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61.
BACKGROUND: Surgical resection remains the treatment of choice for primary and secondary liver cancer. Complications are mainly related to blood loss. Radiofrequency-assisted liver resection (RF-R) has been proposed for parenchymal division as an alternative to clamp crushing in order to reduce blood loss. METHODS: Fifty patients (median age 62 (range 30-82) years) undergoing hepatectomy were randomized to RF-R (24 patients) or the clamp-crushing method (26). In the RF-R group the resection plane was precoagulated by multiple insertion of a planar triple-cooled radiofrequency ablation needle, and then the parenchyma was sectioned using a scalpel. RESULTS: The two groups were well matched in terms of age, sex, liver disease and type of resection. There were no deaths. Eight in the RF-R group developed complications (abscess in six, biliary fistula in three and biliary stenosis in one) compared with none of those who had resection by the crush method (P < 0.001). Two patients with cirrhosis in each group developed decompensation. Blood transfusion was required in eight of 24 patients in the RF-R group and 13 of 26 in the clamp-crushing group (P = 0.079). CONCLUSION: RF-R allows parenchymal resection in a clean surgical field but is associated with a higher rate of postoperative complications than the clamp-crushing technique.  相似文献   
62.
The objective of this study was to test the predictive value of serial MRI data in relation to clinical outcome for patients with glioblastoma multiforme (GBM). Sixty-four patients with newly diagnosed GBM underwent conventional MRI and diffusion-weighted and perfusion-weighted imaging postsurgery and prior to radiation/chemotherapy (pre-RT), immediately after RT (post-RT), and every 1-2 months thereafter until tumor progression, up to a maximum of 1 year. Tumor volumes and perfusion and diffusion parameters were calculated and subject to time-independent and time-dependent Cox proportional hazards models that were adjusted for age and MR scanner field strength. Larger volumes of the T2 hyperintensity lesion (T2ALL) and nonenhancing lesion (NEL) at pre-RT, as well as increased anatomic volumes at post-RT, were associated with worse overall survival (OS). Higher normalized cerebral blood volumes (nCBVs), normalized peak height (nPH) and normalized recirculation factors (nRF) at pre-RT, and nCBV at post-RT, in the T2ALL and NEL, were associated with shorter progression-free survival (PFS). From pre- to post-RT, there was a reduction in nCBV and nPH and an increase in apparent diffusion coefficient (ADC). Patients with lower nRF values at pre-RT, or a larger increase in nRF from pre-RT to post-RT, had significantly longer PFS. Time-dependent analysis showed that patterns of changes in ADC and anatomic volumes were associated with OS, while changes in nCBV, nPH, and the contrast-enhancing volume were associated with PFS. Our studies suggest that quantitative MRI variables derived from anatomic and physiological MRI provide useful information for predicting outcome in patients with GBM.  相似文献   
63.
We here report our experience in the use of locking proximal humerus plates that, compared to the old-generation ones, have shown a reduced incidence of complications, more manageability and higher preservation of soft tissues. Thirty-two patients underwent surgical treatment with plates with angular stability: 20 women and 12 men, with an average age of 52 years; in 6 cases they were fractures with 2 fragments, in 20 cases they were with 3 fragments and in 6 cases with 4 fragments. Results, evaluated according to the Constant Score, with a minimum follow-up of 6 months and the longest of 2 years, have revealed a 79-point Constant Score one year after surgery (min 42, max 94). In 2 cases we have observed necrosis of the epiphysis while there have not been any cases of secondary mobilisation of the synthesis equipment. Our findings, if we consider the low necrosis percentage, show the good adaptability and the preservation of the soft tissues as guaranteed by the synthesis equipment and by the surgery performed.  相似文献   
64.
65.

Background  

In dialysis patients, coronary angiography (CA) predicts major adverse coronary events (MACE) better than non-invasive tests. The aim of this study was to investigate in such patients the relationship between coronary atherosclerotic damage shown by angiography and MACE, during an average follow-up period of more than 5 years.  相似文献   
66.
Rectal carcinoma: CT staging with water as contrast medium   总被引:11,自引:0,他引:11  
Computed tomography (CT) was used to study 42 patients with rectal carcinoma. Water was used as a contrast medium for studying the local extent of tumor in all patients. Scans were read prospectively without knowledge of the histologic staging and then compared with pathologic specimens. CT depicted the tumor in all patients. Comparison of CT and histologic results (following the Dukes classification) showed that disease was correctly staged as A in three of four patients, as B in eight of 12, as C in 15 of 17, and as D in nine of nine. Overall, carcinoma was correctly staged with CT in 35 of 42 patients (diagnostic accuracy, 83.3%). The accuracy in the assessment of local invasion was 97.6% (41 of 42). In the detection of lymph node involvement, the accuracy was 78.6% (sensitivity, 88%; specificity, 64.7%). CT is recommended in the preoperative staging of rectal carcinoma and as an aid in choosing the appropriate therapy. The use of water enema and complete distention of the rectum are reliable techniques for improving the accuracy of CT in the assessment of local invasion by cancer.  相似文献   
67.
A series of experiments in male rabbits examined the influence of tonic immobility (animal hypnosis) on the opioid and pituitary-adrenal hormones. The aims of the experiments were to follow the temporal modifications in hormone parameters and to discriminate the effects of immobility from those of the manipulative procedure to induce the reaction. Results show that immobility elicits increases in plasma ACTH and beta-EP, but no modifications in pituitary beta-EP. The effects of induction procedure were dissociable from those of immobility, the most marked effect being a prolonged, sustained increase of corticosterone plasma levels. Results support the hypothesis of the opioid involvement in the physiological control of immobility reaction and indicate different mechanisms underlying the immobility response and the procedure of induction.  相似文献   
68.
The immune response against hapten is T‐cell‐dependent, and so requires the uptake, processing and presentation of peptides on MHC class II molecules by antigen‐presenting cells to the specific T cell. Some haptens, following conjugation to the available free amines on the surface of the carrier protein, can reduce its immunogenicity. The purpose of this study was to explore the mechanism by which this occurs. Four proteins were tested as carriers and six molecules were used as haptens. The immune response to the carrier proteins was reduced > 100‐fold by some of the haptens (termed carrier immunogenicity reducing haptens – CIRH), whereas other haptens did not influence the protein immunogenicity (carrier immunogenicity non‐reducing haptens – nCIRH). Conjugation of the protein to a CIRH affected protein degradation by lysosomal cathepsins, leading to the generation of peptides that differ in length and sequence from those derived from the same native protein or that protein modified with nCIRH. Injection of CIRH‐conjugated protein into mice induced an increase in the population of regulatory T cells. The results of this study provide a putative mechanism of action for the reduction of immune response to haptenated proteins.  相似文献   
69.
We report a fatal case of acute lower respiratory tract disease with human rhinovirus C (HRV-C) as the unique cause in a 19-month-old girl with a history of repeated episodes of bronchiolitis. HRV-C type 8 nucleic acids were observed in respiratory, stool, and cerebrospinal fluid samples, and infectious virions were isolated from patient serum after inoculation onto reconstituted airway epithelia.  相似文献   
70.
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