This article expounds the indication,preoperative ischemic tolerance test,evaluation of collateral circulation,different surgical modes,complications and their prevention in the treatment of intracranial aneurysms during extracranial-intracranial(EC/IC)graft bypass.It is considered that EC/IC bypass graft is an effective therapeutic mode in preventing the occurrence of cerebral ischemia in the treatment of intracranial aneurysms.

Purpose of this study is to re-compute and analyze the hospitalization rates of residents in China and explore the methodology of systematic review in health policy research.Methodology:DThanks to a history of 90 years,USMLE has evolved into a mature system of international recognition in the industry.This paper covers the history and changes of USMLE and details its goals construction and implementation,examination question selection model,procedures and principles,selection of criteria and the development trends.

Objective To investigate surgical techniques and results of arthroscopic reduction and fixation for the treatment of avulsion fracture of the posterior cruciate ligament from the tibia through an additional posterolateral portal. Methods An additional posterolateral portal was established by using the inside-out technique under arthroscopic view.After a protective sleeve was placed through the portal and the displaced fracture was reduced,the fragment was fixed by the guide wire drilled through the sleeve temporarily.If the fluoroscopic control showed an anatomic reduction of the fragment and good placement of the wire,the self-attacked cannulated screw and washer was placed intra-articularly over the guide wire through the sleeve for the directive internal fixation of the avulsion fracture.Aggressive rehabilitation programs were recommended postoperatively.Results Except 1 case with 11 mm displacement and rotation of the fragment treated by the arthrotomy after the failure of arthroscopic reduction,the arthroscopic operation was accomplished in all the remaining 10 cases.The operative time was 63～98 min(mean,87.3 min).No injuries of popliteal vessels or nerves occurred.The postoperative X-ray firms showed an anatomic reduction of the fragment and good placement of the screw and washer.With the negative posterior drawer test confirmed by the physical examination,normal range of motion of the injured knee joint and gait were achieved in the 10 patients at 4～7 weeks after surgery.The bone union was confirmed by X-ray films at the 3 months postoperatively.The computer KT-2000 arthrometer measurements of posterior tibial displacement of both knee joints showed side-to-side difference not more than 1.2 mm in 6 patients at 5 months after surgery.Conclusions The additional posterolateral portal can be established by the arthroscopic inside-out technique safely.The displaced fragment of the avulsion fracture of the posterior cruciate ligament from the tibia can be reduced and fixed with the self-attacked cannulated screw and washer arthroscopicly.

Objective:To evaluate the results of repairing furcation and root perforation using Mineral Trioxide Aggregate(MTA).Methods:Cases with furcation perforations were divided into two groups randomly,MTA and IRM(control group)methods were adopted in present study.Cases that had root perforations were treated with MTA.Pretreatment,immediate posttreatment,and 1year follow-up radiographs were evaluated in a double-blind manner to determine the presence or absence of any pathologic changes adjacent to the perforation site.Results:21 cases were involved.The healing rate of furcation perforation in MTA group was higher(80%)when compared with that in IRM group(75%).However,statistical analysis showed no significant difference in success rates between both groups(P=0.722).The healing rate of root perforation using MTA was 100%.Conclusion:MTA provides an effective seal of furcation /root perforations,and promises in improving the prognosis of perforated teeth.

Objective To explore the methods of breeding ,reproduction and genotype of GJB2 knock -out (cCx26KO) mice and further study the critical role of GJB2 mutation in the onset of nonsyndromic hearing loss (NSHL) .Methods Two pairs of transgenic mice (Cx26loxp/loxp and Pax2 -Cre/+ ) were inbreeded to produce Cx26loxp/-_Pax2-Cre/+ ones ,female of which were used to mate with the male Cx26loxp/loxp ones to finally get the Cx26loxp/loxp_Pax2 -Cre/+ mice(cCx26KO) .The genotype was done by PCR and Agarose gel electro-phoresis using genome DNA extracted from the mice tails .The c-ABR was used to detect the hearing ability of the cCx26KO mice .Results Both breeding and reproduction of cCx26KO mice were successful .It was fruitful to obtain four genotype mice(Cx26loxp/loxp_ Pax2-Cre / + ,Cx26loxp / -_Pax2-Cre / + ,Cx26loxp/loxp ,Cx26loxp /-) by the breeding Cx26loxp / -_Pax2Cre / + and Cx26loxp/loxp mice .The results of breeding were met with the Mendel's law .The c-ABR revealed elevated response threshold around 95 dB SPL in cCx26KO mouse compared to the wild type ones ,which further validated the accuracy of the PCR method .Conclusion The PCR method is cor-rectly identified sub pups genotype and the female Cx26loxp/-_Pax2-Cre/+ mice mating with the male Cx26loxp/loxp ones is an effective way to obtain the cCx 26KO mice .

BACKGROUND: It is indistinct that whether ketamine can exert antinociceptive effect througb influencing the transmission of nocuous information in spinal cord; Nitric oxide (NO) in spinal cord participates mainly in the formation and development of hyperalgesia, and it can also induce Fos protein expression. It is still controversal whether it contributes to the transmission and mediation of ketamine to pain signal.OBJECTIVE: To observe the response to formalin stimulation in spinal cord of the rats and the effect of ketamine.DESIGN: Balanced randomized animal trial.SETTING: Department of Anesthesiology, Affiliated Hospital of Xuzhou Medical College; Jiangsu Provincial Key Laboratory of Anesthesiology.MATERIALS: This trial was carried out in the Jiangsu Provincial Key Laboratory of Anesthesiology, Xuzhou Medical College from January to March 2000. Totally 30 Sprague-Dawley rats were chosen and balanced randomized into 6 groups: formalin group (n=6), formalin + ketamine group (n=6), ketamine +formalin group (n=6), ketamine group (n=6), formalin+normal saline group (n=3) and normal saline group (n=3). The gender ratio was the same in each group.METHODS: Formalin group:The rats were stimulated for one hour by subcutaneous injection of 0.05 volume fraction of 200 μL in the center of palm of unilateral fore-claw. Formalin +ketamine group: The rats were stimulated for 10 minutes by formalin, then for one hour by intraperitoneal injection of 100 rg/kg ketamine. Ketamine + formalin group: The rats were injected with ketamine for 10 minutes, then with formalin for one hour. Ketamine group: the same dosage of ketamine was intraperitoneally injected into the rats for one hour. Formalin + normal saline group: The rats were stimulated for 10 minutes by formalin, then intraperitoneally given 10 mL/kg normal saline for one hour. Normal saline group: the same volume of normal saline was intraperitoneally injected into the rats for one hour.MAIN OUTCOME MEASURES: ① Behavioral performance of the rats in each group. ② Spinal sections were chosen, and stained with c-fos genetic immunohistochemical and NADPH-d histochemical methods. The changes of the number of Fos-like immuno-positive neurons (FLI) and FLI/nitric oxide synthase (NOS) double-labeled neurons in the 4-layer sections (layer Ⅰ -Ⅱ ,layer Ⅲ-Ⅳ ,layerⅤ-Ⅵ ,layer Ⅶ-X )of spinal dorsal horn of the rats were observed.RESULTS: All the thirty rats entered the stage of result analysis. ① Behavioral changes: The rats of formalin group and formalin+ normal salinegroup had apparent pain response; Several minutes after injection with ketamine, righting reflex disappeared and did not recover at perfusion period.Prolonged sleep was found without obvious pain response performance. ② FLI neuron expression: A lot of FLI positive neurons were found in the spinal dorsal horn of injec tion side of the rats in the formalin group and formalin+ normal saline group, and they distributed principally in the layer Ⅰ - Ⅱ of spinal dorsal horn.The distribution in the ketamine + formalin group and formalin + ketamine group was basically similar to that in the formalin group and formalin + normal saline group, but positive neuron counts were significantly reduced (P ＜ 0.01). ③ The expression of FLI/NOS double-labeled neurons: The number of double-labeled neurons in the spinal dorsal horn layer Ⅰ - Ⅱ of the rats in the ketamine+ formalin group and formalin+ ketamine group were significantly less than that in the formalin group and formalin+normal saline group [(1±1), (1±1), (7±3), (8±3),P ＜ 0.01].CONCLUSION: Some neurons of ipsilateral corresponding spinal segments participate in the transmission and mediation of pain signal. Ketamine can suppress the activities of these neurons and exert antinociceptive effect. The antinococeptive function of ketamine may be caused by the activity depression of the NOS-positive neurons in spinal cord.

OBJECTIVE:To establish HPLC method for simultaneous determination of estazolam and diazepam in serum METHODS:The mobile phase consisted of methanol-water-triethylamine-acetic acid(55∶45∶0 5∶0 35)and the ?max was 254nm Phenytoin was adopted as the internal standard The drugs were extracted by diethyl ether under the alkaline condition RESULTS:The calibrating curves of estazolam and diazepam were linear in the ranges of 0 52～38 62?g/ml and 0 50～40 16?g/ml respectively CONCLUSION:The method was appropriate for determination of estazolam and diazepam qualitatively and quantitatively in intoxication accident

ObjectiveTo study the chemical constituents of Citrullus colocynthis.MethodsThe chemical constituents were isolated and purified by column chromatography on silica gel and Sephadex LH-20 and recrystallization as well.NMR spectra and physicochemical property were characterized for structural identification.ResultsEleven compounds wereisolatedandidentifiedasβ-sitosterol(1), α-spinasterol-3-O-β-D-glucopyranoside(2),α-spinasterone (3),bis (2-ethylhexyl) phthalate (4),p-hydroxybenzoic acid (5),6-C-p-methylbenzoylvitexin (6),dihydrocucurbitacin E (7),cucurbitacin E (8),dihydro-epi-iso-cucurbitacin D (9),dihydroisocucurbitacin B-25-acaetate (10),and cucurbitacin E 2-O-β-D-glucopyranoside (11).ConclusionCompound 6 is a novel compound.Compounds 1-5,7,9,and 10 are isolated from C.colocynthis for the first time.

AIM:To study the protective effects of penehyclidine hydrochloride(PHC) on transient forebrain ischemia reperfusion injury in gerbils.METHODS:The model of transient forebrain ischemia reperfusion was established in gerbils by bilateral carotid artery clamping.The effects of PHC on neurological function scores and the morphous of hippocampal pyramidal neuron of gerbils were observed after receiving transient forebrain ischemia reperfusion.SOD activities and contents of MDA in the hippocampus and cortex of gerbils were measured.RESULTS:In the groups of PHC(0.08),(0.24)(mg?kg~(-1)) and atropine,the stroke index was decreased,compared with the ischemia-reperfusion group after the gerbils received transient forebrain ischemia reperfusion for six hours.PHC could reduce the degree of injury in hippocampal pyramidal neuron after ischemia reperfusion for three days.CONCLUSION: PHC has protective effects on transient forebrain ischemia reperfusion injury in gerbils.

AIM To investigate the protective effect of sodium gamma-hydroxybutyrate (?-OH) against cerebral ischemia-reperfusion injury in gerbils and the neuroprotective mechanism of ?-OH. METHODS The occlusion of bilateral carotid arteries of gerbil was used to make the cerebral ischemia-reperfusion models. Different doses of ?-OH were administered intraperitoneally 40 min prior to the onset of ischemia. After 10 min ischemia and 1 h reperfusion, bilateral hippocampus, cortex and striatum were taken out to measure ATPase, SOD and MDA. RESULTS The contents of MDA markedly elevated while Na +,K +-ATPase, Ca 2+ -ATPase and SOD activities decreased in hippocampus, cortex and striatum 1 h after ischemia-reperfusion. ?-OH administered prior to ischemia can partly reverse the elevation of MDA contents and the reduction of SOD activities. ?-OH given after ischemia can still provide partly protective effect. CONCLUSION ?-OH provides significant protective effect against cerebral ischemia-reperfusion injury by protecting ATPase and SOD activities, deleting free radicals and reducing the lipid peroxidation.