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961.
证明春季结膜炎在穹窿结膜的临床病理。方法:详细记载球(角膜缘)、睑及穹窿结膜的临床表现;对38眼(21例)的穹窿结膜(上穹窿34眼、下穹窿4眼)进行活检,组织切片HE染色,光学显微镜下观察病理改变。结果:结膜上皮不同程度增生,上皮下淋巴细胞、浆细胞浸润或胶元纤维增生,38眼标本中32眼有嗜酸性白细胞、1眼有嗜碱性白细胞浸润。一极轻病例双眼下穹窿结膜只有很少几个淋巴细胞,其中却散在个别嗜酸性白细胞。结论:春季结膜炎的临床病理改变包括穹窿结膜。 相似文献
962.
人眼晶体悬韧带的张力测定 总被引:1,自引:0,他引:1
目的:进行人眼晶体悬韧带部位及其张力的测定。 方法:对26只离体尸眼进行测定。悬韧带的最大张力规定为:在其放松及最大伸张情况下,从睫状突到嵌入晶体前囊膜内的悬韧带的距离的差值。 结果:悬韧带在拉断之前平均能被拉长4.48±1.78mm,年轻组为5.33±1.19mm,老年组为2.17±0.70mm。无韧带区老年组为6.98±0.70mm,年轻组为7.66±0.42mm,平均为7.48±0.58mm。结论:悬韧带具有一定的张力,随着年龄的增长,悬韧带有向囊膜中心生长的趋势,无韧带区随年龄的增加而减小,悬韧带的张力随年龄的增加而减少。 相似文献
963.
人眼眩光失能测定及其临床意义 总被引:1,自引:0,他引:1
目的:观察国产仪器测定眩光失能的性能与规律,并讨论其临床意义。方法:采用MGT—1多功能视觉眩光测试仪(海军医学研究所研制),按规定方法操作。测定正常人30名56眼(矫正视力全部≥1.0,晶体透明,无其他明显眼病),晶体混浊患者15人27眼。测定目标亮度及眩光亮度设置为中—中及弱—中两档分别模拟白天及夜间眩光失能。结果:中—中状态下,眩光失能值正常人均值为9.22%(全距0~31),低于晶体混浊者(24.05%,全距9~67),两者差异显著。正常眼在弱—中状态眩光失能值较中—中状态明显(均值20.12%,全距0~56)。不同频率条件对正常及晶体混浊眼眩光失能的影响不同,低频及中频较高频区的影响明显。结论:作为视功能评论指标,眩光失能检查是一种实用方法。在眼科临床及人体工效学上具有重要的意义。 相似文献
964.
Three classical particle dissolution rate expressions are commonly used to interpret particle dissolution rate phenomena. Our analysis shows that an assumption used in the derivation of the traditional cube-root law may not be accurate under all conditions for diffusion-controlled particle dissolution. Mathematical analysis shows that the three classical particle dissolution rate expressions are approximate solutions to a general diffusion layer model. The cube-root law is most appropriate when particle size is much larger than the diffusion layer thickness, the two-thirds-root expression applies when the particle size is much smaller than the diffusion layer thickness. The square-root expression is intermediate between these two models. A general solution to the diffusion layer model for monodispersed spherical particles dissolution was derived for sink and nonsink conditions. Constant diffusion layer thickness was assumed in the derivation. Simulated dissolution data showed that the ratio between particle size and diffusion layer thickness (a0/h) is an important factor in controlling the shape of particle dissolution profiles. A new semiempirical general particle dissolution equation is also discussed which encompasses the three classical particle dissolution expressions. The success of the general equation in explaining limitations of traditional particle dissolution expressions demonstrates the usefulness of the general diffusion layer model. 相似文献
965.
Random primed polymerase chain reaction differentiates Codonopsis pilosula from different localities
DNA fingerprints distinctive among the samples from different localities in China were successfully reproduced for the Chinese herb Dangshen, the roots of CODONOPSIS PILOSULA, (Campanulaceae). Similarity index (S.I.) analysis revealed that C. PILOSULA samples from the same province generated similar DNA fingerprints, while samples of different provinces displayed different DNA fingerprints. This method may be a general and valuable tool for locality authentication of other Chinese herbal medicinal materials. 相似文献
966.
D A Nicoll-Griffith J P Falgueyret J M Silva P E Morin L Trimble C C Chan S Clas S Leger Z Wang J A Yergey D Riendeau 《Drug metabolism and disposition》1999,27(3):403-409
The lactol derivative of a lactone cyclooxygenase-2 inhibitor (DFU) was evaluated in vivo and in vitro for its potential suitability as a prodrug. DFU-lactol was found to be 10 to 20 times more soluble than DFU in a variety of aqueous vehicles. After administration of DFU-lactol at 20 mg kg-1 p.o. in rats, a Cmax of 7.5 microM DFU was reached in the plasma. After oral administration, the ED50s of DFU-lactol in the carrageenan-induced paw edema and lipopolysaccharide-induced pyresis assays in rats are comparable with the ED50s observed when dosing with DFU. Incubations of DFU-lactol with rat and human hepatocytes demonstrated that the oxidation of DFU-lactol can be mediated by liver enzymes and that a competing pathway is direct glucuronidation of the DFU-lactol hydroxyl group. Assays with subcellular fractions from rat liver indicated that most of the oxidation of DFU-lactol occurs in the cytosolic fraction and requires NAD(P)+. Human liver cytosol can also support the oxidation of DFU-lactol to DFU when NAD(P)+ is added to the incubations. Fractionation of human liver cytosolic proteins showed that at least three enzymes are capable of efficiently effecting the oxidation of DFU-lactol to DFU. Incubations with commercially available dehydrogenases suggest that alcohol and hydroxysteroid dehydrogenases are involved in this oxidative process. These data together suggest that lactols may represent useful prodrugs for lactone-containing drugs. 相似文献
967.
氟伐他汀对自发性高血压大鼠阻力血管 功能的影响 总被引:7,自引:0,他引:7
AIM: To evaluate the effects of fluvastatin, a hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitor, on the alterations of structure and function of resistant vessels in spontaneously hypertensive rats (SHR). METHODS: Eight-week-old male SHR were given fluvastatin 20 mg.kg-1.d-1 by gavage. Rats were decapitated at 16 wk. Wall-to-lumen area ratios (W/L) of thoracic aorta and mesenteric arteries (3rd grade branch) were assessed by morphometric assay. The effects of fluvastatin on vascular reactivity to sodium nitroprusside (SNP) and norepinephrine (NE), were studied with rings of thoracic aorta and mesenteric arteries isolated from rats. RESULTS: After 8 wk of treatment, histological examination showed that the wall-to-lumen area ratio was lower in SHRflu than that in SHR (0.44 +/- 0.09 vs 0.79 +/- 0.09, P < 0.05). EC50 of vasodilation response was much lower in SHRflu than that in SHR [(4.9 vs 190) pmol.L-1, P < 0.05], while EC50 of mesenteric artery rings from SHRflu was somewhat lower than that of SHR [(0.02 vs 0.04) nmol.L-1, P > 0.05]. In both aortic and mesenteric artery rings, EC50 of vasoconstriction in response to NE from SHRflu was higher than that of SHR [thoracic aorta: (0.20 vs 0.02) nmol.L-1, P < 0.05; mesentric arteries: (1.46 vs 0.72) nmol.L-1, P < 0.05]. CONCLUSION: Short-term treatment with fluvastatin ameliorated the vasomotoricity of resistant vessels, enhanced the sensitivity to vasodilator and depressed the sensitivity to vasoconstrictor; fluvastatin also attenuated the resistant vascular hypertrophy during the development of hypertension in SHR. 相似文献
968.
高效液相色谱—间接光度检测法同时测定血清和尿中5种氨基苷类抗生素 总被引:11,自引:0,他引:11
目的:建立一种直接分离测定体液中庆大霉素、丁胺卡那霉素、妥布霉素、西梭霉素和乙基西梭霉素等5种氨基苷类抗生素的高效液相色谱-间接光度检测(HPLC-IPD)法。方法:在流动相中加入具有紫外检测响应的检测剂烟酰胺,用紫外检测器直接测定紫外吸收很差的上述5种药物。C18固定相,流动相为含烟酰胺05mmol·L-1、庚烷磺酸钠5mmol·L-1和磷酸005mol·L-1的甲醇-乙腈-水(27∶18∶55)混合溶液。结果:血清和尿样平均回收率均大于96%,日内和日间RSD均小于6%。并测定了肌注此类药物病人的血清和尿样品。结论:该法适于体液中氨基苷类药物检测。 相似文献
969.
970.
Wang TK Ho SI Tsai JL Pan TM 《Zhonghua Minguo wei sheng wu ji mian yi xue za zhi = Chinese journal of microbiology and immunology》1996,29(4):210-224
From 1983 through 1993, 786 strains of Vibrio parahaemolyticus were collected from food-borne disease outbreaks and sporadic cases of diarrheal illness in northern Taiwan, involving 42 K-serotypes. Five top leading serotypes were K8 (36.8%), K15 (10.8%), K12 (8.7%), K56 (7.9%) and K63 (4.7%). However, a variation of K-serotypes was found during this study period. From 112 food-borne outbreaks associated with this microorganism, only 54 (48.2%) outbreaks were caused by a single serotype, while 58 (51.8%) were caused by multiple K-serotypes. Numbers of outbreaks caused by two, three and more than three K-serotypes were 29 (26%), 16 (14.2%), and 13 (11.6%), respectively. In a special outbreak, eight K-serotypes was found. Outbreaks caused by party caterers were most frequently associated with multiple K-serotypes. 相似文献