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31.
接触镜与泪液形态关系的临床评价 总被引:1,自引:0,他引:1
目的 :观察配戴不同种类接触镜后眼表面泪膜的形态、稳定性及泪液量的变化。方法 :对日戴SCL、RGPCL和Ortho KCL的 2 14名近视患者 4 2 8只眼 ,利用表面泪膜观察装置 (DR 1)观察戴镜前后眼表泪液膜和戴镜状态下镜上泪液膜的形态分级 ,同时测定泪膜破裂时间 (BUT)。利用酚红染色棉丝测定SCL戴镜前后的泪液量 ,并用折射仪 (AtagoCL 1)测量SCL含水量的变化。结果 :SCL配戴者随戴镜时间延长 ,BUT明显缩短 (P <0 .0 1) ,RGPCL和Ortho KCL配戴者戴镜 5年以内 ,BUT无明显变化 (P >0 .0 5 )。戴镜后RGPCL ,Ortho KCL和非戴镜正常眼三组间眼表泪膜分级比例差异无显著性 ,SCL组Ⅰ级比例为 6 .5 % ,显著低于其他组(16 .1%~ 2 3.0 % )。镜上泪膜 ,SCL、RGPCL和Ortho KCL三组均以Ⅳ级为主 (分别占 5 4 .4 %、5 3.4 %和 5 1.5 % ) ,SCLⅠ级比例仅 1.9% ,显著低于另二组 (分别占 6 .2 %和 12 .4 % )。SCL配戴者随戴镜时间延长 ,泪液量轻度减少 ,SCL含水量在戴镜 1w后即显著降低。结论 :科学配戴接触镜对泪液膜质量无明显影响 ,但SCL长期使用可能对泪膜有一定干扰作用。 相似文献
32.
33.
鼻咽癌常规放疗靶体积合理性的初步探讨 总被引:2,自引:0,他引:2
目的分析鼻咽癌常规放疗的局部控制情况和局部复发的剂量学模式,初步探讨照射靶体积确定的合理性.方法共476例初治鼻咽癌患者接受规范化单纯常规根治性放疗.全部病例均采用常规模拟定位,鼻咽靶体积为CT检查所见的原发病灶范围以及可能侵犯的亚临床病灶区域.利用Kaplan-Meier方法计算局部累积复发率;将鼻咽局部复发患者疗前和复发时局部病灶范围(Vnx和Vrecur)勾画于三维治疗计划系统,复制首程放疗的射野并按原处方剂量进行计算,根据剂量体积直方图进行剂量学评价:recurV95(95%处方剂量曲线包括的Vrecur)≥95%定义为野内复发,95%>recurV95≥20%定义为野边缘复发,20%>recurV95定义为野外复发.结果局部复发共52例,全组1、2、3、4年局部累积复发率分别为0.6%、3.9%、8.7%、11.5%.对42例局部复发的剂量学分析显示野内复发占多数(52%),而大部分野边缘复发和全部野外复发均与射野设置不当、影像学阅片能力欠缺使首程放疗剂量不足有关.结论较好的局部控制率、复发的剂量学模式的分析结果提示该靶体积的设置比较合理.提高影像阅片能力,准确的射野设计,充分利用生物影像学工具,有针对性地提高照射剂量,有望进一步提高局部控制率. 相似文献
34.
SUNG-GOO CHANG CHUL-SOO KIM SEUNG HYUN JEON YOUN-WHA KIM BO YOUL CHOI 《International journal of urology》2006,13(2):122-126
AIM: To evaluate the cause of elevated prostate-specific antigen (PSA) in patients with transrectal needle biopsy negative for prostate cancer. METHODS: Serum PSA concentration, prostate volume, and pathologic findings were examined in 223 patients with negative biopsy for prostate cancer. The degree of prostate inflammation was determined by the extent and degree of inflammation shown by biopsy specimens and is expressed as an inflammation score (range: 0-36). RESULTS: A significant correlation was found between PSA concentration and prostate total volume (P=0.0001). Prostate chronic inflammation showed no correlation with PSA concentration (P=0.485, F=0.488). After allocating patients to normal PSA (4 ng/mL) groups, we found that serum PSA concentrations in both groups were predominantly affected by prostate total volume. CONCLUSIONS: An increase in prostate volume appears to be the major contributor to a high serum PSA concentration in patients with negative biopsy for prostate cancer. However, in contrast to previous reports, there was no correlation between the degree of prostate chronic inflammation and serum PSA concentrations. 相似文献
35.
The effect of a two day fast on maternal plasma volume and plasma protein concentration was explored in pregnant rats. Fasting between days 17 and 19 of gestation prevented the rise in plasma volume observed in ad libitum fed rats. Plasma protein concentration declined between day 17 and day 19 in both fasted and not fasted rats. Placental weight was not reduced by fasting during this stage of gestation. Fetal weight in the fasted group was 91% of the fetal weight of the ad libitum fed group. These results show that acute undernutrition, like longer term food or protein restriction, can prevent adequate plasma volume expansion and slow fetal growth. 相似文献
36.
Masaki Hata Akinori Nango Hisateru Niki Yoshifumi Hayafune Atsushi Kato 《Journal of orthopaedic science》1997,2(1):3-9
To elucidate the growth of the tarsal bones in congenital clubfoot, relative to the growth of these bones in the unaffected feet and compared to growth in the feet of normal volunteers, we used a computed tomography (CT) scanner to measure the volume of all tarsal bones. The subjects of the study were 10 adults (7 men and 3 women) with unilateral congenital clubfoot (average age 20 years and 1 month). As controls, we examined 11 healthy volunteers. We calculated the ratio of the volume of each tarsal bone to the total bone volume and the ratio of the volume of each tarsal bone in clubfoot to the corresponding bone in the unaffected foot. The volume ratio of each tarsal bone was compared between clubfeet and unaffected feet because the differences of each tarsal bone ratio between the normal foot group and unaffected foot group were not significant. In the clubfeet (n=10), the talus and the medial cuneiform bones were smaller than those in the unaffected feet (n=10) but the cuboid bone was larger. The growth of the navicular did not differ from as that in unaffected feet. Our results suggested hypoplasia on the medial side of the foot in adult patients with congenital clubfoot. The 3 patients who had undergone medial release showed particularly marked hypoplasia of the medial side. In congenital clubfoot cases with severe deformities who had undergone wide soft-tissue release operations, there were clear growth suppressions in the talus and the medial cuneiform. We could not determine whether the cause of the growth suppression was the hypoplastic nature of tarsal bones themselves or the surgical obstacles to tarsal bone growth. 相似文献
37.
成人原发性肾病综合征血容量与肾素,醛固酮,心钠素的关系 总被引:2,自引:0,他引:2
探讨成人原发性肾病综合征(NS)血容量与肾素、醛固酮及心钠素的关系。方法 应用~(113)mInCl标记转铁蛋白稀释法测定血容量,放免法测定血浆激素水平。对水肿期NS28例、正常26例及其中NS缓解期随访18例进行检测。结果 (1)水肿期NS血容量与正常组无差别,血浆肾素活性(PRA)、血管紧张素Ⅱ(ATⅡ)、醛固酮(Ald)、心钠素(ANP)水平均较正常组高,白蛋白、各激素水平与血容量无显著相关;(2)缓解期与水肿期比较,总的血容量无差异,Ald、ANP显著降低,PRA、ATⅡ则无明显差异;(3)Ald与24小时尿排钠(UNaV)显著负相关。结论 Ald和ANP是NS钠排泄的主要调节因子。 相似文献
38.
Bo-Lennart Johansson Ulla Berg Ulla Freyschuss Kerstin Hall Staffan Troell 《Pediatric nephrology (Berlin, Germany)》1990,4(6):589-592
The influence of metabolic control (HbA1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients. 相似文献
39.
D. A. Haskins J. S. Jahr M.D. M. Texidor U. Ramadhyani 《Acta anaesthesiologica Scandinavica》1992,36(6):513-515
Omeprazole is a substituted benzimidazole that causes dose-dependent intracellular inhibition of gastric acid secretion in humans. This double-blind study examined the effect of omeprazole in decreasing gastric acidity and gastric residual volume in outpatient adults. Unpremedicated outpatients, ASA I-III, 18 years or older (n = 17), were randomly assigned to receive omeprazole 80 mg, or placebo by mouth the night before scheduled elective outpatient surgery. The patients were fasted for 8 h prior to surgery. After the patient was anesthetized, an orogastric tube was inserted with proper placement verified by auscultation for gastric sounds. Gastric residual contents were withdrawn into a Luken's trap, and pH was then determined and gastric volume indexed to weight (ml.kg-1). Data were analyzed by a t-test, with P less than 0.05 considered statistically significant. Patient characteristics of both groups were similar. There was a statistically significant difference between the two groups for pH (P = 0.02), but not between the two groups for gastric volume indexed to weight (P = 0.07). 相似文献
40.
J. K. Kang Sang Won Lee Min Woo Baik Byung Chul Son Yong Kil Hong Chul Ku Jung Keon Hee Ryu 《Child's nervous system》1998,14(7):297-301
Accurate assessment and replacement of blood loss and fluid–electrolyte deficit during craniosynostosis repair is difficult
owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair
over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion
practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell
mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate
if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was
used in 4 ml kg–1 h–1 except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and
EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients
(10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement
of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment
of the primary craniosynostosis.
Received: 16 February 1998 相似文献