The application and studies of reduced diameter implants(RDI)are increasing recently.A case with fracture of three 3.3 mm ITI implants in maxilla was reported in this paper.Combined with the related literature,overload,mechanical complications(such as fatigue, crevice corrosion and hydrogen embrittlement)and the insufficiency of mechanical properties of RDI may lead to the fracture.

The pattern of incidence and clin ic al presentation of primary hyperparathyroidism (PHPT) collected during the past 45 years were analysed. It showed that most of PHPT patients were young or mid- aged, and female patients were somewhat more than male patients. The duration of illness was longer and symptoms were more severe. The number of post-menopausa l female patients was increased in recent ten years.

Objective ToinvestigatethementaldevelopmentsituationofpreschoolchildreninTaiyuan. Methods 1174preschoolchildrenoftwourbanareasinTaiyuanwereselected.TheyweretestedwithDenverDevel-opmentScreenTest(DDST).Results Thepassingratewas94.80%in1174children.Theirindividual-social reaction ability and movement ability were good in the three groups.In the subject-touch reaction ability,the passing rate ofvertical tilt at 30°insidewas 36.36%in 4 years old group,which was higher than the other projects.In the speaking ability,the passing rates of three right in four problems with knowing preposition were 15.88% and 27. 22% in 4 and 5 years old group,which were higher than the other projects.The culture degree of the mental retar-dation children's parents were lower than those of the normal children's parents,the difference were statistically signifi-cant(χ2=4.485,P=0.034;χ2=7.577,P=0.006).Conclusion DDSTisaquicklyscreeningmethodformental retardation children,it is suggested to be used in medical and health examination for preschool children.

Objective To study the clinical characteristics of thyroid carcinoma in young females,in order to improve the diagnosis and treatment of this disease.Methods The clinical data of 74 consecutive young female patients with thyroid carcinoma treated in our hospital in the recent ten years were analysed.In most of the cases,there was no firm texture or fixation of the thyroid nodules to surrounding structures on physical examination before operation.Ultrasonography was performed in all patients and multiple thyroid nodules were found in 61 cases(82.43%).Thyroid scintiscans were performed in 43 cases,and thyroid nodules were found in 41 cases.The cold,cool and warm nodules were found in 14,18 and 9 cases,respectively,by scintiscans.Fine needle aspiration biopsy(FNAB) was performed in 11 cases,and in 2 cases were negative,1 case showed abnormal cell,3 cases were suspicious of carcinoma,and 5 cases were confirmed papillary carcinoma.Results Papillary carcinoma was found in 70 cases,follicular carcinoma in 3 cases and medullary carcinoma in 1 case by histological examination,and benign disease was also accompanied in most cases.Lymph node metastases was found in 28 cases(37.84%),and the rate of metastases was significantly different than that of older female patients(16.46%) at the same time.There were 2 cases who died 3 years after operation because of metastases.Conclusions The lymph node metastases were prevalent in young female patients with thyroid carcinoma.The texture and mobility of the nodules cannot be used to differentiate benign from malignant nodules.We should carefully analyze every nodule found on ultrasonography.For the solid nodules with diameter larger than 1.0cm,we suggest operation;for the non-solid nodules with diameter larger than 2.0cm,we prefer scintiscans and FNAB for diagnosis.

2.65 mmol/L with co-elevated PTH. For locating the adenoma, the specificity of B-Us was 95% and the sensitivity of MIBI was 100%. Our standard surgical procedure were bilateral exploration. We found much more tumors in inferior glands than that in superior glands. The success rate in a single exploration in benign cases was 99%. Conclusions PHPT could be diagnosed by co-elevated calcemia and PTH. B-US with 99m Tc-MIBI was the first choice for localization. Bilateral exploration is safe and effective.

Through comparing problem-based learning and lecture-based learning, the PBL teaching can improve the learning interest and self-learning ability of students and also can accomplish the task of teaching better.

BACKGROUND: Although we have gained much information about leadinduced organ damage, the effect of blood lead level on T cell subgroup is yet to be determined.OBJECTIVE: To assess the effect of blood lead level on T cell subgroup of children, and the association of T cell subgroup with threshold limit value of blood lead level.DESIGN: Comparative observation.SETTING: The Institute of Molecular Microorganism, Maternity and Child Care Hospital, Shanxi Provincial Children Hospital.PARTICIPANTS: Sixty children, (32 boys and 28 girls), aged 3-6 years with a mean of (4.5±1.5) years old, were selected from the suburbs of Taiyuan city between May 2003 and October 2003. Informed consents were obtained from all their guardians. The enrolled children according to their blood lead levels were assigned into three groups, 13 in Group Ⅰ with blood lead level ≥ 0.48 μmol/L, 20 in Group 2 with lead level ≥ 0.24 μmol/L but ＜ 0.48 μmoL/L and 27 in Group 3 with lead level ＜ 0.24 μmol/L.METHODS: Blood lead level and expression of T cell subgroup were measured with graphite furnace atomic absorption spectroscopy and immunofluorescence methods respectively. Student t test was used in data analysis, and linear correlation analysis was used to assess the correlation between blood lead level and expression of T cell subgroup.level and expression of T cell subgroup.pression of CD3 and ratio of CD4 to CD8 were lower in Group 1 (lead level ≥0.48 μmol/L) than Group 3 (lead level ＜ 0.24 μmol/L) (t=3.27,blood lead level showed had significant inverse correlation with CD3 expression and the ratio of CD4 to CD8(r=-0.689,-0.674,P ＜ 0.01).CONCLUSION: A blood lead level ≥ 0.48 μmol/L, is shown to significantly decrease the expression of CD3 and ratio of CD4 to CD8 in peripheral blood, which may impair the children's immunological function.

BACKGROUND: Although we have gained much information about leadinduced organ damage, the effect of blood lead level on T cell subgroup is yet to be determined.OBJECTIVE: To assess the effect of blood lead level on T cell subgroup of children, and the association of T cell subgroup with threshold limit value of blood lead level.DESIGN: Comparative observation.SETTING: The Institute of Molecular Microorganism, Maternity and Child Care Hospital, Shanxi Provincial Children Hospital.PARTICIPANTS: Sixty children, (32 boys and 28 girls), aged 3-6 years with a mean of (4.5±1.5) years old, were selected from the suburbs of Taiyuan city between May 2003 and October 2003. Informed consents were obtained from all their guardians. The enrolled children according to their blood lead levels were assigned into three groups, 13 in Group Ⅰ with blood lead level ≥ 0.48 μmol/L, 20 in Group 2 with lead level ≥ 0.24 μmol/L but ＜ 0.48 μmoL/L and 27 in Group 3 with lead level ＜ 0.24 μmol/L.METHODS: Blood lead level and expression of T cell subgroup were measured with graphite furnace atomic absorption spectroscopy and immunofluorescence methods respectively. Student t test was used in data analysis, and linear correlation analysis was used to assess the correlation between blood lead level and expression of T cell subgroup.level and expression of T cell subgroup.pression of CD3 and ratio of CD4 to CD8 were lower in Group 1 (lead level ≥0.48 μmol/L) than Group 3 (lead level ＜ 0.24 μmol/L) (t=3.27,blood lead level showed had significant inverse correlation with CD3 expression and the ratio of CD4 to CD8(r=-0.689,-0.674,P ＜ 0.01).CONCLUSION: A blood lead level ≥ 0.48 μmol/L, is shown to significantly decrease the expression of CD3 and ratio of CD4 to CD8 in peripheral blood, which may impair the children's immunological function.

Objective To evaluate the eff ec t of snail control with niclosamide ethanolamine salt dustable powder (DP) in th e marshland of the Yangtze River ahead of the schedule in spring, and to underst and the impact of the low temperature to molluscicidal effect of the dusting. Methods The snail control test with niclosamide ethanolamine salt dustable powder was carried out under different te mperatures in laboratory. Then the snail control was undertaken in the marshland of the Yangtze River ahead of the schedule in spring, and the molluscicidal ef fect was observed and the temperature changes were also considered. Results When the temperature was 15 ℃ and 25 ℃ respectively, there was no significant difference on the molluscicidal effec t of niclosamide ethanolamine salt DP in laboratory. The average atmosphere temp erature in each day was 8.9-16.3 ℃ from the last ten-day of March to the fir st ten-day of April in Nanjing regions. The corrected mortality of snails and the r educed rates of density of snails were 95.38% and 99.97% respectively on the s ur face of the soil in the marshland field. The corrected mortality and the reduced rates of density of snails were 79.30% and 70.59% respectively in the surface l ayer of the soil. Conclusion The impact of air t emperature is little to the molluscicidal effect of niclosamide ethanolamine sal t DP when the average atmosphere temperature in each day was 10-15 ℃ in the ma r shland of the Yangtze River. If the snail control is undertaken ahead of the sch edule in spring, the reproduction of snails will be suppressed and the infection of Schistosma japonicum will be controlled. [

Objective To determine the de ve lopmental zero and effective accumulated temperature of Oncomela nia eggs under con stant temperature. Methods The eggs were cultur ed under different constant temperature, and their development duration and effe ctive accumulated temperature were studied. The zero accumulated temperature (℃ ) was obtained by using an estimation mode, and the effective accumulated temp erature was obtained by effective accumulated mode of K=N(T-C). [WT5”H Z] Results The average development duration was (27.29?17 .2 9) d under 15-30 ℃, the development zero temperature was 11.79 ℃ and 38.22 ℃ u nder low and high temperature respectively, and the average development temperat ure and effective accumulated temperature were (557.76?198.95) DD and(236 .02 ?68.20) DD.Conclusion The suitable developme nt temperature of eggs is 27 ℃, the development speed and effective accumulated t e mperature of eggs increases with the temperature under given condition, but too high temperature may have negative impact on the development of eggs. The resul t can be considered as the basic biological parameter of the snail.