Effect of appetite-conditioned reflex stimulation on early enteral nutrition tolerance after surgery.

OBJECTIVE: This study aimed to discuss the effects of appetite-conditioned reflex stimulation on the early enteral nutrition (EEN) tolerance, complications, and postoperative hospital stay in patients who underwent surgery. METHODS: Seventy patients who underwent laparoscopic radical resection of colorectal cancer surgery in our hospital between February and December 2017 were randomly divided into a stimulated appetite group (experimental group, including visual stimulation, nasal stimulation, taste stimulation and hearing stimulation) and a control group (n = 35). Both groups received EEN. EEN tolerance, complications, and postoperative hospital stay were then compared between the groups. RESULTS: Sixty-six patients, including 34 in the experimental group and 32 in the control group, completed the relevant experiment. The experimental group had significantly lower incidence rates of nausea, vomiting, bloating, use of prokinetic drugs, and gastric tube replacement (P < 0.05), and shorter tolerable regular eating time (5.0 ± 1.0 d vs 6.4 ± 1.9 d, P < 0.05) and postoperative hospital stay (7.0 ± 2.0 d vs 8.0 ± 1.8 d, P < 0.05) than the control group. No significant difference in complication rate was detected (P > 0.05). CONCLUSION: Appetite-conditioned reflex stimulation can improve EEN tolerance, decrease the risk of complications, and shorten ordinary diet recovery time and hospital stay.

[Comparison of the clinical application of three-dimensional and two-dimensional laparoscopic pancreaticoduodenectomy].

Objective: To compare the clinical application of three-dimensional laparoscopic pancreatoduodenectomy (3D-LPD) with that of two-dimensional laparoscopic pancreatoduodenectomy (2D-LPD), and to explore the safety and feasibility of 3D-LPD. Methods: A retrospective analysis was made from the data of 45 patients with 3D-LPD and 45 patients with 2D-LPD who underwent total laparoscopic pancreatoduodenectomy from March 2017 to August 2018 at Department of Hepato-Pancreato-Biliary Surgery, the First People's Hospital of Changzhou.The differences of intraoperative conditions, postoperative complications and postoperative pathological findings between the two methods were compared.Measurement data were compared with independent sample t-test, enumeration data were statistically analyzed with Chi-square test or Fisher exact probability. Results: The operation time of 3D-LPD group was shorter than that of 2D-LPD group ((335±95) min vs. (419±113) min, t=-3.817, P=0.000), which mainly showed that the time of digestive tract reconstruction was reduced ((92±26) min vs. (131±46) min, t=-4.951, P=0.000). The intraoperative blood loss in the 3D-LPD group was significantly less than that in the 2D-LPD group ((242±124) ml vs. (350±176) ml, t=-3.365, P=0.001), and the perioperative blood transfusion in the 3D-LPD group was significantly less than that in the 2D-LPD group (χ(2)=4.444, P=0.035). Postoperative hospitalization days and ICU stay time were not significantly different between the two groups(both P>0.05). Postoperative complications such as pancreatic fistula, biliary fistula, postoperative bleeding, gastric emptying disorders, abdominal infection, were not significantly different between the two groups(all P>0.05). Conclusions: The operation time of 3D-LPD is shorter than that of 2D-LPD, and the amount of bleeding is less. Short-term clinical data showed that, 3D-LPD is effective, safe and worth popularizing.

Effect of rituximab combined with chemotherapy on the expression of serum exosome miR-451a in patients with diffuse large b-cell lymphoma.

OBJECTIVE: The aim of this study was to investigate the influence of rituximab combined with chemotherapy on the expression of serum exosome micro ribonucleic acid 451a (miR-451a) in patients with diffuse large B-cell lymphoma (DLBCL), and to explore the possible underlying mechanism. PATIENTS AND METHODS: 89 DLBCL patients (DLBCL group) receiving rituximab combined with chemotherapy were enrolled in this study. Meanwhile, 48 healthy controls (control group) were enrolled as well. Serum samples were collected from all patients before and after treatment, respectively. At the same time, blood samples of healthy people were collected, and serum exosome was extracted. Real-Time fluorescence-quantitative Polymerase Chain Reaction (qRT-PCR) was applied to measure the expression level of serum exosome miR-451a. Receiver operating characteristics (ROC) curve was used to evaluate the diagnostic efficiency of miR-451a. Statistical Product and Service Solutions (SPSS) 22.0 was employed for statistical analysis. Two-sided 95% confidence interval (CI) was used for all tests, and p<0.05 was considered statistically significant. RESULTS: The expression level of miR-451a in the DLBCL group was significantly lower than that of the control group. The area under the ROC curve (AUC) for the diagnostic efficacy of serum exosome miR-451a for DCBCL was 0.7147. After treatment, the level of serum exosome miR-451a in patients was significantly increased, whereas was still lower than the normal level. The AUC of ROC for evaluating the effect of serum exosome miR-451a in DCBCL was 0.8038. CONCLUSIONS: Serum exosome miR-451a has moderate diagnostic efficiency for DLBCL. Moreover, miR-451a can act as an indicator for evaluating the efficacy of rituximab combined with chemotherapy in the DLBCL treatment.

Predictive factors for central lymph node and lateral cervical lymph node metastases in papillary thyroid carcinoma.

BACKGROUND: Central lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) is common. But the association between primary tumor characteristics and specific features of metastatic lymph nodes in PTC has not been fully identified. Determining risk factors for LNM may help surgeons determine rational extent of lymph node dissection. METHODS: Data from 432 patients who underwent thyroidectomy with cervical lymph node dissection for PTC were retrospectively analyzed. The relationships between LNM to central compartment or lateral compartment and clinicopathologic factors were analyzed. Cox regression model was used to determine the risk factors for recurrence-free survival (RFS). RESULTS: Central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) were found in 216 (50.0%) and 65 (15.0%) patients, respectively. In the multivariate analysis for CLNM, patients < 45 years of age (OR 2.037, 95% CI 1.388-2.988, P < 0.001), extrathyroidal invasion (OR: 2.144, 95% CI 0.824-5.457, P = 0.011), vascular invasion (OR 13.817, 95% CI 1.694-112.693, P = 0.014), LLNM (OR 2.851, 95% CI 1.196-6.797, P = 0.014) and TNM Stage III-IV (OR 465.307, 95% CI 113.903-1900.826, P < 0.001) were independent predictors for high prevalence of CLNM. In the multivariate analysis for LLNM, tumor size more than 1cm (OR 3.474, 95% CI 1.728-6.985, P < 0.001) and CLNM (OR 5.532, 95% CI 2.679-11.425, P < 0.001) were independent predictors for high prevalence of LLNM. Moreover, tumor with T3-T4 stage, extrathyroidal invasion and CLNM were the significant factors related to the RFS. CONCLUSION: For patients with pre-operative risk factors of LNM, an accurate preoperative evaluation of central compartment or lateral compartment is needed to find suspicious lymph nodes. And prophylactic lymph node dissection should be performed in patients with high risk of CLNM. Moreover, we suggest performing close follow-up for patients with high risk of RFS.

[Preoperative C-reactive protein/albumin ratio predicts the prognosis of patients with resectable pancreatic cancer].

Objective: To evaluate the clinical significance of C-reactive protein/albumin ratio in predicting the postoperative prognosis of pancreatic cancer patients. Methods: The clinical date of 97 patients with resectable pancreatic cancers who treated at Department of Hepatobiliary and Pancreatic Surgery, the third Affiliated Hospital of Soochow University from January 2005 to December 2015 were analyzed retrospectively. The cut-off value of CRP/Alb ratio was determined by the receiver operating characteristic(ROC) curve. According to the CRP/Alb ratio, patients were respectively divided into two groups: the high group(CRP/Alb ratio≥0.109) and the low group(CRP/Alb<0.109). The relationships between CRP/Alb ratio and clinical characteristics were analyzed by χ(2) test. Median survival and 1-year overall survival rate(OS) was calculated by Kaplan-Meier method.The risk factors of patients with poor prognosis were analyzed by univariate and multivariate Cox regression analysis model. Results: Tumor TNM stage(χ(2)=4.280, P=0.039) and differentiation(χ(2)=6.635, P=0.010) had significant relationship with CRP/Alb ratio. The median survival of higher CRP/Alb ratio group and lower CRP/Alb ratio group was 15 months and 23 months respectively. Compared with lower CRP/Alb ratio group, the 1-year OS of higher CRP/Alb ratio group decreased remarkablely, and the difference was statistically(χ(2)=10.207, P=0.001). Moreover, median survival and OS were decreased in patients with advanced age(≥65 years old: χ(2) =5.338, P=0.021), high TNM stage(ⅡB-Ⅲ: χ(2) =10.529, P=0.001), poor tumor differentiation(χ(2)=5.380, P=0.020), vascular invasion(χ(2) =7.856, P=0.005) and positive surgical margin(χ(2)=9.059, P=0.003). A high CRP/Alb ratio was identified as an independent risk factor of poor prognosis for patients with pancreatic cancer(HR=1.832, 95% CI: 1.067-3.144, P=0.028). Besides, old age(HR=1.684, P=0.014), high TNM stage(HR=1.666, P=0.031), vascular invasion(HR=1.834, P=0.024) and positive surgical margin(HR=2.205, P=0.023) were also included. Conclusion: Preoperative CRP/Alb ratio can be an important clinical factor for assessing the prognosis of patients with resectable pancreatic cancers, and high CRP/Alb ratio suggests poor prognosis.

Dual-wavelength passively Q-switched Nd:GYSGG laser by tungsten disulfide saturable absorber.

A dual-wavelength passively Q-switched Nd:GYSGG laser using vacuum evaporating tungsten disulfide (WS2) as a saturable absorber was demonstrated for the first time to the best of our knowledge. The WS2 saturable absorber was prepared simply by evaporating nanometer WS2 powders onto a quartz substrate in a vacuum. By inserting the WS2 saturable absorber into the laser cavity, stable Q-switched laser operation was achieved with a maximum average output power of 367 mW, a pulse repetition rate of 70.7 kHz, the shortest pulse width of 591 ns, and pulse energy of about 1.05 µJ. By vacuum evaporation method, a high-quality WS2 saturable absorber can be produced, and it seems to be a suitable method for fabrication of 2D transition metal dichalcogenides.

[Interaction between passive smoking and folic acid supplement during pregnancy on autism spectrum disorder behaviors in children aged 3 years].

OBJECTIVE: To explore the interaction between passive smoking and folic acid supplement during pregnancy on children autism spectrum disorder(ASD)behaviors. METHODS: Children aged about 3 years were enrolled at kindergarten entrance in Longhua district of Shenzhen in 2014. Self-administered questionnaires were completed by their primary caregivers and the information about children' s age, gender, history of preterm birth and low birth weight, parents' education level, parents' reproductive age and family income were collected. The children ASD behaviors were assessed with Autism Behavior Checklist(ABC). According to the cut point of ABC, the children were divided into normal group with score less than 31, sub-clinical group with score ranging from 31 to 61 and suspect clinical group with score no less than 62. After controlling for potential confounders, multivariate logistic regression analysis was performed to evaluate the main effects and the interaction between passive smoking and folic acid supplement during pregnancy on children ASD behaviors. RESULTS: Maternal passive smoking during pregnancy was significantly associated with children ASD behaviors(sub-clinical group: OR=1.48; suspect clinical group: OR= 2.85), and maternal folic acid supplement during pregnancy was not related to children ASD behaviors(sub-clinical group: OR=1.04; suspect clinical group: OR=0.75). Stratified analysis showed that folic acid supplement during pregnancy was negatively associated with children ASD behaviors(suspect clinical group: OR=0.30)among children without mothers' passive smoking during pregnancy, and that mothers' passive smoking during pregnancy was positively associated with children ASD behaviors(sub-clinical group: OR=1.52; suspect clinical group: OR=4.45)among the children whose mothers had folic acid supplement during pregnancy. Furthermore, an interaction effect on children ASD behaviors was found between passive smoking and folic acid supplement during pregnancy(suspect clinical group: OR=5.30). CONCLUSION: Passive smoking and folic acid supplement during pregnancy were related to children ASD behaviors and had an interaction on children ASD behaviors.

TEM characterization of dislocations in TiB2 particles after hypervelocity impact.

Characteristic of dislocations in TiB2 particles associated with hypervelocity impact craters in 65 vol.% TiB2/Al composite were investigated by transmission electron microscopy (TEM). Two kinds of dislocation networks in as-impacted TiB2 particles were identified. One is hexagonal dislocation networks including 1/3〈1̄21̄0〉, 〈0001〉, 1/3〈1̄21̄3〉 type dislocations on {0001}, {101̄0}, and {123̄0} planes. Another one is the hexagonal dislocation networks including 1/3〈112̄0〉, 〈0001〉, and 1/3〈112̄3〉 type dislocations on {0001}, {101̄0}, and {11̄00} planes. Formation of dislocation network should be contributed to the parallel sets of "a" type dislocations (1/3〈112̄0〉 or 1/3〈1̄21̄0〉 type dislocations) reacting with parallel sets of "b" type dislocations (〈0001〉 type dislocations) to form "c" type dislocations (1/3〈112̄3〉 or 1/3〈1̄21̄3〉 type dislocations). Moreover, dislocations reaction processes do not result in an energy reduction, and are called quasi-equilibrium configurations. Formation of dislocations may result from high temperature or pressure generated by hypervelocity impact. During the cooling from high temperature and unloading from high pressure, dislocations in TiB2 particles rearranged and transformed to dislocation networks to lower the defect energy.

Quantum criticality in electron-doped BaFe2-xNixAs2.

A quantum critical point is a point in a system's phase diagram at which an order is completely suppressed at absolute zero temperature (T). The presence of a quantum critical point manifests itself in the finite-T physical properties, and often gives rise to new states of matter. Superconductivity in the cuprates and in heavy fermion materials is believed by many to be mediated by fluctuations associated with a quantum critical point. In the recently discovered iron-pnictide superconductors, we report transport and NMR measurements on BaFe(2-x)Ni(x)As2 (0≤x≤0.17). We find two critical points at x(c1)=0.10 and x(c2)=0.14. The electrical resistivity follows ρ=ρ0+AT(n), with n=1 around x(c1) and another minimal n=1.1 at x(c2). By NMR measurements, we identity x(c1) to be a magnetic quantum critical point and suggest that x(c2) is a new type of quantum critical point associated with a nematic structural phase transition. Our results suggest that the superconductivity in carrier-doped pnictides is closely linked to the quantum criticality.

Microstructure characterization of Al matrix composite reinforced with Ti-6Al-4V meshes after compression by scanning electron microscope and transmission electron microscope.

Compressive properties of Al matrix composite reinforced with Ti-6Al-4V meshes (TC4(m)/5A06 Al composite) under the strain rates of 10(-3)S(-1) and 1S(-1) at different temperature were measured and microstructure of composites after compression was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Compressive strength decreased with the test temperature increased and the strain-rate sensitivity (R) of composite increased with the increasing temperature. SEM observations showed that grains of Al matrix were elongated severely along 45° direction (angle between axis direction and fracture surface) and TC4 fibres were sheared into several parts in composite compressed under the strain rate of 10(-3)S(-1) at 25°C and 250°C. Besides, amounts of cracks were produced at the interfacial layer between TC4 fibre and Al matrix and in (Fe, Mn)Al(6) phases. With the compressive temperature increasing to 400°C, there was no damage at the interfacial layer between TC4 fibre and Al matrix and in (Fe, Mn)Al(6) phases, while equiaxed recrystal grains with sizes about 10 µm at the original grain boundaries of Al matrix were observed. However, interface separation of TC4 fibres and Al matrix occurred in composite compressed under the strain rate of 1S(-1) at 250°C and 400°C. With the compressive temperature increasing from 25°C to 100°C under the strain rate of 10(-3) S(-1), TEM microstructure in Al matrix exhibited high density dislocations and slipping bands (25°C), polygonized dislocations and dynamic recovery (100°C), equiaxed recrystals with sizes below 500 µm (250°C) and growth of equiaxed recrystals (400°C), respectively.

Residual microstructure associated with impact crater in Ti-6Al-4V meshes reinforced 5A06Al alloy matrix composite.

In this paper, TC4(m)/5A06Al composite was hypervelocity impacted by 2024 aluminium projectile with the diameter of 2mm and with the impact velocity of 3.5 km/s. The residual microstructure was observed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HREM). The TC4-Al interface before impact was composed of TiAl(3) phase and Ti(3)Al phase. Near the pithead, separation of TC4 fibers and Al matrix occurred along the impact direction. Around the middle of the crater, TC4 fibers were sheared into several sections. Near the bottom of crater, adiabatic shear band (ASB) occurred in TC4 fiber, while the angle between shear plane and cross section was 45°. The crack propagated along TC4-Ti(3)Al interface during impact and some Ti(3)Al phase at the TC4-Al interface transformed to amorphous with few nanocrystals after hypervelocity impact.

SEM and TEM characterization of the microstructure of post-compressed TiB2/2024Al composite.

In the present work, 55 vol.% TiB(2)/2024Al composites were obtained by pressure infiltration method. Compressive properties of 55 vol.% TiB(2)/2024Al composite under the strain rates of 10(-3) and 1S(-1) at different temperature were measured and microstructure of post-compressed TiB(2)/2024Al composite was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). No trace of Al(3)Ti compound flake was found. TiB(2)-Al interface was smooth without significant reaction products, and orientation relationships ( [Formula: see text] and [Formula: see text] ) were revealed by HRTEM. Compressive strength of TiB(2)/2024Al composites decreased with temperature regardless of strain rates. The strain-rate-sensitivity of TiB(2)/2024Al composites increased with the increasing temperature. Fracture surface of specimens compressed at 25 and 250°C under 10(-3)S(-1) were characterized by furrow. Under 10(-3)S(-1), high density dislocations were formed in Al matrix when compressed at 25°C and dynamic recrystallization occurred at 250°C. Segregation of Mg and Cu on the subgrain boundary was also revealed at 550°C. Dislocations, whose density increased with temperature, were formed in TiB(2) particles under 1S(-1). Deformation of composites is affected by matrix, reinforcement and strain rate.

Residual microstructure associated with impact craters in TiB2/2024Al composite.

Residual microstructures associated with hypervelocity impact craters in 55 vol.% TiB(2)/2024Al composite were investigated by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). TiB(2)-Al interface, TiB(2) particles and Al matrix before and after hypervelocity impact were compared to discuss the effect of hypervelocity impact. A new Al(x)O(1-x) phase with the fcc structure and the crystal parameter of 0.69 nm was formed at TiB(2)-Al interface. Stacking fault with width of 10-20 nm was formed along the (001) plane of TiB(2) particle. Formation of nanograins (≈ 100 nm) was observed within Al matrix, moreover, lamellar S' phase was transformed into lenticular or spherical S phase after hypervelocity impact.

Superconductivity-induced optical anomaly in an iron arsenide.

One of the central tenets of conventional theories of superconductivity, including most models proposed for the recently discovered iron-pnictide superconductors, is the notion that only electronic excitations with energies comparable to the superconducting energy gap are affected by the transition. Here, we report the results of a comprehensive spectroscopic ellipsometry study of a high-quality crystal of superconducting Ba0.68K0.32Fe2As2 that challenges this notion. We observe a superconductivity-induced suppression of an absorption band at an energy of 2.5 eV, two orders of magnitude above the superconducting gap energy 2Δ≈20 meV. On the basis of density functional calculations, this band can be assigned to transitions from As-p to Fe-d orbitals crossing the Fermi level. We identify a related effect at the spin-density wave transition in parent compounds of the 122 family. This suggests that As-p states deep below the Fermi level contribute to the formation of the superconducting and spin-density wave states in the iron arsenides.

Specific heat measurements of Ba(0.68)K(0.32)Fe2As2 single crystals: evidence for a multiband strong-coupling superconducting state.

The specific heat of high-purity Ba(0.68)K(0.32)Fe2As2 single crystals with the highest reported superconducting Tc=38.5 K was studied. The electronic specific heat Cp below Tc shows two gap features, with Δ1≈11 meV and Δ2≈3.5 meV obtained from an α-model analysis. The reduced gap value, 2Δ(max)/kBTc≈6.6, the magnitude of the specific-heat jump, ΔCp(Tc)/Tc, and its slope below Tc exhibit a strong-coupling character. We also show that an Eliashberg model with two hole and two electron bands gives the correct values of Tc, the superconducting gaps, and the free-energy difference.

Self-energy effects and electron-phonon coupling in Fe-As superconductors.

Doping and temperature dependent studies of optical phonon modes in Fe-122 pnictides are performed using Raman scattering experiments and compared with model calculations to elucidate the role of electron-phonon and spin-phonon interaction in this family of compounds. The frequency and linewidth of the B(1g) mode at around 210 cm(-1) is highlighted as appreciable anomalies at the superconducting and spin density wave transitions are observed that strongly depend on composition. We give estimates of the electron-phonon coupling related to this renormalization and calculate the phonon self-energy on the basis of a four-band model comparing different symmetries of the order parameters. In addition, we observe a pronounced quasi-elastic Raman response for the undoped compound, suggesting persisting magnetic fluctuations in the spin density wave state.

Intervalence (charge-resonance) transitions in organic mixed-valence systems. Through-space versus through-bond electron transfer between bridged aromatic (redox) centers.

Intervalence absorption bands appearing in the diagnostic near-IR region are consistently observed in the electronic spectra of mixed-valence systems containing a pair of aromatic redox centers (Ar(*)(+)/Ar) that are connected by two basically different types of molecular bridges. The through-space pathway for intramolecular electron transfer is dictated by an o-xylylene bridge in the mixed-valence cation radical 3(*)(+) with Ar = 2,5-dimethoxy-p-tolyl (T), in which conformational mobility allows the proximal syn disposition of planar T(*)(+)/T redox centers. Four independent experimental probes indicate the large through-space electronic interaction between such cofacial Ar(*)(+)/Ar redox centers from the measurements of (a) sizable potential splitting in the cyclic voltammogram, (b) quinonoidal distortion of T(*)(+)/T centers by X-ray crystallography, (c) "doubling" of the ESR hyperfine splittings, and (d) a pronounced intervalence charge-resonance band. The through (br)-bond pathway for intramolecular electron transfer is enforced in the mixed-valence cation radical 2a(*)(+) by the p-phenylene bridge which provides the structurally inflexible and linear connection between Ar(*)(+)/Ar redox centers. The direct comparison of intramolecular rates of electron transfer (k(ET)) between identical T(*)(+)/T centers in 3(*)(+) and 2a(*)(+)( )()indicates that through-space and through-bond mechanisms are equally effective, despite widely different separations between their redox centers. The same picture obtains for 3(*)(+) and 2a(*)(+)( )()from theoretical computations of the first-order rate constants for intramolecular electron transfer from Marcus-Hush theory using the electronic coupling elements evaluated from the diagnostic intervalence (charge-transfer) transitions. Such a strong coherence between theory and experiment also applies to the mixed-valence cation radical 7(*)(+), in which the aromatic redox S center is sterically encumbered by annulation.

[Interstitial tubercle in Chinese and Japanese young adults]

A comparative study on the incidence of interstitial tubercle from standardized stone casts of 160 Chinese and 190 Japanese young adults,ages from 20-30.The following results were obtained:(1)No significant difference in the incidence of interstitial tubercle on maxillary first premolar between Chinese and Japanese groups(P>0.05),but on maxillary second premolar,Japanese is higher than Chinese(P<0.05).(2)The incidence of interstitial tubercle on maxillary first premolar is higher than second premolar in two groups(P<0.05).(3)The intestitial tubercle occurs in unilateral more frequently than in bilateral.The incidence of maxillary first premolar in mesial of occlusal is higher than in distal.No difference between mesial and distal on occlusal of maxillary second premolar in the Chinese group,and the incidence in mesial is higher than in distal in the Japanese group.

[Morphological study on occlusal grove of mandibular molar of Chinese adults]

During human evolution,the morphology of mandibular molar occlusal grooves have changed from the pattern "Y" to pattern "+".Six types of occlusal grooves were classified as:Y5,Y4,+5,+5,X5 and X4. Using computer analysis,we get the result.(1)The rate of "Y5" in first mandibular molar is the highest,the rate of "X4" is the lowest.(2)The rate of "+4" in second mandibular molar is the highest,while the rate of "Y5" is the lowest. (3)The rates of each type groove between male and remale have no significant difference.Our conclusion coincides in the evolution of human mandibular molar,that is helpful to direct the clinic and anthropology study.

[A comparative morphologic study of Carabelli cusp between Chinese and Japanese students.].

The study of teeth,dentition and occlusion is helpful to guide oral medical clinic and the study of anthropology.Our department of Osaka Dental University and had many items of research work about teeth,dentition and occlusion between Chinese and Japanese students.This article reports the study of Carabelli cusp.The results revealed:(1)the rate of Carabelli cusp is higher in Japanese than in Chinese and is higher in male than in female.(2)the rate of Carabelli cusp of the first maxillary molar of both side is very high.(3)The rate of Carabelli cusp is related to the height and the type of cusp numbers.These all illustrated the occurence of Carabeiil cusp were influenced by race, individual and the development of teeth.