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991.
Lovastatin, widely used to lower cholesterol, is a pro-drug that requires metabolic activation through hydrolysis by carboxyesterases. There appear to be at least three distinct esterases in humans capable of catalysing this reaction, one in plasma and two in the liver.The rate of lovastatin hydroxy acid formation was measured as 15.8 pmol · ml–1 · min–1 in plasma, 2.13 pmol · mg–1 protein · min–1 in hepatic microsomes and 0.92 pmol · mg–1 protein · min–1 in cytosol. The data suggest that on average the three esterases together are capable of activating about 220 nmol (90 g) lovastatin per minute per person, to which the esterases of plasma, liver microsomes and liver cytosol contribute approximately 18, 15 and 67%, respectively.All three esterases showed evidence of inter-individual variability. In one of 17 livers, both cytosolic and microsomal esterase activity was completely missing, while two other liver specimens lacked one esterase.Such variability must be expected to influence the therapeutic efficacy of the drug, and they might be related to its occasional toxicity. 相似文献
992.
对43例胃癌术后患者早期给予中药同时联合化疗,通过与41例同类手术后常规治疗的对照组比较,前者术后吻合口和切口的并发症均无明显增加(P<0.05),全血细胞也无明显减少(P>0.05)。同时,由于早期应用中药和营养支持,治疗组营养状况的改善明显高于对照组(P<0.05),临床研究表明,胃癌术后早期给予中药联合化疗是可行的。 相似文献
993.
A combined polymerase chain reaction (PCR) with the enzyme HaeIII restriction analysis and DNA sequencing have been employed to study the mutations at codon 249 of p53 gene in two human hepatocellular carcinoma (HCC) cell lines and 28 surgical specimens of HCC. 14 of the 28 HCC samples (50%) had p53 point mutations at codon 249. All of point mutations at codon 249 in 10 cases sequenced are AGG to AGT transversion. p53 gene mutated more frequently in invasive HCCs than that in non-invasive HCCs. This suggested that the codon 249 was a mutational hotspot of p53 gene in human HCCs in China, and p53 mutations may be related to tumor invasiveness of human HCC. 相似文献
994.
The anaesthetic management of the surgical repair of a descending aortic aneurysm in a patient with large, bilateral, pulmonary
bullae is described. Anaesthesia for descending aortic surgery normally involves unilateral, positive-pressure ventilation,
an option which poses some risk of barotrauma in the presence of bilateral bullae. Patients with bullous disease commonly
have severe lung disease and thorough preoperative assessment and preparation are necessary. Intraoperatively, bilateral rupture
of the bullae could be catastrophic and preparations should be made for this possibility. In order to diminish this risk,
a surgical technique including preemptive collapse of the bulla by minithoracotomy and tube drainage, with use of a bronchial
blocker to the affected part of the lung may be used. If rupture occurs, then high frequency jet ventilation may be effective.
Use of a double lumen endobronchial tube may be advantageous for patients with either unilateral and bilateral bullae. Anaesthesia
for patients with bullae should avoid positive-pressure ventilation and nitrous oxide in order to limit the risk of barotrauma
from a ball valve mechanism. In this case, the risk of barotrauma was reduced by performing an inhalational induction of anaesthesia
and limiting peak inflation pressures during thoracotomy. It was elected to use positivepressure ventilation through a double
lumen endobronchial tube following chest incision. A high frequency jet ventilator was available but not employed. Anaesthetic
management was complicated by the presence of pleural adhesions, surgical approach directly through a bulla, and the requirement
for one lung ventilation.
The de i’aone descendante aecouverte cnez un pattent porde grosses bulles bilatérales d’emphysème est discutée, esthésie habituelle
pour une chirurgie de l’aorte descendante site une ventilation mécanique unilatérale et constitue ainsi sque additionnel pour
le porteur de bulles emphysémas bilatérales. Ces patients ont ordinairement des affections onaires graves et l’évaluation
et la préparation préopéraprennent une importance spéciale. Pendant l’intervention, pture de bulles bilatérales peut être
catastrophique et il se préparer à cette éventualité. Pour minimiser ce risque, technique chirurgicale qui inclut le collapsus
préventif de lle par minithoracotomie et drainage, avec installation d’un ieur bronchique sur la partie atteinte du poumon.
Si une re survient, le passage à la ventilation par jet à haute tence peut être salutaire. Le tube endobronchique à double
ère peut présenter des avantages aussi bien dans les cas ulles unilatérales que bilatérales. Chez ces patients, il vaut x
s’abstenir de ventiler avec une pression positive et du xyde d’azote afin de limiter le risque de barotraumisme soupape. Dans
ce cas-ci, on a réussi à limiter le risque arotraumatisme en réalisant une induction par inhalation réduisant la pression
d’inflation de pointe pendant la cotomie. Après l’incision thoracique, on a choisi d’utiliser tilation mécanique avec un tube
endobronchique à double ère. Un ventilateur à jet à haute fréquence était prêt mais as été utilisé. La gestion de l’anesthésie
a été compliquée par dhérences pleurales, par la rencontre d’une bulle d’emphysà l’incision et par l’obligation de ventiler
un seul poumon. 相似文献
995.
The effect of surgical glove powders (Biosorb, Keoflo, and CaCO3) and Hydrocote (powder-free lubricating agent, Biogel) was examined on human skin fibroblasts and monocyte/macrophage cell lines (U937 and HL-60). Glove powders (0.1-100 micrograms/ml) in the presence of 10% fetal bovine serum (FBS) had no significant effect on the rate of 3H-thymidine uptake and proliferation of these cells after 48 h and 7 days of exposure, respectively. However, they inhibited HL-60 growth after 10 days, and Biosorb and CaCO3 inhibited U937 after 10-21 days of exposure compared with control. In the presence of low serum (0.5%), Biosorb, but not Keoflo, CaCO3, and Hydrocote, inhibited HL-60 cells after the third day of exposure (p < 0.05), whereas they were without any effect on U937 cells. Further incubation resulted in a significant decrease in cell density in all treatments, as well as controls, because of cell death. In the presence of 2% serum, glove powder-treated HL-60 significantly increased in cell numbers during the first 3 days, and the cells became stationary thereafter, whereas Keoflo and CaCO3-stimulated U937 reached a maximal by 9 days of treatment. Coculturing of fibroblasts directly with macrophages (0.4-5 x 10(5) cells per dish) or incubation with macrophage culture-conditioned media (CCM) stimulated quiescent fibroblast growth equal to that induced by 10% and 0.5% serum, respectively (p < 0.05). However, incubation of fibroblasts with glove powder-treated HL-60 CCM (except CaCO3) inhibited (p < 0.05) and CCM from Biosorb-treated U937 stimulated (p < 0.05) fibroblast proliferation. The CCM from glove powder-treated HL-60 and U937 did not have any significant effect on the rate of 3H-thymidine incorporation into fibroblasts compared with controls. The present observations suggest that glove powder action on fibroblast and macrophage growth in vitro depends on both the serum concentration of the culture medium and the length of exposure. The results imply that glove powders may have an adverse effect in vivo by directly influencing the biologic activity of macrophages, as well as other cell types, leading to alterations in the early phases of wound healing. 相似文献
996.
PreliminaryevaluationofpelvicvascularbedisolationchemotherapyinthetreatmentofadvancedcervicalcarcinomaJiangSenandPostgraduate... 相似文献
997.
此专家系统在修善顾博士行医经验和治疗原则的基础上 ,利用多媒体技术 ,结合声频、视频、图片和文本以治疗乳腺增生病。在医疗设计中 ,着重于顾博士的类型识别要点和乳腺增生病的自然规律。尤其 ,此医疗设计阐明了顾博士所总结的有价值的治疗经验 ,以突出此专家系统的科学性、实用性和可操作性。笔者曾将此专家系统应用于临床 1 30份病例的治疗中。其结果表明此专家系统的临床治疗正确率与顾博士临床治疗相对照达 98%。 相似文献
998.
AS_2O_3对消化道肿瘤细胞凋亡作用的研究 总被引:4,自引:0,他引:4
目的研究AS3O3对10种消化道肿瘤细胞株的致凋亡作用。方法采用形态学观察、流式细胞仪检测及DNA电泳分析。结果发现两株细胞经AS2O3作用后有明显凋亡,三株细胞无凋亡,其余有少量凋亡。结论AS2O3对不同的消化道肿瘤细胞有不同的作用,提示AS2O3对不同细胞的致凋亡作用可能存在不同的机理。 相似文献
999.
BACKGROUND: Three functionally distinct tryptases have been identified in the mouse, one of which encodes an unusual protease that possesses a membrane-spanning domain located in its C terminus. METHODS AND RESULTS: Using the deduced nucleotide sequence of this mouse transmembrane tryptase (mTMT) gene in a polymerase chain reaction approach, cDNAs were isolated from a number of tissues which encode its human homolog. The amino acid sequences of hTMT and mTMT are 74% identical, and the human tryptase also has the novel membrane-spanning domain. CONCLUSION: The discovery that the human genome contains a large number of homologous, but distinct, tryptase genes suggests that the individual members of this family of proteases evolved to carry out discrete functions in mast cell-mediated allergic reactions. 相似文献
1000.