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991.
992.
Transient Macular Edema after Laser In-Situ Keratomileusis   总被引:8,自引:0,他引:8  
Purpose: To investigate the macular changes induced by laser in situ keratomileusisc(LASIK) procedure.Methods: Optical Coherence Tomography (OCT) was used to examine 27 eyes of 15LASIK patients before surgery, and 1 day, 1 week, 1 month after surgery.Results: The mean thick iness of neuroepithelial layer of macula was (195 ±24)microns, (178± 16) microns 1 day and 1 month after surgery, respectively, while thebaseline was (174 ± 12) microns. The increase in macular neuroepithelial thickness wascorrelated with the degree of myopia, but not with the duration of suction or thepostoperative BCVA.Conclusion: Mild macular edema is common in the first month following LASIK,especially in high myopia. However, no association with loss of BCVA has beenestablished. Eye Science 2003; 19: 20 - 24.  相似文献   
993.
急性心肌梗死患者J波的临床研究   总被引:3,自引:0,他引:3  
目的 研究心电图有 J波的急性心肌梗死 ( AMI)患者的临床情况。方法 选择住院的急性心肌梗死患者 10 2例 ,心电图有 J波者 5 0例为研究组 ,心电图无 J波者 5 2例为对照组 ,比较两组临床情况。结果 心电图有 J波组比心电图无 J波组发生胸闷 ( 3 0 /5 0∶ 2 0 /5 2 ,P<0 .0 5 )、前壁心肌梗死 ( 2 8/5 0∶ 18/5 2 ,P<0 .0 5 )、合并糖尿病 ( 14/5 0∶ 4/5 2 ,P<0 .0 5 )、超声心动图检查发生舒张功能减低 ( 2 4/5 0∶ 14/5 2 ,P<0 .0 5 )、心电图检查发现室性心动过速 ( 11/5 0∶ 1/5 1,P<0 .0 5 )者多。结论 心电图有 J波者比心电图无 J波者临床情况差 ,易于发生严重心律失常  相似文献   
994.
In 75 patients with subacute fulminant hepatitis B (SAFH), HDAg positive liver cells were observed in 14 cases (18.67%) by direct enzyme labelled method. It was found further that HDV (delta factor) infection was an important cause in producing massive necrosis of liver cells and superinfection of HDV with hepatitis B was identified as one of the causes of SAFH. This experiment also showed that the number of HDAg positive cells was in direct proportion to the area of liver necrosis. No obvious lymphocytic infiltrations and cytotoxic phenomena around the necrotic foci and HDAg positive cells could be found, while the cytoplasmic type HDAg positive cells showed distinct degeneration or even atrophy. Hence it was suggested that HDV could be a direct pathogenesis. No obvious characteristic changes in morphology of HDV infection could be found.
  相似文献   
995.
介绍两种幽门弯曲菌(CP)感染快速诊断试剂盒的制备,用其检测244例胃粘膜标本,同时与细菌培养及组织学检查结果比较。试剂盒1号、3号对诊断CP感染的敏感性分别为97%和91%,均无假阳性。CP数量、试剂盒中尿素浓度与试剂盒的反应时间呈负相关。用试剂盒3号检测在10min之内即可出结果。具有敏感性强,特异性高及简便、快速的优点,尤其适于在内镜室内使用。  相似文献   
996.
Lithium hypochlorite (LiOCl), the pool and spa sanitizer/algicide, was evaluated for genotoxicity in a battery of studies designed to evaluate potential mutagenicity, DNA damage and chromosome aberrations. LiOCl was not mutagenic in the Ames test when tested in Salmonella typhimurium strains TA98, TA100, TA1535, TA1537, TA1538 or in the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) mutation assay in Chinese hamster ovary (CHO) cells without metabolic activation. LiOCl did not induce DNA damage in the unscheduled DNA synthesis assay using rat primary hepatocytes. Effects on metaphase chromosomes were evaluated in vitro in CHO cells at 12 and 18 h exposure without S9 and at 12 and 22 h following a 2 h exposure with S9. LiOCl induced a statistically significant increase in chromosome aberrations at the high dose only at both harvest times without S9 and at the late harvest time with S9. There were significant increases in chromosome aberrations at the low dose, low-mid and high doses, but not at the high mid-dose at the early harvest time with S9. However, LiOCl did not increase chromosome aberrations when tested orally in rats at maximally tolerated doses. Bone marrow cells, collected 6, 24 and 48 h after a single oral dose of LiOCl to rats (100, 500, 1000 mg/kg in males; 50, 250, 500 mg/kg in females) showed no increase in the incidence of aberrations. In general, the weight of the evidence indicates that LiOCl is not genotoxic.  相似文献   
997.
眼袋整形术的并发症主要包括下睑外翻、下睑睫毛外翻、睑球分离、泪小点外翻、眼鼻沟畸形及眶下睑沟凹陷畸形等。皮肤眼轮匝肌及眶隔脂肪切除过多是造成上述并发症的主要原因,另外,手术中失误或操作粗糙也可造成诸如复视、泪小管撕裂甚至球后血肿等严重并发症。防止下睑外翻的发生,主要在于如何测定松弛皮肤的方法,这要把眼球活动、面部肌肉活动以及重力对面部的影响等诸因素进行综合考虑,正确估算出皮肤的切除量,才能有效防止睑外翻的发生。对于轻度外翻可采用热敷、按摩等保守治疗,对于重度睑外翻据不同情况分别采用,眼轮匝肌提紧术,睑板部分切除、结膜囊缩小术及下睑皮肤移植术加以矫正。对于眶下区凹陷及眼鼻沟畸形,术中就应注意避免,特别是要控制好眶脂的切除量,一旦发生可采用脂肪或筋膜脂肪充填,也可行眼轮匝肌提紧加以矫正。总之,在眼袋整形术中避免去除过多的组织,无论是皮肤,还是眶隔脂肪,都可有效防止并发症的发生。  相似文献   
998.
以常用的体外吸血法,对2例人工接种大量子孢子、发病后未用抗疟药治疗的间日疟现症病例,每天在发作间歇期,取静脉血感染驯化的中华按蚊,直至原虫密度下降,病程自然结束为止。结果表明,间日疟病例在临床发作的第1天对按蚊即有感染性,感染高峰见于第8病日之前,自第9病日显著下降。高感染度的持续时间极短,1例为3天,另1例为4天,分别见于发病的第4~6天和第3~6天,相当于1.5~3个无性体裂体增殖周期,以后一直维持在很低水平,且无上升趋势。由此可见,早期发现和及时治疗,在疟疾防治工作中具有重要意义;在科研工作中,凡需大量子孢子进行实验研究时,选择发作不超过3次、原虫血症较高的早期现症病例作为传染源最为适宜。  相似文献   
999.
Frictional transition of pesticides from protective clothing   总被引:1,自引:0,他引:1  
Frictional transition of pesticides, the transition of the dried pesticide due to rubbing, from protective clothing was investigated by using an AATCC standard crockmeter. One insecticide (carbaryl) and two herbicides (atrazine and metolachlor) were studied, together with three protective clothing materials [cotton, polyester, and polyester/cotton (65/35) blend] and three crock fabrics (cotton, nylon, and silk). The effects of the properties of pesticide, fabrics, water, and perspiration on the frictional transition are discussed. The experiment showed that up to 12% of the pesticide could transfer from contaminated protective clothing to the skin through rubbing. Choosing the right materials for protective clothing and underwear would greatly decrease the frictional transition of the pesticide.  相似文献   
1000.
(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine, HPMPC, and two HPMPC-related nucleoside analogs, (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine, HPMPA, and (2-phosphonylmethoxyethyl)guanine, PMEG, were evaluated for their antiviral activities against guinea pig cytomegalovirus (GPCMV) infection in guinea pig embryo (GPE) cells and human cytomegalovirus (HCMV) infection in human diploid fibroblast (MRC-5) cells. DHPG, 9-(1,3-dihydroxy-2-propoxymethyl)guanine, was used for comparison. The antiviral activity of HPMPC against GPCMV infection in vivo and its toxicity to Hartley guinea pigs were also evaluated. The 50% antiviral effective doses (ED50) of HPMPC, HPMPA, PMEG and DHPG against GPCMV infection in GPE cells were 0.22, 1.4, 0.07 and 62 microM, respectively; and against HCMV infection in MRC-5 cells, the ED50s were 0.51, 0.72, 0.01 and 17.5 microM, respectively. Their cytotoxic doses (CyD50) in GPE replicating cells were 84, 35, 1.4 and 700 microM, respectively and in MRC-5 cells were approximately 114, 31, 0.86 and 750 microM, respectively. Based on their calculated therapeutic indexes, HPMPC was the most potent and selective of the four compounds tested. In vivo, during acute infection, the spleen indexes of all infected animals that were treated with 1.25 to 5.0 mg/kg/day of HPMPC for 5 days were significantly reduced as compared with sham-treated animals. Virus infectivity titers in blood and various tissues of infected animals treated with HPMPC, 2.5 or 1.25 mg/kg/day were not significantly lower than those of the infected, sham-treated animals; with 5 mg/kg/day, infectivity titers in the blood, spleen, and salivary gland were significantly lower in HPMPC-treated than in sham-treated animals. However, HPMPC was toxic to guinea pigs especially at doses of 5 to 10 mg/kg/day. These data showed that HPMPC was highly active and selective in cultured guinea pig cells and human fibroblast cells against CMV infection but did not effectively inhibit GPCMV infection in guinea pigs at minimum toxic concentrations.  相似文献   
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