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排序方式: 共有408条查询结果,搜索用时 406 毫秒
91.
目的:观察不同剂量的盐酸右旋美托咪定对脑膜瘤切除术患者全麻围拔管期应激反应的影响。方法:60 例ASAI~Ⅱ级,年
龄25-65 岁脑膜瘤切除术患者,随机分为四组,NS、D1、D2 和D3 组,NS 组:静脉泵入等量的生理盐水,D1、D2 和D3组静脉泵注
负荷量均为0.6 滋g/kg 的盐酸右旋美托咪定,各组泵注时间均为10 分钟,输注结束后随之给予维持量,D1组:盐酸右旋美托咪定
维持量0.2 滋g·kg-1·hr-1;D2 组:盐酸右旋美托咪定维持量0.4 滋g·kg-1·hr-1;D3组:盐酸右旋美托咪定维持量0.6 滋g·kg-1·hr-1。观察
并记录拔管时的耐管评分、呛咳程度、警觉/ 镇静评分(OAA/S)、拔管时间及拔管即刻和拔管后3 min 的平均动脉压(MAP)、心率
(HR)及恶心、寒战等不良反应。结果:D3 组患者耐管评分高于D1 组、D2 组和NS 组,呛咳程度轻于D1 组、D2 组和NS 组(P<0.
05);D2、D3 组患者拔管即刻和拔管后3 min 的MDP、HR 均明显低于D1 组(P<0.05);D1、D2 和D3 组不良反应少于NS 组;四组
拔管时间无明显差异。结论:盐酸右旋美托咪定降低脑膜瘤切除术患者全麻围拔管期的应激反应,增强患者对气管导管的耐受
性。 相似文献
92.
目的:探究关闭盆底腹膜在腹腔镜直肠癌Miles根治术中的意义。方法:选取2012年3月至2014年3月我院治疗的拟行腹腔镜直肠癌Miles根治术患者48例,按随机数字法分为观察组和对照组各24例,观察组在腹腔镜Miles根治术后关闭盆底腹膜,而对照组则不关闭。比较两组手术时间、骶前引流总量、切口感染率及肠梗阻发生率。结果:观察组的手术时间较对照组长(t=5.207,P=0.000),但两组的骶前引流总量、切口感染率和肠梗阻发生率差异无统计学意义(P=0.210、1.000、0.602)。观察组术后分别有3例(12.50%),对照组有2例(8.33%)患者因肿瘤复发而采取放射治疗,其中仅对照组2例患者出现放射性小肠炎。结论:是否关闭盆底腹膜在腹腔镜直肠癌Miles根治术术后疗效差异不大,但关闭盆底腹膜可有效预防术后放射性治疗中放射性小肠炎的发生。 相似文献
93.
目的:探讨腹腔镜和开腹手术对结直肠癌根治术患者外周血鸟苷酸环化酶C(GCC)m RNA和人端粒酶逆转录酶(h TERT)m RNA表达的影响及其意义。方法:按照随机数字表法将2009年8月-2014年4月我院收治的结直肠癌患者分为腹腔镜组和开腹手术组,通过逆转录-聚合酶链反应技术(RT-PCR)检测并比较两组患者外周血GCC m RNA和h TERT m RNA的表达情况。结果:与开腹手术组相比较,腹腔镜组患者手术时间长、术中出血量少、术后排气早、住院时间短,差异有统计学意义(P0.01);两组患者手术前GCC m RNA和h TERT m RNA阳性率无显著差异(P0.05);两组患者手术后GCC m RNA和h TERT m RNA阳性率显著升高,差异有统计学意义(P0.05)。结论:腹腔镜和开腹手术均会增加结直肠癌患者血行微转移,但腹腔镜结直肠根治术不会增加术后肿瘤血循环微转移的危险性。 相似文献
94.
《DNA Repair》2015
DNA double strand break (DSB) repair pathway choice following ionizing radiation (IR) is currently an appealing research topic, which is still largely unclear. Our recent paper indicated that the complexity of DSBs is a critical factor that enhances DNA end resection. It has been well accepted that the RPA-coated single strand DNA produced by resection is a signaling structure for ATR activation. Therefore, taking advantage of high linear energy transfer (LET) radiation to effectively produce complex DSBs, we investigated how the complexity of DSB influences the function of ATR pathway on the G2/M checkpoint regulation. Human skin fibroblast cells with or without ATM were irradiated with X rays or heavy ion particles, and dual-parameter flow cytometry was used to quantitatively assess the mitotic entry at early period post radiation by detecting the cells positive for phosphor histone H3. In ATM-deficient cells, ATR pathway played a pivotal role and functioned in a dose- and LET-dependent way to regulate the early G2/M arrest even as low as 0.2 Gy for heavy ion radiation, which indicated that ATR pathway could be rapidly activated and functioned in an ATM-independent, but DSB complexity-dependent manner following exposure to IR. Furthermore, ATR pathway also functioned more efficiently in ATM-proficient cells to block G2 to M transition at early period of particle radiation exposure. Accordingly, in contrast to ATM inhibitor, ATR inhibitor had a more effective radiosensitizing effect on survival fraction following heavy ion beams as compared with X ray radiation. Taken together, our results reveal that the complexity of DSBs is a crucial factor for the activation of ATR pathway for G2/M checkpoint regulation, and ATM-dependent end resection is not essential for the activation. 相似文献
95.
The relationship between albumin, other plasma proteins and variables, and age in the acute phase response after liver resection in man 总被引:2,自引:0,他引:2
Summary. A large series of plasma albumin (ALB, g/dl) and simultaneous blood and clinical measurements were prospectively performed
on 92 liver resection patients, and processed to assess the correlations between ALB, other plasma proteins, additional variables
and clinical events. The measurements were performed preoperatively and at postoperative day 1, 3 and 7 in all patients, and
subsequently only in those who developed complications or died. In patients who recovered normally ALB was 4.3 ± 0.4 g/dl
(mean ± SD) preoperatively, 3.7 ± 0.7 at day 1 and 3, and 3.9 ± 0.4 at day 7. In patients with complications its decrease
was more prolonged. In non-survivors it was 3.4 ± 0.4 preoperatively, 3.0 ± 0.4 at day 1, and then decreased further. Regression
analysis showed direct correlations between ALB and pseudo-cholinesterase (CHE, U/l, nv 5300-13000), cholesterol (CHOL, mg/dl),
iron binding capacity (IBC, mg/dl), prothrombin activity (PA, % of standard reference) and fibrinogen, an inverse correlation
with blood urea nitrogen (BUN, mg/dl) for any given creatinine level (CREAT, mg/dl), and weaker direct correlations with hematocrit,
other variables and dose of exogenous albumin. An inverse relationship found between ALB and age (AGE, years) became postoperatively
(POSTOP) also a function of outcome, showing larger age-related decreases in ALB associated with complications (COMPL: sepsis,
liver insufficiency) or death (DEATH). Main overall correlations: CHE = 287.4(2.014)ALB, r = 0.73; CHOL = 16.5(1.610)ALB (1.001)ALKPH, r = 0.71; IBC = 68.6(1.391)ALB, r = 0.64; PA = 13.8 + 16.0(ALB), r = 0.51; BUN = 21.3 + 20.2(CREAT) – 6.2(ALB), r = 0.91; ALB = 5.0–0.013(AGE) – {0.5 +
0.003(AGE)
COMPL
+ 0.012(AGE)
DEATH
}
POSTOP
, r = 0.74 [p < 0.001 for each regression and each coefficient; ALKPH = alkaline phosphatase, U/l, nv 98-279, independent
determinant of CHOL; discontinuous variables in italics label the change in regression slope or intercept associated with
the corresponding condition]. These results suggest that altered albumin synthesis (or altered synthesis unable to compensate
for albumin loss, catabolism or redistribution) is an important determinant of hypoalbuminemia after hepatectomy. The correlations
with age and postoperative outcome support the concept that hypoalbuminemia is a marker of pathophysiologic frailty associated
with increasing age, and amplified by the challenges of postoperative illness. 相似文献
96.
A ground section was prepared from a lower right M3 attributed to Gigantopithecus blacki as close as possible to axial plane of the mesial cusps. Daily cross striations were imaged, measured and counted in each cusp using polarised light microscopy. Long-period striae of Retzius were counted in the lateral enamel and their periodicity determined from counts and measurements of daily cross striations between adjacent striae. Cross striation spacings in the cusps were between 3.8 microm at the enamel dentine junction and 6 microm close to the enamel surface. Cuspal enamel formation times were long (800 days in the protoconid and 620 days in the metaconid). Linear enamel thickness was as much as 3.75 mm in the protoconid. There were 63 and 61 long-period striae of Retzius in the mesial aspects of the lateral enamel and the periodicity was 11 days. Lateral enamel formation took 1493 and 1291 days and when summed with cuspal enamel formation times totalled 4 years in the protoconid and 3.5 in the metaconid. Relative enamel thickness was 23, calculated through the mesial cusps. This falls short of that in the so-called 'thick hyper-thick' enamel described in 'robust' australopithecines to which Gigantopithecus blacki has previously been compared in both its dental and mandibular morphology. With respect to enamel thickness, therefore, Gigantopithecus blacki falls squarely among an increasingly large number of Miocene hominoids that can all be described as having 'thick enamel'. 相似文献
97.
98.
Synopsis The post-metamorphic common sole, Solea solea, as well as the other Soleidae and Cynoglossidae, are characterized by oral jaw elements without teeth on the ocular side. A relatively large proportion of late sole larvae and early juveniles, routinely reared in the laboratory, showed dentigerous and shape-modified premaxillae and mandibles on the ocular side. Abnormal jaws were associated with dermal papillae and a lack of pigmentation on parts of the ocular side of the head. These features are probably the result of suppressed epigenetic mechanisms normally active during ontogeny. Insights into the morphological evolution of the soleid jaw apparatus are discussed. 相似文献
99.
Jae Hee Cheon Jie‐Hyun Kim Sang Kil Lee Tae Il Kim Won Ho Kim Yong Chan Lee 《Helicobacter》2008,13(6):564-571
Background and Aim: It remains unclear whether Helicobacter pylori eradication therapy affects the healing rate of iatrogenic ulcers following endoscopic mucosal resection (EMR) for gastric tumors. The aim of our study was to prospectively evaluate the effect of H. pylori eradication therapy on gastric ulcer healing after EMR. Methods: After EMR, patients were randomly assigned to either the H. pylori eradication group (Hp group) (lansoprazole 30 mg, amoxicillin 1000 mg, and clarithromycin 500 mg, twice a day for 7 days) or the noneradication group (proton pump inhibitor, PPI group) (lansoprazole 30 mg, twice a day for 7 days). Four weeks after EMR, the ulcer stages and size were compared between the two groups. Moreover, ulcer‐related symptoms, bleeding rates, adverse effects, and drug compliance were compared. Results: A total of 64 patients were enrolled. Of these, 17 patients were excluded from the study. The two groups were comparable in terms of baseline clinicopathologic characteristics. Four weeks after EMR, the two groups did not differ with respect to ulcer stage (p = .475) or ulcer‐related symptoms (p = .399). However, the ulcer reduction ratio was significantly higher in the Hp group (0.028 ± 0.024 vs. 0.065 ± 0.055, p < .05). No differences were observed between the two groups with regard to drug compliance, adverse drug event rates, or bleeding rates. Conclusions: Our results suggest that H. pylori eradication therapy might improve the ulcer healing rate after EMR. 相似文献
100.
《DNA Repair》2017
Degradation of a 5′-ending strand is the hallmark of the universal process of DNA double strand break (DSB) resection, which results in creation of the central recombination intermediate, a 3′-ending overhang. Here we show that in Escherichia coli recB1080/recB1067 mutants, which are devoid of RecBCD's nuclease and RecA loading activities, degradation of the unwound 3′ tail is as essential as is degradation of its 5′-ending complement. Namely, a synergistic action of ExoI, ExoVII, SbcCD and ExoX single-strand specific exonucleases (ssExos) of 3′-5′ polarity was essential for preserving cell viability, DNA repair and homologous recombination in the recB1080/recB1067 mutants, to the same extent as the redundant action of 5′-tail trimming ssExos RecJ and ExoVII. recB1080 derivatives lacking 3′-5′ ssExos also showed a strong induction of the SOS response and greatly increased SOS-dependent mutagenesis. Furthermore, we show that ExoI and ExoVII ssExos act synergistically in suppressing illegitimate recombination in the recB1080 mutant but not in a wt strain, while working in concert with the RecQ helicase. Remarkably, 3′-5′ ssExos show synergism with RecQ helicase in the recB1080 mutant in all the assays tested. The effect of inactivation of 3′-5′ ssExos in the recB1080/recB1067 mutants was much stronger than in wt, recD, and recB strains. These results demonstrate that the presence of a long, reactive 3′ overhang can be as toxic for a cell as its complete absence, i.e. it may prevent DSB repair. Our results indicate that coupling of helicase and RecA-loading activity during dsDNA-end resection is crucial in avoiding the deleterious effects of a long and stabile 3′ tail in E. coli. 相似文献