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Biomedical subjects

D Fang

Publications and source records attributed to D Fang.

At least 91 records · Page 5Linked to original sources

Impacts of atmospherically deposited radionuclides on drinking water supply after a nuclear power plant accident.

This paper analyzes the various possible situations in which a drinking water supply in China may be contaminated by the deposition of airborne radioactive effluent after reactor accidents occur. A model was utilized to calculate the impact of ingestion of contaminated drinking water from a reservoir after a design basic accident of a 900-MWe pressurized water reactor power station. It showed that the maximum individual effective dose caused by a contaminated drinking water supply was at most 0.02% of the total individual effective dose from a reactor design basic accident. This factor was not considered when evaluating the consequence of a reactor design basic accident since, under several unfavorable conditions, the contamination of a drinking water supply from airborne radioactive effluent after a reactor design basic accident is not a major contributor to the impact on individual effective dose. It may be necessary to consider surface water contamination by deposition of airborne radioactive effluent for an emergency plan after a serious accident.

Accidents↗

[Study of clearance and distribution of 125I-labeled apolipoprotein CIII in mice].

Using 125I-labeled human apoCIII, the clearance and distribution of 125I-apoCIII were investigated. Human apoCIII was purified from plasma VLDL. 125I-apoCIII was prepared by chloramine T method, The fraction clearance rate (FCR) value of 125I-apoCIII in mice plasma was 0.19/h with a plasma half life of 3 h. The radioactivity in different organs after the venous injection of 125I-apoCIII exhibited that the liver contained radioactivity 3-10 times as much as the reactivity in other organs, expressed by both the whole organ and 100 mg of tissues. Results show that there might occur some specific binding sites for apoCIII on liver cells.

Animals↗

Dependence of reaction rate of 5,5'-dithiobis-(2-nitrobenzoic acid) to free sulfhydryl groups of bovine serum albumin and ovalbumin on the protein conformations.

The effect of protein conformations on the reaction rate of Ellman's reagent, 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) with sulfhydryl (SH) groups of proteins was examined. The stopped-flow method was applied to follow the reaction of DTNB with SH group of two proteins, bovine serum albumin (BSA) and ovalbumin (OVA), at various concentrations of guanidine hydrochloride and urea. The rates for both the proteins were faster in guanidine than in urea. The rate sharply depended on the protein conformations, which were monitored by changes of helix contents on the basis of the circular dichroism measurements. The reaction rate of DTNB with SH groups of BSA was maximal around 2 M guanidine and 5 M urea. On the other hand, the reaction rate of DTNB with OVA was maximal at 3.5 M guanidine, while it gradually increased with an increase in the urea concentration. The amount of reactive SH group participating in the reaction with DTNB was also estimated by the absorbance change at 412 nm. The magnitudes of absorbance change for the reaction with free SH groups of OVA at low concentrations of the denaturants were appreciably smaller than those for BSA with one free SH group. Most of the four SH groups of OVA might react with DTNB above 5 M guanidine, although only a part of them did even at 9 M urea.

Dithionitrobenzoic Acid↗

A study of function and residual joint stiffness after functional bracing of tibial shaft fractures.

Ninety-eight diaphyseal tibial fractures were treated with custom made functional braces in 97 patients older than 14 years of age. The average follow-up period was 1.86 years, and 53 patients had more than two years' evaluation (average, 2.83 years). The majority of the patients did not have full range of movement in the ankle and subtalar joints when the brace was removed after fracture healing. Although the stiffness decreased with time, a significant number of patients were left with residual joint stiffness. At an average follow-up period of 1.86 years, 68.4% of the patients had normal ankle motion and 60% had normal inversion and eversion of the hindfoot. In patients with more than two years' evaluation, 75.5% had normal ankle movement and 71.1% had normal inversion and eversion of the foot. In the knee joint, the incidence of residual joint stiffness was small and the amount of stiffness was clinically insignificant. Patients with an abnormal walking pattern after fracture healing had a high incidence of ankle and subtalar joint stiffness.

Adolescent↗

[A study on the tumorigenic process of mesothelioma induced by intrapleural injection of crocidolite in rats].

90 Wistar strain rats were used in this experiment, 56 rats (Group A) were injected intrapleurally with crocidolite fibers suspended in physiological (NaCl) solution. Another 34 rats (Group B), serving as controls, were injected with the same volume of mere NaCl solution. The rats were killed 1, 3, 6, 9, 12, 14 and 16 months respectively after injection. The results showed that the rats of Group B only exhibited reactive proliferation of mesothelial cells caused by inflammation. In Group A, there appeared 9 cases of mesothelioma. The tumorigenic stages of mesothelioma include three processes: (1). reactive proliferation: the mesothelial cells became cuboid. (2). precancerous changes: the atypical proliferation of stratified, nodular or papillary mesothelial cells and of the cell elements around asbestos granulomas. (3). the occurrence of mesothelioma. Ultrastructural observation revealed that in mesothelioma tissue mesenchymal cells directly or indirectly (via transitional cells) differentiated cinto epithelioid cells. The mesenchymal cells may also become fibroblastoid cells. These findings suggest that mesothelioma originates from mesenchymal cells.

Animals↗

Post-traumatic oedema of the foot after tibial fracture.

A total of 97 patients with diaphyseal tibial fractures treated with functional bracing were studied prospectively. Persistent ipsilateral foot swelling was present in 84.5 per cent of the patients. Most of the swellings subsided with time, but a small percentage of them persisted for a duration of 2 years or more after injury. The time for disappearance of the swelling in 50 per cent of the patients was 18.6 weeks. The development of oedema is not related to the age and sex of the patients, the configuration, type and level of the fractures, or the association of a fibular fracture. The bone healed quicker in those who did not have swelling of the foot. Once the swelling has developed, it seems to run its own course and its disappearance is not related to the age and sex, the configuration, type and level of fractures, the association of a fibular fracture, or the time for fracture healing. This complication does not have any adverse effect on the functional recovery of the patients.

Adolescent↗

Anterior spinal fusion for spondylolysis and isthmic spondylolisthesis. Long term results in adults.

We reviewed 20 adult patients with spondylolysis and isthmic spondylolisthesis an average of 10.5 years after treatment by anterior spinal fusion. Nineteen patients had excellent or satisfactory results. Ten of the patients were symptom-free at one year, and 15 were asymptomatic at final follow-up. Anterior spinal fusion can produce results comparable to those of posterior fusion with or without decompression. The results tend to improve with time in contrast to the known worsening of late results after posterior decompression without fusion.

Adolescent↗

[Morphologic studies on the adulterant sharen in Alpinia].

In this paper, morphological studies on adulterant Sharen including eighteen fruits in Alpinia are reported. The morphological differences between genuine Sharen and its adulterants are distinct on their fruits, seeds and embryos. In addition, the distinguished characters for identification of the eighteen fruits and seeds are described with drawings and compared in a table.

Drug Contamination↗

[Studies on the histology and essential oils of the adulterant sharen in Alpinia].

Morphological studies on eighteen adulterants of Sharen in Alpinia had been carried out previously. In this paper, a report on the histology and essential oil of their seeds is presented. According to our TLC analysis and microscopical examination, the differences between genuine Sharen and its adulterants are distinct in histological characters and constituents of the essential oil. A description of identification of these eighteen seeds is given together with line drawings, chromatograms and a table for comparison.

Chromatography, Thin Layer↗

Cervical myelopathy due to ossification of the posterior longitudinal ligament. A clinical, radiological and evoked potentials study in six Chinese patients.

Six consecutive Chinese patients with cervical myelopathy due to ossification of the posterior longitudinal ligament (OPLL) who presented in a 4 yr period were studied. There were 5 males and 1 female whose mean age at presentation was 67 yrs. The common clinical features were spastic tetraparesis more marked in the lower limbs, spinothalamic and posterior column sensory deficits of varying degree and sphincter disturbance in advanced cases. OPLL was diagnosed on plain radiographs and cord compression ascertained by conventional and computer-assisted myelography. Somatosensory evoked potentials correlated with posterior column signs and appeared to reflect the clinical course following treatment. While the cord pathology in OPLL is similar to that of cervical spondylotic myelopathy (CSM), the pathogenetic mechanism probably differs in one aspect. Compression by OPLL is the determining factor in most cases whereas the combined presence of a congenitally narrow canal and spondylosis is essential for the development of CSM. Other contributory factors include coexisting spondylosis, a congenitally narrow canal, friction between cord and OPLL during neck movement and acute trauma. Cord damage is probably mediated by ischaemia which is due to disturbances of the microcirculation caused by the mechanical factors.

Aged↗

Spinal pseudarthrosis in ankylosing spondylitis. Clinicopathological correlation and the results of anterior spinal fusion.

We reviewed 40 extensive destructive vertebral lesions in 35 patients with established ankylosing spondylitis. Of these, 31 had presented with localised pain while three had a neurological deficit. The radiographs suggested ununited fractures through either ankylosed discs (37) or vertebral bodies (3). Corresponding fractures were seen in the posterior column in 34 cases. Sixteen patients with 18 lesions underwent anterior spinal fusion, and pseudarthrosis was consistently proven by histopathology. Two pseudarthroses healed in conservatively treated patients. Thirteen of the operated patients were followed for an average of 7 years 7 months. There were two cases of non-union and one required an additional posterior fusion; in the remainder fusion was sound.

Adult↗

The pathogenesis of extensive discovertebral destruction in ankylosing spondylitis.

The study of extensive discovertebral destructive lesions in ankylosing spondylitis has been largely limited to isolated case reports or clinicoroentgenologic reviews with little pathologic correlation. In eight specimens of the spine collected from 35 patients with ankylosing spondylitis showing extensive discovetebral destructive lesions, a detailed pathologic study revealed a consistent picture of complete or near-complete destruction of the disc-bone border and the intervertebral disc. The disc was replaced by fibrous tissue and/or fibrocartilage showing moderate to severe fibrinoid necrosis and cystic degeneration. Such changes are characteristic of pseudarthrosis, which may follow either fracture or degeneration of the disc perpetuated by abnormal stress and motion. The reparative process included fibrovascular tissue proliferation from the vertebral bone marrow. Fibrovascular tissue also perforated the vertebral end-plate and intervertebral spaces resulting in massive discovertebral destruction. Pathologic observations strongly implicate mechanical trauma and pseudarthrosis as initiating and perpetuating extensive discovertebral destruction in ankylosing spondylitis.

Adult↗