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901.
Lipopolysaccharide-dependent and lipopolysaccharide-independent pathways of monocyte desensitisation to lipopolysaccharides 总被引:1,自引:0,他引:1
The present study demonstrates that with time in culture blood monocytes (MO) lose their ability to express procoagulant activity (PCA) and secrete tumor necrosis factor-alpha (TNF alpha) in culture medium in response to lipopolysaccharide (LPS) stimulation. Thus, upon 10 micrograms/ml LPS stimulation for 4 hours 2-day-old MO produced lower levels of PCA and TNF alpha than fresh MO. The decrease in responsiveness was not caused by cell death, since in the case of TNF alpha it was fully reversible by interferon-gamma (IFN-gamma). Compared with cells pre-incubated in medium alone, the responsiveness of MO pre-incubated in LPS was further decreased. Thus, in MO LPS pre-incubation was followed by an LPS refractory state. It was expected that the decrease in responsiveness induced by cultivation in medium alone was mediated by LPS contamination of culture medium. However, as we were unable to prevent this decrease by neutralizing LPS contamination of the culture medium with polymyxin B, the loss in LPS-induced activities of cultured MO is likely to be mediated by culture conditions other than LPS contamination. Taken together the present data demonstrate that LPS-dependent as well as LPS-independent pathways of MO desensitization to LPS exist. 相似文献
902.
J Shimizu Y Watanabe M Oda Y Hayashi T Iwa R Kamimura T Takashima 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(10):1349-1353
A case of pulmonary varices in a 73-year-old female is presented. Routine chest X-ray revealed a mass in the right hilar region. CR tomogram showed a round, clearly defined mass at the right hilum. Computed tomography demonstrated marked enlargement of the proximal portion of the pulmonary vein at the entrance of the left atrium, which was suspected to be pulmonary varices. The diagnosis was confirmed by pulmonary angiography. During the arterial phase no abnormal findings were seen, but during the venous phase the veins of the right upper and middle lobes were found to be draining into the dilated pulmonary vein and then into the left atrium. Thus, the diagnosis of pulmonary varices was established. CT and angiography are the most useful methods for definitive diagnosis of pulmonary varices. 相似文献
903.
T Terashima Y Suzuki A Kawai K Yamaguchi T Yokoyama 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(2):276-281
A 48-year-old woman was admitted because of increased bloody sputum. Since she had had a history of repeated thrombotic episodes including venous thrombosis in the lower limbs (21 year old) and pulmonary emboli developing into pulmonary infarction (41 years old), the patient was treated with anti-coagulant therapy using Warfarin for 7 years. Warfarin was discontinued after admission and heparin was administered instead at a relatively low dose of 5,000 units daily, resulting in a considerable diminution of hemoptysis. Unfortunately however, it caused a relapse of active thrombosis associated not only with a significant increase of the product of fibrinolysis (FDP), LDH and GOT but with a concomitant decrease of the platelet count. Hematological examinations concerning coagulation and fibrinolysis remained within a normal range except for the serum concentration of antithrombin III (AT III) and its functional property with regard to the heparin cofactor, which were 8.8 mg/dl and 48%, respectively. Since the findings were consistent with congenital deficiency of AT III, some members of her family were also examined. The concentration of AT III and its activity in the patient's son and her daughter deteriorated in a similar manner, indicating that this was a definite case of congenital deficiency of AT III. The clinical manifestations of 87 cases with congenital AT III deficiency, belonging to 24 families reported in Japan were reviewed. 相似文献
904.
905.
H M al-Freihi A al-Hamdan A al-Qurain Y M al-Gindan E M Ibrahim G al-Ghassab H I Nabi 《Tropical gastroenterology》1991,12(2):77-82
The efficacy and safety of a single nocturnal dose of famotidine (40 mg) was evaluated in 30 consecutive patients of duodenal ulcer (DU). Three patients were lost for follow-up and therefore were excluded. The mean age of remaining 27 patients was 34.3 (+/- 9.9) years and male to female ratio was 8:1. The mean size of the DU was 1.21 (+/- 0.79) cm. After a 4-week therapy all patients showed significant improvement and repeat endoscopy in 24 out of 27 patients (89%, 95% confidence interval; 78% to 100%) showed healed ulcer. Clinical assessment of pain relief at 4-week showed significant drop in the mean score of baseline daytime (from 1.85 to 0.13) and baseline nocturnal pain (from 1.70 to 0.10) (p less than 0.0001 and less than 0.0001, respectively). Also shown was the significant decrease in the mean gastrointestinal symptoms score from 5.89 at baseline to only 0.89 at 4-week (p less than 0.0001). Despite that all those who failed to show ulcer healing at 4-week were smokers, logistic regression analysis could not identify smoking or any other risk factors as adverse predictors of ulcer healing. None of the patients experienced significant side effects or adverse reactions. We conclude, that a single nocturnal dose of famotidine is a practical, highly effective and safe approach for the management of DU. 相似文献
906.
Replacement of cholesterol gallstones by murideoxycholyl taurine gallstones in prairie dogs fed murideoxycholic acid 总被引:1,自引:0,他引:1
B I Cohen N Ayyad E H Mosbach C K McSherry N Matoba A F Hofmann H T Ton-Nu Y Peng C D Schteingart R J Stenger 《Hepatology (Baltimore, Md.)》1991,14(1):158-168
The effect of two hydrophilic bile acids, murideoxycholic acid (3 alpha,6 beta-dihydroxy-5 beta-cholanoic acid) and ursodeoxycholic acid, on cholesterol and bile acid metabolism and hepatic pathology and gallstone composition was studied in the prairie dog. Cholesterol gallstones were induced by feeding a diet containing 1.2% cholesterol for 75 days. The animals were divided into six groups, and gallstone regression was studied as follows: groups 2 and 5, chow plus 0.2% cholesterol; groups 3 and 6, chow plus 0.2% cholesterol plus 0.15% ursodeoxycholic acid; groups 4 and 7, chow plus 0.2% cholesterol plus 0.15% murideoxycholic acid. Animals in groups 2 to 4 were killed after an additional 6 wk; animals in groups 5 to 7 were killed after an additional 12 wk. Gallstone dissolution did not occur in any group. The gallstones in groups 2, 3, 5 and 6 were typical cholesterol aggregates, as determined by polarized light microscopy and Fourier transform infrared spectrometry. The gallstones of the murideoxycholic acid group were large, solitary, dark stones that appeared radiopaque under 22 kVp x-ray examination. Scanning electron microscopy showed that in these stones the cholesterol crystals had been replaced by an amorphous material, both within the stone and on the stone surface. Chemical analysis indicated that at the end of 12 wk the calcium/sodium salt of the taurine conjugate of murideoxycholic acid (murideoxycholyl taurine) comprised 70% of the stones; protein, cholesterol and small amounts of other bile salts were also present. In vitro studies confirmed the insolubility of the sodium and calcium salts of murideoxycholyl taurine. These studies indicate that the hydrophilic bile acids, murideoxycholic acid and ursodeoxycholic acid, did not achieve gallstone dissolution under the conditions used. In the animals fed murideoxycholic acid, an insoluble calcium salt of murideoxycholyl taurine replaced cholesterol as the major constituent of gallbladder stones. This is the first example of an insoluble dihydroxy taurine-conjugated bile acid; administration of the unconjugated bile acid induced precipitation of a kind of gallstone not previously reported. The final result was transformation of cholesterol stones to bile salt stones. 相似文献
907.
重组人表皮生长因子对促进Ⅱ度烧伤愈合的作用 总被引:5,自引:0,他引:5
目的 探讨重组人表皮生长因子(rhEGF)对促进Ⅱ度烧伤创面愈合的作用。方法 采用自身对照研究方法,选取46例Ⅱ度烧伤患者观察最适治疗浓度创面局部应用的治疗效果及不良反应。结果 在浅Ⅱ度烧伤创面,观察组的愈合时间为(8.7±2.1)天,对照组为(12.2±2.4)天,而深Ⅱ度烧伤创面观察组的愈合时间是(13.4±2.6)天,对照组为(19.2±3.2)天。与对照组相比,观察组创面愈合时间均有明显缩短(P<0.01),结论 rhEGF对Ⅱ度烧伤创面均可有效地促进组织修复,加快创面愈合速度,有良好的促进愈合作用,而药物反应极轻微。 相似文献
908.
X F Sun H Zhang X C Wu Y M Han G Q Hou M S Xian 《Acta oncologica (Stockholm, Sweden)》1992,31(1):37-40
The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development. 相似文献
909.
910.
Y Muraki T Kobayashi H Kojima A Shibuya T Nagasawa T Abe N Mori 《[Rinshō ketsueki] The Japanese journal of clinical hematology》1992,33(3):328-332
A 50-year-old woman with anorexia nervosa was admitted for evaluation of neutropenia (WBC 1,600/microliters). Her bone marrow was gelatinous, and myeloid cells had decreased. Homogeneous substance deposited in the marrow, stained by alcian blue (pH 2.5), indicative of acid mucopolysaccharides. CFU-G and CFU-GM were decreased in number and myeloid pool in the bone marrow also decreased. Anti-neutrophilic antibody was negative. Neutropenia may be related to myeloid hypoplasia, due to increase of acid mucopolysaccharides replacing adipose cells in the bone marrow under long-term mal-nutritional state. Neutrophils markedly increased by administration of rhG-CSF 5.0 micrograms/kg/day for 14 days without the first peak. Serum G-CSF level did not increase (less than 60 pg/ml). It is effective to administer G-CSF to anorexia nervosa with neutropenia. 相似文献