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1.
H. Nilsson J. Johansson K. Svanberg S. Svanberg G. Jori E. Reddi A. Segalla D. Gust A. L. Moore T. A. Moore 《British journal of cancer》1997,76(3):355-364
The biodistribution of two recently developed tumour markers, trimethylated (CP(Me)3) and trimethoxylated (CP(OMe)3) carotenoporphyrin, was investigated by means of laser-induced fluorescence (LIF) after i.v. injection into 38 tumour-bearing (MS-2 fibrosarcoma) female Balb/c mice. At 3, 24, 48 or 96 h after administration, the carotenoporphyrin fluorescence was measured in tumoral and peritumoral tissue, as well as in the abdominal, thoracic and cranial cavities. The fluorescence was induced by a nitrogen laser-pumped dye laser, emitting light at 425 nm, and analysed by a polychromator equipped with an image-intensified CCD camera. The fluorescence was evaluated at 490, 655 and 720 nm: the second and third wavelengths represent the carotenoporphyrin (CP)-related peaks, whereas the first one is close to the peak of the tissue autofluorescence. The tumour and the liver were the two tissue types showing the strongest carotenoporphyrin-related fluorescence, whereas the cerebral cortex and muscle consistently exhibited weak substance-related fluorescence. In most tissue types, the fluorescence intensities decreased over time. A few exceptions were observed, notably the liver, in which the intensity remained remarkably constant over the time period investigated. 相似文献
2.
M Vijaya Lakshmi MRCP G V Sridharan MRCP D Butterworth MRCP 《International journal of clinical practice》1993,47(3):164-165
Gallstones are common and their incidence increases with age.1 Fifty per cent of these stones are in the common bile duct (CBD) in the elderly.2 Most of them are silent but with time there is an increasing chance of developing symptoms which are more likely to be serious in the elderly.3 Failure to relieve mechanical obstruction of bile flow may lead to secondary biliary cirrhosis.4 It has been estimated that on average secondary biliary cirrhosis develops some seven years after the onset of obstruction from a stricture, four and half years after gallstone obstruction and 10 months after the onset of malignant stricture.5 The characteristic features are the pathological findings of portal-portal linkages, with a pattern of monolobular cirrhosis and the preservation of normal vascular relationships.6 Secondary biliary cirrhosis may lead to hepatic insufficiency and portal hypertension with the resultant complications, such as bleeding oesophageal varices, hypersplenism with pancytopenia, ascites and encephalopathy. We describe a patient in whom the diagnosis was not suspected until laparotomy and confirmed only at autopsy. 相似文献
3.
Zn-phthalocyanine (ZnPc) and Sn-etiopurpurin (SnET2) incorporated in unilamellar liposomes or solubilized in a Cremophor-EL emulsion have been incubated in vitro with rabbit plasma or intravenously administered to rabbits. Ultracentrifugation and chromatographic analysis of the plasma showed that ZnPc and SnET2 are mainly released to lipoproteins; within the lipoprotein family, both dyes are preferentially bound by low-density (LDL) and high-density (HDL) lipoproteins. The amount of dye bound with these two lipoprotein classes was related to their relative concentration in the plasma; in most cases a larger amount of photosensitizer was bound to HDL as compared to LDL on a protein concentration basis. 相似文献
4.
Giulio Jori 《Lasers in medical science》1990,5(2):115-120
The scope and potential of the photodynamic therapy of tumors can be enhanced through an adequate control of the factors which improve the selectivity of tumour targeting by the systemically injected photosensitizer and increase the efficiency of photosensitized tumour damage. Promising results are obtained by using hydrophobic photosensitizers which can be specifically transported and released to the tumour by serum lipoproteins, especially low-density lipoproteins. The photosensitizer molecule should possess those structural features which induce a high probability of photoactivation by 700–800 nm light, as well as a high yield of long-lived triplet state. The use of liposome-delivered Zn-phthalocyanine as a second generation phototherapeutic agent for tumours is proposed. 相似文献
5.
Treaba D Assad L Govil H Sariya D Reddy VB Kluskens L Green L Selvaggi SM Gattuso P 《Diagnostic cytopathology》2002,26(6):380-383
At the present time fine-needle aspiration (FNA) is considered a routine diagnostic procedure in evaluating neoplastic vs. nonneoplastic lesions in many organs, with high sensitivity and specificity. The purpose of this study was to assess the utility of FNA in areas of diagnostic difficulty and its limitations in evaluating bone lesions in patients with a previous history of malignancy. From 1989 to 2000, 249 CT-guided FNAs of bone lesion were performed at our institutions; 187/249 (75.1%) patients had a previous history of malignancy. Aspirated material was air-dried for Diff-Quik stain or fixed in ethanol for Papanicolaou staining. Subsequent surgical tissue was available in 69/187 (36.9%) of the cases. There were 114 males and 73 females, ages 14-86 yr (mean, 64 yr). The primary tumor site was lung 49, genitourinary 46, breast 31, gastrointestinal 28, hematopoietic 26, soft tissue/skin 5, and thyroid 2. There were 125 FNAs of the vertebral spine, 19 from the pelvis, 11 from the ribs, 9 from the sternum, 5 from the femur, and 18 from miscellaneous bone sites. Out of 187, 166 (88.7%) were malignant aspirates confirming the patients' primary malignancies. The most common malignancy encountered was adenocarcinoma, 126/187 (67.4%). Surgical tissue was available for review in 69 patients and the results were in agreement with the FNAs diagnosis in all cases. Nine out of 187 (4.8%) cases were diagnosed as marrow elements on cytological material. These patients have been followed for 1-9 yr and have failed to reveal signs or symptoms of clinical recurrence. Three out of 187 (1.6%) cases showed osteomyelitis. Nine out of 187 (4.8%) were unsatisfactory specimens, with biopsy follow-up available in four cases, showing three metastatic tumors and one case of osteomyelitis. FNA of metastatic bone lesions is a major step in pretreatment diagnosis. On satisfactory specimens, the cytological diagnosis viewed in the clinical-radiological context proves to be similar to surgical diagnosis. FNA is an excellent technique with a high accuracy rate in assessing metastatic bone lesions. 相似文献
6.
Bhattacharya B Sariya D Reddy VB Kluskens L Gould VE Gattuso P 《Diagnostic cytopathology》2002,26(6):384-386
A 4(1/2)-yr-old female presented with right-sided pleural effusion and a retroperitoneal mass. Cytologic analysis of the pleural fluid yielded malignant small round blue cells, which were noncohesive, 3-4 times the size of lymphocytes. The malignant cells had hyperchromatic, pleomorphic nuclei with moderate amounts of vacuolated cytoplasm. A few fiber-shaped cells were also seen. Immunostains for desmin, muscle-specific actin were positive; ultrastructural findings of thick and thin actin-myosin filaments confirmed the diagnosis of embryonal rhabdomyosarcoma. This case illustrates the importance of performing appropriate immunohistochemical stains and ultrastructural studies on cytological material to arrive at a definitive diagnosis. 相似文献
7.
Krishnamoorthy V Latash ML Scholz JP Zatsiorsky VM 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,152(3):281-292
Movements by a standing person are commonly associated with adjustments in the activity of postural muscles to cause a desired shift of the center of pressure (COP) and keep balance. We hypothesize that such COP shifts are controlled (stabilized) using a small set of central variables (muscle modes, M-modes), while each M-mode induces changes in the activity of a subgroup of postural muscles. The main purpose of this study has been to explore the possibility of identification of muscle synergies in a postural task using the framework of the uncontrolled manifold (UCM) hypothesis employing the following three steps in data analysis: (i) Identification of M-modes: Subjects were asked to release a load from extended arms through a pulley system, resulting in a COP shift forward prior to load release. Electromyographic (EMG) activity of eleven postural muscles on one side of the body was integrated over a 100 ms interval corresponding to the early stage of the COP shift, and subjected to a principal component (PC) analysis across multiple repetitions of each task. Three PCs were identified and associated with a push-back M-mode, a push-forward M-mode and a mixed M-mode. (ii) Calculation of the Jacobian of the system, which relates changes in the magnitude of M-modes to COP shifts using regression techniques: Subjects performed three different tasks (releasing different loads at the back, voluntarily shifting body weight forward and backward, at different speeds) to verify if the relationship between magnitudes of M-modes and COP shifts is task or direction specific. (iii) UCM analysis: Three tasks were chosen (load release in the front, arm movement forward and backward) which were associated with an early shift in COP. A manifold was identified in the M-mode space corresponding to a certain average (across trials) shift of the COP and variance per degree of freedom within the UCM (VUCM) and orthogonal (VORT) to the UCM was computed. Across subjects, VUCM was significantly higher than VORT when analysis at the third step was performed using a Jacobian computed based on a set of tasks associated with a COP shift in the same direction but not in the opposite direction. This result confirms our hypothesis that the M-modes work together as a synergy to stabilize a desired shift of the COP. Forward and backward COP shifts are associated with different synergies based on the same three M-modes.An erratum to this article can be found at 相似文献
8.
Background: Posttraumatic stress disorder (PTSD) is common in refugees but its association with longer-term psychosocial dysfunction remains unclear. We examined whether a subgroup of refugees with comorbid PTSD and depression were at particularly high risk of disability. We also investigated whether specific trauma experiences were linked to this comorbid pattern. Methods: Consecutive Bosnians (and one or two compatriots nominated by them) were recruited from a community centre, yielding a total sample of 126 participants (response rate 86%). Measures included a trauma inventory, the Clinician Administered PTSD Scale (CAPS) (Blake et al., 1995) and the depression module of the Structured Clinical Interview (SCID) (First et al., 1997). Results: Three diagnostic groupings emerged: normals (n=39), pure PTSD (n=29), and comorbid PTSD and depression (n=58). Of four trauma dimensions derived from principle components analysis (human rights violations, dispossession and eviction, life threat and traumatic loss), life threat alone was associated with pure PTSD, with life threat and traumatic loss both being associated with comorbidity. Compared to normals and those with pure PTSD, the comorbid group manifested more severe PTSD symptoms as well as higher levels of disability on all indices (global dysfunction: odds RATIO=5.0, P<0.001, distress: odds RATIO=6.0, P<0.001, social impairment: odds ratio 5.9, P<0.001, and occupational disability: odds ratio 5.0, P<0.001). Limitations: Recruitment was not random, the sample size was modest, and trauma event endorsement was based on retrospective accounts. Conclusions: The combination of life threat and traumatic loss may be particularly undermining to the psychological well-being of refugees and consequent comorbidity of PTSD and depression may be associated with longer-term psychosocial dysfunction. The findings raise the question whether the comorbid pattern identified should be given more recognition as a core posttraumatic affective disorder. 相似文献
9.
Mysorekar VV Dandekar CP Satyaprakash BS Sarkar A 《Indian journal of pathology & microbiology》2003,46(1):37-43
Endoscopic biopsies obtained from 275 patients (180 from the upper gastrointestinal tract and 95 from the lower gastrointestinal tract) were studied to compare the accuracy of biopsy imprint cytology and histology in the diagnosis of gastrointestinal lesions, and also to establish the degree of reliability of imprint cytology alone for an early diagnosis of malignancy. Biopsy histology results were found to be correct in 100% cases. Imprint cytology had an overall accuracy of 100%, 96.7%, 95.8% and 95.8% for the diagnosis of malignancies of the oesophagus, stomach, duodenum and colorectum respectively. False negative results were obtained with lymphomas. Regenerative cellular atypia was an important cause for false positive results. It was concluded that imprint cytology can serve as a useful and simple tool for an immediate diagnosis of malignancy. This should be subsequently correlated with histopathology which facilitates exact tumour typing and assessment of tumour invasion. 相似文献
10.
Fulminant hepatic failure induced oxidative stress in nonsynaptic mitochondria of cerebral cortex in rats 总被引:2,自引:0,他引:2
Fulminant hepatic failure (FHF) is a condition with sudden onset of necrosis of hepatocytes and degeneration of liver tissue without any established liver disease. FHF is associated with increased ammonia levels in blood and brain, which is supposed to be neurotoxic, ultimately leading to neuronal death. Evidences from previous studies suggest for mitochondrial dysfunctions under hyperammonemic conditions. In the present investigation, on thioacetamide-induced FHF rat models, studies were undertaken on cerebral nonsynaptic mitochondrial oxidative stress. The results of the present study reveal elevated lipid peroxidation along with reduced total thiol levels in the cerebral cortex mitochondria of experimental animals compared to saline treated control rats. In addition, the enzymatic activities of glutathione peroxidase and glutathione reductase were decreased, with an elevation in Mn-SOD activity. Overall, thioacetamide-induced FHF in rats enhanced the levels of lipid peroxidation coupled with impaired antioxidant defenses in the cerebral nonsynaptic mitochondria. 相似文献