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61.
62.
Background/Aims: Gallstone patients have a reduced cellular lysosome content in the gallbladder mucosa cells compared with gallstone-free subjects. The purpose of the study was to further evaluate the possible role of lysosomes in the pathogenesis of cholesterol gallstone formation in humans.Methods: Lysosomal enzyme activities were assayed in gallbladder mucosa and for comparison in liver specimens of 19 gallstone-free subjects and 24 gallstone patients undergoing cholecystectomy.Results: Gallstone patients had 25–50% lower activities of the lysosomal proteases cathepsin B, D and L in their gallbladder mucosa compared with gallstone-free subjects. The activity of acid phosphatase also tended to be decreased in gallstone patients. The liver lysosomal enzyme activities were not significantly different between the two groups.Conclusions: The results show that gallstone patients have diminished lysosomal enzyme activities in the gallbladder mucosa, a finding which may be related to decreased intracellular degradation of proteins and/or mucin in the mucosal cells. This may lead to a higher concentration of mucin in gallbladder bile and thus an increased risk of precipitation of cholesterol crystals and gallstone formation.  相似文献   
63.
为探讨痔的病因,将26例患者痔体送病理组织检查,PAS染色发现9例有紫红色菌体寄生,据其形态判断是白色念珠菌,试管沙氏培养基培养见奶白色酵母样菌落,转种于科玛嘉培养基培养见菌落呈翠绿色,诊断为白色念珠菌。由此推断痔上皮增生、角化,黏膜大量炎细胞浸润,间质水肿、出血,黏膜下静脉强烈炎性变,是因白色念珠菌感染引起的。  相似文献   
64.
This study aimed to elucidate the macroscopic and microscopic distributions of the dorsal nerve of penis (DNP) that provides the greatest sensitivity over the glans penis. The glandes of 23 penises of formalin-embalmed cadavers were investigated to confirm the macroscopic and microscopic distributions of the DNP within the glans penis by whole-mount Sihler's staining and histological sectioning. Superficial regions of the mid-glans were reconstructed in three dimensions to define the microstructure of terminal branches of the DNP that project towards the skin surface. A mean of 6.7 bundles of the DNP consisting of several nerve fibres converged linearly towards the distal end of the penis, rather than diverging laterally as they travelled. Lateral branches of the DNP extended linearly to the distal end with ramifications, while dorsomedial branches of the DNP gave off nerve fibres to the dorsum of the mid-glans and the corona. The intrastromal ramifications of the DNP were more developed in the distal half of the glans penis than the proximal glans containing the corpus cavernosum. These ramifications gave rise to radial nerve fibres that project towards the skin surface to form a plexiform network of terminal branches in the dermis. Linear projections of the main branches of the DNP throughout the glans and fine networks of terminal branches in the dermis were distinctly visualized in the human penis.  相似文献   
65.
It is now widely accepted that fatty liver disease is one of the commonest causes of cirrhosis and liver cell cancer (even in the absence of cirrhosis), in its own right as well as being an important cofactor for the progression of other diseases e.g. viral hepatitis. While much work has been done on developing non-invasive techniques for assessing liver disease, the liver biopsy remains the benchmark against which these tests have to be validated as well as providing information that cannot be obtained in any other way. This review describes the histological features that alcoholic and non-alcoholic liver disease have in common (e.g. fatty change, ballooning and Mallory–Denk bodies) as well as identifying those that are more characteristic of each of them (e.g. nuclear vacuolation in non-alcoholic fatty liver disease and a florid fatty liver hepatitis in alcoholic fatty liver disease). Recent developments in the assessment of the degree of fatty change are described.  相似文献   
66.
目的研究两种漂白剂去除牙面色斑的效果。方法使用洛贝指数和数码照像计算机色度分析,系统分析并比较实验前、后牙面洛贝指数和色斑占牙面百分比的变化。结果两种漂白剂使用2周后与空白对照组比较洛贝指数的3个指标相差显著(P<0.01);色斑占牙面百分比减小。结论两种漂白剂都能去除牙面色斑。  相似文献   
67.
牙着色即牙的外部颜色改变。国内外学者在体外建立牙的着色实验模型,探讨牙着色的影响因素,并对牙着色的清除方法作了研究。本文对相关研究的最新进展作一综述。  相似文献   
68.
本研究以可的松诱发卡氏肺孢子虫感染的大鼠与小鼠,制备肺涂片进行甲苯胺蓝染色。所有的卡氏肺孢子虫包囊均染成深紫红色,与蓝色背景易于区别。在两种肺涂片中均可见到含括号状结构的包囊,与Grocott果氏四胺银染色结果相似。一般认为该结构可以是与真菌鉴别的标志。实验结果表明甲苯胺蓝染色有可能取代银染色法,成为卡氏肺孢子虫性肺炎诊断的一种实用技术。  相似文献   
69.
70.

Background

The diagnosis of periprosthetic knee infections can present a challenge to surgeons, especially in the case of chronic presentation. Gram stains are regularly performed as part of the microbiological evaluation of suspected infected total knee arthroplasties. Recently, the utility of this test in diagnosing infections has been questioned. The purpose of this study was to assess the effectiveness of Gram stains performed from surgical site samples by comparing their results to the final diagnosis of infection.

Methods

The results of 347 Gram stains performed at a single center at the time of revision total knee arthroplasty for both septic and aseptic reasons were compared to the final diagnosis based on intra-operative findings and histological evaluation.

Results

Gram staining demonstrated a low sensitivity of 7% (95% confidence interval 4–12%), a specificity of 99% (95% confidence interval 97–100%), and positive and negative predictive values of 92% and 57%, respectively.

Conclusions

This study confirmed previous findings of the poor utility of this test for the diagnosis of periprosthetic knee infections. The authors recommend that Gram staining no longer be performed at the time of suspected periprosthetic knee arthroplasty infection.  相似文献   
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