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Biomedical subjects

S X Zhu

Publications and source records attributed to S X Zhu.

At least 19 recordsLinked to original sources

[The behaviour of rabbit ICM in culture system in vitro].

The behaviour of ICMs isolated from early blastocysts of rabbit by microsurgery and incubated in cultural system in vitro, are varied according to the growing state of ICM. The band type growing extends from the proximal to the distal end, while the differentiation of cells in this kind initiates from the distal toward the proximal and gradually. The band type ICM possesses obvious polarity. The differentiation of different kind of cells appear one after another in order and the arrangement of differentiated germinal layer are clearcut. Therefore, the band type ICM is a good model for the investigation of differentiation cell and cell lineage. Whereas the ball type of growing ICM possesses no polarity. The cell in this type of ICM appears to differentiate from the outer surface of the ball toward the center gradually. The cellular differentiation starts later and the rate of proliferation of differentiated cells are lower than those of the band type ICM. After 7 days of incubation in vitro most of the ICM remain undifferentiation. The ball type ICM is a good model for the isolation of the embryonic stem cell line. There are two steps that the extraembryonic endoderm of rabbit are differentiated from ICM. The first kind of extraembryonic endoderm formed from ICM after 3 days of incubation in vitro. It is the parietal extraembryonic endoderm which migrate so far from the primitive ectoderm. The second kind of extraembryonic endoderm differentiates from ICM after 4 days of incubation in vitro. It is the visceral endoderm, most of which followed the migration of the first endoderm and the rest of them invade into the trophectoderm near the primitive ectoderm.

Animals

Iliac periosteal graft with vascular pedicle in the treatment of avascular necrosis of the femoral head. Experimental study and clinical application.

From March 1983 to June 1987, 6 patients with avascular necrosis of the femoral head were treated with vascular pedicled iliac periosteum graft. Follow-up for 3 to 7.5 years showed satisfactory results. The patients experienced no hip pain, could walk freely, and resumed work after the treatment. X-ray films showed that the original defect of the femoral head was filled up and its outline was clear and smooth. The bone density of the femoral head and neck normalized. The experimental study indicated that the vascularized periosteum improves the blood supply and initiates the revascularization and osteogenesis of the femoral head. The authors conclude that the technique is suitable for the treatment of avascular necrosis of the femoral head of Stage II and III.

Adolescent

Aortic compliance in human hypertension.

Aortic compliance in normotensive and hypertensive Chinese subjects undergoing diagnostic cardiac catheterization was compared by using a newly described method that allows for determination of the pressure dependence of compliance if one assumes a value for the exponential coefficient of the pressure-volume relation of the large arteries. Under baseline conditions in the normotensive and hypertensive groups at mean aortic pressures of 96.3 and 128.6 mm Hg, aortic compliance averaged 1.47 and 0.80 ml/mm Hg, respectively. Compliance in the hypertensive group at a diastolic pressure of 99.4 mm Hg (which was nearly equal to the mean normotensive pressure) was 1.072 ml/mm Hg--still significantly lower than in the normotensive group. During nitroprusside infusion, however, the compliances in the hypertensive group increased to levels equal to or greater those in the normotensive group. Thus, these data confirm that aortic compliance is lower in hypertensive than in normotensive humans. They further demonstrate that the lower compliance cannot be attributed entirely to the elevated blood pressure, suggesting that excess smooth muscle tone may be partly responsible.

Adult

Transposition of iliac periosteum with vascular pedicle and compression screw fixation for transcervical fracture of femur. Experimental research and clinical application.

The vascular pedicled periosteum was used in 11 cases in our hospital for the treatment of femoral neck fracture with good result. The follow-up period ranged from 2 to 6 years, with an average of 4 years. Animal experiment was made to elucidate the repairing process. It demonstrated that the pedicled periosteum played double roles, namely, blood supply and osteogenesis. The clinical and experimental results are presented.

Adolescent

[Treatment of traumatic shortening of the legs in adults].

Non-traumatic shortening of lower extremities can be lengthened by osteotomy, traction or bone grafting. In traumatic shortening, treatment is limited by several reasons and emphasis should be put on bone healing and preserving of loading and walking functions. The lengthening of lower extremities has some difficulties. Recently, we have adopted a method in which we transposed muscle-skin flap to repair the stick-bone scar in the early stage, and performed traction with Hoffman extra-frame (when osteotomy is needed) in the mid-stage and bone grafting (with or without vascularity) in the late stage. From April 1984 to April 1986, seven patients were treated by this method. The result was satisfactory. In this article is discussed the pathologic characteristics of traumatic shortening of the lower extremities and the role of the gastrocnemius in repairing skin defect.

Adult

Experimental study of bridging the peripheral nerve gap with skeletal muscle.

A piece of skeletal muscle was used as a conduit to bridge the gap microsurgically between the two ends of the severed sciatic nerve in 30 rats, and a method for histochemical demonstration of acetylcholinesterase was employed to assess the nerve regeneration process 5 weeks or more after the operation. Regenerating nerve fibers were detected in the muscle and could be traced through to the distal stump of the severed sciatic nerve. This suggests that skeletal muscle might serve as a grafting conduit for the repairing of peripheral nerve injuries.

Animals

Intrafascicular decompression in the treatment of causalgia with special reference to the mechanism.

A new concept of the pathogenesis of causalgia is suggested in accordance with experimental and clinical work. Endoneural hypertension secondary to nerve trunk disruption is incriminated and intrafascicular decompression is used as the key therapeutic measure. In 14 patients with causalgia thus treated, all except 1 were cured. No symptomatic recurrence was noted in a 4- to 6-year follow-up study.

Adolescent

Free musculocutaneous flap transfer of extensor digitorum brevis muscle by microvascular anastomosis for restoration of function of thenar and adductor pollicis muscles.

This article reports 3 cases of surgical restoration of function of the thenar muscle and the adductor pollicis muscle of the thumb with free musculocutaneous flaps of the extensor digitorum brevis muscle of the toe by microsurgical technique. Two years' follow-up revealed good functional recovery of the hand with normal electromyographic findings and grade 3-4 muscular power.

Adolescent