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1.
We examined clinicopathologic findings in 86 cases with peripheral lung nodules less than 30 mm in size diagnosed by open lung or video-assisted thoracoscopic surgery (VATS) biopsy. Biopsies were conducted because of the new appearance or enlargement of nodules as evidenced in a comparison with retrospective chest films in 47 patients, X-ray findings of malignancy suspicion without retrospective films in 13, enlargement of nodules after the administration of antituberculosis agents in 9, and a past history of malignancy in 17. Mean tumor size was 18.1 mm in primary lung cancer (n = 29), 16.2 mm in metastatic lung cancer (n = 13), 16.3 mm in tuberculosis (n = 18), 15.3 mm in nonspecific inflammation (n = 12), 16.7 mm in benign lung tumors (n = 7), 7.5 mm in intrapulmonary lymph node (n = 2), and 19.4 mm in others (n = 5). Among primary lung cancers with a clear N-factor, the percentage of T1N0M0 cancers was up to 72%. No significant difference was observed in either of the reasons for these biopsies and the size of nodules among diseases. To detect early lung cancer and increase the rate of cure, small pulmonary nodules that could be hardly diagnosed using bronchoscopic or needle aspiration biopsy should be diagnosed positively using VATS biopsy.  相似文献   

2.
The physical and imaging characteristics of a number of commercially available rare earth screen/film combinations were evaluated and compared to those of conventional calcium tungstate/X-Omat RP-14 systems. All systems were evaluated for base-plus-fog density, relative speed, resolution, noise, and overall performance. The results indicate that despite certain limitations, rare earth screen/film combinations offer significant advantages for imaging.  相似文献   

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Mouse peritoneal macrophages were incubated in DMEM medium with batroxobin (DF-521) to determine the effect of batroxobin on the internalization of peroxidized low-density lipoprotein (pox-LDL) by transmission electron microscopy. Although the morphology of the mouse peritoneal macrophages after incubation with DMEM, normal LDL (n-LDL) and n-LDL plus batroxobin was similar to that of the cells before incubation, they exhibited numerous cytoplasmic lipid droplets after incubation with pox-LDL for 4 h. After addition of batroxobin to the medium containing pox-LDL, the production of lipid droplets in the mouse peritoneal macrophages was tremendously accelerated. Batroxobin accelerates the phagocytosis and degradation of pox-LDL by macrophages.  相似文献   

5.
This study was undertaken to investigate the use of maximum intensity projection (MIP) images in the detection of pulmonary nodules by spiral CT (SCT). 40 pulmonary nodules of high density were created by endobronchial deployment of 2 and 4 mm beads in the peripheral airways of five anesthetized dogs. Standard SCT was performed with 5 mm collimation, pitch 2 and reconstruction of contiguous slices. MIP images were generated from overlapped slabs of seven consecutive 3 mm slices, reconstructed at 2 mm intervals and acquired at pitch 2. Scans were reviewed by six radiologists. The data were modelled using ordinal logistic regression for repeated measures, and the Wald chi 2 statistic used to test if there was a difference in nodule detection and reader confidence level between the two techniques. MIP imaging increased the odds of nodule detection by 2.18 (p = 0.0002). Reader confidence level for nodule detection was significantly higher with MIP images (p < 0.00001). MIP images improve the detection rate for small high density pulmonary nodules and increase reader confidence level, when compared with standard SCT.  相似文献   

6.
OBJECTIVES: Uncontrolled data often have to be used in clinical decision marking and in the planning of clinical trials. When such data are used as a basis for comparing different treatment strategies, they tend to generate sources of bias such as inconsistent patient selection, misrepresentation, and measurement errors. A rational usage of uncontrolled data requires identification and handling of different systematic errors when comparing different treatment strategies. Therefore we sought to define a systematic error that deserves more attention in the clinical literature. METHODS: Using hypothetical examples, we illustrate the bias introduced by variations in "lead time," proportions of so-called prevalent/incident cases, and lengths of follow-up between reference and treatment groups. RESULTS: We found these three situations conceptually identical. Bias is introduced because different parts of a nonconstant hazard curve over time are observed. CONCLUSIONS: The systematic error described is potentially important in uncontrolled data provided the hazard rate over time is nonconstant. Thus the seemingly worse outcome after external beam radiation therapy as compared to the outcomes of deferred treatment of radical prostatectomy in compiled patient series of localized prostate cancer may in some part be explained by bias due to observation of different parts of a nonconstant hazard curve over time.  相似文献   

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Familial hypothalamic diabetes insipidus is an autosomal dominant disorder characterized by deficient vasopressin synthesis. Different point mutations in the vasopressin-neurophysin (VP-NP) precursor gene have been found in affected families. In a Dutch kindred, a single G to T transversion in the NP-encoding exon B of one allele converts the highly conserved glycine 17 to a valine residue. In order to examine whether this point mutation affects the processing and transport of the VP-NP precursor, the normal (HV2) and mutant (MT6) vasopressin cDNAs were stably expressed in the mouse pituitary cell line AtT20. The normal precursor was correctly glycosylated and processed, and NP was detected in the culture medium. Secretion of NP was stimulated by 8-bromo-cAMP, indicating that the normal precursor was targeted to the regulated secretory pathway. In contrast, the mutant precursor was synthesized, but processing and secretion were dramatically reduced. The mutant precursor was core-glycosylated but remained endoglycosidase H-sensitive, suggesting that the protein did not reach the trans-Golgi network. These results were supported by immunocytochemical studies. In HV2 cells, NP derived from the precursor was concentrated in the tips of the cell processes where secretory granules accumulate. In MT6 cells, NP staining was restricted to the endoplasmic reticulum (ER) as determined by colocalization with an ER-resident protein, BiP. These results suggest that the mutation within the conserved part of NP alters the conformation of the precursor and thus triggers its retention in the ER.  相似文献   

9.
The purpose of the present study was to elucidate the characteristic lipoprotein disorder in essential hypertension. Twenty-six patients with essential hypertension (HT) but without diabetes mellitus or obesity and 24 healthy subjects (control) were recruited into this study. Lipoproteins of HT and controls were separated by ultracentrifugation to very-low-density lipoprotein (VLDL), intermediate density lipoprotein (IDL), low-density liproprotein (LDL), and (HDL) fractions. Cholesterol and triglycerides were determined with enzyme assay, and apoB were determined by highly sensitive latex agglutination (Kyowa-hakko Co. LD). There was no difference in age (mean +/- SE; HT, 63 +/- 2 versus control, 60 +/- 2 years) or body-mass index (22.7 +/- 0.4 versus 21.7 +/- 0.5 kg/m2) between HT and controls. Blood pressure in HT and controls was 158 +/- 2/87 +/- 12 mm Hg and 123 +/- 3/72 +/- 2 mm Hg, respectively. Cholesterol did not change significantly in plasma (192.1 +/- 7.0 versus 176.4 +/- 4.2 mg/dL), VLDL (15.2 +/- 2.4 versus 11.8 +/- 1.7 mg/dL), IDL (14.8 +/- 2.4 versus 10.7 +/- 1.6 mg/dL), LDL (93.7 +/- 4.6 versus 83.1 +/- 3.9 mg/dL), nor in HDL (51.9 +/- 2.7 versus 58.1 +/- 3.2 mg/dL). Triglycerides (TG) increased in plasma (120.0 +/- 10.0 versus 87.5 +/- 9.3 mg/dL, p < 0.05), although TG did not change in all subfractions. ApoB increased in plasma (105.5 +/- 5.1 versus 85.6 +/- 3.6 mg/dL, p < 0.01), IDL (9.0 +/- 1.3 versus 5.4 +/- 0.6 mg/dL, p < 0.05), and LDL (76.3 +/- 4.3 versus 59.4 +/- 3.7 mg/dL, p < 0.01) in HT compared with controls. The ratio of cholesterol to apoB in LDL decreased (1.27 +/- 0.06 versus 1.48 +/- 0.08, p < 0.05). In essential HT, number of apoB containing lipoproteins (IDL, LDL) increased. Low ratio of cholesterol to apoB was noted in LDL, indicating the presence of small, dense LDL. As cholesterol in LDL was normal, hyperbetalipoproteinemia is also a characteristic disorder of essential HT.  相似文献   

10.
The purpose of this study was to investigate the accuracy of ultrasound speckle tracking in various tissues. Results from two-dimensional tissue speckle tracking in liver, muscle, fat, and sponge samples are presented, while keeping other speckle tracking parameters constant. Speckle tracking performance was characterized both in terms of the magnitude of tracking errors and in terms of the percentage of correctly tracked displacement vectors. Speckle tracking in muscle tissue, which contains myofibrils and significant tissue microstructure, produced the highest percentage of correctly tracked vectors and smallest tracking errors relative to other tissues.  相似文献   

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The experimental conditions for detection of segregated elements in the X-ray spectrum recorded from small precipitates ≦ 100 nm diameter contained within a thin foil of an iron base alloy using STEM-EDS X-ray microanalysis are described. The influence of precipitate size, position and composition, foil thickness, electron accelerating voltage, and X-ray emission intensity on its detectability are evaluated. Optimum experimental conditions for microanalysis of these precipitates are established and the limitations of current techniques discussed.  相似文献   

13.
OBJECTIVE: We analyzed our experience in the period January 1975-December 1995 aiming to confirm the role of surgery in the multimodality treatment of small cell lung cancer (SCLC). METHODS: 127 patients (5.28% of the overall lung resections for carcinoma) underwent surgery for SCLC. The median age was 60 years (range 34-73). In 87 patients (68.5%) a pre-operative tissue diagnosis was effected and those patients underwent a complete staging procedure. Fifteen patients received up to six complete courses of neoadjuvant and adjuvant chemotherapy. The surgical procedures included: 50 pneumonectomies, 71 lobectomies and six wedge resections. Two patients experienced a local recurrence and a completion pneumonectomy was performed. RESULTS: The median follow-up is 66 months (range 6-214). The 5-year actuarial survival rate is 22.6% (median 18 months). Twenty-three patients are still alive, 21 of them being disease-free. Considering the most conspicuous group of patients (n = 92) treated by surgery and adjuvant chemotherapy, the survival data were 47.2, 14.8 and 14.4% for Stage I, II and III, respectively (P = 0.001). NO patients had a significantly better survival than N1 and N2 patients (P = 0.035). CONCLUSIONS: Surgery and adjuvant chemotherapy might represent an effective form of treatment of limited SCLC without lymph-node involvement. The role of surgery is yet to be verified as regards N1 and N2 status, where even neoadjuvant chemotherapy has not achieved the hoped-for results (no patient reaching a 2-year survival).  相似文献   

14.
We performed genetic analysis on 12 second primary non-small cell lung cancers in patients surviving small cell lung cancer to assess the potential contribution of smoking to the development of these tumors. Mutations of TP53 were found in three (25%) tumors, KRAS2 in three (25%) tumors, and CDKN2 in two (18%) tumors. Four (50%) mutations (one each in TP53 and CDKN2 and two in KRAS2) were G:C to T:A transversions on the coding strand, a mutation accounting for approximately one-third of mutations in smoking-related tumors but uncommonly found in lung cancers not associated with smoking. The genetic changes in these second lung cancers are more representative of smoking-associated malignancies than lung cancers arising in patients occupationally exposed to irradiation and atomic bomb survivors.  相似文献   

15.
X射线荧光光谱分析多矿源铁矿石中9种成分   总被引:2,自引:2,他引:2       下载免费PDF全文
铁矿石样品与Li2B4O7、Li2CO3熔剂按比例混合并定量加入钴内标元素(mLi2B4O7∶mLi2CO3∶mCo2O3∶m试样=6∶1∶1∶0.7),采用电加热熔融法制备熔片,以X射线荧光光谱法测定铁矿石中TFe,SiO2,CaO,MgO,TiO2,MnO,Al2O3,P,S 9种成分的含量。根据铁矿石中被测成分的含量范围,选取具有含量梯度的铁矿石标准样品,并加入经过化学法准确定值的生产样品,采用内标法,绘制校准曲线。以仪器提供的基体校正方法消除吸收与增强效应影响。方法用于多矿源铁矿石标准样品的分析,测定结果与认定值相一致,相对标准偏差(n=7)为0.10%~8.1%,满足铁矿石的检测需求。  相似文献   

16.
镀锡钢板铬酸盐钝化膜中铬的X射线光电子能谱分析   总被引:2,自引:0,他引:2       下载免费PDF全文
使用X射线光电子能谱(XPS)分析方法,对镀锡铬酸盐钝化钢板中铬元素的含量、价态以及不同价态化合物的含量进行了研究,并对镀锡钢板铬酸盐钝化膜的形成机理进行了探讨。结果表明,钝化膜中主要含有Cr,O以及Sn元素。在给定的钝化处理工艺条件下,镀锡铬酸盐钝化钢板中铬元素主要是以Cr(OH)3,Cr单质以及Cr2O3的形态存在,在检测中没有发现六价铬离子。铬酸盐钝化膜中Cr,Cr2O3和Cr(OH)3的质量分数分别是2.0%,9.5%,7.5%。  相似文献   

17.
OBJECTIVE: To compare film for intra-oral radiography with two charge-coupled device (CCD) and one storage phosphor system for digital imaging in respect of subjective image quality, detectability of small mass differences and appearance of burn-out effects and blooming phenomena at various exposure times. METHODS: Dried mandibles with teeth from different areas were radiographed at exposures covering a relative range from 1 to 100. Image quality was subjectively evaluated after image processing, when applicable, using a visual grading scale from 0 to 10. The number of visible holes in an aluminium block was used to measure the detectability of small mass differences. Burn-out effects and blooming were evaluated by measuring widths of roots and of aluminium and plastic cylinders. RESULTS: Radiographs with the storage phosphor system achieved image quality scores similar to those of film but over a larger exposure range, while CCD images were rated lower and over a smaller range. All holes in the aluminium block were only detected with the storage phosphor system. While the widths of roots were strongly affected by sensor saturation in CCD images and by burn-out in film images, smaller effects were seen with the storage phosphor system. Similar results were obtained with aluminium and plastic cylinders. CONCLUSIONS: Higher image quality was achieved over a much wider exposure range with the storage phosphor system than with either film or the CCD systems.  相似文献   

18.
A monoclonal antibody (mAb) binding to protein C (PC) heavy chain but not to activated PC was found to inhibit PC activation by free thrombin, suggesting that epitope involved the activation site. Using a set of overlapping synthetic peptides, we confirmed that this mAb recognizes the sequence encompassing the thrombin cleavage site (165QVDPRLI(171)). Surprisingly, epitope was only accessible in the absence of calcium, half-maximal inhibition of mAb binding occurring at 100 microM Ca2+. Thus, our antibody provides direct evidence that conformation and/or accessibility of the activation site differ between the apo and Ca2+-stabilized conformers of PC.  相似文献   

19.
HSL from chicken adipose tissue exhibits remarkable activation upon phosphorylation with cAMP-dependent protein kinase (cAMP-PK) compared to HSL from rat and human adipose tissue. In order to characterize the chicken HSL enzyme, it was purified 3500 fold from a chicken adipose tissue homogenate using pH 5.2 precipitation and anion-exchange chromatography. The purified chicken HSL was identified as an 86 kDa protein using Western blot analysis. The HSL diacylglycerol lipase activity was inhibited by 98% upon incubation with anti-rat HSL antiserum, and the specific activity of chicken HSL was estimated to be approximately the same as for the rat enzyme. Furthermore, the 86 kDa polypeptide was phosphorylated by cAMP-PK to about the same stoichiometry as for the recombinant rat enzyme. Hence, our results demonstrate that HSL from chicken adipose tissue is comparable in size and specific activity to HSL from mammalian species, and not a smaller 42 kDa polypeptide with 1000-fold lower specific activity as previously reported (Berglund, L., Khoo, J. C., Jensen, D., and Steinberg, D., 1980 J. Biol. Chem. 255, 5420-5428).  相似文献   

20.
Creativity in movies is a topic of growing interest in both the psychological and the marketing literature. Much research has been invested into determining the impact of cinematic quality on film success and finding successful predictors of cinematic creativity. For these reasons, research into the way creativity is measured in film is of considerable importance. This study examines a variety of measures of cinematic quality (movie ratings from a variety of sources) and determines the degree of agreement among different types of measures, the predictive value of these measures, and the effect of the timing of these measures on their predictive value. Results indicate that there is a high degree of agreement among types of movie ratings, that reviews through release day tend to be marginally higher than those that appear later, and that reviews are more highly correlated with later box office success (gross) than with early box office success. A surprising result of this study was that the number of ratings a movie received was a slightly better predictor of box office success than the actual movie ratings. Possible explanations for and implications of these results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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