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991.
We report the case of a patient with three synchronous but histologically different primary renal tumors that were all in the same kidney. Two tumors were different subtypes of renal cell carcinoma (RCC), and the third was a variant form of angiomyolipoma. The patient was a 62-year-old man who was receiving antihypertensive drugs and came to our hospital for a regular check-up. Ultrasonography performed during the visit revealed a left renal mass, but the patient had no related symptoms. Subsequent computed tomography revealed two round, high-density masses, one in the mid-portion and the other in the lower pole of the left kidney, and multiple cysts in the right kidney and the liver. The mass in the mid-portion measured 3.3 x 3.0 x 2.8 cm, and the mass in the lower pole measured 1.7 x 1.1 x 0.9 cm. A left radical nephrectomy was performed. On gross examination, an additional ovoid nodule (0.6 cm in the greatest dimension) was found in the lower pole. Microscopically, the largest tumor consisted of a broad alveolar arrangement of large round cells with abundant eosinophilic or clear cytoplasm, distinct cell borders, and perinuclear halos, features consistent with chromophobe RCC. The smallest tumor was a conventional (clear-cell) RCC. The third tumor was composed solely of atypical epithelioid cells with prominent nucleoli and yellowish-brown to black pigments. The tumor cells were positive for melanin (Fontana-Masson stain), the melanoma marker HMB45, vimentin, smooth-muscle actin, and the macrophage marker CD68 and were negative for cytokeratin. This tumor was considered a pigmented epithelioid type of angiomyolipoma. The histologic, histochemical, and immunohistochemical features in this case confirmed the presence of three synchronous primary tumors, a chromophobe and a clear-cell type RCC and a pigmented epithelioid angiomyolipoma, all of which were in the same kidney. This case is the first of its type reported in the literature. 相似文献
992.
VRK1 is a novel human putative serine/threonine kinase, and is located on chromosome 14 at band q32 where an autosomal recessive
congenital microphthalmia (CMIC) is mapped. We isolated a polymorphic dinucleotide CA repeat marker from a genomic clone containing
the human VRK1 gene. This polymorphism will be useful in genetic studies of disorders localized at the 14q32 region, such as CMIC.
Received: October 8, 1998 / Accepted: October 16, 1998 相似文献
993.
Unique properties of fetal lymphoid progenitors identified according to RAG1 gene expression 总被引:3,自引:0,他引:3
Yokota T Kouro T Hirose J Igarashi H Garrett KP Gregory SC Sakaguchi N Owen JJ Kincade PW 《Immunity》2003,19(3):365-375
RAG1/GFP knockin mice were exploited to isolate and characterize fetal lymphoid progenitors. CD11b and IL-7Ralpha are expressed in a developmental stage-dependent fashion, revealing how substantial numbers of early lymphoid progenitors were discarded or neglected in previous studies. The myeloerythroid potential of fetal progenitors in clonal assays declined in synchrony with activation of the RAG1 locus but was not completely extinguished. Lymphoid differentiation corresponded to patterns of gene expression previously found for adult marrow, but no fraction of fetal liver was enriched with respect to B + T progenitors. Also, unlike adults, fetal lymphoid progenitors transiently expressed endothelial cell markers. These findings help to reconcile discrepancies in previous reports and suggest that the fetal immune system arises via unique mechanisms. 相似文献
994.
Characterization of enteropathogenic and enteroaggregative Escherichia coli isolated from diarrheal outbreaks. 总被引:1,自引:0,他引:1
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Jun Yatsuyanagi Shioko Saito Hiroyasu Sato Yoshimichi Miyajima Ken-Ichi Amano Katsuhiko Enomoto 《Journal of clinical microbiology》2002,40(1):294-297
Virulence characteristics of diarrheal outbreak-associated Escherichia coli O55:NM, O126:NM, and O111:NM were examined. The E. coli O55:NM strains were atypical enteropathogenic E. coli (EPEC), while the E. coli O126:NM and O111:NM strains should be classified as enteroaggregative E. coli (EAggEC). The contributions of EPEC and EAggEC to the human disease burden in Japan might be significantly greater than is currently appreciated. 相似文献
995.
Alterations in the INK4a/ARF locus and their effects on the growth of human osteosarcoma cell lines 总被引:4,自引:0,他引:4
Park YB Park MJ Kimura K Shimizu K Lee SH Yokota J 《Cancer Genetics and Cytogenetics》2002,133(2):105-111
Two different proteins, p16(INK4a) and p14(ARF), encoded by the INK4a/ARF locus play important roles in the RB and p53 pathways, respectively. This study was performed to determine genetic and epigenetic alterations in the INK4a/ARF locus and their effects on the growth of osteosarcoma. Among six cell lines examined, both p16(INK4a) and p14(ARF) exons were homozygously deleted in two cell lines, MG63 and HOS, and both p16(INK4a) and p14(ARF) promoters were methylated in one cell line, U2OS. Wild-type mRNA and proteins for p16(INK4a) and p14(ARF) were expressed in three other cell lines, SaOS2, HuO9, and G292. Transfection studies were performed using two cell lines, U2OS and MG63. Both the RB and p53 genes were wild types in U2OS, whereas p53 but not RB was mutated in MG63. Both p16(INK4a) and p14(ARF) suppressed the growth of U2OS, whereas p16(INK4a) but not p14(ARF) suppressed the growth of MG63. p53 only did not suppress the growth of MG63 either; however, coexpression of p14(ARF) with p53 increased the fraction of the G0/G1 phase in MG63 cells. The data presented here demonstrate the importance of genetic and epigenetic alterations in the INK4a/ARF locus for the growth of osteosarcoma and thus will be useful to further understand the biologic behavior of osteosarcoma in association with the defects in the p53 and RB pathways. 相似文献
996.
997.
抗人DR5抗体mDRA- 6细胞毒作用机制分析 总被引:5,自引:1,他引:5
目的:探讨鼠抗人DR5单克隆抗体(mAb)mDRA-6对Jurkat细胞的细胞毒作用及其机制。方法:以流式细胞术测定mAbmDRA-6对Jurkat细胞的细胞毒作用和细胞凋亡作用,以及caspase8、9的抑制剂对mAbmDRA-6诱导的Jurkat细胞凋亡的影响。在荧光显微镜下,观察mAbmDRA-6对Jurkat细胞形态的影响。以琼脂糖凝胶电泳检测Jurkat细胞中的DNA片段化。结果:mAbmDRA-6对Jurkat细胞具有显著的细胞毒作用,并呈剂量和时间依赖性。经mAbmDRA-6处理后,Jurkat细胞可出现典型的细胞凋亡的形态特征:细胞膜皱缩,出泡,染色质浓缩,形成凋亡小体等。经mAbmDRA-6处理后,Jurkat细胞膜表面高表达丝氨酸磷脂,并可导致Jurkat细胞中的DNA片段化。caspase8的抑制剂可明显抑制mAbmDRA-6诱导的Jurkat细胞凋亡,caspase9的抑制剂的影响很小。结论:mAbmDRA-6可通过死亡受体信号传导途径诱导Jurakt细胞凋亡,对Jurkat细胞产生细胞毒作用,其在以TRAIL/DR5系统进行的肿瘤治疗和探讨DR5功能结构域方面具有广阔的应用前景。 相似文献
998.
Through whole-cell patch recordings in brainstem slices, the effects of histamine on neuronal activity of the lateral vestibular nucleus (LVN) were investigated. Bath application of histamine elicited a concentration-dependent excitation of both spontaneous firing (n = 19) and silent (n = 7) LVN neurons. Moreover, histamine induced a stable inward current in the LVN neurons (n = 5) and the histamine-induced depolarization of membrane potential persisted in the presence of tetrodotoxin (n = 4), indicating a direct post-synaptic effect of the histamine on the LVN neurons. Selective histamine H2 receptor antagonist ranitidine effectively blocked the histamine-evoked excitatory responses on the LVN neurons (n = 4), but selective histamine H1 receptor antagonist triprolidine did not (n = 4). In addition, selective histamine H2 receptor agonist dimaprit (n = 3) rather than 2-pyridylethylamine (n = 4), a selective histamine H1 receptor agonist, mimicked the excitatory action of histamine on LVN neurons. The results demonstrate that histamine excites the LVN neurons via post-synaptic histamine H2 receptors and suggest that the central histaminergic projection arising from the hypothalamus may modulate LVN neurons activity and actively influence the vestibular reflexes and functions. 相似文献
999.
胃癌 (Gastric Cancer,GC) 是全球第五大最常见的恶性肿瘤,也是第四大癌症死亡相关原因。胃癌异质性明显,肿瘤微环境复杂,免疫检查点抑制剂虽然在晚期胃癌中展现出一定抗肿瘤疗效,但获益人群仍在少数。吲哚胺2,3-双加氧酶 1 (Indoleamine 2,3-Dioxygenase 1,IDO1) 是色氨酸沿犬尿氨酸途径代谢中的关键酶,对肿瘤免疫逃逸起到了关键作用。目前已有多项研究表明IDO1在胃癌发生发展及幽门螺杆菌感染和EB病毒感染中发挥重要作用,所以靶向IDO1有望成为胃癌免疫治疗的新策略。本文就IDO1作用机制、IDO1在胃癌及相关疾病中的研究进展及IDO1抑制剂在胃癌中的应用前景进行综述。 相似文献
1000.
Srinivas SM de Boer JF Park H Keikhanzadeh K Huang HE Zhang J Jung WQ Chen Z Nelson JS 《Journal of biomedical optics》2004,9(1):207-212
An assessment of burn depth is a key step in guiding the treatment of patients who have sustained thermal injuries. Polarization-sensitive optical coherence tomography (PS-OCT) might eventually provide the physician with a quantitative estimate of actual burn depth. Burns of various depths were induced by contacting rat skin with a brass rod preheated to 75 degrees C for 5, 15, or 30 s. Thermal injury denatured the collagen in the skin, and PS-OCT imaged the resulting reduction of birefringence through the depth-resolved changes in the polarization state of light propagated and reflected from the sample. Stokes vectors were calculated for each point in the PS-OCT images and the reduction in the rate of phase retardation between two orthogonal polarizations of light (deg/microm) was found to show a consistent trend with burn exposure time. PS-OCT is a noninvasive technique with potential to give the physician the information needed to formulate an optimal treatment plan for burn patients. 相似文献