喉癌患者染色体对致突变剂诱发畸变的敏感性研究

采用平阳霉素作为诱变剂，对２８例喉癌患者和２３例正常人做外周血淋巴细胞染色体对诱变剂敏感性研究，结果显示喉癌患者的染色体总畸变率、每细胞染色单体断裂率（ｂ／ｃ值）和细胞畸变率分别为１．９８％±０．０５％，０．５７％±０．３５％和４２．８％±１２％。正常人则分别为０．９４％±０．０４％，０．２８％±０．１２％和２７％±１２％。经统计学处理，喉癌患者组与正常人组的差异有高度显著性。并结合实验结果探讨了染色体对致突变剂的敏感性与患喉癌风险的关系。     

Electrocardiographic findings in children with Lyme disease.

The incidence of cardiac involvement in Lyme disease (LD) has been estimated to be 4 to 10% in adults, with conduction and rhythm disturbances noted most frequently. To assess the frequency of electrocardiographic abnormalities in children with LD, we prospectively performed 12-lead electrocardiograms in 32 randomly selected children presenting with LD between May and September 1989. No patient had symptoms of cardiac involvement. Using defined diagnostic criteria, combining symptoms, signs, serology, and residence in or travel to an endemic area, 14 patients were classified as having definite LD and 10 were categorized as probable. The incidence of electrocardiographic abnormalities in the definite group was 29% (4/14), including two patients with 1 degree atrioventricular block, one with left axis deviation, and one with ventricular ectopy. Thirty percent (3/10) of the probable group had abnormal ECGs, including one with ST-T wave abnormalities, one with prominent sinus arrhythmia, sinus bradycardia, and wandering atrial pacemaker, and one with ectopic atrial bradycardia. No patient required cardiac therapy. The incidence of abnormal ECG findings in this group of children with either probable or definite LD was thus 29%, with 1 degree atrioventricular block noted most frequently. When the diagnosis of LD is highly suspected, an electrocardiogram may be a useful screening test for cardiac involvement.     

In situ forces in the anterior cruciate ligament and its bundles in response to anterior tibial loads

The anterior cruciate ligament has a complex fiber anatomy and is not considered to be a uniform structure. Current anterior cruciate ligament reconstructions succeed in stabilizing the knee, but they neither fully restore normal knee kinematics nor reproduce normal ligament, function. To improve the outcome of the reconstruction, it may be necessary to reproduce the complex function of the intact anterior cruciate ligament in the replacement graft. We examined the in situ forces in nine human anterior cruciate ligaments as well as the force distribution between the anteromedial and posterolateral bundles of the ligament in response to applied anterioi tibial loads ranging from 22 to 110 N at knee flexion angles of 0–90°. The analysis was performed using a robotic manipulator in conjunction with a universal force-moment sensor. The in situ forces were determined with no device attached to the ligament, while the knee was permitted to move freely in response to the applied loads. We found that the in situ forces in the anterior cruciate ligament ranged from 12.8 ± 7.3 N under 22 N of anterior tibial load applied at 90° of knee flexion to 110.6 ± 14.8 N under 110 N of applied load at 15° of flexion. The magnitude of the in situ force in the posterolateral bundle was larger than that in the anteromedial bundle at knee flexion angles between 0 and 45°, reaching a maximum of 75.2 ± 18.3 N at 15° of knee flexion under an anterior tibial load of 110 N. The magnitude of the in situ force in the posterolateral bundle was significantly affected by knee flexion angle and anterior tibial load in a fashion remarkably similar to that seen in the anterior cruciate ligament. The magnitude of the in situ force in the anteromedial bundle, in contrast, remained relatively constant, not changing with flexion angle. Significant differences in the direction of the in situ force between the anteromedial bundle and the posterolateral bundle were found only at flexion angles of 0 and 60° and only under applied anterior tibial loads greater than 66 N. We have demonstrated the nonuniformity of the anterior cruciate ligament under unconstrained anterior tibial loads. Our data further suggest that in order for the anterior cruciate ligament replacement graft to reproduce the in situ forces of the normal anterior cruciate ligament, reconstruction techniques should take into account the role of the posterolateral bundle in addition to that of the anteromedial bundle.     

脊髓萎缩（附2例报告）

本文报告了两例脊髓萎缩，并结合文献复习讨论了该病的好发部位、病因、临床表现、诊断和治疗。脊髓萎缩的病因多为继发性，也可为特发性。根据临床表现结合脊髓ＣＴ造影及ＭＲＩ检查，可以明确诊断。     

肢体不同延长速度对局部血流量的影响

本文报告20只兔胫骨以不同速度延长时用末梢微循环测定系统动态连续监测局部血流量变化的结果,发现一次延长>1 mm时,局部肌肉血流量开始急骤下降,恢复延长前血流量所需的时间>8 h。作者认为肢体的血管、肌肉等组织对1 mm/次/d延长速度有相当大的生物适应性。延长速度>1 mm/次/d易造成局部血流量大幅度减少。延长肢肌肉萎缩、肌力减弱可能与血流量减少有关。     

Apparently silent somatotroph adenomas.

We describe here 9 patients with somatotroph adenomas associated with mild features of acromegaly and basal plasma GH levels in the normal range. In 5 women and 4 men, 26 to 61 yrs old, the diagnosis of prolactinoma or non-secreting pituitary adenoma had been previously made on the basis of amenorrhea-galactorrhea or tumoral symptoms. However, they had discrete signs of coarsening of the facial features and moderate but evolutive changes of hand and foot sizes. Basal GH levels were in the normal range (0.4 to 4.5 micrograms/l, N less than 5 micrograms/l) but unaffected by oral glucose and insulin tolerance tests while IGF-I concentrations were elevated in all the cases (range 1.7 to 5.8 U/ml, N: 0.37-1.41 U/ml). Plasma PRL concentrations were elevated in 5 patients (range 16 to 80 micrograms/l, N less than 13 micrograms/l in men and N less than 19 micrograms/l in women). The 9 patients had a macroadenoma with an extrasellar extension in 8 of them and all were operated on by the transsphenoidal route. Immunocytochemical studies demonstrated IRGH-cells in all the adenomas and IRPRL-cells in 5 of them. Electron microscopic analysis of 3 tumors showed that the secretory granules were sparse and the Golgi apparatus poorly developed. Molecular biology of 7 tumors showed the presence of small amounts of GH mRNA. This result was in agreement with the morphological aspect, suggesting a low rate of GH synthesis. Thanks to these different approaches the diagnosis of silent somatotroph adenoma should sometimes be reconsidered.(ABSTRACT TRUNCATED AT 250 WORDS)