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991.
非小细胞肺癌的减量性手术治疗 总被引:20,自引:0,他引:20
目的探讨非小细胞肺癌减量性手术的疗效和影响因素。方法用SPSS统计软件包的Kaplan-Meier和Cox模型,分析比较244例肺癌减量术及同期364例剖胸探查术的累积生存率和影响生存率因素。结果非小细胞肺癌减量术的1,3,5年累积生存率分别为56.9%、20.6%和17.5%;探查术为41.1%、7.8%和5.3%。两者比较,Breslow=27.55,P<0.0001。多因素分析显示,影响生存的主要因素为手术性质(减量术或探查术,B=-0.4600,P<0.0001)和有否后续治疗(B=-0.1059,P=0.0216)。结论肿瘤减量性手术是Ⅲ、Ⅳ期非小细胞肺癌的重要治疗手段之一,术后行放疗、化疗能有效地提高患者的生存率。 相似文献
992.
胃癌细胞肿瘤坏死因子受体的研究 总被引:2,自引:0,他引:2
目的 探讨人胃癌细胞肿瘤坏死因子受体 ( TNFR)的数目与胃癌细胞分化程度以及与肿瘤坏死因子突变体 ( TNF- m)细胞毒效应之间的关系。方法 以12 5I- TNF- m为配体 ,用放射配体结合分析法 ,检测了高、中、低不同分化程度的体外培养胃癌细胞 ( MKN2 8、SGC790 1、MKN4 5)的 TNFR,同时用 MTT比色法研究了 TNF- m对三株胃癌细胞的细胞毒效应。结果 三株胃癌细胞 TNFR数目分别为每细胞 9.8× 10 -12 nmol、5.6× 10 -12 nmol、3.2× 10 -12 nmol,三者之间比较 ,TNFR数目差异有显著性 ( P<0 .0 5)。解离常数基本一致 ,同一温度时三株胃癌细胞 TNF- m的内化率几乎相等 ,且呈温度依赖关系。TNFR的半衰期大约为 90分钟 ,胞膜与胞浆 TNFR数目之比约为 1∶ 2 ,TNF- m对三株胃癌细胞的最大杀伤率分别为 86%、60 %、34 % ,差异有显著性 ( P<0 .0 5) ,且 39℃时的杀伤率高于37℃时的杀伤率。结论 胃癌细胞表面 TNFR数目与胃癌分化程度相关。 TNF- m的细胞毒效应与TNF数目及 TNF- m的内化量有关。 相似文献
993.
Factor analysis, causal indicators and quality of life 总被引:1,自引:0,他引:1
Exploratory factor analysis (EFA) remains one of the standard and most widely used methods for demonstrating construct validity of new instruments. However, the model for EFA makes assumptions which may not be applicable to all quality of life (QOL) instruments, and as a consequence the results from EFA may be misleading. In particular, EFA assumes that the underlying construct of QOL (and any postulated subscales or factors) may be regarded as being reflected by the items in those factors or subscales. QOL instruments, however, frequently contain items such as diseases, symptoms or treatment side effects, which are causal indicators. These items may cause reduction in QOL for those patients experiencing them, but the reverse relationship need not apply: not all patients with a poor QOL need be experiencing the same set of symptoms. Thus a high level of a symptom item may imply that a patient's QOL is likely to be poor, but a poor level of QOL need not imply that the patient probably suffers from that symptom. This is the reverse of the common EFA model, in which it is implicitly assumed that changes in QOL and any subscales cause or are likely to be reflected by corresponding changes in all their constituent items; thus the items in EFA are called effect indicators. Furthermore, disease-related clusters of symptoms, or treatment-induced side-effects, may result in different studies finding different sets of items being highly correlated; for example, a study involving lung cancer patients receiving surgery and chemotherapy might find one set of highly correlated symptoms, whilst prostate cancer patients receiving hormone therapy would have a very different symptom correlation structure. Since EFA is based upon analyzing the correlation matrix and assuming all items to be effect indicators, it will extract factors representing consequences of the disease or treatment. These factors are likely to vary between different patient subgroups, according to the mode of treatment or the disease type and stage. Such factors contain little information about the relationship between the items and any underlying QOL constructs. Factor analysis is largely irrelevant as a method of scale validation for those QOL instruments that contain causal indicators, and should only be used with items which are effect indicators. 相似文献
994.
Kunihiko Shiraki Mitsuyasu Moriwaki Muneaki Matsumoto Takeya Khono Tokuhiko Miki 《International ophthalmology》1997,21(1):43-50
Purpose. Hypofluorescent spots were seen inindocyanine green (ICG) angiography of peau dorangefundus in eyes with angioid streaks. Origin of the hypofluorescentspots were examined with attention to their correlationwith a peau dorange appearance of the central fundususing a computer-assisted image comparison system. Methods. ICG angiography was performed in 5 patientshaving peau dorange appearance of fundus using ascanning laser ophthalmoscope (SLO) and a digitalvideo-fundus camera. The same central fundus areas corresponding to hypofluorescent spots in an ICGangiogram were then digitally identified in afluorescein angiogram and in a red-free picture in all10 eyes of the 5 patients. Monochromatic lightobservation was also performed with a dark fieldobservation using a SLO to see subretinal orintrachoroidal pigment clumping. Results. In no patient, the areas identified withhypofluorescent spots did show relevant changes ina fluorescein angiogram or a red-free picture. SLOexamination revealed not perfusion defect at the sameareas. The dark field observation showed no pigmentclumping at the peripapillary and papillomacularbundle regions where hypofluorescent spots were seen.Conclusions: Hypofluorescent spots seen in ICGangiograms did not show exact consistency with peau dorange changes in their location and shape. Perfusion defects or blocking by pigments were not acause of hypofluorescent spots. The scatteredhypofluorescent spots were considered to be relevantwith irregular affinity of the fundus to ICG dye. 相似文献
995.
Summary Pupillary test data of 103 normal and 119 diabetic subjects (47 IDDM, 72 NIDDM) were evaluated by factor analysis. From a total of nine pupillary parameters three factors were extracted in the analysis. Factor 1 represents maximal pupillary area, contraction velocity at 1 s, dilation velocity at 6 s and minimal pupillary area — static and simple dynamic parameters; factor 2 amplitude of pupillary unrest, area under the detrended curve of pupillary unrest and period of pupillary unrest — parameters of pupillary unrest; factor 3 fusion frequency of pupillary response following flicker stimuli and latency time of pupillary light reflex — second order dynamic parameters. Factor analysis was then applied to investigate diabetic patients with a high percentage of autonomic neuropathic participants (about 39 % had pupillary and about 35 % had cardio-respiratory function disorders), which revealed the same three factors as those identified in normal subjects. Furthermore, an age-related database of parameters of pupillary unrest is given. It demonstrates that normal subjects and diabetic patients did not differ in the period of pupillary unrest (normal vs diabetic (mean±SEM): 1550±29 vs 1536±27 ms; 2p>0.5). The difference in amplitude (47.8±2.8 vs 41.0±2.6 % percentile; 2p=0.071) and area under the detrended curve of pupillary unrest (47.9±2.8 vs 40.8±2.6 % percentile, 2p=0.062) seems to show a trend but was not significant. In conclusion, factor analysis revealed three different pupillary test factors. From the comparison of normal and diabetic subjects factor 1 which accounts for the highest percentage of variance (43 %) and factor 3(12 %) appear to be useful for investigating the pupillary light reflex. Factor 2 is not useful because of the insignificant differences between the normal and diabetic group. From factor analysis and partial correlation we believe that pupillary autonomic function in diabetic patients can be best assessed by using only two parameters, maximal pupillary area and latency time.Abbreviations IDDM
Insulin-dependent diabetes mellitus
- NIDDM
non-insulin-dependent diabetes mellitus
- lx
lux
- lm
lumen 相似文献
996.
A rapid method for detecting barbiturates in serum using EI-SIM 总被引:2,自引:0,他引:2
T. Kojima T. Taniguchi M. Yashiki T. Miyazaki Y. Iwasaki T. Mikami M. Ohtani 《International journal of legal medicine》1994,107(1):21-24
A simple and rapid method for analysis of barbiturates in serum has been developed. In order to extract and clean barbiturates in serum, a separation column packed with Extrelut and Florisil was used, and the eluate was directly analyzed by means of electron impact selected ion monitoring (EI-SIM). Selected ions used were base peak ions of 10 barbituartes, and the internal standard used was allobarbital or secobarbital. The calibration curves were linear over the range 0.5–5 ng. Extraction of replicate serum samples containing 20 g/1.5 ml and 5 g/1.5 ml resulted in a recovery of 87.2–105.2% and 81.6–104.6%, respectively, with the exception of phenobarbital, which was 151.9% and 172.1%, respectively. Secobarbital was also analyzed in the serum of 13 patients who had been given secobarbital intravenously. In 3 out of 10 cases, Secobarbital levels greater than 1 g/ml were detected more than 72 h after administration. This method seems to have possibilities for clinical use.Paper presented at the 2nd International Symposium ADVANCES IN LEGAL MEDICINE, Berlin, Germany, August 30–September 1, 1993 相似文献
997.
Thermal analysis of aqueous solutions in which the solute does not crystallize immediately upon freezing was carried out to define the effects of experimental parameters on thermograms in the glass transition region. The intensity of enthalpy relaxations in the glass transition region is related to both the rate of cooling and the rate of heating through the glass transition region—slow cooling or slow heating increases the extent of structural relaxation in the glassy state and increases the intensity of the endotherm. Plots of the logarithm of heating rate versus l /Tg are linear, and activation enthalpies for structural relaxation are in the range of 210–350 kJ/mol. For polymeric solutes, both the activation enthalpies for structural relaxation and the heat capacity change accompanying the glass transition increase with increasing molecular weight of the solute. Molecular weight dependence of the observed midpoint of the glass transition agrees with the Fox–Flory relationship. Results are compared and contrasted with glass transitions in solid polymers and with the glass transition of hyperquenched water. Practical implications for characterization of formulations intended for freeze-drying are discussed. 相似文献
998.
The objectives of this study were: i) to analyse the effects of morphine and naloxone on the rat's behaviour in the hot plate test using an ethological approach, and ii) to compare the effectiveness of repeated versus single test paradigms. Animals received either morphine (0, 3, 6 or 9 mg/kg SC) or naloxone (0, 0.01, 0.1 or 1 mg/kg SC). For repeated hot plate measures, rats were tested before and 60, 120, 180 and 240 min following morphine treatment, as well as 30, 60, 90 and 120 min after naloxone injection. For the single test schedule, rats were tested only once 60 min after morphine or 30 min after naloxone administration, or at 60, 120, 180, 240 and 300 min after 9 mg/kg morphine treatment. Behaviour was videotaped and analysed by an ethogram and ethological techniques. A cluster analysis revealed that the most frequently displayed patterns could be categorised into exploratory sniffing reactions (walk-sniff, immobile-sniff) and noxious-evoked elements, including primary (paw-licking, stamping), escape (jumping, leaning posture) and independent (hindleg-withdrawal) patterns. During repeated tests, morphine treatment induced: i) a maximum hypoalgesic effect 60 min post-injection (noxious-evoked patterns were significantly reduced), and ii) an unexpected thermal hyperreactivity rebound effect after 120 min (paw-licking and hindleg-withdrawal were enhanced), although changes in hindpaw-licking are more indicative of a hyperalgesic rebound effect. Most changes were quite similar during the single test schedule at 60 and 120 min after morphine injection. With regard to naloxone treatment, jumping latency was significantly decreased during the repeated test schedule, but not on single exposure to the plate. Other elements were facilitated, however, in the single test (stamping, leaning posture, hindleg-withdrawal). The results indicated that both repeated and single tests paradigms are of value for testing the effects of morphine and naloxone on rats. However, under our conditions the single test paradigm gave a better picture of the overall effects of the drug. Learning as well as habituation and sensitization may mask certain effects during repeated tests. In conclusion, an ethological analysis of the rat's behaviour in the hot plate test following administration of morphine and naloxone has been validated in this study. 相似文献
999.
M. C. Montero M. L. Valdivia E. Carvajal A. Montaño C. Buenestado A. Lluch M. Atienza 《Pharmacy World & Science》1994,16(4):187-192
This article describes the economic and social impact of nutropenia induced by myelotoxic chemotherapy in patients with cancer during the period 1 January–31 December 1991. Neutropenia is a life-threatening complication of chemotherapy in patients with cancer. The episodes of (ever and infections originating from neutropenia require hospitalization of the patient until the granulocyte levels are restored. The calculation of the economic cost was based on the following parameters: length of stay in hospital, analytical tests performed on the patient, type and cost of drug therapy administered, blood transfusions performed, health assistance received, cost of isolation and absence from work. The overall economic cost of neutropenia in patients with cancer reached 329,775 pesetas ($2,893). Cost of the health-care staff was the largest budget item in relation to the total health resources estimated. 相似文献
1000.
M. L. Swanson J. M. Collins S. F. Freiman N. H. Dubin 《Journal of assisted reproduction and genetics》1995,12(1):48-54
Purpose
This study examined sperm motion parameters as measured by computerized automated semen analysis before and after a Percoll wash and determined if differences in any parameter were correlated with fertility subsequent to intrauterine insemination (IUI).Results
Total motile sperm decreased following the washing procedure from 79.0 ± 9.0 to 37.2 ± 7.6 million sperm. Motility increased from a mean of 43.4% to 61.7% (P<0.001). Other motility parameters also changed significantly (P<0.001) as follows: curvilinear velocity (VCL), 43.4 to 61.7 m/s; straight-line velocity (VSL), 21.3 to 26.7 m/s; linearity 53.1 to 45.2%; lateral head displacement (ALH), 2.97 to 3.94 m. Similar changes occurred following a swim-up preparation, although changes in mean motility, VCL, and ALH were significantly greater when compared to Percoll. The postwash changes were not accounted for merely by time lapse in preparation since reanalyzed untreated controls did not show the same changes in motion parameters. Prewash linearity in those specimens which resulted in pregnancies was greater than in those which did not (P=0.28). No other significant differences in pre-or post-Percoll washed sperm motion parameters were found between pregnant vs nonfertile cycles.Conclusion
Following Percoll wash all CASA-generated motility parameters were significantly altered, but there was little association between these parameters and pregnancy achieved in IUI cycles.Presented at the 50th Annual Meeting of the American Fertility Society, San Antonio, Texas, November 5–10, 1994. 相似文献