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131.
The extended survival of patients with Duchenne muscular dystrophy (DMD) achieved by the introduction of mechanical ventilation is raising new quality-of-life issues. We evaluated passive range of wrist extension, key pinch strength, and power wheelchair driving in 84 patients. The 47 drivers with restricted driving abilities were older than the 37 unrestricted drivers (27.2+/-5.0 y vs. 22.8+/-3.8 y) and had worse upper limb performance. By multiple logistic regression, only key pinch was significant ( R(2) = 0.224, P = 0.02. Eighteen restricted drivers were reassessed after having swapped a conventional joystick for another control system (mini-joystick, isometric mini-joystick, finger joystick, or pad) and having moved the position of the tested control system so that the patient could use it with different fingers, his chin or his mouth. All of them regained the ability to drive unrestricted. Adults with DMD gradually lose their ability to drive with a conventional joystick but can regain unrestricted driving with alternative control systems.  相似文献   
132.
PURPOSE: To confirm the diagnostic accuracy of percutaneous core breast biopsy with Mammotome and stereotactic equipment in upright seated patients, and to compare results from this method with those obtained using the dedicated unit with prone table. MATERIALS AND METHODS: We analysed 72 microbioptic samples from 69 upright seated patients. These samples were obtained in the course of mammographies assisted by digital stereotactic equipment (Diamond Delta32 General Electric Medical System/Instrumen-tarium), and further equipped with a lateral arm to support the Mammotone probe. We studied the following lesions: 57 cases of isolated microcalcification clusters, 12 masses with microcalcification and three cases of plain masses. We describe in detail the various phases of our 30-minute long microbiopsy procedure. All 72 samples were extracted without problems. Only in one case a large haematoma emerged, but quickly disappeared. RESULTS: We were able to characterise the histology of the lesions in all our samples: in 39/72 cases they were identified as benign, 28 were classified as malignant, and the remaining 5 as atypia. In the 39 lesions identified as benign, the microbiopsy procedure could be carried out without surgical biopsy - consequently, these patients were available for routine follow-up exams, which confirmed the benign nature of their lesions. Our identification of the 28 malignant lesions was confirmed by surgical biopsy. The microbiopsy finding and the histological result did not agree in only two cases. The 5 cases with atypical ductal hyperplasia showed no neoplastic alteration following surgical biopsy. In our personal experience, core biopsy with Mammotome achieved a high diagnostic accuracy. CONCLUSIONS: After careful analysis of the results obtained using Mammotome in upright seated patients with stereotactic equipment, we can confirm the diagnostic accuracy of this procedure in mammography alterations not visible in sonography. In agreement with previous studies, we also confirm that the diagnostic accuracy of this approach, as well as possible complications deriving from it, do not depend on the position of the patient.  相似文献   
133.
Rationale 3,4-Methylenedioxymethamphetamine (MDMA) is an amphetamine derivative, which is neurotoxic to both serotonin (5HT) and dopamine (DA) nerve terminals. Previous reports, carried out in rodents and non-human primates, demonstrated neurotoxicity to monoamine axon terminals, although no study has analyzed nigral and striatal cell bodies at the sub-cellular level.Objective In this study, we examined intrinsic nigral and striatal cells, and PC12 cell cultures to evaluate whether, in mice, MDMA might affect nigral and striatal cell bodies.Methods After administering MDMA, we analyzed effects induced in vivo and in vitro using high-performance liquid chromatography (HPLC) analysis, light- and electron microscopy with immunocytochemistry, and DNA comet assay.Results We found that MDMA (5 mg/kg ×4, 2 h apart), besides a decrease of nigrostriatal DA innervation and 5HT loss, produces neuronal inclusions within nigral and intrinsic striatal neurons consisting of multi-layer ubiquitin-positive whorls extending to the nucleus of the cell. These fine morphological changes are associated with clustering of heat shock protein (HSP)-70 in the nucleus, very close to chromatin filaments. In the same experimental conditions, we could detect oxidation of DNA bases followed by DNA damage. The nature of inclusions was further investigated using PC12 cell cultures.Conclusions The present findings lead to re-consideration of the neurotoxic consequences of MDMA administration. In fact, occurrence of ubiquitin-positive neuronal inclusions and DNA damage both in nigral and striatal cells sheds new light into the fine alterations induced by MDMA, also suggesting the involvement of nuclear and cytoplasmic components of the ubiquitin-proteasome pathway in MDMA toxicity.  相似文献   
134.
Pinhole gamma camera imaging offers the ability to obtain high resolution images from single gamma ray emitting radiotracers playing a reasonable tradeoff between very small field of view (FoV) and sensitivity. On the other hand the total spatial resolution of a pinhole imaging device is predominantly affected by the detector intrinsic spatial resolution for reduced magnification factors. To design very compact pinhole SPET scanners with very high intrinsic spatial resolution, authors investigated a miniature gamma camera based on the newly developed Hamamatsu H8500 flat panel photomultiplier. The PSPMT was coupled to the following scintillation arrays: CsI(Tl) array with 0.2-mm, 1-mm, 1.4-mm pixel size and NaI (Tl) with 1-mm pixel size. The imaging performances were evaluated by 57Co spot and flood irradiations. NaI(Tl) array shows a better pixel identification for 1 mm pixel size, proving to be a good candidate to make a large area photodetector based on multi PSPMTs closely packed. Although CsI(Tl) array had the smallest pixel size, the low light output limited the best intrinsic spatial resolution to about 0.5 mm.  相似文献   
135.
AIM: To evaluate the main factors associated with mortality in patients undergoing surgery for perforated peptic ulcer referred to an academic department of general surgery in a large southern Italian city. METHODS: One hundred and forty-nine consecutive patients (M:F ratio=110:39, mean age 52 yrs, range 16-95) with peptic ulcer disease were investigated for clinical history (including age, sex, previous history of peptic ulcer, associated diseases, delayed abdominal surgery, ulcer site, operation type, shock on admission, postoperative general complications, and intra-abdominal and/or wound infections), serum analyses and radiological findings. RESULTS: The overall mortality rate was 4.0%. Among all factors, an age above 65 years, one or more associated diseases, delayed abdominal surgery, shock on admission, postoperative abdominal complications and/or wound infections, were significantly associated (chi2) with increased mortality in patients undergoing surgery (0.0001相似文献   
136.
Jehovah's Witnesses, patients who refuse blood transfusions, are generally not considered as candidates for lung transplantation owing to the frequent requirement for transfusions. A successful procedure in a Jehovah's Witness is presented and to our knowledge this is the 2(nd) reported case. The patient, a 38-year-old female, type I diabetes, affected by idiopatic pulmonary fibrosis underwent left lung transplantation. From the same pulmonary bloc a twinning procedure was obtained by means of right lung transplantation in a 58-year-old man affected by the same pathology. Surgical strategies employed in achieving a successful outcome, ethical and moral aspects are discussed.  相似文献   
137.
138.
Abstract. The present study explores whether effects induced by amphetamine derivatives on striatal GABA cells might be connected with effects on dopamine (DA) metabolism. Methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) were administered to C57Black mice following a dosage regimen in which various doses of both drugs were injected i.p. at 2-h intervals. Neuronal inclusions produced under these experimental conditions were examined under electron microscopy. Drugs reducing DA availability prevented inclusion formation; conversely we observed that increasing DA synthesis or impairing physiological DA degradation enhanced the number of inclusions. The present study indicates that the presence of extracellular striatal DA is essential for the production of subcellular alterations induced by amphetamine derivatives. This is in line with a recent hypothesis connecting striatal DA release with degeneration of striatal GABA neurons.  相似文献   
139.
The occurrence of pulmonary gas embolism in patients undergoing laparoscopic cholecystectomy is reported in the medical literature. Severe intraoperative complications or the patient's death were correlated to gas embolism during laparoscopic procedures. However, the careful retrospective study or the autoptic exam of such casualties have always showed an erroneus direct puncture of vessels or the straight insertion of the Veress needle into a parenchymal organ. It is obvious that the direct gas injection into a vein or into parenchymal organs is a primary cause of gas embolism, as well as the high flow insufflation of gas into the peritoneal cavity in concomitance with the lesion of major abdominal vessel's wall. Gas embolism may occur each time the vein internal pressure is lower than the external pressure and not only during a laparoscopic procedure when carbon dioxyde is inflated into the peritoneal cavity, but also during open surgery such as major liver resections, neurosurgery, vascular or cardiac surgery. The review of large series of laparoscopic cholecystectomies reported in the international literature, as well as our own clinical experience in this field, together with the results of laboratory animal studies based on the experimental insufflation or injection of carbon dioxyde, show that gas embolism must not be considered as a complication of laparoscopic surgery. Due to the above mentioned risks with the use of the Veress needle, the surgeon should revalue alternative means in creating the pneumoperitoneum.  相似文献   
140.
Cancer vaccines directed against tumor associate antigen (TAA) have produced encouraging results in preclinical models but not in cancer patients. A major limitation of this strategy is the relative degree of tolerance to these antigens and the low and heterogeneous tumor cell expression of TAA and major histocompatibility complex (MHC). Previous studies have shown that 5-fluorouracil (5-FU) can upregulate the expression of membrane-associated carcino-embryonic antigen (CEA), and MHC molecules in colon and breast carcinoma cell lines. We have investigated whether this drug can also enhance their sensitivity to the lytic effects of CEA-peptide specific Cytotoxic T cell lymphocytes (CTL). The CEA peptide-specific CTLs generated in our laboratory from normal HLA-A(*)02.01(+) donor PBMCs, were able to kill HLA-A(*)02.01(+)/CEA(+) breast (MCF-7-T103) and colon (HLA-A(*)02.01 gene-transfected HT-29 and C22.20) carcinoma cells in HLA-A(*)02.01 restricted manner. The treatment of target cells with 5-FU, enhanced their CEA expression and susceptibility to CTL-mediated lysis. Cold competition assays confirmed these results, thus supporting the hypothesis that immune target cell lysis and 5-FU mediated enhancement were dependent on CEA peptide presentation by cancer cells. 5-FU treatment of functionally "mature" CTL after in vitro expansion, did not reduce their cytolytic activity against MT-2 target cells but, when the anti-metabolite was added during the immune-sensitization phase, CTL generation was significantly inhibited. These results provide a rationale for investigating a possible new role of 5-FU as an immuno targeting amplifier agent in breast and colorectal cancer patients immunized with CEA-directed cancer vaccines.  相似文献   
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