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991.
杨群 《中国实用美容整形外科杂志》1996,(6)
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
992.
Dynamic imaging with lanthanide chelates in normal brain: contrast due to magnetic susceptibility effects 总被引:22,自引:0,他引:22
A Villringer B R Rosen J W Belliveau J L Ackerman R B Lauffer R B Buxton Y S Chao V J Wedeen T J Brady 《Magnetic resonance in medicine》1988,6(2):164-174
Using a one-dimensional rapid imaging technique, we have found that injection of lanthanide chelates such as Gd(DTPA)2- leads to a significant decrease (50%) in rat brain signal intensity at 1.45 T using T2-weighted pulse sequences; however, no effect of comparable size is observed with T1-weighted pulse sequences. The transient effect and its kinetics were followed with a temporal resolution of between 1 and 8 s. Experiments with different lanthanide chelates show that the observed decrease in signal intensity correlates with the magnetic moment of each agent but not with their longitudinal relaxivity. Three-dimensional chemical-shift resolved experiments demonstrate significant line broadening in brain during infusion with Dy(DTPA)2-. Our results show that the cause of this effect is the difference in susceptibility between the capillaries, containing the contrast agent, and the surrounding tissue. As a result of these susceptibility differences, field gradients are produced in the tissue and diffusion of water through these gradients leads to a loss of spin phase coherence and thus a decrease in signal intensity. We propose this as a new type of contrast agent mechanism in NMR. The effect and its kinetics are likely to be related to important physiological parameters such as cerebral blood volume and cerebral blood flow, and do not depend on a breakdown of the blood-brain barrier as do conventional contrast agent techniques. 相似文献
993.
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
994.
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
995.
(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
996.
Summary It is difficult for conventional transthoracic echocardiography (TTE), by which precise and accurate images of interatrial
septum (IAS) can not be acquired, to diagnose patent foramen ovale (PFO) clearly. To evaluate the diagnostic value of biplanar
transesophageal echocardiography (TEE) for PFO, TTE and biplanar TEE were performed simultaneously in 270 patients. It was
found that in 7 patients patent foramen ovale was detected only through longitudinal planes of biplanar TEE. IAS, which consists
of primitive septum and membrane of fossa ovalis, can be directly visualized by two-dimensional images of TEE; in patients
with PFO, a dull color flow, which shunts from the right atria to the left atria through the gap between primitive septum
and fossa ovalis, can be detected by color Doppler flow images. Furthermore, some right-to-left shunting microbubbles through
the valve of patent fossa ovalis can be discovered by cardiac acoustic contrast echocardiography. In conclusion, biplanar
TEE combined with color Doppler image and cardiac acoustic contrast facilitates a definite diagnosis of patent foramen ovale
as the excellent anatomic images of IAS can be obtained from multiple views under this kind of performance. 相似文献
997.
为探讨仅表达非系限性分化抗原的急性白血病的细胞起源,采用单克隆抗体免疫酶标和聚合酶链反应技术分析了12例初诊时仅表达非系限性分化抗原的急性白血病化疗后免疫表型及免疫球蛋白重链(IgH)和T细胞受体(TCR)γ基因重排的变化。结果表明:初诊时仅表达CD38抗原的5例急性白血病,化疗后3例出现T细胞相关抗原表达,并伴TCRγ基因重排;5例初诊时仅表达HLA-DR或CD9的急性白血病,化疗后4例出现B细胞相关抗原表达,均伴有IgH基因重排;2例无任何抗原表达者,化疗后1例表达B细胞相关抗原,另1例表达骨髓细胞相关抗原。提示免疫标志的动态研究,有助于初诊时免疫学无法分类急性白血病细胞起源的确定。 相似文献
998.
噪声对耳蜗外淋巴中某些离子含量的影响 总被引:3,自引:0,他引:3
将18只豚鼠分为1个对照组和2个暴露组,分别暴露于115dB(SPL)、125dB(SPL),1.5kHz纯音0.5h,以皮层听区诱发电位为检查指标,观察暴露前后动物听力的改变,并测定了耳蜗外淋巴中Na+、K+、Ca2+、Mg2+离子含量的变化。结果表明,声暴露后各组动物听阈明显提高,且125dB组听力损失明显高于115dB组。125dB声暴露后,耳蜗外淋巴中Ca2+明显降低,而115dB组与正常对照组相比差异无显著性。声暴露对其它离子的含量没有影响。结果提示Ca2+可能与声损伤,特别是与永久性听力损失有关。 相似文献
999.
1000.
J M Risdahl C Chao M P Murtaugh P K Peterson T W Molitor 《Pharmacology, biochemistry, and behavior》1992,43(3):799-806
Functional responses to acute and chronic morphine administration in domestic swine were examined and correlated with pharmacokinetic profiles. Acute effects of morphine sulfate were monitored in pigs for 24 h and the chronic actions of morphine alkaloid were monitored for 21 days. Serum morphine levels, nociception, locomotor activity, respiratory rate, body temperature, and body weight were monitored during all studies. To assess nociception in a large laboratory animal, a portable thermal stimulating device was constructed. Morphine sulfate administered IV and SC had a half-life of approximately 1 h whereas delayed-release morphine alkaloid delivered SC had a half-life of 28 h. The degree of antinociception paralleled decline in blood morphine levels for both SC- and IV-administered animals. Tolerance occurred to both antinociception as well as weight gain despite morphine levels remaining constant over the 21-day period. Morphine dependence was demonstrated by precipitation of an abstinence syndrome using naloxone. Animals in withdrawal displayed consistent signs, including wet-dog shakes, posture changes, vocalization, and salivation. Collectively, these results indicate that swine may be reliably employed as a model to study the actions of morphine and opiate-like compounds. 相似文献