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11.
Nir Lubezky Ur Metser Ravit Geva Richard Nakache Einat Shmueli Joseph M. Klausner Einat Even-Sapir Arie Figer Menahem Ben-Haim 《Journal of gastrointestinal surgery》2007,11(4):472-478
Background Recent data confirmed the importance of 18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in the selection of patients with colorectal hepatic metastases for surgery.
Neoadjuvant chemotherapy before hepatic resection in selected cases may improve outcome. The influence of chemotherapy on
the sensitivity of FDG-PET and CT in detecting liver metastases is not known.
Methods Patients were assigned to either neoadjuvant treatment or immediate hepatic resection according to resectability, risk of
recurrence, extrahepatic disease, and patient preference. Two-thirds of them underwent FDG-PET/CT before chemotherapy; all
underwent preoperative contrast-enhanced CT and FDG-PET/CT. Those without extensive extrahepatic disease underwent open exploration
and resection of all the metastases according to original imaging findings. Operative and pathological findings were compared
to imaging results.
Results Twenty-seven patients (33 lesions) underwent immediate hepatic resection (group 1), and 48 patients (122 lesions) received
preoperative neoadjuvant chemotherapy (group 2). Sensitivity of FDG-PET and CT in detecting colorectal (CR) metastases was
significantly higher in group 1 than in group 2 (FDG-PET: 93.3 vs 49%, P < 0.0001; CT: 87.5 vs 65.3, P = 0.038). CT had a higher sensitivity than FDG-PET in detecting CR metastases following neoadjuvant therapy (65.3 vs 49%,
P < 0.0001). Sensitivity of FDG-PET, but not of CT, was lower in group 2 patients whose chemotherapy included bevacizumab compared
to patients who did not receive bevacizumab (39 vs 59%, P = 0.068).
Conclusions FDG-PET/CT sensitivity is lowered by neoadjuvant chemotherapy. CT is more sensitive than FDG-PET in detecting CR metastases
following neoadjuvant therapy. Surgical decision-making requires information from multiple imaging modalities and pretreatment
findings. Baseline FDG-PET and CT before neoadjuvant therapy are mandatory.
The abstract was presented before the 58th Cancer Symposium of the Society of Surgical Oncology, Atlanta, GA, USA, 2005, and
before the 2005 Congress of the American Hepato-Pancreato-Biliary Association, Fort-Lauderdale, FL, USA. 相似文献
12.
This paper considers the immediate post‐traumatic reactions of rescue personnel who were exposed to the Hilton Hotel bombing in Sinai. The entire rescue personnel (n = 26) were assessed and separated into two groups on the basis of previous exposure to the same type of trauma. The results suggest that among rescue personnel, those with previous exposure had a lower level of post‐traumatic symptoms than those who were being exposed for the first time. This supports the hypothesis that previous exposure to the same type of trauma has an immunizing effect for subsequent same type of traumatic event among rescue personnel. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
13.
Freezing of gait affects quality of life of peoples with Parkinson's disease beyond its relationships with mobility and gait. 总被引:1,自引:0,他引:1
The aim of this study was to examine the association between freezing of gait (FOG) and quality of life (QoL) in patients with Parkinson's disease (PD). PD patients (n = 118) completed the PDQ-39 (QoL) and FOG-Q questionnaires. Disease severity was assessed by the Hoehn and Yahr (H&Y) staging and the Unified Parkinson's Disease Rating Scale (UPDRS). The relations between those parameters were assessed using regression models. 66 men and 52 women (mean age 65.8 +/- 10.2 years, UPDRS total score 48.4 +/- 17.1, disease duration 8.5 +/- 5.8 years, H&Y stage 2.7 +/- 0.8) participated. FOG severity had a significant effect on QoL (P < 0.0015), accounting for disease severity assessed by UPDRS. Specifically, FOG severity was correlated with all the dimensions of the PDQ-39 except for stigma and social support, as follows: with mobility, bodily discomfort, activity of daily living (ADL) (P < 0.005 in all), with emotional, communication, and cognition (P < 0.05 in all). FOG severity (FOG-Q) was also found to affect a modified PDQ total score, without the mobility aspect (P = 0.0081). FOG should be viewed as a highly important symptom with regard to QoL of PD patients beyond its effect on gait and mobility. On the basis of the present results, special attention should be given to FOG in the treatment of patients with PD. 相似文献
14.
Marouni MJ Barzilai A Keller N Rubinstein E Sela S 《International journal of medical microbiology : IJMM》2004,294(1):27-33
Group A streptococcus (GAS) is the principle etiologic agent of bacterial pharyngotonsillitis and a wide range of other diseases. Failure to eradicate GAS from patients has been documented in 5-30% of patients with pharyngotonsillitis, in spite of the continued sensitivity of GAS to penicillin and other beta-lactams. It was recently proposed that eradication failure might be attributed to the ability of GAS to maintain an intracellular reservoir during antibiotic treatment. We have previously shown that strains derived from patients with bacterial eradication failure, despite antibiotic treatment (persistent strains), adhered to and were internalized by cultured epithelial cells more efficiently than strains that were successfully eradicated. Since, penicillin and other beta-lactams do not penetrate well into mammalian cells, intracellular survival of GAS is crucial in order to persist during prolonged antibiotic treatment. In this study, we compared the survival of GAS strains from cases of eradication failure and eradication success, using an epithelial cell culture model. We found that persistent strains show significantly increased intracellular survival, compared to the 'eradication success' strains. This finding supports the idea that an intracellular reservoir of GAS plays a role in the etiology of antibiotic eradication failure. 相似文献
15.
Langerhans' cells were studied in the epidermis of two patients with active Behçet's disease and compared with those in two normal controls. Ultrastructural morphology and the percentage of Langerhans' cells found were similar in patients' (1.88%) and the control epidermis (1.79%). The density of Langerhans' cells in adjacent sites of the same epidermis was not homogeneous, being in the range of 0.8-2.8% in Behçet's disease and 0.6-4% in the controls. In the controls, Langerhans' cells were distributed unevenly. Some were located near the basal layer of the epidermis while the rest were in the mid and upper layers. In Behçet's disease most Langerhans' cells were in the mid-epidermis, but some were immediately beneath the stratum granulosum. In the Behçet's disease epidermis the area occupied by Langerhans' cells was increased by about 25% and the number of granules found increased by about 44%. It is suggested that in Behçet's disease the Langerhans' cells are in a more active state. 相似文献
16.
We report on a child with giant congenital aortic aneurysm, sternal defect, hemangiomas of face, supraumbilical raphé, and review the only two other cases reported to date. Congenital aortic aneurysm is an ominous malformation that has to be systematically searched in children with the sternal malformation/vascular dysplasia complex. 相似文献
17.
Michael Heming Xiaolin Li Saskia Räuber Anne K. Mausberg Anna-Lena Börsch Maike Hartlehnert Arpita Singhal I-Na Lu Michael Fleischer Fabian Szepanowski Oliver Witzke Thorsten Brenner Ulf Dittmer Nir Yosef Christoph Kleinschnitz Heinz Wiendl Mark Stettner Gerd Meyer zu Hörste 《Immunity》2021,54(1):164-175.e6
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18.
Ella Israeli Batya Raz Hedwiga Kerner David Barzilai 《Breast cancer research and treatment》1985,6(3):241-248
The levels of cyclic adenosine 3:5-monophosphate (cAMP) and cyclic guanosine 3:5-monophosphate (cGMP) were studied in dimethylbenz(a)anthracene (DMBA)-induced mammary tumors of Sprague-Dawley rats and in human breast cancer. In the rat carcinomas, these levels were significantly lower than in non-malignant tissues when calculated on the basis of DNA content, but higher (cAMP) or equal (cGMP) when calculated on the basis of weight. In human breast cancer the cyclic nucleotide levels were higher than in non-malignant tissues according to both methods of calculation. No correlation was found in human carcinomas between the cyclic nucleotide levels and mitotic index, nuclear grade, tumor size, or lymph node involvement. The rat tumors were subclassified according to state of differentiation, mitotic index, and state of development. Not all the sub-groups had cAMP levels different from normal values. Differences in cAMP levels between the sub-groups could not be correlated with tumor growth rates and/or mitotic index. Thus, cyclic nucleotides may not be useful in prognosis of breast cancer. 相似文献
19.
Although the possibility of targeting drugs to specific tissues and cells, as well as facilitating their uptake and cytoplasmic delivery has rendered liposomes a versatile drug carrier system with numerous potential applications in medicine, the molecular mechanisms of liposome-cell interactions are not understood well. Here we have reviewed the early and current concepts of liposome-cell interactions, including possible liposome receptors. Uptake of liposomes by cells can be modified by the lipid composition, particularly by the inclusion of steric stabilizers such as PEG-conjugated lipids. Such modifications also alter the circulation time and biodistribution of liposomes, which can thus be tailored for particular applications. The intracellular fate of encapsulated molecules can be modified by the use of pH-sensitive liposomes which can also be sterically stabilized. Cationic liposomes that can undergo lipid mixing with cellular membranes can deliver complexed DNA to cells, but most likely via an endocytotic process. Kinetic analysis of liposome-cell interactions can elucidate the numbers of liposome receptors of several types and the corresponding binding constants. It is likely that liposomes bind to different cell surface receptors on different cells, and that they utilize more than one type of receptor on a particular cell. The kinetic analysis also provides the rate constants of endocytosis and the percentages of liposomes that are bound or endocytosed. 相似文献
20.
BACKGROUND: Intentional selective occlusion of the arterial blood supply to tumors of abdominal organs is a well established therapeutic procedure. Several reports described gas accumulation at the infarcted sites. These gas collections are usually nonsuppurative; however, the differential diagnosis should include abscess formation. CASE REPORT: We present a 59-year-old patient in whom the splenic artery was accidentally ligated during gastrectomy surgery, with resultant splenic infarction. Gas accumulation was diagnosed by sonography and CT studies. To the best of our knowledge this is the first report ever published in the English medical literature describing nonsuppurative gas formation within an abdominal organ, caused by accidental ligation of its main arterial supply during surgery. SUMMARY: Possible theories regarding this noninfectious gas accumulation are discussed and the differential diagnosis between abscess formation and noninfectious gas accumulation is emphasized. Establishing the correct diagnosis is of big clinical importance as the treatment of choice is completely different in each one of these entities although the imaging features, in ultrasound as well as in CT, are somewhat similar. 相似文献