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31.
目的:评价肾交感神经刺激(Renal sympathetic nerves stimulation,RSNS)对全身交感神经系统的影响。方法12只成年杂种犬随机分为两组:假手术组(Sham组,n=6)和肾交感神经刺激组(RSNS组,n=6)。RSNS组经左肾动脉外膜给予持续2 h高频电刺激,刺激参数:频率20 Hz,脉宽0.1 ms,刺激强度随血压进行调整,以保持血压较刺激前升高10%;假手术组在左肾动脉附近寻找一处体表皮肤给予以同样2 h高频电刺激。分别于基础状态和2 h刺激末检测血压(BP)、心率(HR)、心率变异性(HRV)和血清去甲肾上腺素(NE)浓度。结果与基础状态比较,Sham组成年杂种犬2 h末BR、HR、交感神经活性和血清去甲肾上腺素浓度比较差异均无统计学意义(P>0.05)。与基础状态比较,RSNS可以明显提高成年杂种犬BR、交感神经活性和血清去甲肾上腺素浓度,差异有统计学意义(P<0.05)。结论肾交感神经刺激可以明显提高全身交感神经系统活性。 相似文献
32.
复杂性尿道狭窄或闭锁的处理一直是泌尿外科最棘手的难题之一,尤其是对初次或再次治疗失败后的复杂性超长段尿道狭窄或闭锁(> 14 cm)患者的治疗,作者在治疗复杂性尿道狭窄及其并发症中取得了一系列的原创性成果.与国内外的同类研究比较,主要有以下发现和创新点.①在国际上首次提出并证实结肠黏膜可作为尿道替代物;临床治疗55例超长段尿道狭窄(平均15.2 cm)的结果提示结肠黏膜具有材源丰富、易于剥离、抗感染力强、皱缩率低等优点,适于14 cm以上尿道的重建,尤其是多次治疗失败的复杂性超长段尿道狭窄.②在国际上首次建立新型分期手术治疗复杂性超长段狭窄或闭锁,临床应用11例,疗效显著,为难治性前后尿道间长段狭窄或闭锁提供了一个新的思路.③在国际上首次阐述舌黏膜尿道重建的病理学特征及转归,建立大面积舌黏膜取材新技术;在国内率先开展舌黏膜尿道成形术,样本量为国内外最大.④在国际上首次建立了尿道压客观量化指标(90 cmH2O或较基础压提高40 ~50 cmH2O),用于评估球部尿道悬吊术中尿道压力.从而提高了手术成功率,减少了并发症,取得了显著治疗效果.该系列研究成果先后获省部科技进步一等奖和多项二等奖. 相似文献
33.
目的:探讨柠檬酸对术后首次行131I治疗(简称清甲治疗)的分化型甲状腺癌(DTC)患者唾液腺功能的影响,阐明柠檬酸对131I治疗的甲状腺癌患者唾液腺功能的保护作用。方法:经患者知情同意,随机选择准备首次行131I治疗的68例甲状腺乳头状癌患者,随机分为对照组和柠檬酸组,每组34例。对照组患者无特殊准备,柠檬酸组患者于131I治疗前1周及治疗后3周内每天含柠檬酸1 min(0.2 g/次)后吐出。2组患者分别于131I治疗前24 h及131I治疗后3个月行2次99mTcO4-唾液腺显像检查,计算第15分钟摄取指数(15 min UI)和排泌分数(SR),评估唾液腺功能。结果:与131I治疗前比较,对照组患者131I治疗后右侧腮腺和双侧颌下腺15 min UI差异无统计学意义(P>0.05),左侧腮腺15 min UI降低(P<0.05);与131I治疗前比较,柠檬酸组患者131I治疗后双侧腮腺及双侧颌下腺15 min UI差异无统计学意义(P>0.05);与对照组比较,柠檬酸组患者131I治疗前后双侧腮腺和双侧颌下腺15 min UI差异均无统计学意义(P>0.05)。与131I治疗前比较,对照组患者双侧腮腺治疗后SR降低(P<0.05),双侧颌下腺SR差异无统计学意义(P>0.05),柠檬酸组患者双侧腮腺和双侧颌下腺治疗后SR差异无统计学意义(P>0.05);与对照组131I治疗后比较,柠檬酸组患者双侧腮腺SR升高(P<0.05),双侧颌下腺SR差异无统计学意义(P>0.05)。结论:DTC患者术后首次131I治疗后唾液腺排泌功能可能受损,短期口含柠檬酸对唾液腺具有保护作用,可以减轻唾液腺的放射性损伤。 相似文献
34.
35.
Daniel M. Caruso M.D. Andrew A. Kassir M.D. Ramon A. Robles M.D. Michael W. Gregory M.D. Ryan B. Tsujimura M.D. Peter Cheung M.D. Peter J. Ferrara M.D. 《Diseases of the colon and rectum》1996,39(11):1222-1226
Introduction: Sigmoid volvulus is a disease of the elderly who often have severe comorbid conditions that increase their operative risk and limit treatment options. Conservative treatment with decompression
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sigmoidoscopy with rectal tube placement has high success and recurrence rates. Surgical resection with primary anastomosis is the treatment of choice when decompression fails or if the volvulus recurs. Unfortunately, perioperative complications are frequent. Moreover, many patients with sigmoid volvulus are bedridden or incontinent of stool and do not benefit from extensive resection and maintenance of bowel continuity. METHODS: Twelve debilitated patients with sigmoid volvulus determined preoperatively to be poor candidates for laparotomy and reanastomosis were treated with a trephine stoma. Initially, each patient had decompression
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rigid sigmoidoscopy and rectal tube placement. Surgical intervention consisted of formation of a small hole (trephine) in the left lower quadrant. Through this hole, a sigmoid resection and end colostomy were performed. No midline laparotomy was required. RESULTS: Operative times and analgesia requirements were significantly decreased (P
=0.05) compared with patients who underwent formal laparotomy. Length of hospital stay, complication rates, and length of bowel resected were similar using either surgical technique. CONCLUSIONS: The trephine stoma procedure offers significantly shorter operative times, with decreased perioperative morbidity. For high operative risk or debilitated patients with sigmoid volvulus, resection with end colostomy using the trephine stoma technique is the procedure of choice.Presented at the meeting of the Zollinger Surgical Society, Columbus, Ohio, September 5 to 7, 1996. 相似文献
36.
Interactions between vascular endothelial cells and blood platelets have been investigated using a model microcirculation consisting of microcarrier beads colonized with human umbilical vein endothelial cells (HUVECs) and perfused with washed platelet suspensions. To simulate the effects of endothelial desquamation and exposure of subendothelium, fibrillar collagen in suspension was coinjected with the platelets. In this model, neither the passage of platelets alone nor collagen alone stimulated prostacyclin (PGI2) production by the HUVECs. Platelets activated by coinjection with collagen released thromboxane A2 (TXA2), and this was associated with the simultaneous production of PGI2 by the HUVECs. By means of double-isotope experiments with [3H]arachidonic acid (AA) incorporated into platelets and [14C]-AA into HUVECs, it was shown that all the PGI2 generated was derived from platelet AA and/or endoperoxides. This interpretation was strengthened by the finding that PGI2 production was not prevented by treatment of HUVECs with indomethacin followed by perfusion with collagen-stimulated platelets. AA metabolites in double-isotope label experiments were further characterized by reverse-phase chromatography, and it was shown that both cyclooxygenase and lipoxygenase products of the HUVECs were derived from platelet membrane lipid. Thrombin regularly produced transient PGI2 release, but showed rapid tachyphylaxis. Platelet-derived compounds including ADP, ATP, and platelet-activating factor (PAF) did not produce PGI2 release by HUVECs in this system. Thus, the transfer of AA and metabolites from collagen- stimulated platelets is likely to be the mechanism for PGI2 production in the context of minor degrees of endothelial desquamation. 相似文献
37.
N Senst M Llacuachaqui J Lubinski H Lynch S Armel S Neuhausen P Ghadirian P Sun SA Narod 《Clinical genetics》2013,84(1):43-46
The objective is to estimate the risk of breast cancer in women who carry a deleterious BRCA1 or BRCA2 mutation, according to parental origin of mutation. We conducted a cohort study of women with a BRCA1 mutation (n = 1523) or BRCA2 mutation (n = 369) who had not been diagnosed with breast or ovarian cancer. For each woman, the pedigree was reviewed and the origin of the mutation was assigned as probable paternal or maternal. The hazard ratio (HR) for developing breast cancer in the follow‐up period was estimated for women with a paternal mutation compared to a maternal mutation. The risk of breast cancer was modestly higher in women with a paternal BRCA1 mutation compared to women with a maternal BRCA1 mutation (HR = 1.46; 95% CI = 0.99–2.16) but the difference was not significant (p = 0.06). The parental mutation origin did not affect the risk in women with a BRCA2 mutation. Our results are consistent with the hypothesis that there is an increased risk of breast cancer among women with a paternally inherited BRCA1 mutation compared to a maternally inherited mutation. However, the data are not sufficiently compelling to justify different screening recommendations for the two subgroups. 相似文献
38.
MB Delatycki M Wolthuizen MA Aitken C Hickerton SA Metcalfe KJ Allen 《Clinical genetics》2013,84(3):286-289
Hereditary hemochromatosis (HH) is a common preventable disorder of iron overload that can result in liver cirrhosis and reduced lifespan. Most HH is due to homozygosity for the HFE p.C282Y substitution. We conducted a study of screening for p.C282Y in high schools where p.C282Y heterozygotes (CY) individuals were informed of their genotype by letter. We studied whether these individuals understood the implications of their genotype, whether this resulted in anxiety or reduced health perception and whether cascade testing was higher in families of CY than wild‐type homozygous (CC) individuals. We found 586 of 5757 (1 in 10) screened individuals were CY. One month after receiving their result, 83% correctly answered that they have one copy of p.C282Y. There was no adverse change in anxiety or health perception from prior to screening to 1 month after receiving results. Significantly more family members of CY individuals than CC individuals were informed about HH and had testing for HH. In conclusion, we found that informing CY individuals of their genotype does not increase anxiety and the implications are generally well understood. This leads to cascade testing in a minority of families. CY individuals should be informed of their genetic status when identified by population screening. 相似文献
39.
目的:对蒙药苏格木勒-3水提物进行化学成分研究,构建较为全面的化学成分谱,为苏格木勒-3水提物有效物质基础研究奠定基础。方法:采用超高液相色谱串联四级杆飞行时间质谱(UPLC-Q-TOF-MS)技术,使用ESI离子源,通过mzCloud与mzVoult软件以及质谱裂解规律,并结合对照品及相关文献资料比对进行定性分析。结果:经过分析,从蒙药苏格木勒-3水提物中共鉴定出42个成分,主要包括氨基酸、酚酸类、黄酮类、内酯类、生物碱类及其他类等6类成分,并对各成分的药材来源进行归属。结论:本研究全面、快速、准确地分析了蒙药苏格木勒-3水提物的化学成分,为其药效物质基础和质量控制等研究奠定了基础。 相似文献
40.
Molecular heterogeneity in acute leukemia lineage switch 总被引:1,自引:0,他引:1
Gagnon GA; Childs CC; LeMaistre A; Keating M; Cork A; Trujillo JM; Nellis K; Freireich E; Stass SA 《Blood》1989,74(6):2088-2095
Six cases of acute leukemia that underwent lineage switch from acute lymphocytic leukemia to acute myelogenous leukemia are reported. The mean age of the patients was 24 years, time to conversion was 36 months, and survival after conversion was only 3 months. Of the three cases which showed abnormal metaphases at both diagnosis and conversion, two (cases 2, 5) showed related cytogenetic abnormalities, and the third showed (case 3) independent chromosomal changes. Molecular analysis for immunoglobulin heavy chain and T-cell receptor beta chain genes showed that five of the six cases had rearrangement of at least one of these lymphoid associated genes at conversion to acute myelogenous leukemia. The single case (case 3) in which there were no lymphoid gene rearrangements at conversion was also the only case in which independent karyotypic abnormalities at diagnosis and conversion were demonstrated. Our findings suggest that lineage switch can represent either relapse of the original clone with heterogeneity at the molecular level or the emergence of a second new leukemic clone without molecular heterogeneity. 相似文献