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 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.

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.

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.

Objective Laboratory tests of yeast, with their disadvantages of long identification, complicated operation, and low positive rate, cannot meet the needsof rapid diagnosis and timely treatment.This studyinvestigated the feasibility ofapplying matrix-assisted laser desorption ionization-time of flight mass spectrometry ( MALDI-TOF-MS) in rapid identification and clinical isolationof yeast strains. Methods A total of 120 clinical non-repetitive isolates were collected from clinical culture samples and identified by MALDI-TOF-MS and VITEK 2-Compact/API, respectively.The discordant results were resolved by ITS gene sequencing. Results Of the 120 yeast isolates analyzed, 117 (97.5%) were correctly identified at the species level by MALDI-TOF-MS, 1(0.8%) misidenti-fied, and 2 ( 1.7%) unidentified.ITS gene sequencing of the 3 isolates showed the coincidence rate to be 0( 0/3) for MALDI-TOF-MS and Vitek 2-Compact/API. Conclusion MALDI-TOF-MScan be used as a rapid, accurate, and inexpensive tool for the identification of clinical yeast strains.

Objective To study the impact of environmental temperature on the development of Schistosoma japonicum larvae within the Oncomelania hupensis. Methods Oncomelania snails, collected from the field and free of S. japonicum infection, were exposed to miracidiae of S. japonicum in a ratio of 1∶20 and raised at 30 ℃, 27 ℃, 24 ℃, 21 ℃ and 18 ℃, respectively. The prepatent period of larvae within the Oncomelania hupensis and the developmental velocity were determined, of which the relationship with the temperature was analysed. Results The average prepatent period of cercariae in snail was (128.89?16.05) d,(95.00?21.03) d,(71.93?12.74) d and (62.74?14.19) d at 21 ℃, 24 ℃, 27 ℃, 30 ℃, respectively. The regression formulation between prepatent period and temperature was y =730.68x -0.8918 (r=0.9976, P

Objective To understand the distribution and fluctuation tendency of infected Oncomelania snails in marshland areas of Jiangsu Province in order to provide the scientific basis for acute schistosomiasis control. Methods In each county(city, district) 5-10 marshland areas with snails were sampled randomly, and of which 5-10 sites were selected. Fifty to one hundred snails were collected in each site and dissected by professionals to determine the natural infection rate. At the same time, the mollusiciding actions were carried out in the schistosome-positive snail sites and beaches. Results In 5 years, a total of 467 beaches have been checked and 102 positive beaches were find out and the snails detected. The positive rate of beaches was 21.84%(102/467). A total of 169200 snails were dissected , and of which 433 were positive snails. The natural infection rate was 0.2559%(433/169200). The infested areas and the number of positive snails in 2002 were 2.71 and 18.33 times of those in 1998 in Jiangsu Province. Conclusion In the continuous 5 years observation, the tendency of the population of positive snails and the infested areas were significantly growing, and there is a apotential threat for the acute infections. So, the keys of the following work should be controlling snails seriously in the marshlands and the rivers in connection with the Yangtze River, increasing the mollusiciding cover rate and improving the quality in the positive beaches, and surveying and treating the cattle time by time.

Objective To understand the impact of environmental temperature on the infection of miracidia of Schistosoma japonicum to Oncomelania snails, and to estimate the lowest critical temperature for infection of snails with miracidia. Methods Oncomelania snails free of S.japonicum were collected from field,and exposed to miracidia at the ratio of 1∶20 under the different temperatures, such as 5,6,8,10,15,20℃.Snails were dissected to check if infected after exposured and kept in 25℃ for another 70 days. Results The infection rate of snails were 0,0.92,1.43,2.40,8.96,17.39% under the temperature of 5,6,8,10,15,20℃, respectively. The relationship between snail infection rate and temperature for infection was showed in the regression formulation of y=0.0622x 2-0.4035x+0.6703 (r=0.9988,P