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101.
From 1976 to June 1982, 237 patients with clinical suspicion of hepatic malignant disease underwent guided percutaneous fine-needle aspiration biopsy of the liver. Of these, 12 were diagnosed cytologically as "hepatocellular carcinoma" and this diagnosis was confirmed in the follow-up of all cases. On the basis of the cytomorphologic features observed in the aspirates, the tumor was subclassified into three types; well differentiated, pleomorphic large cell; and poorly differentiated. The various cytologic appearances of different types of hepatocellular carcinoma are presented and illustrated. Cytomorphologically, these three types of hepatocellular carcinoma were distinctly different and their cytomorphologic features were also sufficiently distinctive from those of secondary hepatic cancer to be diagnostic. Guided percutaneous fine-needle aspiration biopsy of the liver appears to be a definitive minimally invasive means of establishing the diagnosis of hepatocellular carcinoma, and promises to be a valuable diagnostic procedure for potentially resectable localized hepatocellular carcinoma.  相似文献   
102.
目的:研究一种微生物复合菌肥对穿心莲生长、品质及土壤性质的影响,旨在为穿心莲栽培生产中微生物复合菌肥的应用提供依据。方法:通过盆栽的共5个处理试验,CK(不施肥)组、A处理(施化肥)组、B处理(施微生物菌肥,施用量为2.5 g·kg-1土)组、C处理(施微生物菌肥,施用量为7.5 g·kg-1土)组、D处理(施微生物菌肥,施用量为12.5 g·kg-1土)组,研究一种复合微生物菌肥对穿心莲的农艺性状、有效成分含量及根际土壤细菌、放线菌、真菌的数量和土壤理化性质的影响。结果:施加一定量的复合微生物菌肥,穿心莲的株高、叶片数、叶面积、地上部、地下部鲜重较CK组和A处理组显著升高,不同生长期有差异。复合微生物菌肥对穿心莲内酯、脱水穿心莲内酯、新穿心莲内酯及14-去氧穿心莲内酯含量影响有差异,与CK组、A处理组比较,C处理组的穿心莲内酯分别明显升高26.13%、13.23%(P<0.05);新穿心莲内酯的含量随微生物菌肥施加量的增加而增加,在D处理组下的效应最显著,与CK组、A处理组比较,分别明显升高9.06%、50.33%(P<0.05);B处理组的14-去氧穿心莲内酯较A处理组...  相似文献   
103.
Globally, many countries are facing an increasing burden of chronic disease due to ageing populations, of which cardiovascular disease forms a large proportion. Excess dietary sodium contributes to cardiovascular disease risk and requires intervention at a population level. This study aimed to quantify the impact of several salt reduction initiatives on population health over a 30-year horizon using GeoDEMOS, a population model from Singapore. Four interventions were modelled in four demographic groups in 2020 for a total of 16 intervention scenarios. The effect of 0.5, 2.0, and 4.0 g/day reductions in daily salt consumption, along with adherence to the World Health Organization guidelines of a maximum of 5.0 g of salt each day, was modelled in the entire population, including the overweight and obese, the elderly, and diabetics. In each scenario, the number of averted incident cases of acute myocardial infarction and stroke, along with the disability-adjusted life years up to 2050, was monitored. We found 4.0 g/day reductions in salt consumption were the most effective when implemented across the entire population, resulting in 24,000 averted incident cases of cardiovascular disease and 215,000 disability-adjusted life years over 30 years. This is a large figure when compared with the 29,200 projected annual incident cases of cardiovascular disease in 2050. When targeted at specific high-risk demographic groups, the largest effects were observed in the overweight and obese, with the same intervention yielding 10,500 averted incident cases of cardiovascular disease and 91,500 disability-adjusted life years. Quantifying the benefits of salt reduction initiatives revealed a significant impact when administered across the entire population or the overweight and obese. Health promotion efforts directed toward sustainably reducing salt consumption will help to lower the chronic disease burden on the healthcare system in years to come.  相似文献   
104.
105.
目的验证JOA X-线骨质疏松诊断标准的可靠性.方法47名女性病人(年龄65.3±7.2岁)行腰椎常规X-线检查和第三腰椎正、侧位DEXA骨密度测量.用t检验验证X-线骨质疏松等级间骨密度的差异性,用Spearman相关性分析法检验X-线骨质疏松等级与骨密度值的相关性.结果X-线骨质疏松等级间骨密度具有显著性差异(P<0.01),X-线骨质疏松等级与第三腰椎侧位骨密度值之间相关性最高(r=0.714).结论通过腰椎X-线片按照JOA标准划分骨质疏松等级,可以作为粗略检查腰椎骨质疏松的方法.  相似文献   
106.
目的:观察中药解郁胶囊对老年抑郁症的临床疗效和安全性。方法:选取2020年11月至2021年12月甘肃中医药大学附属医院住院或门诊患者200例作为研究对象,按照纳入标准最终产生研究观察对象100例,健康对照组来自我院组织的年龄在60~80岁的健康体检的老年人100例。观察组中男37例,女63例,对照组中男43例,女57例。对照组采取常规治疗,观察组采取中医综合疗法治疗。对2组患者治疗前后减分情况、中医证候分析、服药及依从情况、不良反应及抑郁焦虑因子等无创性指标的影响。结果:对老年抑郁症的治疗效果主要从汉密尔顿抑郁量表减分情况及证候减分率体现,2组经过12个月中药和抗抑郁综合治疗,中医证候量表减分率(8.2±3.1)和(7.8±3.2),比对照组的(8.8±3)与(8.4±3.6),P值为0.001 6和0.001 3,治疗前后均有明显变化,差异有统计学意义(P<0.05),中医证候量表减分率比较,差异有统计学意义(P<0.05),从服药后出现的不良反应来看,中医综合观察组应明显低于对照观察组,差异有统计学意义(P<0.05)。从中医组治疗患者的依从性分析,差异有统计学意义(P<0.05)。结论:中药解郁胶囊与中医综合治疗患者治疗效果显著,依从性更佳。  相似文献   
107.
目的探究动态增强磁共振成像(DCE-MRI)用于评估女性乳房乳头乳晕血供特点的可行性,为乳房整形手术提供乳头乳晕的血供参考。方法从2012年3月至2019年10月华中科技大学同济医学院附属同济医院影像数据库中收集女性乳腺DCE-MRI图像资料,选择未发现肿物的正常乳房的DCE-MRI图像进行研究。在西门子工作站将患者乳腺DCE-MRI图像通过图像减影获取乳房血管图像,分别对轴位、冠状位和矢状位的最大密度投影(MIP)图像进行评估,结合三维MIP图像识别所有供应乳头乳晕的血管。乳头乳晕的血供被划分为内上、内侧、内下、外上、外侧、外下、中央、上方和下方9个象限,对各个象限血管进行统计和分析,并测量血管至乳房皮肤表面投影的最大距离。采用SPSS 19.0软件进行统计分析,通过卡方检验分别比较左侧与右侧乳房的乳头乳晕复合体(NAC)血供象限分布构成比。计算血管到皮肤距离的平均值、标准差及95%置信区间,通过方差分析比较各象限血管至皮肤距离的差异。P<0.05为差异具有统计学意义。结果共收集到245例患者490只女性乳房DCE-MRI图像,其中97例患者97只乳房发现有乳腺肿物,其余393只为正常乳房(97例单侧乳房、148例双侧乳房),将其作为研究对象。患者年龄23~72岁,平均43.7岁。393只乳房(左侧200只、右侧193只)共发现有637条(左侧311条、右侧326条)乳头乳晕供应血管。在637条血管中,内上象限269条(42.2%),外上180条 (28.3%),内侧57条(8.9%),下方37条(5.8%),中央30条(4.7%),内下25条(3.9%),外下25条(3.9%),上方11条(1.7%),外侧3条(0.5%)。卡方检验表明左侧乳房和右侧乳房在NAC血供象限分布构成比差异无统计学意义(χ2 =6.4,P=0.602)。除中央象限血管以外,所有血管到皮肤表面投影最大距离的平均值为0.91 cm, 95%置信区间为0.86~0.96 cm。方差分析表明各象限供血血管到皮肤投影的最大距离,差异有统计学意义(F=11.4,P<0.001)。结论 DCE-MRI可以清晰地显示乳头乳晕的血供来源。乳头乳晕血供主要来源于内上象限和外上象限的血管,血管在皮下约1 cm深度走行。  相似文献   
108.
109.

Although the carbendazim is widely used to manage spot blight in celery cultivation, information on residues identified is of interest. In this study, we examined the dissipation and residual amounts of carbendazim in celery and soil under different cultivation methods when using the suggested dose and ten times of that and the bioconcentration factor of carbendazim for celery. The results showed that when celery leaves were sprayed with the suggested dose, the half-lives in a celery field and greenhouse were 2.75 days and 3.29 days, respectively. When the soil matrix was sprayed with the recommended dose before cultivation, the half-lives of carbendazim residues were 16.86 days and 11.97 days. We also conducted a long-term dietary risk assessment using the corresponding criteria. The results showed that, in China, the use of carbendazim at a dose of 0.022 g/m2 is safer and more reasonable when the harvest interval is 28 days.

  相似文献   
110.
Ni M  Ratner BD 《Biomaterials》2003,24(23):4323-4331
Nacre, also known as mother-of-pearl, constitutes the inner layer of mollusc shells. Nacre is a natural composite material consisting mostly of calcium carbonate in the aragonite crystal form and some organic matter. Previous studies have shown that geological aragonite, coral and nacre can convert hydrothermally to hydroxyapatite (HAP) in phosphate solution by a solid-state topotactic ion-exchange reaction. This conversion typically occurs within the range of 140-260 degrees C, although higher temperatures are possible. In this work, we have found that nacre can transform to HAP in a phosphate buffer solution at room temperature via a surface reaction. The morphology of the nacre-transformed HAP surface was investigated by scanning electron microscopy (SEM). The HAP surfaces were characterized by X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS). A layer covered with packed particles was found in contrast to the tablet structure typical of nacre surfaces. XPS and SIMS indicated that the mineral phase of the nacre surface had converted from an aragonite phase to an HAP phase. Fourier transform infrared spectroscopy (FTIR) showed that phosphate (PO(4)) bands appeared after nacre was soaked in a phosphate buffer and the intensity of the PO(4) bands increased with exposure time. The FTIR was consistent with XPS and SIMS results. We suggest that this surface reaction occurs by a dissolution-precipitation mechanism. Calcium ions are released from the nacre surface, react with phosphate ions in the buffer solution, and then precipitate as HAP on the nacre surface.  相似文献   
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