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101.
Summary Techniques are described for the rapid isolation, monolayer culture, and phenotypical characterization of embryonic Day 12 (E12) rat liver epithelial cells. In vitro assays of the differentiation potential of these cells are currently being performed under conditions that make use of-modified Eagle's medium supplemented with fetal bovine serum, insulin, and dexamethasone with or without sodium butyrate. In the absence of sodium butyrate, the cells differentiate along the hepatocytic cell lineage, whereas in its presence they express the phenotype of the biliary ductal epithelial cell lineage. 相似文献
102.
人嗜铬细胞瘤细胞的原代培养及鉴定 总被引:2,自引:2,他引:2
本研究拟建立人嗜铬细胞瘤细胞的原代培养方法。采用连续分次胶原酶消化法分离培养人嗜铬细胞瘤细胞,采用细胞培养液中儿茶酚胺水平检测、多聚甲醛诱发荧光及细胞嗜铬粒蛋白A(CgA)和神经元特异性烯醇化酶(NSE)的免疫组化染色等方法进行细胞性质和功能鉴定,并用噻唑兰(MTT)法观察原代培养的人嗜铬细胞瘤细胞的生长状况。结果表明,人嗜铬细胞瘤细胞在培养3~7天时生长较快,7天后细胞开始分化。经检测细胞培养液中的儿茶酚胺浓度、多聚甲醛诱发荧光等,证明该细胞有合成和分泌儿茶酚胺的功能。并且培养的细胞CgA和NSE免疫组化染色阳性。因此,本研究成功建立了人嗜铬细胞瘤细胞的原代培养方法,并鉴定其具有嗜铬细胞瘤的分泌和表达功能,国内尚未见报告。 相似文献
103.
Richard D Neal Victoria L Allgar Nasreen Ali Brenda Leese Phil Heywood Gill Proctor Joyce Evans 《The British journal of general practice》2007,57(536):212-219
BACKGROUND: Very few studies have reported cancer outcomes of patients referred through different routes, despite the prominence of current UK cancer urgent referral guidance. AIM: This study aimed to compare outcomes of cancer patients referred through the urgent referral guidance with those who were not, with respect to stage at diagnosis, survival, and delays in diagnosis. Design of study: Analysis of hospital records. SETTING: One hospital trust in England. METHOD: The records of 889 patients diagnosed in 2000-2001 with one of four types of cancer were analysed: 409 with lung cancer; 239 with colorectal cancer; 146 with prostate cancer; and 95 with ovarian cancer. Outcome measures were diagnostic stage, survival, referral and secondary care delays. RESULTS: For lung cancer, urgent referrals had more advanced TNM (tumor, node, metastasis) stage than patients diagnosed through other routes (P = 0.035) and poorer survival (P = 0.020). There was no difference in stage or survival for the other cancers. For each cancer, a higher proportion of urgent referrals was seen within 2 weeks. Secondary care delays for lung and colorectal cancer were shorter for inter-specialty referrals. CONCLUSION: For patients with lung cancer, the guidance appears to be prioritising those in the more advanced stages of disease. This was not the case for the other three cancers. Referral delays were shorter for patients urgently referred, as is the intention of the guidance. The avoidance of delays in outpatient diagnostics probably accounts for shorter secondary care delays for inter-specialty referrals. 相似文献
104.
Liang Shan Yasushi Nakamura Misa Nakamura Toyoharu Yokoi Kennichi Kakudo 《Pathology international》1998,48(8):569-574
Hyperparathyroidism refers to a term representing a wide spectrum of parathyroid disorders that are characterized by the increased production of parathyroid hormone. Hyperparathyroidism was once thought to be tare but is now more commonly recognized, aifecting 1 in 500 women over 40 years of age. Yet the interpretation of parathyroid pathology is still controversial and confusing. Over the past 10 years, genetic changes ( ret and menin genes) involved in the pathogenesis of MEN 2 and MEN 1 have been discovered in succession. Different mutations of the calcium-sensing receptor gene have been identified in neonatal severe hyperparathyroidism and familial hypocalciuric hypercal-cemia, respectively. The HRPT 2 gene responsible for the development of heredltaty hyperparathyroidism and jaw tumors has been localized on the 1q21–31 locus. Several genetic alterations have also been characterized in primary and secondary hyperparathyroidism. Different genetic alterations appear to involve the development of different types of hyperparathyroidism. These novel advances give us new insights into the pathogenesis of hyperparathyroidism and allow better differentiation between the different types of parathyroid disorders. 相似文献
105.
目的探讨人肝癌细胞系HepG2经5-氮杂-2’-脱氧胞苷(5-Aza-2-’deoxycytid ine,5-Aza-CdR)处理后诱导高甲基化失活的RUNX3基因重新表达的可能性及对细胞生长的影响,寻找抗癌治疗的新靶点。方法RT-PCR检测抑癌基因RUNX3 mRNA的表达;MTT、集落形成实验观察细胞的生长活性;流式细胞术和透射电镜分析细胞周期及细胞凋亡的变化。结果肝癌细胞经不同浓度之5-Aza-CdR处理后,原无RUNX3 mRNA表达的细胞均检出基因重新表达,细胞生长速度出现不同程度减慢及细胞克隆形成率显著降低(P<0.01)。用药后肝癌细胞发生明显的S期阻滞,电镜显示肝癌细胞形态学改变。结论去甲基化制剂5-Aza-CdR能有效地激活肝癌细胞系HepG2因高甲基化所致RUNX3基因沉默的再转录,诱导该基因的表达,从而抑制肿瘤细胞生长。 相似文献
106.
Primary non-Hodgkin's lymphoma of the intestine: a morphological, immunohistochemical and clinical study of 31 Chinese cases 总被引:5,自引:0,他引:5
Thirty-one cases of primary non-Hodgkin's lymphoma of the intestine were investigated. Twenty-one were of B-cell and 10 of T-cell origin. The B-cell lymphomas comprised two cases of low-grade B-cell lymphoma of mucosaassociated lymphoid tissue (MALT), one of centroblastic/centrocytic type, three of high-grade B-cell lymphoma coexisting with a low-grade B-cell lymphoma of MALT, nine of centroblastic, three of immunoblastic and three of Burkitt type. Of the T-cell lymphomas, eight were of pleomorphic medium-to large-sized cell type and two of large cell anaplastic type. All the B-cell lymphomas expressed CD20 (L26) and/or Ki-B5; in six there was monotypic immunoglobulin light chain restriction. Membrane positivity for CD45RO (UCHL1) was observed in the 10 cases of T-cell lymphoma, but the tumour cells did not express monocyte-macrophage markers. Clinically, the patients with T-cell lymphomas were usually young males with constitutional symptoms and their prognosis was significantly worse than those of patients with intestinal B-cell lymphoma. 相似文献
107.
Elizabeth Dormandy Martin C Gulliford Erin P Reid Katrina Brown Theresa M Marteau 《The British journal of general practice》2008,58(548):154-159
BACKGROUND: Antenatal sickle cell and thalassaemia screening sometimes occurs too late to allow couples a choice regarding termination of affected fetuses. The target gestational age for offering the test in the UK is 10 weeks. AIM: To describe the proportion of women screened before 70 days' (10 weeks') gestation and the delay between pregnancy confirmation in primary care and antenatal sickle cell and thalassaemia screening. DESIGN OF STUDY: Cohort study of reported pregnancies. SETTING: Twenty-five general practices in two UK inner-city primary care trusts offering universal screening. METHOD: Anonymised data on all pregnancies reported to participating general practices was collected for a minimum of 6 months. RESULTS: There were 1441 eligible women intending to proceed with their pregnancies, whose carrier status was not known. The median (interquartile range [IQR]) gestational age at pregnancy confirmation was 7.6 weeks (6.0-10.7 weeks) and 74% presented before 10 weeks. The median gestational age at screening was 15.3 weeks (IQR = 12.6-18.0 weeks), with only 4.4% being screened before 10 weeks. The median delay between pregnancy confirmation and screening was 6.9 weeks (4.7-9.3 weeks) After allowing for practice level variation, there was no association between delay times and maternal age, parity, and ethnic group. CONCLUSION: About 74% of women consulted for pregnancy before 10 weeks' gestation but fewer than 5% of women were screened before the target time of 10 weeks. Reducing the considerable delay between pregnancy confirmation in primary care and antenatal sickle cell and thalassaemia screening requires methods of organising and delivering antenatal care that facilitate earlier screening to be developed and evaluated. 相似文献
108.
109.
The purpose of the present paper was to examine the level of apoptosis and the relationships among apoptosis, apoptosis-associated proteins, and proliferating potential in lymphoma tissues to clarify the characteristics of apoptosis in diffuse large B-cell lymphomas (DLBCL) of the central nervous system (CNS). The formalin-fixed, paraffin-embedded tissues of CNS and non-CNS DLBCL (20 cases each) were studied by terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) and immunohistochemistry, using antibodies against single-stranded DNA (ssDNA), cleaved caspase-3, bcl-2, bax, p53, Fas and Ki-67. The cleaved caspase-3 immunohistochemistry detected apoptosis of the lymphoma cells most sensitively compared to TUNEL and ssDNA immunohistochemistry. High expression (grade + + or + + +) of cleaved caspase-3 was found more frequently in CNS DLBCL (11 cases, 55%) than non-CNS DLBCL (three cases, 15%; P = 0.009). Bax-positivity of lymphoma cells was increased in six cases of CNS DLBCL, which also showed high positivity of cleaved caspase-3. There was no significant correlation between the cleaved caspase-3-positivity and the Ki-67 positivity. The present study indicates that the number of apoptotic cells and expression level of cleaved caspase-3 were significantly higher in CNS DLBCL than non-CNS DLBCL, and that the correlation of bax and cleaved caspase-3 expression was often present in CNS DLBCL. 相似文献
110.
Summary Preparations of 75–80% pure Leydig cells are prepared by Percoll gradient centrifugation of crude testicular interstitial cell suspensions. Using the methods described herein, the purified Leydig cells retain their functional characteristics for at least 72 hours in primary culture. 相似文献