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61.
62.
We successfully saved a patient with appendicitis followed by necrotizing fascitis. A 77-year-old man with a history of ambulatory treatment for depression underwent an emergency operation because of severe abdominal pain. Laparotomy demonstrated that necrotizing appendicitis was massively extending over the abdominal cavity, involving the right paracolic sulcus and Douglas pouch and posterior surface of the right kidney. Irrespective of the emergency surgery, redness and swelling in the right chest and abdomen, which was noted at the time of admission, was not decreased. Successively, a retension incision was performed under the diagnosis of necrotizing fasciitis. Necrotizing fasciitis is an extremely rare complication of appendicitis, and there were only 10 cases documented. Once necrotizing fasciitis occurs, the mortality rate is high, so that correct diagnosis and prompt debridement are mandatory. Particularly for elderly patients with appendicitis, rapid and accurate diagnosis and treatment are required.  相似文献   
63.
To evaluate the effect of cable nerve graft polarity, the bilateral common peroneal nerves in 12 rabbits were excised to create 20-mm nerve gaps. These gaps were repaired with cable grafts using three strands of 20-mm ipsilateral sural nerves. In the left leg, the sural nerves were grafted with the original orientation. In the right leg, the nerve graft polarity was reversed 180 degrees. Six months later, motor conduction velocities were evaluated, and the bilateral anterior tibial muscles and extensor digitorum longus muscles were measured. The nerves were harvested and analyzed histologically. Motor conduction velocity was 37.4+/-4.1 m/s in the reversed group, and 36.6+/-5.5 m/s in the control group. The weight of the muscles was 7.2+/-0.8 g in the reversed orientation, and 7.0+/-1.0 g in the original orientation. None of the differences was statistically significant. Histologically, the axon counts and the axonal density distal to the nerve graft also showed no differences between groups. The sural nerves used did not have a major branch and their diameter was almost the same throughout its length. Reversing nerve graft polarity of a cable graft did not affect nerve regeneration electrophysiologically or histologically.  相似文献   
64.
This study describes a new technique to evaluate accurate linear polyethylene wear and reports the in vivo annual linear wear rate in total knee arthroplasty. Patients (n = 69) were assessed using a single standing anteroposterior radiograph with 8 reference markers around the knee, where 3-dimensional (3D) locations of markers and 3D geometry of the implant were known. By matching the 3D locations of the markers and their projected points on the radiograph, 3D/2D transformation parameters were estimated. Using these parameters, the 3D coordinates of the implant were estimated from the projected x-ray silhouette. After calculating the femorotibial shortest distance, wear and creep deformity of the polyethylene was defined with an accuracy of 0.1 mm or better. Measured linear wear in the 69 knees varied from 0 mm (1 month postoperatively) to 2.71 mm (7 years postoperatively). The correlation of linear wear (Y) and year (X) was Y = 0.23 X -0.11 (P<.001). This study revealed that annual wear rate was 0.23 mm and 2 times greater than the average annual wear rate in total hip arthroplasties.  相似文献   
65.
OBJECTIVE: To describe hemodynamic improvement in a patient treated with nitric oxide (NO) inhalation in the management of right ventricular failure caused by myocardial infarction. DESIGN: Case report. SETTING: An intensive care unit of a university hospital. PATIENT: A 66-yr-old man with severe right ventricular failure caused by acute myocardial infarction. INTERVENTIONS: Nitric oxide inhalation through a ventilator circuit. MEASUREMENTS AND MAIN RESULTS: The patient complained of chest pain. When myocardial infarction was diagnosed, he underwent percutaneous transluminal coronary angioplasty and percutaneous transluminal coronary recanalization, but they were not effective. We instituted intra-aortic balloon pumping and brought the patient to the intensive care unit (ICU). Even with high-dose inotropic support, his hemodynamics deteriorated gradually. On the patient's seventh day in the ICU, we started NO inhalation at 5-10 ppm in an attempt to relieve his right heart failure. Immediately after NO inhalation was started, his hemodynamics improved significantly, and we could wean the patient from intra-aortic balloon pumping. NO inhalation was continued for 9 days and was successfully discontinued without circulatory deterioration. He was discharged from our hospital uneventfully. CONCLUSION: Nitric oxide inhalation improved hemodynamics in our patient with right ventricular failure after myocardial infarction. Our report suggests that a clinical trial of NO treatment for severe right ventricular failure caused by myocardial infarction is warranted.  相似文献   
66.
The present study updates results on methodology of quantitation of tumor neovascularization and those on the prognostic value of microvessel density (MVD) in breast cancer tissue previously published in the World J. Surg. 21: 49–56, 1997. The followup period of observation of the series was extended to 20 years, and new biological indicators (i.e., proliferating cell nuclear antigen (PCNA), cerbB2, and p53) were included in the analysis. There were 109 patients with primary breast cancer, from 1971 to 1979, followed up for a median of 14 years (range, 1–20). A representative median longitudinal section of each breast tumor was immunohistochemically stained with factor VIIIrelated antigen and analyzed. The three methods of identifying MVD were: (1) average microvessel count (AMC)/mm2, (2) central microvessel count (CMC)/mm2, and (3) highest microvessel count (HMC)/mm2. Thirtyone patients (28.4%) died of breast cancer. There was a relationship between MVD and peritumor blood vessel invasion (AMC: p = 0.0114, CMC: p = 0.0319, and HMC: p = 0.0009). However, there was no relationship between MVD and other factors. Univariate analysis showed that node status (p < 0.0001), histological grade (p < 0.0001), clinical tumor size (T) (p = 0.0002), PCNA (p = 0.0033), p53 (p = 0.0043), mitotic grade (p = 0.0092), AMC (p = 0.0214), and peritumor lymphatic vessel invasion (p = 0.0467) were significantly predictive of overall survival. HMC was borderline significant (p = 0.0702), while CMC and cerbB2 were not significant. Multivariate analysis showed that T (p = 0.0005), node status (p = 0.0053), and AMC (p = 0.0485) were independent factors, but neither CMC nor HMC was independent. AMC, a significant independent prognostic factor, might be a better method than the others for evaluating angiogenesis, but further and larger studies are warranted.  相似文献   
67.
68.
Bradykinin (BK) is an inflammatory mediator that plays a pivotal role in pain and hyperalgesia to heat in inflamed tissues by exciting nociceptors and sensitizing them to heat through activation of protein kinase C (PKC). It has been suggested that the capsaicin receptor (VR1), a nociceptor-specific cation channel sensitive to noxious heat, protons, and capsaicin, is a channel that is modified by BK in these effects. In this study, we examined how BK modulates the activity of VR1. We measured VR1 currents using the patch-clamp technique in human embryonic kidney-derived (HEK293) cells expressing VR1 and B2 BK receptor. We found that BK lowered the threshold temperature for activation of VR1 currents in HEK cells down to well below the physiological body temperature in a concentration-dependent manner through PKC activation. We also demonstrated that in capsaicin-sensitive dorsal root ganglion (DRG) neurons the activation threshold of heat-induced current, which is considered to be VR-1 mediated, was lowered by BK and that this effect was also mediated by PKC. These data further support the supposition that modulation of VR1 is a mechanism for the BK-induced excitation of nociceptors and their sensitization to heat.  相似文献   
69.
To evaluate the diagnostic yield of the procedure, mucosal-incision assisted biopsy (MIAB), for the histological diagnosis of gastric gastrointestinal stromal tumor (GIST), we performed a retrospective review of the 27 patients with suspected gastric GIST who underwent MIAB in our hospitals. Tissue samples obtained by MIAB were sufficient to make a histological diagnosis (diagnostic MIAB) in 23 out of the 27 patients, where the lesions had intraluminal growth patterns. Alternatively, the samples were insufficient (non-diagnosticMIAB) in remaining 4 patients, three of whom had gastric submucosal tumor with extraluminal growth patterns. Although endoscopic ultrasound and fine needle aspiration is the gold standard for obtaining tissue specimens for histological and cytological analysis of suspected gastric GISTs, MIAB can be used as an alternative method for obtaining biopsy specimens of lesions with an intraluminal growth pattern.  相似文献   
70.
Abstract: In order to analyze the origin of the rhythmical fluctuations in the cardiovascular system, an artificial heart, which does not have rhythmical periodicities such as altering heart rate and cardiac function, was utilized in chronic animal experiments with adult goats. Two pneumatically actuated ventricular assist devices were implanted as a total biventricular bypass under general anesthesia, and then the natural heart was electrically fibrillated to constitute the biventricular bypass type of complete prosthetic circulation model. All hemodynamic data were recorded under awake conditions and were calculated in the computer system by spectral analysis methods. In the power spectrum of the arterial blood pressure of the animal with the artificial heart, the Mayer wave peak and respiratory wave peak were clearly observed, and spectral analysis including the coherence function suggests that the Mayer waves originated from the peripheral vascular resistance and the respiratory waves probably originated from the periodicities of the pulmonary circulation. These fluctuations in the circulatory system influenced the arterial baroreflex system and transfer to the sympathetic outflow through the central baroreflex system, which suggests that rhythmical fluctuations in hemodynamic parameters originate at least in part from these vascular periodicities.  相似文献   
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