Objective To optimize the dose distribution of postoperative brachytherapy for linear keloids,and to investigate the effects of the number of radiation sources n,source-to-skin distance d,and source spacing a on dose distribution,thereby providing a reasonable radiation source arrangement scheme for radiotherapy in narrow and elongated wound areas.Methods A one-dimensional idealized model was established.Based on the inverse-square law,dose distributions were calculated under combinations of differentn(4,6,8,10)and d(from 0.3 to 2.0 cm).The proportions of dose-effective areas(90%-110%of the prescribed dose)and penumbra areas(20%-80%of the prescribed dose)were analyzed to evaluate the rationality of dose distribution.Results When d/a slightly exceeded 0.5,the proportion of the effective area reached its peak,and the proportion of the penumbra area was relatively low.An excessively small d/a led to cold spots in the irradiated area,while an excessively large d/a expanded the penumbra area.Increasing n significantly reduced the penumbra range and improved dose homogeneity.Conclusion The dose distribution is most reasonable when d/a is slightly greater than 0.5,and a multi-source arrangement(n≥6)is preferred to enhance dose homogeneity.This study provides guidance for parameter optimization in brachytherapy for keloids.

Objective To optimize the dose distribution of postoperative brachytherapy for linear keloids,and to investigate the effects of the number of radiation sources n,source-to-skin distance d,and source spacing a on dose distribution,thereby providing a reasonable radiation source arrangement scheme for radiotherapy in narrow and elongated wound areas.Methods A one-dimensional idealized model was established.Based on the inverse-square law,dose distributions were calculated under combinations of differentn(4,6,8,10)and d(from 0.3 to 2.0 cm).The proportions of dose-effective areas(90%-110%of the prescribed dose)and penumbra areas(20%-80%of the prescribed dose)were analyzed to evaluate the rationality of dose distribution.Results When d/a slightly exceeded 0.5,the proportion of the effective area reached its peak,and the proportion of the penumbra area was relatively low.An excessively small d/a led to cold spots in the irradiated area,while an excessively large d/a expanded the penumbra area.Increasing n significantly reduced the penumbra range and improved dose homogeneity.Conclusion The dose distribution is most reasonable when d/a is slightly greater than 0.5,and a multi-source arrangement(n≥6)is preferred to enhance dose homogeneity.This study provides guidance for parameter optimization in brachytherapy for keloids.

Objective To explore the characteristics of calcifying pseudoneoplasm of the neuraxis ( CAPNON) , and to improve the di-agnostic level and standard of treatment. Methods The clinical traits, imaging features and curative effect of one case of CAPNON who were treated in our departmen were analyzed combined with the pathological analysis and literature review. Results Transient back pain was the only clinical presentation of the patient. CT images showed obvious calcification. MRI showed low signal in T1-weigthed images and T2-weighted images. Examined with the contrast-enhanced MR images, the lesion showed inhomogeneous enhancement. No nervous symptom newly occurred in the 6-month follow-up. Conclusion Symptoms of patients with CAPNON are generally related to local compression or irri-tation of the adjacent tissue. CAPNON should be highly suspected in patients with dense calcification in the CT combined with low signal in T1-weigthed images and T2-weighted images and rim or internal inhomogeneous linear enhancement in the MRI. The final diagnosis depends on the histopathological analysis, and surgical resection is the major therapy.

Objective To study the relationship and prognosis between E-cadherin gene expression and lymphatic hyperplastic reaction in gastric cancer. Methods The degree of lymphocytosis and draining lymph node from 86 cases of gastric cancer were observed and the expression of E-cadherin gene in gastric cancer were detected by SP method of immunohistochemistry (IHC). Results Lymphocyte infiltration degree around gastric cancers was positively related to the reactive hyperplasia of the lymphnodes and was inversely related to lymphatic metastasis. The expression of E-cadherin has relationship with the infiltration degree of stomach carcinoma. To compare with T1/T2 and T3/T4 phases, the result is significantly different (P ＜0.01).Meanwhile, the expression of E-cadherin was positively correlated with tumor-infiltrated lymphocytes and reactive hyperplasia of the lymph nodes, was negatively correlated with lymphatic metastasis in drainage area.Conclusion The over-expression of E-cadherin gene is significantly related to lymphoproliferation and lymph node metastasis. The abnormal expression of E-cadherin can be used as an index to determine prognosis of gastric carcinoma.

Objective To evaluate the diagnostic value of expression of MG7-Ag diflferentiation and guidance of follow-up mucosal biopsy in the patients with suspected malignanct gastric ulcer.Methods The expression of MG7-Ag in 58 patients who were suspected as having malignant gastric ulcer under routine endoscopy was studied by immuno-histochemical staining.The follow-up endoscopy was pefformed 1 to 72 weeks(mean 7 weeks)later and biopsy was taken.Results There were 19 cases of gastric carcinoma in 30 patients with positive MG7-Ag expression(63.3%)and only 5 in 28 patients with negative MG7-Ag expression(P＜0.01).Conclusion The positive expression of MG7-Ag is correlated with gastrie carcinoma in patients with suspected malignant gastric ulcer.

0 05].The sensitivities in pSS patients with lower lip biopsy and in pSS patients without lower lip biopsy were 88 3% and 84 6% respectively.The total sensitivity was 87 0% and the specificity was 97 8%.At least 11 2% of pSS patients with negative anti SSA/SSB antibodies were diagnosed by lower lip biopsy.Conclusion The new international classification criteria for pSS are feasible in Chinese patients.It has a high sensitivity of 87 0% and a high specificity of 97 8% which may serve as diagnosis criteria in routine clinical practice

Twenty- five patients with severe head injury underwent early total parenteral nutrtion (TPN) support,and the blood glucose,serum albumin,body nutritional index and nitrogen balance were monitored in our case- controll study.We find that the patients with severe head injury could get more energy and protein from TPN than from enteral nutrition (EN) ,the mortality of the patients with TPN was significantly lower than the patients with EN.The total nutrient admixture(TNA) in our study can provide sufficient energy and protein,but cannot raise blood glucose,so it can make a good condition for the recovery of the severe head injuries.