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91.
The external nucleus of the inferior colliculus (ICx) receives ascending projections from both auditory and somatosensory nuclei. In the guinea pig, both the spinal trigeminal nucleus (TN) and the cochlear nucleus converge in the ventrolateral region of ICx. We investigated the function of trigeminal-collicular pathways by electrically stimulating the TN while recording unit responses from ICx. Pairing electrical stimulation with acoustic stimuli allowed us to investigate the function of converging auditory and somatosensory inputs, i.e. multisensory integration. Unit responses were recorded from ICx using a multi channel, single shank electrode. Electrical stimulation of the TN produced small changes above or below spontaneous rate, but resulted in significant suppression or enhancement of sound-evoked responses. Multisensory integration has been demonstrated in the dorsal cochlear nucleus (DCN), superior colliculus and sensory cortices and may play a role in plasticity that occurs after sensory deprivation.  相似文献   
92.
The aim of this study was to visualize, at the ultrastructural level, the deformation and failure mechanism of cartilage matrix in the tensile mode. Full-thickness dumbbell-shaped specimens were prepared from adult bovines. There were two specimen groups; in the 'parallel' group the specimen axis was parallel to the split lines defining the preferential orientation of the collagen in the articular surface, and in the 'perpendicular' group the specimen axis was perpendicular to the split lines. Specimens were placed with the articular surface uppermost and subjected to a graded series of strain within individual mini-tension devices, while observed with stereomicroscopy and confocal laser scanning microscopy. Thereafter, the changes in the ultrastructure were observed with both scanning and transmission electron microscopy. The mechanism of cartilage failure in the tensile mode comprised the following stages, whether the strain was applied parallel or perpendicular to the split line. (1) At 0% strain a fibrillar meshwork within the articular surface was predominantly orientated in the direction of the split line. (2) As strain increased, the fibrillar meshwork became more orientated in the parallel group and reorientated in the perpendicular group in the direction of the applied strain. (3) After complete reorientation of the fibrillar meshwork in the direction of the applied strain, the initial sign of failure was rupture of the fibrillar meshwork within the articular surface. (4) Subsequently, the rupture rapidly propagated into the deeper layers. Greater strains were required for fibrillar reorientation and complete rupture in the 'perpendicular group' than in the parallel group.  相似文献   
93.
Summary A case of a 44-year-old woman with a solitary pulmonary coin lesion is presented. Histologic study of this nodule revealed a normal intraparenchymal pulmonary lymph node. A review of the literature discusses the incidence and characteristics of this entity.
Nud lymphatique intrapulmonaire: revue de la littérature. A propos d'un cas
Résumé L'observation d'un cas de lésion nodulaire du poumon est rapportée chez une femme de 44 ans. L'étude histologique du nodule a révélé un nud lymphatique intrapulmonaire normal. La revue de la littérature apprécie l'incidence et les caractéristiques de cette localisation.
  相似文献   
94.
The total surgical experience of a supraregional paediatric cardiology unit over a nine year period (January 1980 to December 1988) was reviewed to assess the effect of the introduction of the full range of ultrasound techniques. A total of 1517 patients underwent cardiac surgery (955 cardiopulmonary bypass, 562 closed procedures). Of these, 485 patients (32%) did not undergo cardiac catheterisation before operation: 217 bypass (23% of all procedures under cardiopulmonary bypass) and 268 closed procedures (48%). The overall ratio of catheterisations to operations for patients undergoing palliative or corrective surgery fell from 0.97 (1980) to 0.38 (1988). The patients were classified as (a) neonates (0-28 days), (b) infants (one to 12 months), and (c) children (one to 14 years). The main impact of non-invasive surgical referral was in neonates (total catheter:operation ratio 0.38; neonates 0.2 for 1988). The surgical population was further divided according to the principal echocardiographic technique available: (a) 1980-4 cross sectional imaging; (b) 1985-6; imaging plus spectral Doppler ultrasound; (c) 1987-8; imaging plus spectral Doppler ultrasound and colour flow mapping. A fall in the catheter:operation ratio for all age groups was most pronounced in the last four years. This reflects increased familiarity and surgical confidence with non-invasive diagnostic assessment. The introduction of each new echocardiographic technique was associated with a significant fall in the total catheter:operation ratio compared with the preceding period. Six incorrect ultrasound diagnoses were made during the entire period; one of these patients died in the early postoperative period. The integration of Doppler ultrasound with cross sectional imaging has made non-invasive assessment an increasingly practical alternative to preoperative cardiac catheterization.  相似文献   
95.
The clinical, laboratory, and radiological features, including histocompatibility typing, of 28 patients with juvenile psoriatic arthritis are reported. The most common presentation was that of psoriasis preceding or occurring simultaneously with arthritis. The most common course of juvenile psoriatic arthritis was to start as an oligoarthritis and progress, usually to polyarthritis. No patients with juvenile psoriatic arthritis had uveitis. Overall, most patients had a good outcome (93% in functional class I and II), though 8/28 (29%) did require disease modifying drugs over a mean period of 8.8 years of follow up. The clinical features of these patients were very similar to those of a group of 158 adult patients with psoriatic arthritis with the same disease duration followed up in the clinic. Although there was an increased prevalence of B17 in both juvenile and adult psoriatic arthritis, juvenile psoriatic arthritis showed increased prevalence of A2, whereas adult psoriatic arthritis showed increased prevalence of B27, Bw39, and Cw6. This HLA association differed from that reported in other forms of juvenile arthritis.  相似文献   
96.
Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph.  相似文献   
97.
目的探讨急性脑出血患者卒中相关性肺炎(SAP)发生的危险因素,以便早期干预。方法选择急性脑出血患者196例为研究对象,其中发生SAP 82例为病例组,未发生SAP 114例为对照组。对两组的年龄、性别、心肺疾病史、GCS评分、吞咽困难、心率、血压、白细胞计数、脑出血量、鼻饲、使用胃黏膜保护剂和手术等共计23项予以比较分析。所得资料在单因素分析的基础上,又作多因素Logistic回归分析。结果急性脑出血SAP的患病率为41.837%。收缩压升高(优势比1.072,95%可信区间1.007~1.141,P=0.029)、白细胞计数增加(优势比1.331,95%可信区间1.009~1.756,P=0.043)、脑出血量增多(优势比1.079,95%可信区间1.019~1.142,P=0.010)、有心肺疾病(优势比12.275,95%可信区间1.210~124.545,P=0.034)、吞咽困难(优势比12.937,95%可信区间1.918~87.250,P=0.009)和鼻饲(优势比19.217,95%可信区间1.307~282.651,P=0.031)均促进发病。而使用胃黏膜保护剂(优势比0.157,95%可信区间0.031~0.790,P=0.025)和实施手术(优势比0.012,95%可信区间0.000~0.294,P=0.007)阻止发病。结论收缩压、白细胞计数增加、脑出血量增高、有心肺疾病、吞咽困难和鼻饲是急性脑出血发生SAP的危险因素;而使用胃黏膜保护剂和实施手术为其保护因素。  相似文献   
98.
The kidneys in paroxysmal nocturnal hemoglobinuria   总被引:6,自引:0,他引:6  
Long-term study of 21 PNH patients revealed an unexpectedly high incidence of functional and anatomic renal abnormalities. Most patients demonstrated varying degrees of hematuria and proteinuria distinct from hemoglobinuria. Evaluation of renal function revealed hyposthenuria, abnormal tubular function, and declining creatinine clearance. Radiologically these patients had enlarged kidneys, cortical infarcts, cortical thinning, and papillary necrosis which were confirmed by autopsy studies. Hypertension developed in eight patients. Urinary tract infection was uncommon. The renal findings bear striking similarity to those of sickle cell anemia. Contrary to the usual opinion, out studies clearly showed evidence of widespread renal pathology in PNH most likely due to repeated microvascular thrombosis similar to the venous thrombosis involving other organs in this disorder.  相似文献   
99.
100.
The use of downstaging prior to liver transplantation for hepatocellular carcinoma (HCC) still needs refinement. This study included patients with HCC listed for transplantation according to the Total Tumour Volume (TTV) ≤115 cm3 and alpha fetoprotein (AFP) ≤400 ng/ml criteria, with and without previous downstaging. Overall, 455 patients were listed, and 286 transplanted. Post‐transplant follow‐up was 38.5 ± 1.7 months. Patients downstaged to TTV115/AFP400 (n = 29) demonstrated similar disease‐free survivals (DFS, 74% vs. 80% at 5 years, P = 0.949), but a trend to more recurrences (14% vs. 5.8%, P = 0.10) than those always within TTV115/AFP400 (n = 257). Similarly, patients downstaged to Milan criteria (n = 80) demonstrated similar DFS (76% vs. 86% at 5 years, P = 0.258), but more recurrences (11% vs. 1.7%, P = 0.001) than those always within Milan (n = 177). Among patients downstaged to Milan, those originally beyond TTV115/AFP400 (n = 27) had similar outcomes as those originally beyond Milan, but within TTV115/AFP400 (n = 53). However, the likelihood of being within Milan at transplant was lower for patients with more advanced original HCCs (P < 0.0001). Overall, despite an expected increase in post‐transplant HCC recurrence, similar survivals can be achieved with and without downstaging, using the TTV115/AFP400 transplantation criteria, and including patients with advanced original HCCs. Downstaging should continue to be performed.  相似文献   
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