Objective To select a matrix modifier,which can effectively eliminate the matrix interference in the determination of chromium in cosmetics by graphite furnace atomic absorption spectrometry(GFAAS).Methods The orthogonal experiment design was used to define the best operation parameter of graphite furnace.Vitamin C,(NH4)H2PO4,(NH4)2HPO4,NH4Cl and Mg(NO3)2 were added respectively as the matrix modifiers.The effect of five matrix modifiers was compared by precision test.Results When(NH4)H2PO4 was taken as the chemical modifier,the determination result was satisfied.The characteristic mass was 5.68?10-12 g,relative standard deviation were from 2.11% to 4.46%.The rate of recovery of two cosmetics samples were 95.2% and 102.01%.Conclusion(NH4)H2PO4 can increase the ashing temperature,decrease the atomization temperature,eliminate the matrix interference and the result has good precision and accuracy.

BACKGROUND:Chitosan and sodium hyaluronate are two kinds of anti-adhesion materials commonly used, but there are relatively few reports on their anti-adhesion effects in obstetrics patients. OBJECTIVE:To explore the anti-adhesion effects of chitosan and sodium hyaluronate in obstetric patients. METHODS:Totaly 180 cesarean section patients, aged 23-39 years, were equaly divided into control group, chitosan group and sodium hyaluronate group according to treatment methods. Patients in the control group were given the routine cesarean section; patients in the chitosan and sodium hyaluronate group were respectively given local smearing of chitosan and hyaluronate sodium. At 1 day after operation, the levels of serum interleukin-6, interleukin-10, tumor necrosis factor-α and C-reactive protein were determined in the three groups. Then, the patients were folowed up for 1 month to observe the occurrence of postoperative adhesion and complications. RESULTS AND CONCLUSION:The incidence rate of postoperative adhesions was lower in the chitosan and sodium hyaluronate groups than the control group (P < 0.05). The levels of serum interleukin-6, interleukin-10, tumor necrosis factor-α and C-reactive protein were also lower in the chitosan and sodium hyaluronate groups than the control group (P < 0.05). In addition, the incidence rates of postoperative infection, bleeding and pain were lower in the chitosan and sodium hyaluronate groups than the control group (P < 0.05). However, there was no difference between the chitosan and sodium hyaluronate groups. These findings indicate that the chitosan and sodium hyaluronate are both effective against postoperative adhesions in cesarean section patients, and reduce the incidence of complications.

Objective To evaluate the influence of tracheal intubation guided with light wand on hemodynamics in patients with obstructive sleep apnea syndrome.Methods Seventy-four patients with obstructive sleep apnea syndrome were randomly divided into light wand group (n =37) and laryngoscope group (n =37).The time to successful intubation,rate of successful intubation,changes of heart rate (HR),systolic blood pressure (SBP),diastolic blood pressure (DBP) and complications were compared in two groups.Results The time to successful intubation of light wand group was significantly shorter than that of laryngoscope group,while the rate of successful intubation in light wand group was significantly higher than that in laryngoscope group (P＜0.05).The HR,SBP and DBP at T1 were significantly lower than those at T0 in two groups (P＜0.05).The HR,SBP and DBP in two groups at T2,T3 were significantly higher than those at T1 (P＜0.05),and those indexes of light wand group were significantly lower than laryngoscope group at T2 and T3 (P＜0.05).The incidence rates of complications in light wand group were significantly lower than those in laryngoscope group (P＜0.05).Conclusion With the advantage of higher success rate,shorter time to successful intubation,more stable hemodynamics and fewer complications,tracheal intubation guided with light wand is worthy of popularization and application in clinical.

0.05).Conclusion:The combination of TCM with western medicine was superior to simple western medicine in treating multiple sclerosis.Regulation of cytokines(TNF-? and IL-12 p40) in plasm may be partial reasons for the clinical effects of treatment based on syndrome differentiation.

Amyotrophic lateral sclerosis is a rare but fatal neurodegenerative disorder.Riluzole remains the only available drug for slowing the progression of the disease.In the past few years,significant advances have been made in both our understanding of pathogenesis and the development of new therapeutic approaches.The authors review the current understanding of the pathogeneic mechanisms and drug therapy.The outcome of phase Ⅲ clinical trials will benefit the further investigation in ALS.

BACKGROUND:Better fusion of bone cement and bone interface can reduce prosthesis loosening rate.Marrow cavity is the place where bone cement fusion takes place,so its preparation is important to improve bone cement filling quality.OBJECTIVE:To evaluate bone cement-bone interface fusion in marrow cavity washed with high-pressure pulsed water syringe versus marrow cavity brushing.DESIGN,TIME AND SETTING:The comparative observation was performed at Animal Laboratory and Orthopaedic Laboratory of the First Hospital of Harbin Medical University from July 2002 to June 2003.MATERIALS:Forty fresh horse ulnas were randomly divided into 2 groups(n=20):washing group and control group.METHODS:The articular surfaces of the proximal ulna and cortex of horse ulnas were sawn to expose the trabecular bone,and only 15 cm proximal ulna was retained.The marrow cavity was opened with marrow cavity drilling and marrow cavity file along the line parallel to the longitudinal axis,proximal diameter 1.5 cm,5.5 cm deep,and self-developed marrow cavity bolt was put into the cavity until 5 cm deep.The marrow cavity of washing group was treated with high-pressure washing,1 000 mL fluid for each model,and the cavity was brushed once after washing with every 300 mL fluid for a total of 3 times.At the last time,100 mL water was used to clean the cavity following by wiping until the cavity was dry.The control group was not given any treatment.Both groups were infused with bone cement by the same method,and the models of each group were scanned by CT(interval 4 mm).MAIN OUTCOME MEASURES:Number of trabecular bone closely or not closely connected by bone cement section surrounding to calculate the rate of combination;condition of surfaces of marrow cavity and bone cement in the column by amplifier.RESULTS:CT scanning showed that interface connection rate of washing group was 64.47%,while the control group was 26.67%;the differences were statistically significant(P

Objective To investigate the clinical characteristics and pathogenesis of paroxysmal dyskinesias.Methods Retrospective analysis was performed in 5 patients suffering from paroxysmal kinesigenic choreoathetosis(PKC) and 2 patients with paroxysmal persistent exercise-induced dystonia(PED).Results The episodes of all cases of PKC were induced by sudden movements.3 cases showed rigidty and hypertonia.3 cases presented with twist of limbs and dystonia.2 PED cases were induced by persistent movement,manifested involuntary movements of limbs,and the duration of the attack usually last seconds to minutes.5 patients showed epileptic discharges in EEG or AEEG.2 patients had abnormal findings of brain CT or MRI.4 PKC cases responded well to carbamazepine and 1 PED patients to large dose of valproate sodium.Conclusions Paroxysmal dyskinesias are usually induced by sudden movement and present paroxysmal extrapyramidal symptoms.Most of the patients show epileptic discharges in EEG and responded well to antiepileptic drugs.This implies the underlying relationship of pathogenesis between paroxysmal dyskinesia and epilepsy.

Objective To investigate the pathogenesis of cerebral infarction after non-cardiac surgeries according to imaging.Methods Retrospective analyses of clinical and imaging data of 17 patients with postoperative cerebral infarction(average 68 years old,total incidence 0.049％)from departments of orthopedics and general surgery were conducted during 52 months.Results Cerebral infarction occurred 39.1 hours after operation on average.Among the 17 patients,eight were detected with disturbance of consciousness,ten with hemiplegia,six with speech disorder and two with unilateral sensory disturbance.Six (35.3％)had blood lipids tests.Five(29.4％)had neck vascular ultrasound and one had intracranial magnetic resonance angiography(MRA).When discharged,one patient was declared death and ten had impaired neurological function in various degrees.Among six patients with previous stroke,one(16.7％)received neurological consultation before surgery.According to the image manifestation,ten cases were territory circulation infarcts,four centrum ovale infarcts and three watershed infarcts.Conclusions This study suggests that total incidence of cerebral infarction after non-cardiac surgeries is lower than previously reported and there is greater involvement of atherosclerosis.Patients' conditions should be closely observed within at least four days after surgeries.Preoperative assessment should be strengthened in order to avoid occurrence of postoperative cerebral infarction.

Objective:To determine the effects of silencing glucose regulated protein ( GRP94 ) on the proliferation and apoptosis of breast carcinoma MCF7 cells. Methods:Chemically synthesized siRNA targeting GRP94 gene and transfected into MCF7 cells used by Liopfectamine RNAIMAX. The mRNA and protein expression levels of GRP94,cyclinD1,Bax and Bcl-2 were detected by Real-time PCR and Western blot. CCK8 assay was used to detect the effect of specific GRP94 siRNA on cell proliferation and the effect on cell cycle and apoptosis were analyzed by flow cytometry and Hoechst 33258 staining. Results:Compared with the siRNA-NC cells, the expression of GRP94 was significantly down-regulated in MCF7 cells. Knockdown of GRP94 in MCF7 cells decreased cell proliferation and promoted cell apoptosis. The expression of cyclinD1and Bcl-2levels were significantly reduced, and Bax level was increased in siRNA-GRP94 MCF7 cells. Conclusion: The siRNA-mediated GRP94 silence significantly inhibits MCF7 cell proliferation,promoted cell apoptosis by down-regulating cyclin D1,Bcl-2 expression and up-regulating the Bax expression in MCF7 cells.

Objective To study the relation between mitochondria damage and glutamate excitotoxicity in motor neuron disease.Methods Organotypic cerebral cultures were prepared from prefrontal brain of neonatal SD rats. Mitochondria was damaged by malonate sodium, and a NMDA receptor antagonist, MK-801 of 0.025,0.050,0.075,0.100 mmol/L, was respectively added into the cerebral cultures simultaneously in the protective experiment. The morphology of motor neurons was shown by Nissl and anti-high molecular weight filament (anti-NFH) immunohistochemical staining, and number of motor neurons was counted. The concentration of MDA in culture medium was measured by MDA assay. Results After exposed to malonate sodium (0, 1, 3, 5 and 7 mmol/L) for 1 week, the number of motor neurons in cerebral slices showed a dose-dependent decrease (49.78?4.30, 47.89?6.81, 25.67?6.18, 4.44?3.40, 1.22?1.99). The group treated with 3 mmol/L malonate sodium was selected as damage group. In protective experiment, the number of motor neurons in 0.050, 0.075 and 0.100 mmol/L MK-801-treated groups was significantly increased as compared with damage group, still less than that of controls. However, there was no difference of number of motor neurons among these three groups. The concentration of MDA in culture medium in normal control and 3, 5 mmol/L malonate sodium was (13.47?0.49), (15.87?0.74), (20.52?0.74) mmol/L. When treating cerebral cultures with 0.050 mmol/L MK-801 and 5 mmol/L malonate sodium simultaneously, the MDA was decreased to 14.45?0.78, close to normal level. Conclusion Glutamate excitotoxicity plays a role in motor neuron diseases caused by mitochondria damage, there exists a close relationship between glutamate exicitotoxicity and mitochondria damage.