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41.
目的:检测lnc-CCDC33-1:1在甲状腺乳头状癌(PTC)中的表达,并分析其临床意义。方法:选取2021年11月至2022年3月杭州市萧山区第一人民医院收治的120例PTC患者,收集120例PTC组织及30例癌旁正常甲状腺组织。采用qRT-PCR检测lnc-CCDC33-1:1在PTC组织及癌旁组织中的表达。分析本地队列和TCGA队列中lnc-CCDC33-1:1表达水平与PTC患者临床病理因素的相关性。采用受试者工作特征(ROC)曲线评价lnc-CCDC33-1:1对PTC的诊断价值。结果:与癌旁正常甲状腺组织比,lnc-CCDC33-1:1在PTC组织中表达明显升高(P <0.001)。ROC曲线显示曲线下面积为0.803(95%CI =0.736~0.869,P <0.001)。本地队列显示lnc-CCDC33-1:1 表达与PTC肿瘤大小(P =0.048)、腺外侵犯(P =0.019)、T分期(P =0.011)和淋巴结转移(P =0.009)相关,TCGA组数据显示lnc-CCDC33-1:1表达水平与PTC腺外侵犯(P =0.036)和淋巴结转移(P <0.001)相关。结论:lnc-CCDC33-1:1在PTC中表达异常升高,与PTC高危特征相关,可能是潜在的诊断标志物和治疗靶点。 相似文献
42.
43.
PAOLO ALBONI NELLY PAPARELLA RICCARDO CAPPATO PAOLO PEDRONI GIAN CARLO CANDINI GIAN ENRICO ANTONIOLI 《Pacing and clinical electrophysiology : PACE》1989,12(2):294-300
The purpose of this study was to find out whether transesophageal pacing could be utilized for assessment of sinus node function in patients with sick sinus syndrome (SSS). In 17 patients with SSS (study group) we compared the results of sinus node tests obtained both in the basal state and after pharmacological autonomic blockade by endocavitary stimulation and, 24 hours later, by transesophageal pacing. In another group of 17 patients with SSS (control group), we compared the results obtained by two endocavitary studies. In "study group", sinus cycle length (SCL) and corrected sinus node recovery time (CSRT) did not show significant differences between the two studies both in the basal state and after autonomic blockade, whereas sinoatrial conduction time (SACT) was more prolonged during esophageal pacing (P less than 0.01). In "control group", sinus node measures did not show significant differences between the two studies. In the "study group," the following coefficients of correlation were obtained in the basal state; SCL, r = 0.65, CSRT, r = 0.57, SACT, r = 0.52 and after autonomic blockade: SCL, r = 0.95, CSRT, r = 0.62 and SACT, r = 0.53. In the basal state, the correlation for SCL and CSRT between the two studies was lower in the "study group" than in the "control group" (P less than 0.05), whereas after autonomic blockade the correlation for sinus node measures did not show significant differences between the two groups of patients. These data suggest that transesophageal study influences the autonomic tone regulating the sinus node; however, it is not responsible for important variations in sinus node measures.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
44.
Grabau DA Rank F Friis E 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2005,113(1):7-12
The study presents the results from intraoperative frozen section assessment of axillary sentinel lymph nodes (SLNs) in breast cancer. Routine histological frozen sections from one level were used, two sections stained with haematoxylin and eosin. Immunohistochemistry for cytokeratins was applied to the permanent SLN paraffin sections only. Axillary dissection was performed on all SLN-positive cases regardless of the size of the metastatic deposits. With a detection rate of 83%, 272 patients entered the study over a period of 46 months. A total of 61 cases were SLN positive by frozen section analysis. The paraffin sections gave an additional 23 SLN-positive cases. The false-negative rate for frozen sections was then 27% (23/84). Micrometastases were found in 28 of 84 cases, and macrometastases in 56. The false-negative rate of frozen sections for micrometastases was 71% (20/28), and for macrometastases 5% (3/56). A total of 73% (61/84) of the patients underwent axillary surgery as a one-step procedure. 相似文献
45.
Jiqing Guo Tamotsu Mitsuiye A. Noma 《Pflügers Archiv : European journal of physiology》1997,433(4):390-396
Single myocytes were dissociated from the sino-atrial (SA) node of guinea-pig hearts. Only a quite small fraction of the
cell population showed spontaneous action potentials and these cells were characterized by the presence of the hyperpolarization-activated
cation current I
f , the delayed rectifier K+ current I
K and the L-type Ca2+ current I
Ca,L as well as by the absence of both the transient outward current I
to and the inward rectifier K+ current I
K,1. After blocking I
f and I
K, depolarizing pulses from –80 mV revealed a large nicardipine-sensitive late current (NSLC). The NSLC was scarcely affected
by decreasing extracellular [Ca2+] ([Ca2+]o) from 1.8 to 0.1 mM, while it was decreased significantly by depleting [Na+]o, differently from I
Ca,L. NSLC was blocked by nicardipine and was increased by Bay K 8644. NSLC was increased by isoprenaline and the additional application
of acetylcholine reversed the increase of this current. We conclude that NSLC is largely composed of I
st described in the rabbit SA node pacemaker cells, and that I
st is unique for the pacemaker cells in mammalian SA node cells. Most of the quiescent cells showed neither I
f nor I
st.
Received: 22 July 1996 / Received after revision: 30 September 1996 / Accepted: 9 October 1996 相似文献
46.
Deborah U Frank Sarah A Elliott Eon Joo Park Jennetta Hammond Yukio Saijoh Anne M Moon 《Developmental dynamics》2007,236(4):1085-1092
We targeted the reverse tetracycline controlled transactivator (rtTA) to the Foxa2 locus (Foxa2(ITA)) to generate a system for regulating Cre-recombinase activity within Foxa2 expression domains, including the endoderm, notochord, and floor plate of early mouse embryos. The use of an internal ribosomal entry site to obtain rtTA expression preserves Foxa2 function of the targeted allele. Cre activity with this system reflects the level of endogenous Foxa2 activity and is also tightly controlled by doxycycline. The location of Cre activity within the broader Foxa2 expression domain can be restricted by altering the timing of doxycycline administration. Isolated floor plate expression can be obtained in this manner. This system will provide a useful tool for manipulating gene expression in endoderm, notochord, and floor plate, all of which are tissues with important structural and patterning functions during embryogenesis. 相似文献
47.
Class switch recombination (CSR), somatic hypermutation, and gene conversion are immunoglobulin diversification mechanisms that are strictly dependent on the activity of the activation-induced cytidine deaminase (AID). The precise role and substrate(s) of AID in these processes remain to be well defined. The closest homologue of AID is APOBEC-1, a bona fide mRNA-editing enzyme, which shares with AID the ability to deaminate cytidines within single-stranded DNA in vitro and in prokaryotic cells. To determine whether APOBEC-1 can therefore substitute for AID in activated B cells, we expressed human AID, a catalytic mutant thereof, and rat APOBEC-1 in AID-deficient murine B cells. Whereas AID rescued CSR, neither the inactive mutant nor APOBEC-1 could complement AID deficiency. This indicates that cytidine deaminase activity is necessary but not sufficient to initiate CSR, and suggests that AID is specifically targeted to its cognate substrate, the immunoglobulin genes or a distinct mRNA, by an as-yet-unknown mechanism. 相似文献
48.
How many lymph nodes are necessary to stage early and advanced adenocarcinoma of the sigmoid colon and upper rectum? 总被引:5,自引:0,他引:5
Leibl S Tsybrovskyy O Denk H 《Virchows Archiv : an international journal of pathology》2003,443(2):133-138
The lymph-node yields in specimens resected for colorectal adenocarcinoma show considerable variations, raising the question whether the minimum lymph-node number recommended by the UICC (International Union Against Cancer) for pN0 classification represents an appropriate quality standard for specimen work-up. The number of pericolic lymph nodes recovered from 568 archival surgical colorectal carcinoma specimens located in the sigmoid or upper rectum showed a highly statistically significant correlation with both the pT category and the presence of metastases (P<0.0005). The median lymph-node yield in standardized (i.e., resembling in size surgically removed cancer specimens) tumor-free specimens obtained during autopsies was 13 lymph nodes, compared with 20.5 when diverticula were present and more than 30 in specimens with chronic inflammation or from patients with systemic infections. In 48 pT2 and pT3 carcinoma specimens prospectively dissected in the same way, median numbers of 18 (pT2) and 23 (pT3) lymph nodes were detected (range between 8 and 39 nodes). The lymph-node numbers recommended in previous studies and by the UICC often seem to be too low to declare a specimen free of metastases. Although the great variation in lymph-node counts requires the recovery of all lymph nodes for pN0 classification, recommendations considering the pT status and additional factors like diverticula and inflammatory changes can be useful as a quality standard for specimen work up. 相似文献
49.
对12例经病理学专家会诊、从病变上认定的淋巴结“结节病”石蜡包埋组织,应用结核杆菌DNA特异性序列片段的聚合酶链反应(M.TB-PCR)技术、BCG免疫组化(BCG-IHC)技术和抗酸染色(AF)进行了分支杆菌/结核杆菌检测。在这12例考虑为“结节病”的病例中:有1例呈BCG-IHC和M。TB-PCR两项阳性;另1例呈AF、BCG-IHC和M.TB-PCR三项阳性。研究结果提示:(1)某些结核性淋巴结炎可呈结节病样病变;(2)淋巴结结节病很可能与分支杆菌/结核杆菌感染有关。 相似文献
50.