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41.
角膜散光由角膜前表面散光(anterior astigmatism,AA)和角膜后表面散光(posterior astigmatism,PA)组成。据文献统计,PA在-0.01~-1.10 D范围内,85.0%~96.1%为逆规散光。随着年龄的增长,PA总体呈现由逆规向顺规漂移的趋势,AA的趋势则与之相反。因此,对于青年人,PA使总角膜散光(total astigmatism,TA)减小;对于老年人,PA使TA增大。在临床上,忽略PA会错误估计TA,影响屈光性白内障手术后的视觉质量。本文旨在介绍PA的测量方法及临床意义,以供眼科医生在临床工作中参考。  相似文献   
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《Immunity》2021,54(8):1728-1744.e7
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BackgroundIncreasing prevalence of overweight and obesity represents a global pandemic. As the largest occupational group in international healthcare systems nurses are at the forefront of health promotion to address this pandemic. However, nurses own health behaviours are known to influence the extent to which they engage in health promotion and the public's confidence in advice offered. Estimating the prevalence of overweight and obesity among nurses is therefore important. However, to date, prevalence estimates have been based on non-representative samples and internationally no studies have compared prevalence of overweight and obesity among nurses to other healthcare professionals using representative data.ObjectivesTo estimate overweight and obesity prevalence among nurses in Scotland, and compare to other healthcare professionals and those working in non-heath related occupations.DesignCross-sectional study using a nationally representative sample of five aggregated annual rounds (2008–2012) of the Scottish Health Survey.SettingScotland.Participants13,483 adults aged 17–65 indicating they had worked in the past 4 weeks, classified in four occupational groups: nurses (n = 411), other healthcare professionals (n = 320), unqualified care staff (n = 685), and individuals employed in non-health related occupations (n = 12,067).Main outcome measuresPrevalence of overweight and obesity defined as Body Mass Index  25.0.MethodsEstimates of overweight and obesity prevalence in each occupational group were calculated with 95% confidence intervals (CI). A logistic regression model was then built to compare the odds of being overweight or obese with not being overweight or obese for nurses in comparison to the other occupational categories. Data were analysed using SAS 9.1.3.Results69.1% (95% CI 64.6, 73.6) of Scottish nurses were overweight or obese. Prevalence of overweight and obesity was higher in nurses than other healthcare professionals (51.3%, CI 45.8, 56.7), unqualified care staff (68.5%, CI 65.0, 72.0) and those in non-health related occupations (68.9%, CI 68.1, 69.7). A logistic regression model adjusted for socio-demographic composition indicated that, compared to nurses, the odds of being overweight or obese was statistically significantly lower for other healthcare professionals (Odds Ratio [OR] 0.45, CI 0.33, 0.61) and those in non-health related occupations (OR 0.78, CI 0.62, 0.97).ConclusionsPrevalence of overweight and obesity among Scottish nurses is worryingly high, and significantly higher than those in other healthcare professionals and non-health related occupations. High prevalence of overweight and obesity potentially harms nurses’ own health and hampers the effectiveness of nurses’ health promotion role. Interventions are therefore urgently required to address overweight and obesity among the Scottish nursing workforce.  相似文献   
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Two patients with cardiac metastasis from head and neck cancer are reported. Cardiac metastasis located in the left atrium was detected on a follow-up computed tomography (CT) scan 15 months after partial glossectomy for a tongue carcinoma in a 60-year-old man. The diagnosis was confirmed as cardiac metastasis of squamous cell carcinoma (SCC) by surgical excision of the cardiac lesion. The patient died 3 weeks after surgery. In a 69-year-old man with a partial maxillectomy for primary soft palate cancer, a follow-up CT scan 5 months after surgery revealed a mass in the right atrium and ventricle, and multiple lung metastases. He died of heart failure 3 weeks after the diagnosis of cardiac metastasis. Information on these cases should add to knowledge about rarely encountered cardiac metastasis.  相似文献   
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The pathological changes of parasympathetic nerve are considered as an independent prognostic factor of the survival rate of patients with chronic liver disease. The non-selective muscarinic acetylcholine receptors (mAchR) agonists and antagonists can affect the proliferation of hepatocytes and hepatic stellate cells, but the subtypes of mAchR expressions in HCs are still uncertain. Here, we investigate the expression of mAchR in hepatic fibrosis on rats. 3 ml/kg 40% carbon tetrachloride (CCL4) was given to induce hepatic fibrosis on rats and the hepatocytes were isolated. Compared to the normal state, the expression levels of m1, 3, 5 in fibrotic liver tissues or hepatocytes were obviously increased, while m2, 4 decreased. 10 μM pilocarpine or 10 μM acetylcholine could increase the alanine aminotransferase (ALT), hydroxyproline (Hyp), collagen I, III in the hepatocytes, and decreased albumin (ALB). They also changed the expressions of mAchR similarly as the fibrotic hepatocytes and livers. However, atropine could ameliorate the state of fibrotic hepatocytes. These data indicate that mAchR played an important role in the regulation of hepatic fibrosis process. Targeting mAchR would have therapeutic potential for hepatic fibrosis.  相似文献   
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目的:比较缬沙坦和卡托普利对心肌纤维化及超微结构改变的干预作用。方法:14周龄自发性高血压大鼠(SHR)25只随机分为5组:缬沙坦组(SHRv)、卡托普利组(SHRc)、卡托普利组 缬沙坦组(SHRc v)、假治对照组(SHR20)和高血压基础对照组(SHR14)。同周龄SD大鼠5只设为正常对照组(SD20)。疗程为6周。处死后测算左室重量/体重比(LVM/BW)、光镜观察心肌胶原分布,测算胶原容积分数(CVF)、血管周围胶原面积/管腔面积比(PVCA/LA)和组织匀浆胶原浓度,电镜观察心肌超微结构改变。结果:三个治疗组反映心肌纤维化的多项指标均较SHR20和SHR14组显著改善(P<0.0l&0.05)。SHRv与SHRc v组的改善相似,均优于SHRc组(P<0.05),但仍差于SD20组(P<0.05)。心肌超微结构改变均较SHR20组显著好转。结论:缬沙坦和卡托普利均能抑制高血压心肌纤维化及超微结构改变,但短期治疗不能恢复正常。缬沙坦的作用优于卡托普利,两者联用优于单用卡托普利,但并不显著优于单用缬沙坦。  相似文献   
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目的总结胸腔镜下二尖瓣心脏外科手术的体外循环(CPB)管理经验和方法。方法 2013年1月-2017年6月80例胸腔镜下二尖瓣置换术,CPB采用中、浅低温,全部采用股动静脉插管,并在CPB中予以负压辅助静脉吸引,术中全部采用HTK液灌注心肌予以心肌保护,对CPB建立方法、CPB过程及手术后结果进行评价。结果 80例心脏二尖瓣疾病患者全部予以痊愈出院。全部患者CPB转流时间为97~308(192.2±54.2)min;升主动脉阻断时间为50~233(130.8±46.9)min;辅助转流时间为30~53(41.8±8.1)min。术后呼吸辅助时间6~24(20.6±14.1)h;术后ICU时间为2~6(3.3±2.6)d;术后住院时间7~10 d;术中及术后无股动静脉插管相关并发症,患者术后均恢复良好,脱机良好,无严重并发症。出院随访时间3~12个月,结果满意。结论胸腔镜下二尖瓣手术中,CPB方法安全、可行,开展此手术的初期CPB时间和主动脉阻断时间较传统手术时间较长,应加强CPB的管理,避免术中术后产生CPB相关性并发症。  相似文献   
50.
Apoptosis of human pancreatic cancer cells induced by Triptolide   总被引:4,自引:0,他引:4  
AIM: To investigate apoptosis in human pancreatic cancer cells induced by Triptolide (TL), and the relationship between this apoptosis and expression of caspase-3' bcl-2 and bax. METHODS: Human pancreatic cancer cell line SW1990 was cultured in DMEM media for this study. MTT assay was used to determine the cell growth inhibitory rate in vitro. Flow cytometry and TUNEL assay were used to detect the apoptosis of human pancreatic cancer cells before and after TL treatment. RT-PCR was used to detect the expression of apoptosis-associated gene caspase-3' bcl-2 and bax. RESULTS: TL inhibited the growth of human pancreatic cancer cells in a dose-and time-dependent manner. TL induced human pancreatic cancer cells to undergo apoptosis with typically apoptotic characteristics. TUNEL assay showed that after the treatment of human pancreatic cancer cells with 40 ng/mL TL for 12 h and 24 h, the apoptotic rates of human pancreatic cancer cells increased significantly. RT-PCR demonstrated that caspase-3 and bax were significantly up-regulated in SW1990 cells treated with TL while bcl-2 mRNA was not. CONCLUSION: TL is able to induce the apoptosis in human pancreatic cancer cells. This apoptosis may be mediated by up-regulating the expression of apoptosisassociated caspase-3 and bax gene.  相似文献   
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