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AIM: To investigate the preventive effects of Clostridium butyricum (C. butyricum) on the type of pylorus ligated gastric ulcer (GU) in mice and the underlying mechanisms. METHODS: ICR mice were randomly divided into 4 groups: sham operation group, model group, C. butyricum pretreatment group and omeprazole pretreatment group. Gastric pyloric ligation was adopted to establish GU model in mice. The gastric juice was collected to measure the content of gastric free mucus, the pH of gastric juice and the activity of pepsin. The gastric tissues were collected for routine HE staining to observe the pathological changes. The content of glycogen was detected by PAS staining. The protein expression of Bax and Bcl-2 in the gastric mucosa was also assessed by immunohistochemical staining. RESULTS: The HE and PAS staining showed that the C. butyricum pretreatment obviously attenuated the mucosa lesion induced by ligation. Compared with model group, the pH of gastric juice was significantly raised. The activity of pepsin fell off in C. butyricum group, which was lower than that in omeprazole group. In comparison with model group, the content of gastric free mucus was dramatically increased and PAS staining showed a significant rise in C. butyricum group, but not in omeprazole group. The protein expression of Bax was decreased and the protein expression of Bcl-2 was upgraded in C. butyricum group than those in model group. CONCLUSION: C. butyricum protects gastric mucosa against the challenge of pylorus ligation in mice and its mechanism may be related to inhibiting gastric acid secretion and the activation of pepsin, increasing the production of gastric free mucus, strengthening the expression of bcl-2 gene and inhibiting the expression of bax gene.  相似文献   
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AIM: To characterize the hemoperfusion of abdominal organs in the early stage of sepsis in mice. METHODS: Health male Kunming mice were used in the study (n=100). The techniques of 2D, M-mode and pulse-wave Doppler were applied to evaluate the systolic functions of the heart and the blood flow of abdominal aorta, right renal artery and portal vein before cecal ligation and puncture (CLP) as the baseline and at the time points of 12 h, 24 h, 36 h, 48 h and 60 h after CLP. The mice survived for 7 d were considered as survivals. All data were compared with the baseline values.RESULTS: The cardiac output of the CLP mice remained in normal or hyperdynamic levels in the early stage of sepsis. Compensatory responses of systolic functions were observed. The levels of blood flow in abdominal aorta were increased first and then decreased. Resistent index (RI) and pulsatility index (PI) of abdominal aorta began to increase at the time point of 24 h. Blood flow of right renal artery showed a significant decline from the beginning to the end of our observation. No significant difference of the right arteriorenal RI and PI was observed. Portal venous flow increased significantly at 12 h, and decreased at 24 h after CLP. Congestion index of the portal vein was distinctly increased from 12 h to the end of the observation. CONCLUSION: The hemodynamics of abdominal organs in early stage of septic mice shows specific changes, indicating an important role in evaluating the mechanism of sepsis.  相似文献   
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OBJECTIVE: To compare bursting tension of arteries > or =3 mm in diameter sealed with ultrasonic energy (UE) with arteries ligated with suture. STUDY DESIGN: Experimental, nested factorial design. SAMPLE POPULATION: Vascular segments from canine cadavers. METHODS: Arterial segments (12) were collected from each of 16 canine cadavers and equally divided into 2 groups based on vessel diameter (medium, 3.0- < 4.5 mm; large, 4.5 - < or =6.0 mm). Arterial specimens (3) from each group were sealed with either UE (Harmonic Scalpel, HS, power level 3) or suture ligation. The mean bursting pressure and tension were determined and compared. RESULTS: Bursting tension was significantly higher (P< .0001) for sutured arteries than UE-occluded arteries, irrespective of size. Bursting tension was significantly higher (P=.0013) for medium than large UE-occluded arteries, whereas there was no difference associated with size for ligated arteries. UE energy failed to seal 1 medium artery and 7 large arteries. Compared with normal blood pressure, bursting pressures were 3.5 times greater for sutured arteries irrespective of size, 1.8 times greater for medium UE-occluded arteries, and approached normal blood pressure for large UE-occluded arteries. CONCLUSION: At the power level tested, UE should not be used to seal arteries > 4.5 mm in diameter. Suture provided an optimal seal for arteries < or =6.0 mm in diameter. CLINICAL RELEVANCE: Use of UE to occlude arteries during laparoscopic surgery is advantageous because only 1 instrument is required to simultaneously cut and coagulate tissue, but care should be exercised where large arteries might be encountered.  相似文献   
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选取5种动物为试验对象,生理年龄均在1/2性成熟期,每种动物4头,猪(长白,70 d)、羊(小尾寒羊,60 d)、狗(比格犬,80 d)、兔(日本大耳白,75 d)和鸡(爱拔益加,75 d)。采用体内原位结扎灌注肠段的方法研究不同浓度大豆凝集素(SBA)在不同种属动物小肠中的残留、结合和内吞特点。动物禁食24 h后,注入麻醉剂,剪去腹部体毛,打开腹腔,结扎空肠前段,(各种动物以空肠前段1/3处相对位置开始结扎)。用30 m L(39±1)℃的生理盐水冲洗隔离的肠段,以冲洗肠段内残余的食糜,分别结扎4段5 cm长的肠段,用注射器分别输入含不同浓度SB(A 0、0.5、1.0 m g/m L和3.0 m g/m L)的Krebs液。灌注时间8 h。试验结束后,采用间接抑制ELISA方法检测3个指标:灌注液中SBA的残留率,肠黏膜表面SBA的结合率,进入小肠壁的SBA的内吞率。结果表明:大豆凝集素在动物小肠中的结合特点存在种属差异;比较而言,SBA在猪和狗小肠中的内吞率和结合率高于羊,兔和鸡的内吞率也较大,且SBA的不同浓度对其在小肠壁上的内吞也有较大影响,低浓度时SBA的结合率和内吞率较大。  相似文献   
5.
Ultrastructural alterations of pancreatic tissues in growing pigs caused by surgical ligation of the main pancreatic duct are described. Five animals aged 6 to 7 weeks were operated on and necropsied 2, 6 or 8 weeks later. In addition, 3 pigs that were sham-operated served as controls. Obstruction of the ducts caused progressive luminal dilatations and rupture of intercellular connections of the epithelium followed by destruction and atrophy of acinar parenchyma and proliferations of immature ductular epithelial cells free from zymogen granules.  相似文献   
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Castration is one of the most common surgical procedures performed in equines and is associated with various complications, such as severe hemorrhage and evisceration. Using clinical, hormonal, and histopathological findings, this study aimed to evaluate a novel in situ castration technique and compare it with two other in situ techniques, namely, “section–ligation–release” (SLR) and “pinhole” (PH), to choose the most compatible and safe technique for sterilizing donkeys. Fifteen adult male donkeys were divided into three groups (five animals each). The vascular and the nonvascular parts of the spermatic cord were double ligated separately after opening the skin and the tunica vaginalis at the scrotal neck in the first group (incision–ligation [IL] technique, IL group). In the second group, donkeys were subjected to in situ castration using SLR technique, where both parts of the spermatic cord were triple clamped, ligated, and transected (SLR group). In the third group, percutaneous ligation of the spermatic vessels was performed without opening the skin (PH technique, PH group). The PH technique was less effective and failed to induce necrosis in the testes in situ. Also, Testosterone hormone levels remained elevated 60 days after this procedure. Although the IL and SLR techniques result in convincing reductions in resting and human chorionic gonadotropin–stimulated testosterone levels in treated donkeys, IL and SLR techniques were conducted under narcosis and strict asepsis. We concluded that the PH technique should not be recommended for sterilizing donkeys. Meanwhile, the IL and SLR techniques can be considered as an alternative to other conventional methods used for sterilizing donkeys.  相似文献   
9.
Objective To determine the outcome and effect of a partial ligation of the transposed parotid duct at the level of the parotid gland in four dogs with excessive salivation and ocular irritation. Methods Four dogs were previously diagnosed with absolute keratoconjunctivitis sicca. After a parotid duct transposition (PDT) surgery, these dogs experienced excessive saliva production and abundant salivary precipitates, which resulted in epiphora, moist dermatitis, blepharospasm, and keratitis. In an effort to decrease saliva production, a partial ligation of the transposed duct at the level of the parotid gland was performed. Two or three accessory branches to the primary parotid duct were ligated at the level of the salivary gland. Results The four cases were three Yorkshire terriers and a Chihuahua. The average age of the four patients was 2.5 years. Partial ligation of accessory branches of the parotid duct at the level of the parotid gland after a PDT in this study demonstrated improved ocular comfort, decreased salivary precipitates, and adequate Schirmer tear test results without marked epiphora in three of the four animals. The male Yorkshire had epiphora after the initial partial ligations of two accessory branches were placed at the level of the parotid gland. To correct the excessive salivary flow, two additional ligatures were placed at a later date, which resolved the epiphora. Conclusion Partial ligation of the parotid duct at the level of the parotid gland proved to be an effective technique in moderating the salivation in these four patients with excessive salivary secretions after PDT.  相似文献   
10.
随着基因功能的深入研究,构建表达载体是研究各基因的功能及其相互关系的第一步。近年来涌现的多种同源重组介导的高效克隆策略极大地方便了载体的构建。简要综述了同源重组介导的克隆方法的研究进展,及其在载体构建中的应用。  相似文献   
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