Objective To evaluate the sentinel lymph node biopsy (SLNB) in clinical lymph node negative oral squamous cell carcinoma. Methods Sentinel lymph node biopsy (SLNB) by using methylene blue staining were employed to 20 patients with clinical cervical lymph node negative in oral squamous cell carcinoma. Results SLNB was successful identified in 14 of 20(70%). A 100%(6/6) accuracy of SLNB to predict cervical lymph node status was reached. Conclusion SLNB could accurately predict the cervical status of clinical negative node and decrease the extent of surgery and postoperative complication

Objective To investigate the nutritional status of vitamin D in preterm infants after birth and further explore its possible influencing factors, so as to guide clinical vitamin D therapy and to screen the preterm infants who are at high risk of vitamin D deficiency.Methods Retrospective analysis was conducted in the neonatal department of our hospital from April 21st, 2014 to February 5th, 2016.The serum 25(OH)D level in preterm infants were measured 2 weeks after birth.Data including gender, season of birth, time to initiation of breastfeeding were collected.According to the 25(OH)D levels[25(OH)D≤37.5 nmol/L, 37.5 nmol/L≤50.0 nmol/L, and 25(OH)D>50.0 nmol/L], all the preterm infants were divided into three groups: vitamin D deficiency, insufficiency, and sufficiency groups.The influencing factors of vitamin D in preterm infants were screened by using statistical method.Results The mean 25(OH)D level of 172 preterm infants was (43.1±16.7)nmol/L.In vitamin D deficient, insufficient, and sufficient groups, there were 68 (40％), 50 (29％) and 54(31％) cases of preterm babies, respectively.The mean values of 25(OH)D in these three groups were (27.8±16.7)nmol/L, (42.4±3.4)nmol/L, and (63.0±11.7)nmol/L, respectively.Only the season of birth had significant difference among three groups (P=0.013): 44.2％ of the preterm infants born in winter had vitamin D deficiency, which was higher than those in spring (41.7％), summer(33.3％), and autumn (38.1％);44.2％ of the preterm infants born in winter had vitamin D insufficiency, which was much higher than those in spring (30.6％), summer (25.1％), and autumn (19.0％);furthermore, only 11.6％ of the preterm infants born in the winter had vitamin D sufficiency, which was much lower than those in spring (27.8％), summer (41.2％), and autumn (42.9％) (OR=4.655, 95％ CI=1.716-12.627, P=0.003).Conclusion Vitamin D deficiency in preterm infants 2 weeks after birth is prevalent, and winter birth is a risk factor of vitamin D deficiency and insufficiency in preterm infants.