Extensive allelic sequence variation in the J region of the human immunoglobulin heavy chain gene locus

During the initial stages of B lymphocyte differentiation heavy chain variable (VH), diversity (DH) and joining (JH) gene segments recombine to form a functional heavy chain variable region (VDJ) gene. Evidence for genetic polymorphism of the human JH gene segments has been obtained from mature rearranged VDJ sequences. We conducted an analysis of the published rearranged JH gene sequences and found that the JH alleles present in the two published germ-line JH region sequences were rare (approx. 2%) in the rearranged sequences. As an attempt to explain this discrepancy a 2.5-kb strech of DNA containing all the six heavy chain JH region genes and the most 3' DH gene segment, DHQ52, was amplified by the polymerase chain reaction from 39 individuals and analyzed for restriction fragment length polymorphism. Five new JH region haplotypes were found and sequenced. These new haplotypes contained the coding segment alleles that were frequent in antibody genes. Surprisingly, a high number of interallelic differencies in the non-coding sequence was found between the new and the two previously published haplotypes implying that the haplotypes had been separated early in evolution. In this respect the JH locus resembles HLA loci.     

频闪喉镜对声带病理情况观察的研究

对1997年以来423例病态喉的频闪喉镜表现进行分析,结果显示声带有病理改变者其粘膜波、振幅、闭合相、运动周期性、对称性均有不同程度的变化,这种变化能直接反映声带病变的深度及范围,对喉部疾病的诊断、鉴别诊断、治疗指导及预后评价具有重要意义.     

一期动静脉转流与并加压破坏深静脉瓣对比的实验研究

目的:改进一期动静脉转流术的疗效。方法:10只狗双后肢,随机选择一侧后肢行一期动静脉转流,另一侧行一期动静脉转流加水压破坏深静脉瓣。术后30天通过动脉造影进行对比研究。结果:后者能更有效地加速远段深静脉瓣的破坏,使动脉血逆行更远,同时形成更为丰富的侧枝循环,而不会增加肢体肿胀和深静脉血栓的机会。结论:一期动静脉转流加水压破坏深静脉瓣可能是治疗严重肢体缺血更为有效的方法。     

头孢托仑酯随机双盲对照治疗细菌性感染临床评价

为评价头孢托仑酯（ＭＥ１２０７）治疗细菌性感染的有效性和安全性，采用随机双盲对照试验和开放试验方法共治疗８０例患者，其中ＭＥ１２０７（Ａ药）与头孢克肟（Ｂ药）随机双盲各治疗２０例（呼吸系统和泌尿系统各１０对），ＭＥ１２０７开放试验治疗４０例（呼吸系统２０例、泌尿系统１０例、皮肤软组织感染１０例）。每日４００ｍｇ，疗程７～１４ｄ。ＭＥ１２０７痊愈率和有效率在对照试验中为８０％和９５％，在开放试验中为７５％和９２．５％，总痊愈率为７６．７％，总有效率为９３．３％，细菌培养阳性率为１００％，细菌清除率在对照试验和开放试验中分别为９５％和９２．５％。纸片法药敏试验中ＭＥ１２０７敏感株百分率为１００％，与头孢哌酮相同，而优于头孢克肟和头孢克洛，明显优于阿莫西林（４８．８％）。ＭＥ１２０７６０例中６例出现不良反应，表现为消化道反应３例，转氨酶升高２例，凝血酶原时间延长１例。与对照药头孢克肟相比在痊愈率、有效率、细菌清除率及不良反应发生方面均无显著性差异（Ｐ＞０．０５）。ＭＥ１２０７在每日４００ｍｇ剂量下治疗轻、中度细菌感染安全、有效。     

甲状腺Hürthle细胞癌(附2例报告)

甲状腺 Hürthle 细胞癌临床罕见,本文报告2例,并结合文献对其组织发生、诊断标准和治疗进行了讨论。本病在甲状腺癌中为一独立类型,镜下表现为良性者仍有潜在恶性的可能,故积极治疗才能获得良好预后。     

消炎痛对hCG诱发家兔排卵抑制的形态学研究

应用非甾体抗炎药消炎痛(20mg/kg)抑制hCG 诱发的家兔排卵,注射后的6、9、12、72小时剖腹观察排卵数,并取材进行透射电镜观察和酶组织化学观察。甾体激素合成酶类的组织化学和颗粒细胞内某些细胞器的电镜立体定量学测定结果表明:消炎痛抑制了排卵,却不影响颗粒细胞向黄体细胞的转变。透射电镜观察表明:在排卵前,实验组和对照组最明显的不同是:实验组的外膜和白膜很少见到胶原溶解现象,且表面上皮细胞内含的致密小体不释放其内容物。结果提示:消炎痛主要作用于排卵前卵泡顶部的成纤维细胞和表面上皮细胞,这可能与其抑制了某些与排卵有关的酶的释放有关。     

Familial dyslipidemic hypertension. Evidence from 58 Utah families for a syndrome present in approximately 12% of patients with essential hypertension

Population-based sibships with essential hypertension diagnosed before the age of 60 years are being screened in Utah to find two or more hypertensive siblings with the same biochemical abnormality as a clue to an inherited cause for their specific type of hypertension. Among 131 hypertensive subjects in 58 sibships, concordant abnormalities in fasting serum lipid concentrations were observed in two or more siblings in 48% of the sibships. After adjusting for effects of antihypertensive medications, abnormal values reported in only 10% of the Lipid Research Clinics data were observed in 30% of patients for serum triglycerides, 19% for serum low-density lipoprotein cholesterol, and 39% for high-density lipoprotein cholesterol. More than one lipid level was abnormal in almost all concordant sibships, suggesting an association between hypertension and a syndrome of mixed lipid abnormalities, probably familial combined hyperlipidemia (renamed "familial combined dyslipidemia" because of common low high-density lipoprotein cholesterol levels). We conclude that familial dyslipidemic hypertension may be a specific syndrome with lipid abnormalities more severe than blood pressure elevations.     

Delayed Tc-99m-PMT imaging in the specific diagnosis of hepatocellular carcinoma

The results of Tc-99m-PMT imaging on 100 patients with various malignant and benign hepatic diseases verified histologically (73 hepatocellular carcinoma, 3 liver cell adenoma, 1 cholangiocarcinoma, 5 metastatic liver carcinoma, 2 liver cyst, 12 hemangioma, 1 fatty degeneration, 1 liver regeneration, 1 postoperative liver fibrosis and 1 liver cirrhosis) are reported. All lesions appeared as decreased radioactivity or "cold" defect region on early Tc-99m-PMT imaging, rendering it valuable for the diagnosis of tumor localization. In 92 (95.8%) of the 96 patients with various hepatic tumors and 25 (86.2%) of the 29 patients with small hepatocellular carcinoma (less than 5 cm), the tumors were localized by early Tc-99m-PMT imaging. In 14 of the 73 patients with established hepatocellular carcinoma, the tumors gave greater radioactivity than that of the surrounding liver tissues, whereas in 31 patients the radioactivity of the tumor equalled the normal liver on delayed Tc-99m-PMT imaging (positive rate 61.6%). There was no significant difference between the positive rates of serum AFP level and the tumor size shown by delayed Tc-99m-PMT imaging in hepatocellular carcinomas. The radioactivity in 3 liver cell adenoma patients was similar to the gallbladder. No false positive result was seen in the other malignant and benign hepatic tumors. This study indicates that delayed Tc-99m-PMT imaging is highly specific in the diagnosis of hepatocellular carcinoma.     

MITOCHONDRIAL MYOPATHY AND MITOCHONDRIAL ENCEPHALOMYOPATHY

This paper is the first report of mitochondrial encephalomyopathy and mitochondrial myopathy diagnosed in China. It includes l case of mitochondrial encephalomyopathy with lactic acidemia and stroke-Iike episodes (MELAS), 5 cases of mitochondrial myopathy with skeletal muscles predominantly involved, and 2 cases of mitochondrial myopathy with external ocular muscles predominantly involved. The diagnosis was confirmed by muscle biopsies which revealed the "ragged-red-fiber" CRRF) in modified Gomori trichrome CMGT) stain, accumulation of lipie droplets in oil-red-O stain in frozen sections, and aggregates of abnormal mitochondria with complex paracrystalline inclusions and distorted cristae and osmiophilic dense bodies in their matrix in electron microscopy.     

Neural interactions mediating the detection of motion in the retina of the tiger salamander

The neural circuitry underlying movement detection was inferred from studies of amacrine cells under whole-cell patch clamp in retinal slices. Cells were identified by Lucifer yellow staining. Synaptic inputs were driven by "puffing" transmitter substances at the dendrites of presynaptic cells. Spatial sensitivity profiles for amacrine cells were measured by puffing transmitter substances along the lateral spread of their processes. Synaptic pathways were separated and identified with appropriate pre- and postsynaptic pharmacological blocking agents. Two distinct amacrine cell types were found: one with narrow spread of processes that received sustained excitatory synaptic current, the other with very wide spread of processes that received transient excitatory synaptic currents. The transient currents found only in the wide-field amacrine cell were formed presynaptically at GABAB receptors. They could be blocked with baclofen, a GABAB agonist, and their time course was extended by AVA, a GABAB antagonist. Baclofen and AVA had no direct affect upon the wide-field amacrine cell, but picrotoxin blocked a separate, direct GABA input to this cell. The narrow-field amacrine cell was shown to be GABAergic by counterstaining with anti-GABA antiserum after it was filled with Lucifer yellow. Its narrow, spatial profile and sustained synaptic input are properties that closely match those of the GABAergic antagonistic signal that forms transient activity (described above), suggesting that the narrow-field amacrine cell itself is the source of the GABAergic interaction mediating transient activity in the inner plexiform layer (IPL). Other work has shown a GABAB sensitivity at some bipolar terminals, suggesting a population of bipolars as the probable site of interaction mediating transient action. The results suggest that two local populations of amacrine cell types (sustained and transient) interact with the two populations of bipolar cell types (transient forming and nontransient forming). These interactions underlie the formation of the change-detecting subunits. We suggest that local populations of these subunits converge to form the receptive fields of movement-detecting ganglion cells.