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Objective To evaluate the role of GABAA receptors in sevoflurane-induced inhibition of the discharge activities of inspiratory neurons in the medullary respiratory center of neonatal rats.Methods The medulla oblongnta slices of neonatal rats (aged 0-4 days) including the medial region of the nucleus retrofacialis with the hypoglossal nerve rootlets retained were prepared.The slices were perfused with artificial cerebrospinal fluid (ACSF),and the activity of the inspiratory neurons in the medial region of the nucleus retrofacialis and the respiratory rhythmical discharge activity of the hypoglossal nerve rootlets were simultaneously recorded using microelectrodes and suction electrodes,respectively.The ACSF,5％ sevoflurane,GABAA receptor blocker bicuculline 10 μmol/L and combination of 5％ sevoflurane and 10 μmol/L bicuculline were added to the perfusion liquid after the discharge activity was stable.The respiratory cycle (RC),inspiratory time (TI),integral amplitude (IA) and changes in peak frequency (PFn) of the inspiratory neurons were recorded.Results Compared with that after giving ACSF,RC was significantly prolonged,TI was shortened,and IA and PFn were decreased after giving sevoflurane,and RC was significantly shortened,IA and PFn were increased (P＜0.05),and no significant change was found in TI after giving bicuculline (P＞ 0.05).Compared with that after giving sevoflurane,RC was significantly shortened,TI was prolonged,and IA and PFn were increased after giving sevoflurane and bicuculline (P＜ 0.05).Conclusion Sevoflurane inhibits the discharge activities of inspiratory neurons through GABAA receptors in the medullary respiratory center of neonatal rats.
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Objective To investigate the effects of different doses of dexmedetomidine on perioperative inflammatory responses in patients undergoing one-lung ventilation (OLV).Methods Thirty-six ASA T or Ⅱ patients (aged 43-72 years and weighing 50-78 kg) scheduled for esophagectomy were randomly divided into three groups (n =12 each):control group (group C),low dose dexmedetomidine group (group D1) and high dose dexmedetomidine group (group D2).Dexmedetomidine 1 μg/kg was infused intravenously 10 minutes before anesthesia induction,then infused at a rate of 0.2 μg· kg-1 · h-1 (group D1) or 0.5 μg· kg-1· h-1 (group D2) until 30 minutes before the end of operation.Group C received the equal volume of normal saline.Blood samples were collected before anesthesia induction (T0),immediately before OLV (T1),30 minutes after OLV (T2),90 minutes after OLV (T3),30 minutes after lung inflation (T4) and 2 hours after operation (T5) for monitoring serumlevels of tumor necrosis factor-alpha (TNF-α) and interleukin-8 (IL-8).Results Compared with T0,serum levels of TNF-α and IL-8 significantly increased at T3 and T5 in all the three groups (P ＜ 0.05).Compared with group C,serum levels of TNF-α and IL-8 significantly decreased at T3 and T5 in group D2 (P ＜ 0.05).There was no significant difference in the indexes mentioned above between group C and group D1 (P ＞ 0.05).Conclusion Dexmedetomidine 1 μg/kg given before anesthesia induction and then infused at the rate of 0.5 μg· kg-1 ·h-1 during operation can reduce inflammatory responses in patients undergoing OLV.
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Objective To investigate the effect of doxapram on inhibition of medullary respiratory center excitability by sevoflurane in rats.Methods Neonatal Sprague-Dawley rats of both sexes,aged 1-4 days,were used in this study.Isolated medulla oblongata-spinal cord specimens were made according to the method described by Suzue and perfused with the artificial cerebrospinal fluid saturated with 95％O2-5％CO2.The specimens were randomly divided into 3 groups ( n =9 each):control group (group C),sevoflurane group (group S) and sevoflurane + doxapram group (group S + D).Respiratory rhythmical discharge activity of the hypoglossal nerve rootlets was recorded using suction electrode.After 10 min of equilibration,the specimens were perfused with the artificial cerebrospinal fluid,5％ sevoflurane and the mixture of 5％ sevoflurane and 5 μmol/L doxapram for 10 min in groups C,S,and S + D respectively.The respiratory cycle,inspiratory time and integral amplitude of inspiratory discharge were recorded.Results Compared with group C,the respiratory cycle was significantly prolonged,the inspiratory time was significantly shortened,and the integral amplitude of inspiratory discharge was significantly decreased in group S (P ＜ 0.05),and no significant change was found in the parameters mentioned above in group S + D (P ＞ 0.05).Compared with group S,the respiratory cycle was significantly shortened,the inspiratory time was significantly prolonged,the integral amplitude of inspiratory discharge was significantly increased in group S + D ( P ＜ 0.05).Conclusion Doxapram antagonizes sevoflurane-induced inhibition of excitability of medullary respiratory center in rats.
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The postoperative recurrence rate of gastrointestinal cancer is high. The therapeutic effect of traditional chemotherapy is not satisfactory, such as chemotherapy through vein and intestine perfusion and so on, and the side effects are obvious. In recent years, researchers in and abroad have begun to study the effect of intraperitoneal chemotherapy. Whether early postoperative intraperitoneal chemotherapy affect the healing of anastomotic stoma is still controversial. Intraperitoneal chemotherapy combined with medicine can achieve a better therapeutic effect. This article reviewed current issues of intraperitoneal chemotherapy, espe-cially its validity and safety.
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Objective To investigate the effects of heparanase and E-cadherin on the invasion and metastasis of gastric cancer. Methods Fifty specimens of gastric cancer which had been resected at Cancer Hospital of Liaoning Province from February 2005 to May 2007 were collected. The expression of heparanase mRNA and E-cadherin mRNA in these gastric cancer specimens was detected by RT-PCR, and the expression of E-cadherin in these gastric cancer specimens was detected by immunohistochemistry. Data were analyzed by t-test and variance analysis, and the enumeration data analyzed by chi-square test. Results There were significant differences in the expression of heparanase and E-cadherin between gastric cancer cells with high and low differentiation, presence and absence of metastasis, and TNM stages Ⅰ and Ⅱ versus Ⅲ and Ⅳ (t = 1.999, 4.258, 1.735 ; 1.286, 6.794, 3.091; χ~2 =6.273, 9.397, 5.640, P <0.05). The co-expression of heparanase (+) and E-cadherin (-) was correlated with tumor undifferentiation, lymph node metastasis and advanced TNM staging (χ~2 =11.306, 10.208, 8.420, P <0.05). Conclusions Heparanasc shows high expression while E-cadherin shows low expression in gastric cancer tissue. There is a synergistic effect between the abnormal expression of heparanase and E-cadherin, and the gastric cancer cells with coexpression of heparanase and E-cadherin have more malignant potential.
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Background and purpose:Hereditary nonpolyposis colorectal cancer(HNPCC) which related to inheritance is an autosomal dominant inheritance.There are many screening standards differing presently from country to country.The Amsterdam standard is internationally recognized.These screening standards are just based on family history and clinical manifestations which can not reflect the essence of the disease.At present,the golden standard for screening HNPCC is mismatch repair genes detection that is in the experimental stage.The purpose of this study was to investigate the expression of mismatch repair genes hMSH2 and hMLH1 in HNPCC and their clinicopathological signif icance,and to fi nd a simple,fast and economic method for screening HNPCC.Methods:Immunohistochemical staining was used to detect the expression of hMSH2 and hMLH1 in 20 cases with HNPCC(Group A),20 cases with ordinary hereditary colorectal cancer(Group B),20 cases with sporadic colorectal cancer(Group C),and 20 cases with colorectal polyps(Group D).Results:The expression rates of hMSH2 and hMLH1 in Group A,B,C and D were 35%(7/20),70%(14/20),95%(19/20) and 100%(20/20) respectively,which illustrated that the probability of HNPCC and the negative expression of hMSH2 and hMLH1 was reduced from Group A to Group D.There were signifi cant differences among these groups(P0.05).Conclusion:The negative expression of hMSH2 and hMLH1 was signifi cantly correlated with HNPCC and location and differentiation of colon carcinoma.Immunohistochemical staining may be useful for screening HNPCC.
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Objective To investigate demographic and clinical features of hereditary nonpolyposis colorectal cancer (HNPCC) in Chinese patients.Methods Data of 45 HNPCC pedigrees diagnosed in accordance with Armsterdam I and Armsterdam Ⅱ Criteria were collected and analyzed.Results In 264 patients, 305 malignant neoplasms were found.The median age of confirmed diagnosis of HNPCC was 50 years.Out of the 305 primary cancer foci, 180 were colonic cancers (59%), 125 were extracolonic cancer (41%) with carcinoma of the lung, endometrium and stomach accounting for 24.0% (30/125), 14.4% (18/125), and 12.0% (15/125) respectively.Conclusion HNPCC is characterized by early vertical transmission, with extracolonic cancer, and synchronous multiple and/or metachronous multiple primary cancers as common clinical features. Carcinoma of the lung, endometrium and stomach are among the most common extracolonic malignancies.