管状骨增宽牵引成骨组织形态学变化的实验研究

目的 探讨管状骨增宽牵引后新骨形成的变化。方法 在成年山羊的后肢放置2只增宽牵引器。实验组9只术后第8天牵引，对照组3只不牵引。牵引完毕后不同时期，各宰杀3只，评价管状骨增宽牵引后新骨形成的质和量。结果 实验组胫骨平均增宽7．83mm，X射线见牵引间隙逐渐变模糊，暴露侧有骨不连，非暴露侧成骨良好，牵引完毕3个月，未暴露侧新形成板层骨与原来胫骨融为一体，而暴露侧骨不连区为致密纤维组织。结论 管状骨增宽牵引成骨后，两侧牵引间隙成骨不一致，良好的血供，对新骨形成至关重要。     

Link protein shows species variation in its susceptibility to proteolysis.

Human cartilage link protein exists as three native components, while equine, bovine, and porcine cartilage link protein exist as two and Swarm rat chondrosarcoma link protein exists as only one component. These nonhuman link protein components represent intact protein structures, and there is little evidence for proteolytically modified forms in nonhuman tissues. In human cartilage, the proteolytic production of modified link proteins increases with age, whereas high amounts of such products were not seen in the nonhuman tissues. However, the small amounts of link protein fragments that were observed in the nonhuman cartilages were of a similar size to their human counterparts. On digestion of human proteoglycan aggregate with stromelysin, rapid modification of the link protein components occurred, whereas the aggregates from nonhuman cartilages showed incomplete cleavage of their link protein components. The relative resistance of nonhuman link protein to stromelysin may in part be due to a unique amino acid substitution present near the enzymic cleave site.     

Scale-up of Adhesive Transdermal Drug Delivery Systems

Pharmaceutical Research -     

In vitro effect of zinc on oxidative changes in human semen

Summary The in vitro effect of zinc on superoxide anion (O₂^?) generation and on experimentally induced lipid peroxidation (LPO) in spermatozoa of infertile men was investigated. Washed spermatozoa pre-incubated for 30 min at 37°C in the presence of 1 or 3 mmol l^-1 zinc, released less superoxide anions (P<0.03 and P<0.02, respectively; n=9) than the untreated spermatozoa. Similar results were obtained using activated polymorphonuclear leukocytes (1 times 10⁶ cells ml^-1) in the presence of 1 or 3 mmol l^-1 Zn (P<0.001 and P<0.0002, respectively; n=9). The in vitro evidence of the inhibitory effect of zinc on O₂^? generation by human spermatozoa and leukocytes indicates that zinc may act in vivo as a scavenger of excessive O₂^? production by defective spermatozoa and/or leukocytes in semen after ejaculation. A significant stimulatory effect of Zn (3 mmol l^-1) on iron-induced lipid peroxidation, measured by the formation of thiobarbituric acid reactive substances (TBARS), was detected in the spermatozoa of 16 normo- and 17 asthenozoospermic males (P<0.0001 and P<0.001, respectively). In 11 samples with sperm concentration 20.3±2.1 times 10⁶ ml^-1, exhibiting initial TBARS concentration two times higher than in normo-and asthenozoospermic samples (40.5±2.4 vs. 17.1±1.1 and 28.5±4.1 nmoles TBARS 10^-8 spermatozoa), no effect of zinc on the LPO rate was found. The observed inhibitory effect of zinc on superoxide anion regardless of the initial O₂^? level and stimulatory effect of zinc depending on the initial LPO rate in human spermatozoa suggests that this metal ion participates in the oxidative changes occurring after ejaculation and thus may modulate the properties of germ cells.     

Disorders of perfusion of the anterior segment of the eye

Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process.     

The effects of intermittent administration of human parathyroid hormone (1–34) on streptozotocin-induced diabetic rats

Intermittent administration of low doses of human parathyroid hormone (h-PTH) has been reported to exhibit an anabolic effect on bone, increasing its mass. We investigated the effects of intermittent administration of h-PTH on bone changes in streptozotocin- (STZ-) induced diabetes mellitus (DM) rats by measuring bone mineral density and bone mineral contents and by bone histomorphometry. Wistar rats, 7–8 months old, were used. Osteoporosis was induced by diabetes mellitus, which was established by an intraperitoneal injection of STZ. Rats were separated into five groups: sham-injected, baseline control, vehicle-only-administered, and low-dose (6.0μg/kg) or high-dose (60.0μg/kg) h-PTH-administered groups. h-PTH or vehicle was injected subcutaneously six times a week for 4 weeks beginning 9 weeks after STZ administration. Bone mineral density and mineral contents were significantly lower in the baseline control and vehicle groups than in the control group. The PTH-administered groups showed higher values compared with both vehicle and baseline control groups. In bone histomorphometry, both bone volume and bone formation in the STZ group were markedly reduced. The h-PTH-administered rats showed increase in both bone volume and bone formation, which are related parameters, but administration of h-PTH did not alter the extent of eroded surface. Our results suggest that intermittent administration of h-PTH is effective in activating bone formation and in preventing further bone loss in osteoporosis developed by STZ-induced DM.     

颅内疾病的心电图改变

目的 :探讨颅内疾病的心电图改变及对预后的影响。 方法 :将我院 1999年以来的 10 2例颅内疾病患者的心电图资料按病因分为 4组 ,所有患者均于发病 1～ 2d内入院 ,常规描记 12导联心电图 ,住院期间定期复查。结果 :心电图改变主要为复极障碍 (ST段下移 ,T波倒置、低平或双向以及Q T间期延长 ) ,其次为心律失常。 4 0例重型颅脑外伤及蛛网膜下腔出血者中心电图异常 36例 ,正常 4例 ,死亡组心电图异常率及程度均重于存活组。结论 :“脑型心电图改变”主要表现为ST T改变和冲动起源异常的心律失常是暂时的应激反应。发生急性颅内病变时要及时识别 ,积极予以处理 ,以减轻脑损伤所致的心脏损害。     

Age-related changes in cortical porosity of the midshaft of the human femur

Complete cross-sections from the femoral midshaft of 180 individuals of known height and weight, aged 21–97 y, from a modern Australian population were examined using automatic video image analysis to quantify total subperiosteal porosity (TSPP). More specifically, the aim was to investigate whether age changes were similar in both sexes in (1) total subperiosteal area (TSPA), cortical area (CA) and medullary area (MA), (2) intracortical porosity (ICP), and (3) the respective contributions to TSPP made by MA and intracortical void area (ICVA). Our findings indicated that both sexes showed a significantly greater height normalised TSPA in the 70s as compared with the 20s. Males had consistently larger bones with a greater height normalised CA. In both sexes CA showed a tendency to increase till the 7th decade and then to decline, more so in females. MA approximately trebled in females and doubled in males over the age range studied. Although ICP also increased, from 4–6% in young adults to over 9% in the elderly, it showed a significant difference between the sexes only in the 3rd decade, being greater in males at this stage. By contrast, TSPP became significantly greater in females (from that recorded in the 3rd decade) by the time they reached the 50s, while in males this did not occur till the 80s. It increased from ∼25% in young adults of both sexes to ∼50% in females and ∼37% in males in their 80s. However, in the elderly there was great variability in both sexes in the appearance of bones from individuals of similar chronological age. Some bones differed little from those in younger subjects, others showed greatly increased ICP, still others displayed reduced cortical widths with low ICP. The femoral midshaft resembles other skeletal sites in that age changes in TSPP are more marked in females than males.