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61.
The trafficking or homing of different lymphoid subsets to particular microenvironment is mediated by specific cell adhesion molecules (CAMs) expressed on lymphocytes and endothelial cells. B-cell chronic lymphocytic leukaemia (B-CLL) or Non-Hodgkin's lymphoma of small lymphocytic, B-cell type are monoclonal expansions of mature lymphocytes. The relative distribution of the tumor lymphocytes among various lymphoid compartments vary from patient to patient. Very few studies underlying this issue are available. To this effect, we have analysed the expression of LFA-1; VLA-4, ICAM-1; CD44H and CD44v6 (haematopoietic and variant form respectively) on freshly isolated lymphocytes obtained from bone marrow (BM), peripheral blood (PB) and lymph node (LN) by flow cytometry. Overall, we find strong expression of CD44H, low to moderate expression of LFA-1, negative to low expression of VLA-4 and lack of expression of CD44v6. ICAM-1 expression was observed only in patients with prominent lymphadenopathy. Higher expression of CD44H in PB lymphoid cells relative to that of BM lymphoid cells correlated with higher PB lymphocytosis (p < 0.001). Proliferating cell nuclear antigen expression in LN sections correlated inversely with VLA-4 expression on BM and PB lymphoid cells (p < 0.05). There was no significant correlation between expression of CAMs and bcl-2 protein.  相似文献   
62.
This unusual cystic lesion was previously described as a lesion that has features of both botryoid odontogenic cyst and mucoepidermoid tumor and later was named as glandular odontogenic cyst. An additional case is reported and its clinicopathologic features described. The name "mucoepidermoid odontogenic cyst" is proposed.  相似文献   
63.
OBJECTIVE: Antenatal steroids result in fetal lung maturation, but may retard brain development. Auditory brainstem-evoked response (ABR) is a noninvasive assessment of brainstem maturation. The objective of this study was to determine if antenatal steroids affect brainstem maturation in infants 相似文献   
64.
Amirjamshidi A  Abbassioun K  Sadeghi Tary A 《Surgical neurology》2000,54(2):178-81; discussion 181-2
BACKGROUND: Growing skull fractures rarely develop in the skull base region. To the best of our knowledge, only two similar cases have been reported in the English literature. This rare complication, which can occur even after a mild head injury, can produce exophthalmos and threaten the vision. METHODS: The clinical and radiological findings of expanding leptomeningeal cysts extending into the orbit in nine patients referred to the department of Neurosurgery are presented. After appropriate investigations confirming the presence of the expansile retroglobal lesion, surgical exploration was performed via fronto-lateral or the preferred fronto-basal approach. The variable findings are denoted and the relevant literature is also reviewed. RESULTS: Frontobasal head injuries play an important role in pathogenesis of these traumatic expansile leptomeningeal cysts. In this series of nine young girls, 6.65% (six out of nine) injuries happened in the first decade of life with an interval of 2 to 12 months (mean = 6.7, SD = 9.7). High-resolution coronal view computed tomography (CT) scanning with bone density window images, and high intensity cystic lesions visible on T2-weighted coronal MR images were diagnostic clues. CONCLUSIONS: Growing fractures of the anterior skull base may complicate the natural course of healing of any minor frontobasal head injury, especially during childhood. Good quality imaging is mandatory in cases of progressive unilateral exophthalmos. Proper surgical intervention will lead to a good cosmetic result.  相似文献   
65.
Accurate pathologic staging of carcinomas of the urinary bladder involves assessment of invasion by the tumor into the bladder wall and beyond into perivesical soft tissue. The presence of tumor within perivesical soft tissue implies pathologic stage pT3 (AJCC/UICC system, 1997). In traditional textbooks of histology, anatomy, pathology, and in the literature, other than a single case report and a brief reference in another paper, there is no information on the presence of adipose tissue in the lamina propria or muscularis propria of the urinary bladder. Nine hundred forty-three sections from 139 cystectomy specimens were evaluated for the presence, location, and quantity of adipose tissue within the lamina propria and muscularis propria. The histology of the perivesical soft tissues and the nature of its delineation from muscularis propria were also analyzed. Adipose tissue was seen within the lamina propria in 53% (74 of 139) of cystectomies and in 17.6% (166 of 943) of the examined sections. It was located predominantly in the deep lamina propria (at or below the muscularis mucosae) in 81.1% (60 of 74) of the cystectomies and in 91% (151 of 166) of the sections. Within the lamina propria it was predominantly seen as small localized aggregates in 92% (153 of 166) of sections. All cases showed adipose tissue within the muscularis propria. Adipose tissue was identified within the superficial (inner) muscularis propria in 54% (512 of 943) of sections and was predominantly in small aggregates in 80.5% (412 of 512) of sections. It was in moderate to abundant quantities within the deep (outer) muscularis propria in 60.7% (572 of 943) of sections. The perivesical soft tissue was almost exclusively composed of adipose tissue with variable vascularity. Delineation of the perivesical adipose tissue from the deep (outer) muscularis propria was typically indistinct because muscle bundles of the latter haphazardly merged with the perivesical adipose tissue. Based on these findings, we conclude that adipose tissue is frequently present in the lamina propria and muscularis propria of the urinary bladder wall, and is usually scant in the former location and frequently abundant in the latter. Awareness of the high frequency of adipose tissue within the urinary bladder wall has prognostic and therapeutic implications. In transurethral resection of bladder tumor (TURBT) specimens, misinterpretation of tumor infiltrating adipose tissue within lamina propria (pT1) as perivesical soft tissue involvement (pT3) may potentially result in unwarranted aggressive management. Substaging of muscle invasive tumors should be performed in cystectomy specimens only, because the junction of muscularis propria and the perivesical adipose tissue is typically ill-defined. Muscularis propria adipose tissue in TURBT specimens may be erroneously assumed to be perivesical adipose tissue, potentially leading to overstaging of the primary tumor.  相似文献   
66.
Hecht  SS; Ronai  ZA; Dolan  L; Desai  D; Amin  S 《Carcinogenesis》1998,19(1):157-160
We compared the tumor-initiating activities toward mouse skin of two structurally related polycyclic aromatic hydrocarbon diol epoxides: racemic anti-1,2,3,4-tetrahydro-5,6-dimethylchrysene-1,2-diol-3,4- epoxide (5,6-diMeCDE) and racemic anti-1,2,3,4-tetrahydro-5- methylchrysene-1,2-diol-3,4-epoxide (5-MeCDE). Tumors induced by these diol epoxides were analysed for mutations in the Ha-ras gene. 5,6- diMeCDE is derived from the non-planar parent compound 5,6- dimethylchrysene, and reacts to approximately equal extents with dA and dG in DNA, whereas 5-MeCDE is derived from a nearly planar parent compound, 5-methylchrysene, and reacts mainly with dG in DNA. 5,6- diMeCDE, at initiating doses of 33, 100 or 400 nmol per mouse, induced 1.2, 2.2 and 6.2 skin tumors per mouse, respectively. It was significantly less tumorigenic than 5-MeCDE which induced 3.1, 7.5 and 9.1 skin tumors per mouse at the same doses. Tumors induced by 5,6- diMeCDE had a large number of CAA-->CTA mutations in codon 61 of the Ha- ras gene: 50, 55 and 75% of the tumors analysed had this mutation at the 33, 100 and 400 nmol doses. No mutations were found in codons 12 and 13 in the tumors induced by 5,6-diMeCDE. In contrast, CAA-->CTA mutations in codon 61 were rarely seen in tumors induced by 5-MeCDE. At the highest dose of 5-MeCDE, 20% of the tumors analysed had mutations at G of codons 12 and 13. The results of this comparative study support the hypothesis that mutations in the Ha-ras gene in mouse skin tumors induced by PAH diol epoxides occur as a result of their direct reaction with the gene. However, pathways other than the commonly observed Ha- ras codon 61 mutations are clearly important in mouse skin tumorigenesis by these diol epoxides.   相似文献   
67.
Timing in peak gait values shifts slightly between gait trials. When averaged, the standard deviation (S.D.) in gait data may increase due to this inter-trial variability unless normalization is carried out beforehand. The objective of this study was to determine how curve registration, an alignment technique, can reduce inter-subject variability in gait data without perturbing the curve characteristics. Twenty young, healthy men participated in this study each providing a single gait trial. Gait was assessed by means of a four-camera high-speed video system synchronized to a force plate. A rigid body three-segment model was used in an inverse dynamic approach to calculate three-dimensional muscle powers at the hip, knee and ankle. Curve registration was applied to each of the 20 gait trials to align the peak powers. The mean registered peak powers increased by an average of 0.10±0.13 W/kg with the highest increases in the sagittal plane at push-off. After performing curve registration, the RMS values decreased by 13.6% and the greatest reduction occurred at the hip and knee, both in the sagittal plane. No important discontinuities were reported in the first and second derivatives of the unregistered and registered curves. Curve registration did not have much effect on the harmonic content. This would be an appropriate technique for application prior to any statistical analysis using able-bodied gait patterns.  相似文献   
68.
PURPOSE: Erythropoietin, an oxygen-regulated glycoprotein hormone, is a hematopoietic cytokine that stimulates erythropoiesis by binding to its cellular receptor [erythropoietin receptor (EPOR)]. The recombinant form of human erythropoietin is used to prevent or treat anemia in cancer patients. However, in a recent randomized, placebo-controlled trial involving patients receiving curative radiotherapy for squamous cell carcinoma of the head and neck, erythropoietin treatment was associated with poorer locoregional progression-free survival. The purpose of our study was to determine whether EPOR and its ligand erythropoietin are expressed in primary head and neck cancer. We also investigated the hypothesis that erythropoietin expression in malignant cells may be associated with the presence of tumor hypoxia, an important factor involved in resistance to radiation treatment, tumor aggressiveness, and poor prognosis. EXPERIMENTAL DESIGN: Twenty-one patients received an i.v. infusion of the hypoxia marker pimonidazole hydrochloride before multiple tumor biopsies. Contiguous sections from 74 biopsies were analyzed by immunohistochemistry for EPOR and erythropoietin expression and pimonidazole binding. RESULTS: EPOR expression was present in tumor cells in 97% of the biopsies. Coexpression of erythropoietin was observed in 90% of biopsies. Erythropoietin and pimonidazole adduct staining did not always colocalize within tumors, but there was a significant positive correlation between levels of microregional erythropoietin expression and pimonidazole binding. CONCLUSIONS: The coexpression of erythropoietin and EPOR in tumor cells suggests that erythropoietin may potentially function as an autocrine or paracrine factor in head and neck cancer. The expression of the hypoxia-inducible protein erythropoietin in tumor cells correlates with levels of tumor hypoxia.  相似文献   
69.
王瑞凯  李阿敏  刘家昌 《西部医学》2019,31(12):1892-1896
目的 对慢性阻塞性肺疾病患者(COPD))一般资料及临床资料进行主成分分析和判别分析,研究影响疾病急性加重频率的因素,以预测患者后续发病频率。 方法 选取我院2016年1月~2017年10月收治的350例COPD患者为研究对象,收集患者例入院时一般资料、24h内动脉血气分析,首次降钙素原(PCT)含量、C反应蛋白(CRP)含量及血常规,及入院结束治疗时的抗生素治疗时间、住院时间。对入选患者随访1年,并明确1年内慢性阻塞性肺疾病急性加重(AECOPD)次数,根据疾病加重次数将患者分为三组(A组:≤1次;B组:<3次;C组:≥3次)。比较三组一般资料及临床资料的差异,利用因子分析提取上述临床指标及一般资料主成分,并利用主成分对AECOPD患者急性加重频数行判别分析,比较提取主成分前后判别分析率差异。结果 共纳入患者321例,其中A组105例、B组105例、C组111例,三组一般资料及临床资料除吸烟年无明显差异,其余指标组间比较,差异有统计学意义(P<0.05)。从临床指标及一般资料中共提取5个主成分,综合信息提取率833%。一般资料及临床指标判别分析提示,总体判别正确率为748%,A、B、C组三组正确判别率分别为88.6%、65.7%、70.3%;利用提取的主成分进行判别分析提示,总体判别正确率72.0%,A、B、C组三组正确判别率分别为971%、60%、595%。结论 利用常见一般资料及临床资料进行判别分析,可预测患者发病频数,主成分分析的判别正确率与综合资料判别正确率间无明显差异。  相似文献   
70.
The World Health Organization has recommended the integration of Complementary and Alternative Medicine (CAM) with modern medicine, as part of the global “health for all” approach. Herbal treatments are the most common and known methods of CAM. Based on the critical role of physicians in true and safe application of these products, this research evaluated knowledge, attitude, and practice (KAP) of physicians in Rasht towards herbal remedies. This was a cross sectional study, performed between April 2017 and May 2019 on all physicians, who worked in Rasht city, northern Iran. A researcher-made questionnaire with 2 main parts, including a demographics section and research questions was used. A total of 142 (38%) individuals responded to the questionnaires. Mean KAP scores were 6.47 ± 6.17, 27.80 ± 3.26, and 5.02 ± 5.54, respectively. In none of these fields, significant differences were seen in participants regarding demographic variables, experience, work place, academic relevance, and field of work (P > .05). Physicians of Rasht city, with different work environments and regardless of demographic characteristics, had a positive view towards herbal remedies, without enough knowledge to consult their patients.  相似文献   
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