表观扩散系数值与肝细胞癌分级的相关性以及相关性与肿瘤大小关系的分析

[摘要]　目的　探讨表观扩散系数（apparent diffusion coefficient, ADC）值与肝细胞癌（hepatocellular carcinoma, HCC）组织学分级的相关性以及不同直径肿瘤的ADC值与HCC的相关性。方法?回顾性分析2017年—2020年180例病理证实为HCC的病例资料,按肿瘤直径大小分为＜2 cm、≥2 cm且＜3 cm、≥3 cm且＜5 cm、≥5 cm 4组,标为I、II、III、IV组。分析ADC值与HCC组织学分级的相关性,并分析在不同直径肿瘤ADC值与HCC的相关性。结果?高、中和低分化HCC的ADC值分别为（1.159±0.302）×10-3、（0.951±0.213）×10-3和（0.811±0.239）×10-3 mm2/s,逐级降低（P＜0.05）。ADC值与总体HCC的组织学分级呈负相关（r=-0.474）,与I～III组HCC的组织学分级均呈负相关（r值分别为-0.663、-0.527、-0.364）,而与IV组HCC的组织学分级无相关性。结论?ADC值可以作为非侵入性预测HCC组织学分级的指标,预测结果受肿瘤大小影响,更适用于小肝细胞癌。     

Research and Evaluation of the Influence of the Construction of the Gate and the Influence of the Piston Velocity on the Distribution of Gases into the Volume of the Casting

Distribution of gasses to the cast volume and volume of pores can be maintained within the acceptable limits by means of correct setting of technological parameters of casting and by selection of suitable structure and gating system arrangement. The main idea of this paper solves the issue of suitability of die casting adjustment—i.e., change of technological parameters or change of structural solution of the gating system—with regards to inner soundness of casts produced in die casting process. Parameters which were compared included height of a gate and velocity of a piston. The melt velocity in the gate was used as a correlating factor between the gate height and piston velocity. The evaluated parameter was gas entrapment in the cast at the end of the filling phase of die casting cycle and at the same time percentage of porosity in the samples taken from the main runner. On the basis of the performed experiments it was proved that the change of technological parameters, particularly of pressing velocity of the piston, directly influences distribution of gasses to the cast volume.     

缺锌对孕鼠生长发育及其肝脏、胎盘中谷胱甘肽过氧化物酶及过氧化氢酶活性的影响

为观察喂养缺锌饲料对孕鼠生长发育及其肝脏、胎盘中谷胱甘肽过氧化物酶(GSH-PX)及过氧化氢酶(CAT)活性的影响。将16只受孕Wistar鼠随机分为缺锌组(ZD组)、加锌组(ZS组)和正常对照组(ZC组),分别喂饲缺锌饲料、加锌饲料和基础饲料,记录每只孕鼠每日体重变化。于妊娠21日将孕鼠处死,取其肝脏、胎盘作GSH-PX和CAT活性测定。结果为ZD组孕鼠体重未见增加,SC组和ZS组孕鼠体重增加明显;与ZC组和ZS组相比,ZD组孕鼠肝脏和胎盘中GSH-PX活性显著降低(P<0.05),孕鼠肝脏和胎盘中CAT活性显著升高(P<0.05)。故认为缺锌可影响孕鼠肝脏、胎盘中谷胱甘肽过氧化物酶及过氧化氢酶活性,并影响其生长发育。     

Ligaments of the larynx and the adjacent pharynx and esophagus

Two ligament systems of the larynx are demonstrated by dissection. The suspensory ligament of the esophagus is attached to the posterior aspect of the cricoid cartilage and is also a part of the fascial sheath which is common to the hyoid, thyroid, and cricoid. The ligaments at the inner margins of the vocal, ventricular, and aryepiglottic folds are distinctive in site and, inferentially, in function. The aryepiglottic ligaments join at the incisura between the arytenoid cartilages and are continued as the corniculopharyngeal ligament which splays into the flexible tissues in the anterior wall of the hypopharynx, posterior to the suspensory ligament of the esophagus. These ligament systems are involved in two different actions in swallow. The gross superior and anterior motions of the larynx are transmitted to the esophagus by the suspensory ligament, so that the esophagus is elevated in relation to the bolus and is also opened. These esophageal displacements resemble, in effect, the swallow displacements of the pharyngoesophageal segment and of the constrictor wall of the hypopharynx. The marginal ligaments of the laryngeal folds help to implement the constriction and closure of the larynx during swallow. By anatomical inference, the corniculopharyngeal ligament effects vertical traction within the flexible tissues of the anterior wall of the hypopharynx.     

Humanism and the suffering of the people

Abstract
Humanism includes, among its many contexts, the ideal of the universal perfection of health. Procedures for alleviation of disease existed through all epochs of human history, but efficacy was mostly lacking. The prototypic humanism of the Renaissance ( ad  1300−1600) scarcely involved the medical ­sciences other than human anatomy. The Enlightenment of the seventeenth century included discovery of the circulation of the blood, and applications of microscopy. Discoveries relevant to medical practice began in the nineteenth century, ushered in by vaccination and the germ theory of disease. This 200-year period saw a transformation of human health according to the surrogate marker of increased life-­expectancy. This has been variously attributed to: (i) increased prosperity following the industrial revolution, (ii) efforts of humanistic social and public health reformers and, more recently, (iii) advances in medical science. Yet the beneficiaries remain a minority of the world's population. The nexus between poverty, illness and low life-expectancy between and within nations is the major challenge for the future. Contemporary science is providing ever-expanding knowledge on means to achieve the goal of perfection of human health, but the need for humanism is as great as at any previous age. Fortunately, however, the targets are more clearly visible than during the periods of poverty, plagues and pestilence of the past. (Intern Med J 2003; 33: 195−202)     

特应性与非特应性哮喘的发病机制研究

目的研究炎症细胞及其相关细胞因子、炎性介质在哮喘发病中的作用及相互关系，探讨特应性与非特应性哮喘的发病机制。方法对36例哮喘患者和12例健康者（对照组）进行痰液诱导，对其痰液中的中性粒细胞、嗜酸粒细胞数及白介素4（IL-4）、IL-5、IL-8、髓过氧物酶（MPO）进行检测。结果哮喘组中重度患者痰液中嗜酸粒细胞和中性粒细胞数均高于轻度患者及对照组。IL-4和IL-8水平除缓解期患者与对照组比较无统计学差异外，其余均有统计学意义（P〈0．05）。哮喘组中重度患者MPO与其余比较有统计学差异；哮喘组轻度患者与对照组比较统计学差异显著（P〈0．01）。结论特应性哮喘的发病机制与诱导痰中嗜酸粒细胞数相关；非特应性哮喘与中性粒细胞数相关。     

On the evolution of chaperones and cochaperones and the expansion of proteomes across the Tree of Life

Across the Tree of Life (ToL), the complexity of proteomes varies widely. Our systematic analysis depicts that from the simplest archaea to mammals, the total number of proteins per proteome expanded ∼200-fold. Individual proteins also became larger, and multidomain proteins expanded ∼50-fold. Apart from duplication and divergence of existing proteins, completely new proteins were born. Along the ToL, the number of different folds expanded ∼5-fold and fold combinations ∼20-fold. Proteins prone to misfolding and aggregation, such as repeat and beta-rich proteins, proliferated ∼600-fold and, accordingly, proteins predicted as aggregation-prone became 6-fold more frequent in mammalian compared with bacterial proteomes. To control the quality of these expanding proteomes, core chaperones, ranging from heat shock proteins 20 (HSP20s) that prevent aggregation to HSP60, HSP70, HSP90, and HSP100 acting as adenosine triphosphate (ATP)-fueled unfolding and refolding machines, also evolved. However, these core chaperones were already available in prokaryotes, and they comprise ∼0.3% of all genes from archaea to mammals. This challenge—roughly the same number of core chaperones supporting a massive expansion of proteomes—was met by 1) elevation of messenger RNA (mRNA) and protein abundances of the ancient generalist core chaperones in the cell, and 2) continuous emergence of new substrate-binding and nucleotide-exchange factor cochaperones that function cooperatively with core chaperones as a network.

All cellular life is thought to have stemmed from the last universal common ancestor (LUCA) (1, 2), that emerged more than 3.6 billion y ago. Two major kingdoms of life diverged from LUCA: bacteria and archaea, which about 2 billion y later merged into the eukaryotes (3). Since the beginning of biological evolution, life’s volume has increased on a grand scale: The average size of individual cells has increased ∼100-fold from prokaryotes to eukaryotes (4), the number of cell types has increased ∼200-fold from unicellular eukaryotes to humans (5), and average body size has increased ∼5,000-fold from the simplest sponges to blue whales (6).This expansion in organismal complexity and variability was accompanied by an expansion in life’s molecular workforce, proteomes in particular, which in turn presented a challenge of reaching and maintaining properly folded and functional proteomes. Most proteins must fold to their native structure in order to function, and their folding is largely imprinted in their primary amino acid sequence (7–9). However, many proteins, and especially large multidomain polypeptides, or certain protein types such as all-beta or repeat proteins, tend to misfold and aggregate into inactive species that may also be toxic (10). Life met this challenge by evolving molecular chaperones that can minimize protein misfolding and aggregation, even under stressful out-of-equilibrium conditions favoring aggregation (11, 12). Chaperones can be broadly divided into core and cochaperones. Core chaperones can function on their own, and include ATPases heat shock protein 60 (HSP60), HSP70, HSP100, and HSP90 and the adenosine triphosphate (ATP)-independent HSP20. The basal protein holding, unfolding, and refolding activities of the core chaperones are facilitated and modulated by a range of cochaperones such as J-domain proteins (13–15).Starting from LUCA, as proteomes expanded, so did the core chaperones and their respective cochaperones. Indeed, chaperones have been shown to facilitate the acquisition of destabilizing mutations and thereby accelerate protein evolution (16–18). However, the coexpansion of proteomes and of chaperones, underscoring a critical balance between evolutionary innovation and foldability, remains largely unexplored. We thus embarked on a systematic bioinformatics analysis that explores the evolution of both proteomes and chaperones, and of both core and their auxiliary cochaperones, along the Tree of Life.     

Preservation of the pylorus and resection of the head of the pancreas

The historical evolution of the pylorus-preservation resection of the head of the pancreas is traced from the first resections early in this century to relative standardization of the operation, to a lowering of the operative mortality, and to an interest in improving nutritional status after resection. There are many theoretical advantages for the function of the upper gastrointestinal tract after pylorus and gastric preservation, such as maintenance of gastric capacitance and equilibration of osmotic pressure in gastric digestants, foodstuff digestion and absorption, and bowel motility. After the pylorus-preserving resection, gastric emptying is normal, pyloric function to prevent duodenal reflux is often normal, and gastric acids and serum levels of duodenal hormones are at normal levels, whereas after standard pancreatoduodenectomy, all of these are often abnormal. No prospective blinded studies have been published comparing nutritional values after the two operative procedures, but evidence is presented of a satisfactory result with regard to gastric capacitance, body weight gain, and lack of postgastrectomy symptoms. An undoubted advantage of the pylorus-preserving feature is a simplification of the operation. These gains are achieved without increase in operative mortality, without increase in the incidence of jejunal ulcer, and without theoretical or actual decrease in value of the procedure as a cancer operation, except in patients with duodenal carcinoma proximal to the ampulla of Vater.     

浅谈抗生素及其合理使用的管理

目的探讨我国临床中抗生素使用与致病菌耐药的因果关系。方法综合分析困内外抗生素使用情况及耐药菌发展趋势。结果由于诸多因素所导致的抗生素滥用现象非常普遍，抗生素药物的总体使用率偏高，大约70％～80％，耐药菌种类日趋增多。结论有必要对抗生素的使用进行规范，围绕着抗生素的合理使用制订出“抗生素应用政策”，并采取一定的措施和干预手段，使这一政策有效的贯彻和实施。     

Ceramide and the regulation of apoptosis and the stress response

The process of apoptosis or programmed cell death has been the subject of intense study due to the realization of its importance in a wide variety of biological and pathological conditions, including development, ischemia, cancer, and neurodegenerative disorders. Although a vast number of inducers of this process and several critical components have been identified, the signal transduction pathways regulating apoptosis are poorly understood. Recently, a pathway involving sphingolipid turnover and the production of the lipid mediator, ceramide, has emerged as a candidate regulator of apoptosis. This review provides a summary of the evidence implicating ceramide as a mediator of apoptosis and the stress response. (Trends Cardiovasc Med 1996;6:158-162).     

Structure and physiology of the pleura and the pleural space

The pleural space, derived from the intraembryonic coelom, is limited by a serous membrane including the mesothelium formed by cells possessing not only the characteristic features of epithelial cells but also the potential of secretory cells (cytokines and growth factor). Blood supply to visceral pleurae differs depending on the species while the lymphatic circulation is directly connected to the pleural space via pores in the parietal pleura. Pleural physiology and movement of pleural fluid are directly related to the particular structures of the pleura.     

Distribution of oxyntomodulin and glucagon in the gastrointestinal tract and the plasma of the rat

Oxyntomodulin (OXM), an intestinal glucagon-containing peptide extended at its C-terminal end by an octa-peptide, is one of the gut glucagon-like immunoreactants (GLI) or enteroglucagon. The distribution of OXM and glucagon was determined in the gastrointestinal tract and in the plasma of the rat. Reversed-phase HPLC, associated with RRA or RIA, performed with an N-terminally directed glucagon antiserum (GOL), was used. HPLC of intestinal extracts or plasma separated the GOL immunoreactivity into three peaks: two major peaks coeluting with a preparation of rat glicentin (peak I, partially purified from rat intestine) and porcine or rat OXM, respectively, and a smaller peak coeluting with glucagon. The behavior of the three peaks in the analytical systems matched that of glicentin, OXM, and glucagon, respectively, allowing their identification. The concentrations of OXM picomoles per g of tissue) gradually increased from the duodenum (9 +/- 1) to ileum (93 +/- 4), thereafter decreasing in cecum and colon (22 +/- 3). In the gut, OXM, glucagon, and peak I averaged 40%, 1%, and 59% of the total GLI, respectively. OXM was present in significant amounts in the pancreas (18% of GLI) and stomach (27% of GLI), two tissues in which it accounted, together with glucagon, for almost the totality of GLI. In 24 h-fasted rats, plasma concentrations of OXM, glucagon, and peak I, determined after HPLC with GOL antiserum, were 15.1 pM, 8.6 pM, and 12.3 pM, respectively. Two hours after refeeding, both OXM and peak I were significantly increased (P less than 0.05 and P less than 0.02) by a similar factor (2-fold), while glucagon remained unchanged. When the HPLC results were compared with RIA measurement of GLI (GOL antiserum) and glucagon (with a C-terminal glucagon antiserum) in plasma, enteroglucagon (GOL--C-terminal glucagon antiserum immunoreactivities) correlated well with the sum of OXM plus peak I. The combination of HPLC and RRA or RIA allows the unambiguous determination of OXM, glucagon, and glicentin (peak I) in tissues and plasma. In the rat intestine and in the plasma, OXM and glicentin appear roughly in the same ratio and seem to be the major components, if not the totality, of enteroglucagon.     

Acid and alkaline phosphatases of the rat prostate and the androgenic status of the body

A study was made of the activity of acid and alkaline phosphatases in the prostate of rats with disorders of the hormonal status induced by gonadectomy followed by injection of testosterone and its metabolite, 5 alpha-dihydrotestosterone in order to define specific functional indices, enabling gonadal androgenic function to be assessed. The activity of both prostatic phosphomonoesterases decreased after gonadectomy and rose after the substituting injection of the androgen. The efficacy of the androgens was to a great degree dependent on the dosage, duration of the drug action, and animals' age. The data obtained indicate that the activity of the phosphomonoesterases depends on androgenic saturation of the body and that both acid and alkaline phosphatases may serve as markers of androgenic activity.