Objective　To Investigate the pathogenesis of chronic idiopathic urticaria.Methods　Basophil histamine release assay was utilized.Result　15 of 32 cases(46.9%)had increased serum histamine releasing activities. This implied that anti-FcεR1 and anti-IgE autoantibodies existed in the sera of some patients with chronic idiopathic urticaria.Conclusion　It suggested that autoimmunity might take part in the occurrence of some patients with chronic idiopathic urticaria.

Objective To investigate the influences of photochemotherapy with psoralen and ultraviolet A (PUVA) on skin photoaging and its possible mechanism. Methods HE stain, Verhoeff stain, electron microscopy, enzyme cytochemistry and immunocytochemistry were used to study influences of PUVA on the skin photoaging with characteristic biological markers in the non-lesion back skin of patients with psoriasis vulgaris. Results After treatment with PUVA, the degenerated collagen and elastic fibers were increased with derangement profile in dermis, and fibroblasts displayed growth suppression and morphological changes of cell senescence with a permanent switch of mitotic to stably postmitotic phenotypes, of group B and group A, the positive rates of SA-?-Gal were 13.6 % and 0.00 % and the positive rates of p16 protein were 81.8 % and 42.9 % respectively, there were significant differences between group B and group A(? 2=21.412, P

Objective To investigate the cause of excessive collagen accumulation in keloid tissue. Methods The ultrastructure of keloid was observed by transmission electron microscope. New formed collagen in keloid was localized with ABC immunohistochemical staining. Type I procollagen mRNA level in keloid tissue was determined by dot blot hybridization using human pro-al (I)collagenspecific cDNA probe. Results Numerous fibroblasts with abundant, well developed rough endoplasmic reticulum were exhibited in the ultrastructure of keloid. The type I procollagen mRNA levels were significantly increased in kreloid tissue. Immunohistochemical staining showed increased expression of new formed, type I procollagen in keloid tissue. Conclusion the fibroblasts are activated in collagen synthesis in active keloid. The enhanced collagen synthesis by fibroblasts is a critical factor leading to the overabundant collagen accumulation in keloid.

Objective To investigate the interaction between dermal papilla cells and hair follicle epithelial cells,to understand the regulation of hair follicle growth cycle, and to find out the pathway of hair follicle reconsitution in vitro and in vivo. Method Human dermal papilla cells and hair follicle epithelial cells were cultured in the same or separated compartments.The cells were counted in different phases and the cell growth pattern was observed. Results The two kinds of cells could stimulate the proliferation each other.Human hair follicle epithelial cells could induce dermal papilla cells to aggregate and form dermal papilla－ like structure. Conclusion There is a mutual interaction between the epithelial cells and dermal cells of the hair follicle.The growth and development of hair follicle is regulated by the interaction of these cells.

Objective To investigate effect on telomerase activity of Hep-2 cells treated by anticancer drugs(hydroxycamptothecine, cisplatin and cytoxan).Methods By MTT method,we measured the 50% inhibitory concentration(IC 50 ) at 72h,and compared to untreated control cells. Telomerase activity of Hep-2 cells treated by the drugs in different concentration based on IC 50 for different time was observed by Telomeric Repeat Amplification Protocol with ELISA(TRAP-ELISA).Results Hydroxycamptothecine and cytoxan could inhibit proliferation of Hep-2 and down-regulate telomerase activity of Hep-2 cell. However, cisplatin promoted proliferation of Hep-2 and up-regulated telomerase activity of Hep-2 cell.Conclusions Hydroxycamptothecine and cytoxan could down-regulate telomerase activity of Hep-2 cell by direct or indirect pattern, which may correlate with drug concentration and time-dependent pattern.Cisplatin could up-regulate telomerase activity of Hep-2 cell, which mechanism is not clear.

Seventeen cases of malignant melanoma (MM) were observed with transmission electron microscopy in order to clarify the significance of abberant melanosomes in its diagnosis.30 cases of nevus were also studied to serve as control.It was found that aberrant melanosomes were present in 14 cases of MM including 2 cases of amelanotic MM and absent in 2 cases of pigmented MM and one case of amelanotic MM.In addition,aberrant melanosomes were found in 4 cases of congenital nevus.The findings suggest that the significance of aberrant melanosomes in the diagnosis of MM has been overemphasized.It is believed that the diagnosis of MM must be judged comprehensively on all the ultrastructural changes under transmission electron microscope.

Fifteen cases of malignant melanoma,17 cases of acquired nevus,18 cases of congenital small nevus,and 3 cases of congenital giant nevus were labeled with anti-human prolifera-tive cell antibody Ki-67 with ABC labeling method.It was found that 13 out of the 15 cases of malignant melanoma were positive and the positive rate of the tumor cells was ranged between 2% to 33%.After culture,the positive rate of the melanoma cells was 88%.But all the 3.types of melanocytic nevi were negative.The findings suggest that the labeling of anti-human proliferative cell antibody Ki-67 is a sensitive and specific method to identify melanocytic tumors and it is not sensitive enough to differentiate the minor changes of the 3 types of nevi.

Desmosomes with well-preserved architecture were isloated from the epidermis of bovine muzzle.The thickness of the dense plaque was about 15 nm and the width of desmoso-mal interspace 30~40 nm.The midline in the desmosomal interspace was shown as a moderately electrondense material.The component proteins of the desmosomes were analyzed with SDS-PAGE.It was found that both DP Ⅰ and DP Ⅱ consisted of 3 polypeptides and the molecular weight of DP 1 a,b and c was 235 kd,226 kd and 215kd and that of DP Ⅱ a,b and c was 206 kd,198 kd and 186 kd respectively ; and DP Ⅲ was composed of 2 polypeptides and the molecular weight of DP I a and b was 87 kd and 86 kd.The above mentioned data were different from those of other reports,while the data of the other component proteins were similar to those of others.The molecular weight of DG I was 150 kd.that of DG Ⅱ a and b was 135 kd and 118 kd,that of DG Ⅲ was probably 22 kd.and that of DP Ⅳ was 82 kd.According to our findings,it is concluded that both DP Ⅰ and DP Ⅱ consist of 3 polypeptides and DP Ⅲ of 2 polypepties.

There are controversies concerning whether congential small nevus(CSN)is liable to undergo malignant degeneration and whether it should be resected promptly.The signif-icane of CSN in the pathogenesis of malignant melanoma(MM)was assessed with microspec-trophotometric determination of DNA quantity,the detection of the gene product of N-ras,p21 protein,with ABC technique,ultrastructural study of MM tissue with electron microscopy,and analysis of clinical data of MM.The findings were as follows:(1)The DNA content increased sequentially in order of acquired nevus(AN),CSN,congenital giant nevus(CGN)and MM,and the difference was statistically significant among the 4 groups(P

Objective To investigate the changes of action potential duration (APD) and transient outward K + current (I to) and inward rectifier K + current(I K1) of ventricular myocytes after 3 weeks of myocardial infarction, and to inquire into the effect of bisoprolol. Methods APD was recorded with microelectrode. Ventricular myocytes were singly isolated from rabbit heart using modified Langendoff perfusion and soaked with collagenase. I to and I K1 of single rabbit ventricular myocytes were recorded by whole-cell path-clamp technique. Results Both APD 50 and APD 90 of the cell from noninfarcted region in MI group were markedly longer than that in sham group (P