肾性骨病的骨膜下骨吸收

笔者采用手骨直接Ｘ线放大摄影和双手Ｘ线平片来研究慢性肾衰血透病人５１例。特征性的指骨骨膜下吸收放大摄影发现２５例占４９％;平片为１１例占２１．６％,结果表明,放大摄影的阳性率明显高于平片（Ｐ＜０．００５）,骨膜下吸收的二,三指中间指骨桡侧及指骨末端是肾性骨病的“靶区”,认为二者无显著差异（Ｐ＞０．５０）。骨膜下吸收还与血透时间,血磷,血钙和碱性磷酸酶水平相关。     

Hydrolysis kinetics of metampicillin by high performance liquid chromatography

The hydrolysis of metampicillin to ampicillin was investigated using high performance liquid chromatography. We developed the simultaneous determination of metampicillin and ampicillin using a Zorbax CN column and 5% acetonitrile and 8% methanol in 0.02 M phosphate buffer (pH 7.0) as mobile phase. Metampicillin was hydrolyzed to ampicillin with half life of 41.5 min at physiological pH and temperature. In acidic pH, metampicillin was rapidly hydrolyzed to ampicillin within a chromatographic separation.     

Epimerization and Hydrolysis of Dalvastatin,a New Hydroxymethylglutaryl Coenzyme A (HMG-CoA) Reductase Inhibitor

In aqueous solutions, dalvastatin (1) undergoes epimerization as well as hydrolysis. The transformation of the drug was studied as a function of pH at 25°C in aqueous solutions containing 20% acetonitrile. At all pH values, first-order plots for the conversion are biphasic, indicating rapid equilibration of 1 with its epimer (2) and slower hydrolysis of 1 to the corresponding -hydroxy acid (3). Apparent first-order rate constants for the biexponential equation are given as a function of pH. The alkyl–oxygen cleavage of the lactone ring results in the epimerization of 1 to 2, whereas the acyl–oxygen cleavage results in the hydrolysis of 1 to 3. The epimerization is an S_N1 reaction reaching an equilibrium of [l] _eq/[2] _eq = 1.27. The epimerization rate is increased with an increase in the water content of the solvent. The hydrolysis of 1 to 3 is acid and base catalyzed. The hydrolysis is reversible in acidic media and irreversible in neutral and basic media. At pH values greater than 9, the hydrolysis reaction proceeds more rapidly than the epimerization.     

Microdissection and microcloning of chromosomal alterations in human breast cancer

Summary The recognition of recurring sites of chromosome changes in malignancies has greatly facilitated the identification of genes implicated in the pathogenesis of human cancers. Based especially upon recent studies [1–4], it appears increasingly likely that a subset of recurring chromosome alterations will be recognized in human breast cancer. Currently recognized chromosome changes characterizing breast carcinoma include the recognition of cytologic features of gene amplification (e.g. double minutes [dmins] and homogeneously staining regions [HSRs]) [5–8]. As these and other chromosome regions are implicated in recurring abnormalities in breast cancer, it will become increasingly important to have band-or region-specific genomic libraries and probes in order to facilitate high resolution physical mapping and ultimately to clone breast cancer related genes [9]. Toward this end an important recent development in physical mapping has been the establishment of chromosome microdissection as a rapid and reproducible approach to rapidly isolate and characterize chromosome region-specific DNA, greatly facilitating the initial steps in positional cloning of disease-related genes [10–13]. In this brief report, we will highlight the application of chromosome microdissection to the generation of region-specific probes for both fluorescent in situ hybridization (FISH) and the generation of genomic microclone libraries. Additionally, efforts using this methodology to generate a microclone library encompassing the early onset breast/ovarian cancer (BRCA1) gene will be presented.Presented by Jeffrey M. Trent at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer.     

Varus deformity of the distal end of the femur secondary to a focal fibrous lesion

Severe unilateral varus deformity of the distal end of the femur secondary to a focal fibrous lesion is reported. It is a malformative process rare at this level, this being the first report of it in the radiological literature. The conventional radiograph is pathognomonic and CT is useful in the confirmation of the fibrous tissue. Osteotomy is indicated only if the deformity progresses or the angle of varus is severe.     

臂丛下干的应用解剖观察

目的了解斜角肌间隙内臂丛下干与邻近组织结构及胸１神经干与第１肋的关系,为临床诊治臂丛下干卡压症提供解剖学依据。②方法在２１具４２侧成人标本上观测臂丛下干与邻近结构的位置关系。③结果在４２侧标本的斜角肌间隙内,有３３侧在前斜角肌的后内侧存在孤立的肌束,臂丛下干分别从其前下方（２３侧）或后上方（１０侧）通过;组成臂丛下干的胸１神经干在斜越第１肋前内侧面时部分穿行于骨纤维管内。④结论该肌束的压迫或拱抬均可成为臂丛下干受压的因素之一;组成臂丛下干的胸１神经干在越过第１肋时易受压迫。     

英脱利匹特增强超声多普勒血流信号作用的实验研究

目的：研究英脱利匹特增强超声多普勒血流信号的作用。方法：在１０ 只兔中应用经颅超声多普勒检测静脉推注４ 种不同剂量（０ ．２、０．５、１．０、２．０ｍｌ／ｋｇ）２０ ％ 英脱利匹特前后的动脉血流信号,并以等量的生理盐水作对照。结果：各种剂量２０ ％ 的英脱利匹特注射后多普勒血流信号强度明显增强, 平均比生理盐水及注射前血流信号强度高２６．８±９．７ｄＢ。注射生理盐水后多普勒血流信号强度未见明显改变。结论：静脉注射２０ ％ 英脱利匹特能够增强血流信号,提高多普勒检测的敏感性。     

类风湿性关节炎患者血清IL-6、TNF水平变化及其意义探讨

采用细胞生物学方法测定类风湿性关节炎（ Ｒ Ａ）１４ 例血清 Ｉ Ｌ－ ６ 、 Ｔ Ｎ Ｆ 水平,均显著高于正常对照组（ Ｐ＜ ０ ．００１） 。相关分析显示 Ｉ Ｌ－ ６ 与 Ｔ Ｎ Ｆ 水平变化呈正相关（ Ｐ＜ ０ ．０１） , Ｉ Ｌ－ ６ 、 Ｔ Ｎ Ｆ 与血沉亦呈正相关（ Ｐ＜０ ．０５） 。认为, Ｉ Ｌ－ ６ 、 Ｔ Ｎ Ｆ 参与 Ｒ Ａ 的发病,两者在致病中有协同相同;其水平变化与 Ｒ Ａ 的活动性及血沉相关。     

Phospholipase A2 enzymes regulate alpha IIb beta3-mediated, but not Fc gammaRII receptor-mediated, pp125FAK phosphorylation in platelets

The alphaII(b)beta3 integrin and FcgammaRII receptors mediate, respectively, platelet adhesion and spreading on fibrinogen and immunoglobulin (IgG) coated surfaces. Platelet adhesion to fibrinogen resulted in a partial conversion of the faster to the slower migrating (phosphorylated) form of Ca(+2)-sensitive cytosolic phospholipase A2(cPLA2) but failed to trigger arachidonic acid (AA) release. Full mobility shift of cPLA2 and a massive release of AA release were stimulated by platelet adhesion to IgG or addition of thrombin to the fibrinogen adherent platelets. IgG and thrombin induced AA production were blocked by methyl arachidonyl fluorophosphonate (MAFP), an irreversible inhibitor of cPLA2 and the Ca(+2)-independent phospholipase A2 (iPLA2). In contrast, bromoenol lactone (BEL), a specific inhibitor of iPLA2 had no effect on the release of AA. MAFP and BEL prevented pp125FAK phosphorylation and platelet spreading on fibrinogen having no effect on pp125FAK phosphorylation or platelet spreading on immobilized IgG. We conclude that alpha(IIb)beta3-mediated pp125FAK phosphorylation and platelet spreading on fibrinogen are regulated by PLA2 enzymes.