引:0,他引:4  
目的探讨微血管密度(MVD)和血管内皮生长因子(VEGF)表达与宫颈癌的临床病理联系及其相互关系。方法应用免疫组织化学方法检测和分析72例宫颈癌、24例正常宫颈组织中MVD和VEGF的表达情况。结果宫颈癌患者的微血管密度明显高于正常组织(P<0.01);宫颈浸润癌明显高于原位癌(P<0.01),浸润癌Ⅰ期与Ⅱ期差异无显著性(P>0.05);MVD随着病理分级增高呈递增趋势,组织学分级Ⅰ级与Ⅱ级、Ⅲ级差异有显著性(P<0.05);MVD增高与患者的生存期有关,生存期<5年者MVD明显高于生存期>5年者(P<0.05);MVD与临床分型、淋巴结转移无明显相关性(P>0.05)。VEGF在宫颈原位癌呈低表达,原位癌强阳性率明显低于浸润癌(P<0.05);VEGF表达强弱与病理组织学分级有关,分化程度低,恶性程度高,VEGF表达增强。VEGF表达阳性组的宫颈癌标本中MVD明显高于VEGF表达阴性组(P<0.05),且随着VEGF表达的增强,微血管密度随之增加,两者呈正相关。结论VEGF与宫颈癌的血管生成密切相关;MVD和VEGF表达与宫颈癌的恶性程度密切相关。  相似文献   
969.
A retrospective analysis was performed of 50 patients with adenoid cystic carcinoma who were seen in the Department of Radiation Oncology, University of Witwatersrand, Johannesburg, South Africa, in the past 10 years. There were 25 men and 25 women with a mean age of 52 years (age range, 21 to 88 years). Five patients had metastatic disease, and 17 had neural invasion. Thirty-four patients had surgery (11, complete; 23, microscopic residual). Sixteen patients had radiotherapy as initial management. The disease-free survival was 26%, overall survival was 29%, and local control was 30% at 10 years. Most recurrences occurred in the first 3 years. Nine patients had metastasis following treatment. The mean survival after metastasis was 15 months. Seven prognostic variables were analyzed using the log-rank test. There was no impact of age, site, type of salivary gland (major vs. minor), tumor stage, node positivity, or neural invasion on disease-free survival, overall survival, or local control. Extent of surgical resection (complete vs. microscopic residual) had a significant impact on disease-free survival and local control (P < 0.05) but no impact on overall survival (P > 0.05) because of the slow-growing nature of these tumors. Similarly, patients who had microscopic residual after surgery and were treated with radiotherapy did better than those who had biopsy and radiotherapy, although this was not significant statistically (P > 0.05). Thus, whenever possible, every attempt must be made to remove all microscopic tumor by surgery. Addition of postoperative radiotherapy with high-energy photons did not improve the locoregional control or survival in our series. There is a place for neutrons in the treatment of adenoid cystic carcinomas in advanced cases of inoperable or recurrent tumors, as a review of literature shows.  相似文献   
970.
Purpose: Our purpose was to assess the endocrine status of women with polycystic ovaries (PCO) undergoing IVF, and to compare oocyte quality with endocrine markers of the syndrome, in an attempt to define a subpopulation with poor quality oocytes. Methods: This was a retrospective study. Patients were first endocrinologically analyzed: serum levels of androgens (T, androstenedione, DHEAS), FSH, and LH as well as glucose and insulin after an oral glucose tolerance test (OGTT) were recorded and are expressed as absolute values and area under the curve (AUC). Subsequently, they were followed over a 2-year period in which patients underwent several attempts of IVF as well as serving as oocyte donors. Patients were divided into three groups: group I (n=4) was women who displayed embryos unable to implant in 15 IVF cycles and 10 ovum donation cycles in which they served as donors; group II (n=16) was PCO patients in whom IVF (n=38) and/or oocyte donation cycles (n=42) resulted in pregnancies; and group III (n=13) was IVF patients with normal appearance of the ovaries by ultrasound. The endocrine status was compared with the IVF results. Results: There was no difference among groups in the endocrinological parameters tested, except for the OGTT which identified women in group I as having higher serum glucose and insulin levels than patients in groups II and III. Similarly, the OGTT showed higher serum glucose values in group II compared to group III. Women in group I were also obese. Patients in group III were older than PCO patients and needed more gonadotropins to reach an ovarian response which resulted in a reduced number of oocytes retrieved. Fertilization was also impaired in group I, in which no pregnancy was recorded. Conclusions: This study shows that there is a particular subgroup of PCO patients with lower fertilization rates and embryos unable to implant. These patients are obese and nonhyperandrogenic and show derangements of insulin secretion.  相似文献   
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