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91.
本文利用透射电镜和图象分析仪对三组不同年龄大鼠肾集合管上皮细胞进行了观察和分析。结果表明:(1)初生组大鼠肾集合管上皮细胞的核质比明显大于青年组和成年组,而青年组与成年组的核质比则无明显差别;(2)细胞形态包括细胞间连接、细胞基底部的质膜内褶等方面,初生组与青年组、成年组都有较大的变化。  相似文献   
92.
Extended-spectrum beta-lactamases (ESBLs) are often mediated by (bla-)SHV, (bla)TEM and (bla)CTX-M genes in Enterobacteriaceae and other Gram-negative bacteria. Numerous molecular typing methods, including PCR-based assays, have been developed for their identification. To reduce the number of PCR amplifications needed we have developed a multiplex PCR assay which detects and discriminates between (bla-)SHV, (bla)TEM and (bla)CTX-M PCR amplicons of 747, 445 and 593 bp, respectively. This multiplex PCR assay allowed the identification of (bla-)SHV, (bla)TEM and (bla)CTX-M genes in a series of clinical isolates of Enterobacteriaceae with previously characterised ESBL phenotype. The presence of (bla)SHV, (bla)TEM and (bla)CTX-M genes was confirmed by partial DNA sequence analysis. Apparently, the universal well-established CTX-M primer pair used here to reveal plasmid-encoded (bla)CTX-M genes would also amplify the chromosomally located K-1 enzyme gene in all Klebsiella oxytoca strains included in the study.  相似文献   
93.
It is accepted that alteration of connexin43 (Cx43) expression in glomeruli is a common pathological response in several forms of kidney diseases. To date, however the change of the Cx43 expression in obesity-related glomerulopathy (ORG) has not been reported. In this study, the alteration of Cx43 expression in the glomeruli of rat with ORG was defined. Five-week-old rats were fed with high-fat diet for 18 weeks to establish the ORG model, then the histological change of glomeruli, the foot process effacement of podocyte, the markers for podocyte injury (nephrin,podocin and WT1) and Cx43 expression in glomeruli were examined respectively. The results demonstrated metabolic disorder, hyperinsulinemia, systemic inflammation and microalbuminuria in ORG rats. There was significant hypertrophy, glomerular expansion and inflammatory cell infiltration in the kidney of ORG rats compared to the control group. Significant foot process effacement of the podocyte in the glomeruli, nephrin loss and density reduction were shown in the ORG rats, and Cx43 expression was significant upregulated in glomeruli of ORG rats compared to the control group. The results indicate the correlation of overexpressed Cx43 with the obesity related renal inflammation and suggest that Cx43 might be a potential target in the development of obesity related glomerulopathy.  相似文献   
94.
95.
Purpose The aim of this study is to evaluate the safety and efficacy of endoluminal loco-regional resection (ELRR) by transanal endoscopic microsurgery (TEM) after R1 endoscopic resection or local recurrence of early rectal cancer after operative endoscopy. Material and methods Twenty patients with early rectal cancer were enrolled, including patients with incomplete endoscopic resection, or complete endoscopic resection of a tumor with unfavorable prognostic factors (group A, ten patients), and local recurrence after endoscopic removal (group B, ten patients). At admission, histology after endoscopic polypectomy was: TisR1(4), T1R0G3(1), T1R1(5) in group A, and TisR0(8), T1R0(2) in group B. All patients underwent ELRR by TEM with nucleotide-guided mesorectal excision (NGME). Results Mean operative time was 150?minutes. Complications occurred in two patients (10%). Definitive histology was: moderate dysplasia(4), pT0N0(3), pTisN0(5), pT1N0(6), pT2N0(2). Mean number of lymph-nodes was 3.1. Mean follow-up was 79.5 months. All patients are alive and disease-free. Conclusions ELRR by TEM after R1 endoscopic resection of early rectal cancer or for local recurrence after operative endoscopy is safe and effective. It may be considered as a diagnostic procedure, as well as a curative treatment option, instead of a more invasive TME.  相似文献   
96.

Aims

Laminaria Japonica Polysaccharides (LJP) is a kind of plant polysaccharide isolated from Laminaria Japonica Aresch. LJP has a variety of biological activity, including anti-tumor, improving immune function, anti-radiation and others. This study observed the biological activity of LJP in vitro and in vivo on human nasopharyngeal carcinoma(NPC), and the possible anticancer mechanism was explored.

Methods

Nasopharyngeal poorly differentiated squamous cell carcinoma cell lines CNE2 and HONE1 were used for the study. MTT method was used to detect the proliferation of HONE1 and CNE2 treated with gradient concentrations of LJP. The apoptosis of HONE1 treated with LJP was detected by annexin V-FITC/PI double staining method. HONE1 was used to establish subcutaneous implanted tumor model in nude mice. The changes of transplanted tumor volume and body weight of nude mice in each group were observed and recorded. The changes of the ultrastructure of transplanted tumor were observed by transmission electron microscope (TEM).

Results

MTT results showed that LJP has inhibitory effect on proliferation of both HONE1 and CNE2, and the effects were dosage-dependent; results of flow cytometry (FCM) analysis showed that, LJP could efficient induce apoptosis in HONE1, and apoptosis rate increased with the increase of LJP concentration. In vivo experiments, the inhibition rate was 33.7% (P < 0.05) and 47% (P < 0.01) in middle and high dose LJP group, respectively. TEM results suggested that the cancer cells in the transplanted tumor tissue treated with middle and high dose LJP presented unique apoptosis changes.

Conclusions

LJP can effectively inhibit the growth of NPC cells. And it may be achieved by inducing apoptosis of NPC cells.  相似文献   
97.
98.
The goal of treatment for early stage rectal cancer is to optimize oncologic control while minimizing the long-term impact of treatment on quality of life. The standard of care treatment for most stage I and II rectal cancers is radical surgery alone, specifically total mesorectal excision (TME). For early rectal cancers, this procedure is usually curative but can have a substantial impact on quality of life, including the possibility of permanent colostomy and the potential for short and long-term bowel, bladder, and sexual dysfunction. Given the morbidity associated with radical surgery, alternative approaches to management of early rectal cancer have been explored, including local excision (LE) via transanal excision (TAE) or transanal endoscopic microsurgery (TEM) and transanal minimally invasive surgery (TAMIS). Compared to the gold standard of radical surgery, local procedures for strictly selected early rectal cancers should lead to identical oncological results and even better outcomes regarding morbidity, mortality, and quality of life.  相似文献   
99.
Eight- and sixteen-channel transceive stripline/TEM body arrays were compared at 7 T (297 MHz) both in simulation and experiment. Despite previous demonstrations of similar arrays for use in body applications, a quantitative comparison of the two configurations has not been undertaken to date. Results were obtained on a male pelvis for assessing transmit, signal to noise ratio, and parallel imaging performance and to evaluate local power deposition versus transmit B(1) (B(1) (+) ). All measurements and simulations were conducted after performing local B(1) (+) phase shimming in the region of the prostate. Despite the additional challenges of decoupling immediately adjacent coils, the sixteen-channel array demonstrated improved or nearly equivalent performance to the eight-channel array based on the evaluation criteria. Experimentally, transmit performance and signal to noise ratio were 22% higher for the sixteen-channel array while significantly increased reduction factors were achievable in the left-right direction for parallel imaging. Finite difference time domain simulations demonstrated similar results with respect to transmit and parallel imaging performance, however, a higher transmit efficiency advantage of 33% was predicted. Simulations at both 3 and 7 T verified the expected parallel imaging improvements with increasing field strength and showed that, for a specific B(1) (+) shimming strategy used, the sixteen-channel array exhibited lower local and global specific absorption rate for a given B(1) (+) .  相似文献   
100.
Minimally invasive surgery for early lower GI cancer   总被引:1,自引:0,他引:1  
Two technical developments in colorectal surgery-i.e. transanal endoscopic microsurgery (TEM) and laparoscopic surgery for colorectal disease-are now available for the treatment of early lower GI cancer. Benign lesions and early-stage tumours of the rectosigmoid are amenable for a transanal approach. Transanal endoscopic microsurgery is performed using a rectoscope 4 cm in diameter with a four-port insert. After installation of a pneumorectum, lesions up to 25 cm from the anal verge, including circumferential lesions, can be removed with a recurrence rate of 0-5% for adenomas, 3% for low-risk T1 carcinomas, and 8% for all carcinomas. Laparoscopic-assisted colonoscopic polypectomy, laparoscopic wedge resection or laparoscopic-assisted colostomy have a 67-100% success rate for avoiding a formal bowel resection for benign tumours that cannot be treated by colonoscopy alone. Early colonic cancer requires laparoscopic colectomy guided by preoperative colonoscopy or preoperative endoscopic tattooing for localisation of the affected segment.  相似文献   
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