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31.
Vuillet J Kerkerian-Le Goff L Kachidian P Dusticier G Bosler O Nieoullon A 《The European journal of neuroscience》1990,2(8):672-681
Dual labelling methods were applied to localize simultaneously neuropeptide Y (NPY) and glutamate decarboxylase (GAD) immunoreactivities on ultrathin sections of the rat caudate-putamen (CP). By means of a double peroxidase-anti-peroxidase technique, using 3,3'-diaminobenzidine and benzidine dihydrochloride as chromogens in animals with no colchicine pretreatment, GAD immunoreactivity was found to be present in terminals only whereas NPY immunoreactivity was detected in neurons displaying the features of aspiny type cells and processes. With this approach, we observed numerous synaptic associations of the symmetrical type between GAD-immunoreactive (-Ir) axonal boutons and NPY-Ir cell bodies and dendrites. By combining immunoperoxidase and radioimmunocytochemical labelling in animals pretreated with colchicine, NPY was again detected in a single population of aspiny type neurons whereas GAD immunoreactivity was observed in neurons which could be classified as aspiny and spiny on the basis of their ultrastructural characteristics. All the cells of the aspiny type displaying clear-cut NPY immunoreactivity were also found to be GAD-positive. Some other neurons of both the aspiny and the spiny type were found to be immunoreactive to GAD alone. GAD/NPY dually labelled terminals were also observed and some axo-axonic appositions between GAD- and NPY-Ir terminals were also detected. All in all, these data show that NPY aspiny type neurons of the rat CP receive GABAergic afferents and provide morphological support for two hypotheses: that NPY is co-localized with GABA in some cell bodies, dendrites and axons, and that presynaptic interactions may occur between NPY and GABAergic neuronal systems. 相似文献
32.
Lack of Influence of Atrioventricular Delay on Stroke Volume at Rest in Patients with Complete Atrioventricular Block and Dual Chamber Pacing 总被引:1,自引:0,他引:1
ERALDO OCCHETTA CRISTINA PICCININO GABRIELLA FRANCALACCI REA MAGNANI LEONARDO BOLOGNESE PAOLO DEVECCHI GIORGIO ROGNONI PAOLO ROSSI 《Pacing and clinical electrophysiology : PACE》1990,13(7):916-926
Dual chamber pacing (DDD) maintains atrioventricular (AV) sequence; AV delay programmability modifies the relationship between atrial and ventricular contraction. To evaluate the hemodynamic effects of such a modification, ten patients with a DDD unit for complete AV block were studied by time-motion (M-mode) and Doppler echocardiography during inhibited ventricular pacing (VVI), atrial-triggered ventricular pacing (VDD) and atrioventricular sequential pacing (DVI) at different AV delay (90, 140, 190, 240 msec). A significant improvement in stroke volume (SV) (15%-20%, P less than 0.05) was seen during DDD versus VVI pacing; no changes, however, were observed in the same patient with different AV delay or during DVI versus VDD pacing. These data suggest that programming of AV delay does not affect systolic performance at rest; longer diastolic filling times recorded during DDD pacing with "short" AV delay (90-140 msec) do not seem to be a hemodynamically relevant epi-phenomenon of PM programming. 相似文献
33.
目的 探讨螺旋CT双期扫描对肝脏占位性病变的诊断价值。方法 对98例肝内占位性病变的病人进行螺旋CT双期增强扫描。结果 98例病人中肝癌48例,肝转移瘤19例,肝血管瘤31例。结论 螺旋CT扫描速度快,在动脉期和门静脉期分别完成全肝扫描,弥补了一般动态扫描的缺点,对肝内病灶的检出和定性有重要价值。 相似文献
34.
Characteristics of bone mineral density and soft tissue composition of obese Japanese women: Application of dual-energy X-ray absorptiometry 总被引:2,自引:0,他引:2
We studied the characteristics of bone mineral density (BMD) and soft tissue composition in obese Japanese women using dual-energy
X-ray absorptiometry. Eighty-nine women, aged 45–85 years, were divided into three groups according to their body mass index
(BMI): a thin group (n = 38; BMI < 21), a standard weight group (n = 31; BMI, 21–25), and an obese group (n = 20; BMI ≥ 25). The mean BMD of the second to fourth lumbar vertebrae and BMD of the lumbar spine, thoracic spine, pelvis,
legs, and ribs of the thin group were significantly lower than those of the standard weight group or the obese group (P < 0.05), whereas no significant difference in total body BMD was observed among the three groups. There was a significant
difference in total and regional fat mass among the three groups (P < 0.05). Lean mass of legs and total lean mass showed a significant difference between the thin group and the obese group
(P < 0.05). The results showed that obesity was associated with higher BMD of weight bearing-bones and ribs, high total and
regional fat mass, and high lean mass of bilateral legs and total lean mass. We suggest that obesity may contribute to the
prevention of bone loss of weight-bearing bones and ribs and muscular atrophy of the legs.
Received: Sept. 30, 1998 / Accepted: Dec. 10, 1998 相似文献
35.
Evaluation of esophageal bile reflux after total gastrectomy by gastrointestinal and hepatobiliary dual scintigraphy 总被引:2,自引:0,他引:2
Conducting the qualitative evaluation of reconstruction methods is difficult because of their complexity. The aim of the present
study was to compare esophageal bile and food reflux by performing gastrointestinal and hepatobiliary dual scintigraphy (GHDS)
after various methods of reconstruction following total gastrectomy. Of 17 patients studied, 4 had undergone Roux-en-Y anastomoses
(R-Y); 6, jejunal pouch-Y anastomoses (P-Y); and 7, jejunal pouch interposition (P-I). GHDS was performed 1 year after surgery
using111In-diethylene triamine pentaacetic acid administered orally, and99mTc-pyridoxyl-5-methyl tryptophan administered intravenously. Imaging data from a gamma camera were stored in and processed
by a data analyzer. Three patients who had undergone R-Y and one who had undergone P-I complained of heartburn, while one
who had undergone R-Y, two who had undergone P-Y, and three who had undergone P-I complained of a feeling of fullness. Esophageal
bile reflux was confirmed by GHDS in four of the patients who had undergone R-Y, one who had undergone P-Y, and four who had
undergone P-I. Moreover, GHDS demonstrated food retention in two patients who had undergone R-Y, five who had undergone P-Y,
and four who had undergone P-I. Weight loss was closely related to the esophageal reflux of bile or food which can be accurately
detected by GHDS. Despite the absence of heartburn, patients diagnosed as having bile reflux by GHDS showed poor recovery
of body weight. 相似文献
36.
37.
Transarterial left ventricular assist devices (LVADs), such as the Hemopump, IABP, and PUCA-pump, are meant to be introduced into the body via the femoral or axillary artery without major surgery. For certain applications, introduction is performed directly into the aorta via an open thorax procedure. A prototype of a vascular access device has been realized that allows direct access into the aorta as an alternative for the common surgical graft anastomosis suturing technique. The device consists of a metal tube acting as a circular knife to cut a hole in the aortic wall, a screw to store the removed part of the aortic wall, and a plastic tube that is introduced through the hole and tightly connected to the aortic wall. The device could be placed without aortic clamping. The device has been tested on a slaughterhouse porcine aorta. A low-pressurized aorta appeared to be the worst case; thus, two animal experiments in the low-pressurized pulmonary artery were performed. No leakage occurred for pressures between 40 and 300 mm Hg. 相似文献
38.
Chapenko S Folkmane I Tomsone V Amerika D Rozentals R Murovska M 《Clinical transplantation》2000,14(5):486-492
The ubiquity of human cytomegalovirus (CMV) and human herpesvirus-7 (HHV-7), as well as activation of these viruses during immunosuppression, allows the suggestion that both viruses could participate in the development of 'CMV disease' in patients after renal transplantation (RT). The aim of our research was to study the prevalence of latent CMV and HHV-7 infections in patients before RT, to determine interaction between these viruses in dual infection and possible association of their reactivation with the progression of 'CMV disease' after RT. Peripheral blood samples were collected from 49 patients before and up to 10-12 wk after RT. The methods used for diagnostics of viral infections were: serology, nested polymerase chain reaction (nPCR) analysis of peripheral blood leukocytes (PBL) and plasma, and virus isolation in cell cultures (morphological changes, nPCR analysis of cellular and cell-free samples, indirect immunofluorescence analysis). Before RT, CMV and HHV-7 DNAs were detected in PBL but not in the plasma samples, which indicates the presence of latent viral infection in patients. Latent dual (CMV + HHV-7) infection was prevalent (51.0%) in 49 patients, while CMV and HHV-7 infections alone were detected in 26.5 and 12.2% of patients, respectively. Risk of viral disease after RT, for recipients with latent dual infection before RT, was 12- and 2.2-fold higher in comparison with CMV and HHV-7 infections alone, respectively. Frequency of dual infection in 18 recipients with 'viral syndrome' or 'CMV disease' after RT was reliably higher (13/18, 81.3%) than CMV (1/18, 6.2%) (p < 0.025) and HHV-7 (2/18, 12.5%) (p < 0.025) infections alone. HHV-7 reactivation preceded CMV reactivation in 77.0% of the cases of dual infection in the recipients with viral disease and reactivation of both viruses preceded the development of viral disease. Severe 'CMV disease' developed in 2 out of 2 recipients with CMV primary infection and 'viral syndrome' in 1 recipient with CMV reinfection. The reactivation of CMV was detected in all recipients prior to onset of the disease. Correlation was shown between reactivation of latent HHV-7 infection and development of febrile syndrome in 2 out of 2 recipients with HHV-7 infection alone. Taking into account that dual infection is an increased risk factor for 'viral syndrome' and 'CMV disease' development, screening diagnostic should include testing for both viral infections in transplant donors as well as in recipients before and after RT. 相似文献
39.
G Rattray S Hopley N Mason M Jenkins 《Journal of Medical Imaging and Radiation Oncology》1998,42(2):118-125
The aim of this study was to evaluate the improvement in patient comfort and field positional accuracy provided by a new pelvic stabilization system when delivering multiple field radiotherapy to the pelvis. The Pelvic Cradle (BEHTS Manufacturing, Brisbane, Qld, Australia) is a stabilization device that provides reproducible patient positioning and levelling. Ninety patients were randomized into three groups. The first group was treated using the Pelvic Cradle, the second group was treated using current stabilization practices, and the third group was treated using the Pron Pillo (Chattanooga Pharmacal Company, USA) and current stabilization practices. Port films were assessed for field displacement in the lateral and cranio-caudal directions. A patient survey was used to evaluate the patient's perception of comfort while receiving treatment. When compared to the control group, the pelvic cradle group demonstrated a 48% improvement in the mean lateral deviation from 3.8 mm to 2.0 mm (P < 0.001) and a 36% improvement in the mean cranio-caudal deviation from3.9 mm to 2.5 mm (P < 0.001). The Pelvic Cradle was found to provide an improved level of field positional accuracy while maintaining patient comfort. 相似文献
40.
本文介绍在域中如何实现系统远程控制,具体说明了如何配置Pcanywhere、域中实现远程安装、以及能够实现的一些功能。 相似文献