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101.
Coagulation system and platelets play an important role in the stage of lodgement of tumor cells. We examined abilities of human and hamster pancreatic cancer cell lines to aggregate platelets in vitro, and investigated the effect of prostaglandin E1, I2, on artificial liver metastases of pancreatic cancer in Syrian golden hamster. Platelet aggregating activities were found in five out of six human pancreatic cancer cell line and thromboplastin likes activity in five cell lines. Diisopropanolnitrosamine induced hamster pancreatic cancer cells (HPK-1) were able to aggregate platelets both in vitro and in vivo and these activities were inhibited by prostaglandin I2. Hamster was inoculated intraportally with 1 X 10(6) HPK-1 cells. After two weeks autopsy of these hamsters revealed multiple metastatic nodules on liver surface. In this model we administered prostaglandin E1, I2 into the portal vein five minutes before cell inoculation. Number of liver surface nodules were significantly decreased to 33.1 + 7.0, 11.0 + 9.6 in hamster given 100g PGE1 PGI2 before cell inoculation, compared with control group of hamsters (62.0 + 6.6 PH9.3, 66.1 + 13.9 PH7.4). But administration of prostaglandin after cell injection was not effective. In all cases none of extrahepatic metastases were noted. Inhibitory action of PGE1 PGI2 on liver metastasis is suspected to be related to inhibition of platelet aggregation.  相似文献   
102.
H Saito  K Sato  H Tomioka 《Tubercle》1988,69(3):187-192
In vitro antimicrobial activity of rifabutin and rifampicin against various mycobacteria, including the Mycobacterium avium complex, was evaluated by the agar dilution method, using 7H10 agar medium. The activity of rifabutin based on MIC50 and MIC90 was higher than that of rifampicin, against all the acid-fast organisms tested. Microbicidal activity of rifabutin against the M. avium complex phagocytosed in mouse peritoneal or alveolar macrophages was greater than that of rifampicin. Both rifabutin and rifampicin had therapeutic effects against murine infections induced by M. avium complex. Rifabutin was somewhat more effective than rifampicin in mice.  相似文献   
103.
Summary Gulonolactone oxidase, a key enzyme in the biosynthesis of ascorbic acid, is missing from guinea pigs and certain other scurvy-prone species. Weekly intraperitoneal injections of glutaraldehyde cross-linked immunoprecipitates of this enzyme have been shown to provide guinea pigs with the capability of synthesizing their own ascorbic acid and of surviving without an exogenous source of this vitamin. This protocol, however, was successful in only a small percentage of the animals tested. The reasons for the limited therapeutic success were investigated. Apparently, the gulonolactone oxidase-treated guinea pigs fed without ascorbic acid were receiving insufficient nutrition. By supplementing these enzyme-treated animals with vitamins A, B, D and E and selenium, we successfully maintained a high proportion of guinea pigs fed without vitamin C.  相似文献   
104.
In order to elucidate the physiological significance of plasma dopamine, blood pressure, pulse rate (PR), plasma concentrations of free or conjugated dopamine (free or conjugated pDA), noradrenaline (pNA) and adrenaline (pAd) were measured in 9 healthy volunteers. Blood sampling for the measurements was performed at a basal condition maintaining a supine position for 60 minutes, after twenty minutes 60 degrees head-up tilt (tilt) and an intravenous infusion of 1000 ml 0.9% saline for 2 hours. Following tilt, mean values in diastolic and mean blood pressure, PR, pNA and pAd were significantly increased, while free, conjugated and total pDA were decreased. On the other hand, saline infusion yielded significant decreases in hematocrit, pNA, free, conjugated and total pDA, but blood pressure, PR and pAd remained at the same level. Free/conjugated pDA ratio did not change during tilt or saline infusion. The basal value of free, conjugated or total pDA did not significantly correlate with blood pressure, PR, pNA or pAd, respectively. Furthermore, no significant correlations between the changes in pDAs and hemodynamic parameters, pNA or pAd by tilt or saline infusion were observed. From these results, it was suggested that plasma free or conjugated dopamine in physiological conditions may not be released from sympathetic nerve endings or adrenomedullary glands. Further investigations are needed to clarify the physiological significance of plasma dopamine in humans.  相似文献   
105.
This study was conducted to compare the midline incision right retroperitoneal approach for repairing abdominal aortic aneurysms (AAA) with the transperitoneal approach. The intra- and postoperative course of 15 patients who underwent AAA repair using the transperitoneal approach between 1987 and 1991 and another 15 patients who underwent AAA repair using the retroperitoneal approach between 1991 and 1994 were evaluated. The incidence of postoperative wound complications was also assessed. There was no operative or hospital death in either group. Although a significantly longer interval was required from the incision to the aortic clamp using the extraperitoneal method, there were no statistical differences in the aortic clamping time, total operation time, or blood loss between the two groups. On the other hand, there was a statistically significant improvement in bowel function and a significant reduction in the length of postoperative hospitalization following the extraperitoneal procedure. Furthermore, no wound complications such as those associated with the left flank incision developed after the extraperitoneal procedure. Thus, we recommend the midline incision right retroperitoneal approach for AAA as it does not involve muscle division and is associated with fewer complications.  相似文献   
106.
A 52 year-old woman noticed general fatigue, polyarthralgia, and muscle weakness of lower extremities in October 2001. In December, she felt difficulty in walking due to muscle weakness. In January 2002, she admitted another hospital because of dyspnea on exertion and edema of lower extremities. Laboratory test revealed leukocytopenia, the elevation of creatine kinase and positive anti-U1-RNP antibodies. Her chest computed tomography (CT) showed severe interstitial pneumonia. Cardiac echogram revealed that she had pericardial effusion and pulmonary hypertension. Then she was transferred to Keio University Hospital and she was diagnosed as having mixed connective tissue disease (MCTD) manifestating myositis, interstitial pneumonia, pulmonary hypertension and pericarditis. Prednisolone (PSL) 60mg daily following to methylprednisolone (mPSL) pulse therapy was begun and her symptoms were gradually improved. In middle of February, she complained of high fever over 39.0 degrees C. Bacterial culture tests were negative and laboratory data indicated pancytopenia and a high level of serum ferritin. Bone marrow aspiration revealed hemophagocytosis in bone marrow specimens and she was diagnosed as having hemophagocytic syndrome associated with MCTD. mPSL pulse therapy was not effective and intermittent cyclophosphamide pulse therapy (IV-CY) was performed resulting in improvement of the symptoms. This case suggested the effectiveness of IV-CY therapy in patients with corticosteroid-resistant HPS associated with connective tissue diseases.  相似文献   
107.
We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound (20 MHz ultrasonic miniprobe; UMP). Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone EIS. The collaterals were divided into two groups: peri‐esophageal collateral veins (peri‐ECVs) and para‐esophageal collateral veins (para‐ECVs). These were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe the peri‐ECVs group than in mild the peri‐ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, UMP findings included a significantly higher incidence of severe peri‐ECVs, a significantly larger diameter of perforating veins compared with patients without recurrence. In conclusion, the presence of severe peri‐ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these UMP abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension.  相似文献   
108.
109.
Background: The placement of an endotracheal tube (ETT) may promote laryngeal swelling, which is an important cause of upper airway obstruction after extubation. The authors hypothesized that laryngeal swelling after ETT placement increases laryngeal resistance and tested that hypothesis by comparing postoperative laryngeal patency between patients with ETT placement and those with a Laryngeal Mask Airway(TM) (LMA(TM)).

Methods: Fourteen adult patients who underwent elective minor surgeries were randomly allocated to two groups whose airway would be managed through ETTs (the ETT group) or LMAs(TM) (the LMA(TM) group) during the surgery. While maintaining at sevoflurane 1 minimum alveolar concentration, the authors measured laryngeal resistance before and after surgery, during both spontaneous breathing and mechanical ventilation under complete paralysis. In addition, they endoscopically measured the vocal cord angle under complete paralysis.

Results: In association with marked swelling of the vocal cords, the vocal cord angle significantly decreased after surgery in the ETT group, whereas the angle did not change in the LMA group. Laryngeal resistance during mechanical ventilation significantly increased only in the ETT group. Laryngeal resistance during spontaneous breathing significantly increased after surgeries in both groups.  相似文献   

110.
OBJECTIVE: Many phase II trials have shown that preoperative chemotherapy for lung cancer is feasible but associated with postoperative morbidity and mortality. However, little is known about the effect of preoperative chemotherapy on surgical stress and postoperative complications associated with surgical intervention. We evaluated the effect of preoperative chemotherapy on perioperative inflammatory cytokine production as a surgical stress marker. METHODS: The study group comprised 38 patients undergoing anatomical lung resection and mediastinal nodal dissection for clinical stage IB/II non-small cell lung cancer during the period October 2001-December 2003. Nineteen patients received a single cycle of cisplatin (80 mg/m(2)) and docetaxel (60 mg/m(2)) chemotherapy prior to surgery (neoadjuvant group), and 19 patients underwent surgery without any previous chemotherapy (control group). White blood cell and neutrophil counts and serum concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), and granulocyte colony-stimulating factor (GCSF) were determined before surgery and on postoperative days 1 and 3. Postoperative complications were reviewed. Differences were assessed by repeated analysis of variance. RESULTS: Serum concentrations of IL-6 and GCSF rose significantly on postoperative days 1 and 3 in the neoadjuvant group in comparison to concentrations in the control group, but white blood cell count, neutrophil count, and CRP did not differ between the groups. No major complication occurred in either group. CONCLUSIONS: A single cycle of cisplatin and docetaxel chemotherapy followed by surgery can exacerbate overproduction of inflammatory cytokines during the perioperative period in lung cancer patients.  相似文献   
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