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101.
Hemangiopericytoma develops from many organs. In the central nervous system, most tumors arise in the intracranial portion, and tumors originating from the spinal cord are rare. Its clinical course and neurological characteristics have not been disclosed. We present a case of a 51-year-old woman with gradually progressing paraparesis. Magnetic resonance (MR) images of the thoracic spine demonstrated an intradural tumor at the 6 and 7 thoracic vertebral body level. The patient underwent total excision of the tumor. The histological diagnosis was hemangiopericytoma. MR images after the operation showed no residual tumor and the patient was followed up without adjuvant therapy. However, 5 years later, the patient complained of back pain and gait disturbance again, and MR images showed a recurrence of the tumor. We resected the tumor under motor evoked potential (MEP) monitoring and removed the extradural part of the tumor, but the part of the tumor which had infiltrated the spinal cord was left due to the lowering of MEP amplitude. The operation resulted in partial resection. Spinal intradural hemangiopericytoma is very rare, and only 15 cases including the present case have been reported. This paper will discuss the clinical characteristics and treatment for this tumor.  相似文献   
102.
The effects of left ventricular assist system (LVAS) implantation on renal hemodynamics remains to be fully elucidated. We evaluated renal function and intrarenal blood flow in five advanced heart failure patients who had been supported with a Toyobo LVAS for bridge to heart transplantation. Renal function expressed as estimated glomerular filtration rate (eGFR) was calculated using the modified formula of Modification of Diet in Renal Disease. Mean blood velocities in the bilateral segmental arteries during systolic and diastolic perfusion were measured using duplex Doppler sonography, and renal vascular resistance (resistive index [RI]) of the segmental arteries was defined as (peak systolic velocity [PSV]-end-diastolic velocity [EDV])/PSV. All studies were performed before and after implantation (mean duration of support, 15.6±10.9 months). LVAS implantation significantly improved eGFR (42.7±7.9 to 64.1±16.3mL/min, P<0.05). Beat-by-beat measurements of heart rate did not change significantly. Mean PSV decreased significantly (38.2±8.9 to 28.3±2.2cm/s, P<0.05), and mean EDV increased significantly (8.3±3.2 to 11.3±1.3cm/s, P<0.05), and thus, mean RI was significantly improved (0.79±0.06 to 0.60±0.04, P<0.01). In conclusion, in advanced heart failure patients, pulsatile LVAS implantation is associated with improved renal function, and this improvement may be mediated in part through an improvement of intrarenal hemodynamics.  相似文献   
103.
Objectives: To investigate and compare Wallace direct ureteroileal anastomosis with Le Duc anti‐reflux procedure in modified Studer orthotopic neobladder reconstruction after radical cystectomy. Methods: A total of 72 consecutive patients who underwent modified Studer orthotopic bladder reconstruction after a radical cystectomy for bladder cancer were investigated. They were examined for vesicoureteral reflux, hydronephrosis, and pyelonephritis at 6 months after surgery according to the type of ureteroileal anastomosis. Results: Vesicoureteral reflux occurred in 29 ureters (38.2%) after the Wallace procedure compared to six ureters (9.6%) with the Le Duc (P < 0.05). Hydronephrosis was detected in 12 ureters (18.8%) in the Le Duc patients compared to seven (9%) in the Wallace patients (P > 0.05). Six months after the operation, all three patients with vesicoureteral reflux‐related hydronephrosis improved using clean intermittent catheterization in the Le Duc patients; five of seven patients were cured by clean intermittent catheterization and two improved without any treatment in the Wallace patients. Seven of nine cases of ureteroileal anastomosis stenosis causing hydronephrosis were cured without any treatment but one case resulted in a non‐functional kidney despite treatment of the stenosis. Conclusions: Direct ureteroileal anastomosis using the Wallace method is effective for minimizing ureteroileal anastomosis stenosis and it represents a simple surgical procedure when combined with a modified Studer procedure.  相似文献   
104.
BackgroundAlthough lung transplantation from donation after cardiac death (DCD), especially uncontrolled DCD, is limited by warm ischemic periods, the molecular mechanism of warm ischemia–reperfusion-injury (IRI) has not been well elucidated. The purpose of this study was to clarify the particular longitudinal mechanisms of molecular factors involved in warm IRI.MethodsCold ischemic-time (CIT)-group lungs were retrieved and subjected to 3-h of cold preservation, whereas warm ischemic-time (WIT)-group lungs were retrieved after 3-h of warm ischemia. Orthotopic rat lung transplantation was performed and the grafts were reperfused for 1 or 4-h. The graft functions, gene expression, and activation of inflammatory molecules in the grafts were analyzed. Exhaled-carbon-monoxide-concentration (ExCO-C) was measured during reperfusion.ResultsOnly the WIT-group showed obvious primary graft dysfunction at 1-h reperfusion, but the graft function was recovered during 4-h reperfusion. Most of pro-inflammatory cytokines and stress-induced molecules showed different expression and activation patterns between CIT and WIT groups. In the WIT-group, the expressions of anti-inflammatory molecules, IL-10 and HO-1, were significantly increased at 1-h reperfusion compared to the CIT-group, and these high levels were maintained through 4-h reperfusion. Furthermore, ExCO-C levels in the WIT-group increased immediately after reperfusion compared to the CIT-group.ConclusionsThis study indicates that warm IRI may involve a different mechanism than cold IRI and anti-inflammatory pathways may play important roles in the graft recovery after lung transplantation from uncontrolled DCD.  相似文献   
105.

Background

Evolution of cryotherapy for prostate cancer is likely to result in parenchyma-sparing modifications adjacent to the urethra and neurovascular bundle. Results of initial series of focal therapy to minimize cryosurgery-related morbidity without compromising oncologic control have been encouraging, but limited in short-term outcomes.

Objective

To retrospectively report (1) median 3.7-yr follow-up experience of primary focal cryotherapy for clinically unilateral prostate cancer with oncologic and functional outcomes, and (2) matched-pair analysis with contemporaneous patients undergoing radical prostatectomy (RP).

Design, setting, and participants

Over 8.5 yr (September 2002 to March 2011), focal cryoablation (defined as ablation of one lobe) was performed in 73 carefully selected patients with biopsy-proven, clinically unilateral, low-intermediate risk prostate cancer. All patients underwent transrectal ultrasound (TRUS) and Doppler-guided sextant and targeted biopsies at entry.

Outcome measurements and statistical analysis

Post-therapy follow-up included measuring prostate-specific antigen (PSA) level every 3–6 mo; TRUS biopsies at 6–12 mo and yearly, as indicated; and validated symptom questionnaires. Matched-pair analysis compared oncologic outcomes of focal cryotherapy and RP (matched for age, PSA, clinical stage, and biopsy Gleason score).

Results and limitations

Complete follow-up was available in 70 patients (median follow-up: 3.7 yr; range: 1–8.5 yr). No patient died or developed metastases. Precryotherapy mean PSA was 5.9 ng/ml and Gleason score was 6 (n = 30) or 7 (n = 43). Postcryotherapy mean PSA was 1.6 ng/ml (70% reduction compared to precryotherapy; p < 0.001). Of 48 patients undergoing postcryotherapy biopsy, 36 (75%) had negative biopsies; positive biopsy for cancer (n = 12) occurred in the untreated contralateral (n = 11) or treated ipsilateral lobe (n = 1). Complete continence (no pads) and potency sufficient for intercourse were documented in 100% and 86% of patients, respectively. Matched-pair comparison of focal cryotherapy and RP revealed similar oncologic outcome, defined as needing salvage treatment.

Conclusions

Primary focal cryoablation for low-intermediate risk unilateral cancer affords encouraging oncologic and functional outcomes over a median 3.7-yr follow-up. Close surveillance with follow-up whole-gland biopsies is mandatory.  相似文献   
106.
BACKGROUND: E/e' and s' are thought to reflect left ventricular diastolic and systolic function, respectively. However, there are no reports on the combined use of E/e' and s' in predicting the outcome in acute myocardial infarction (AMI). METHODS: For 20?months beginning in October 2006, we enrolled 65 AMI patients who had undergone Swan-Ganz (SG) catheterization and echocardiography just after reperfusion therapy. We measured the cardiac index (CI) and the pulmonary capillary wedge pressure (PCWP) via an SG catheter and determined routine echocardiographic indices, including transmitral flow velocity (E), mitral annulus velocities at systole (s') and early diastole (e'), and E/e'. In addition, we rounded off the values of s' (cm/s) and E/e' (ratio of cm/s to cm/s) to the nearest integer, and designated them the s'-score and E/e'-score, respectively. We also defined the cardiac status score as the s'-score subtracted from the E/e'-score. In Study 1, we investigated the relationships between hemodynamic parameters (CI and PCWP) and echocardiographic indices, including the cardiac status score. In Study 2, we excluded patients with Killip class ≥II, yielding a final study population of 55 patients in whom we investigated whether the cardiac status score could predict adverse cardiac events. RESULTS: Only the cardiac status score significantly correlated with both the PCWP and the CI. In the Cox proportional hazards model, significant predictors were the left ventricular ejection fraction (LVEF), estimated glomerular filtration rate (eGFR), and cardiac score ≥3.0. CONCLUSIONS: The novel score achieved in this study by subtracting the s'-score from the E/e'-score could be highly useful for predicting outcomes in AMI with Killip class I.  相似文献   
107.
108.
The ligamentum flavum is considered to be one of the important causes of radiculopathy in lumbar degenerative disease. Although there have been several reports anatomically examining the positional relationship between the ligamentum flavum and nerve root, there are few reports on ventral observation. The purpose of this study is to clarify the shape of the ligamentum flavum seen ventrally, and to obtain anatomic findings related to nerve root compression. The subjects were 18 adult embalmed cadavers, with an average age of 78 years at the time of death. The ventral shapes of the ligamentum flavum were observed. The relationships between the morphological change of the ligamentum flavum and nerve root compression or radiographic findings were statistically evaluated. Among the shapes of the ligamentum flavum, bulging of the ligament was most frequently observed. Proximal bulging indicates the type with the cranial portion bulging from the subarticular zone to the foraminal zone of the ligamentum flavum. In this type associated with a decrease in disc height, nerve root compression was frequently observed. Thus, we could more realistically grasp the relationship between bulging morphology of the ligamentum flavum and nerve root compression.  相似文献   
109.
Carotid endarterectomy (CEA) is the main treatment for atherosclerotic plaque of the cervical internal carotid artery. The surgical anatomy of the carotid arteries was studied in the carotid triangle of 49 cadavers. The carotid bifurcation was located at the level of the lower third of C-3. The superior thyroid artery arose from the anterior wall of the external carotid artery in 70% of specimens and from the distal portion of the common carotid artery in 30%. The lingual artery arose as a separate trunk between the origins of the superior thyroid and facial arteries in 81% of specimens, with the facial artery from a common trunk in 18%, and with the superior thyroid artery in 1%. The occipital artery arose from the posterior aspect of the external carotid artery above the level of origin of the facial artery in 57% of specimens, between the origins of the facial and lingual arteries in 32%, and below the origin of the lingual artery in 11%. The origin of the occipital artery was positioned low and the distal portion of the occipital artery was crossed by the hypoglossal nerve in 20%. The ascending pharyngeal artery arose from the posterior wall of the external carotid artery above the level of origin of the lingual artery in 66% of specimens, below the origin of the lingual artery in 9%, from the proximal portion of the occipital artery in 19%, from the carotid bifurcation in 2%, and from the internal carotid artery in 2%. The branches of the external carotid artery are the key landmarks for adequate exposure and appropriate placement of cross-clamps on the carotid arteries. It is necessary to understand the surgical anatomy of the carotid arteries to carry out successful removal of plaque and minimize postoperative complications in a bloodless surgical field.  相似文献   
110.
PURPOSE: To clarify whether propofol administration during thoracic or lumbar epidural anaesthesia intensifies the haemodynamic depression associated with epidural anaesthesia. METHODS: Patients (n = 45) undergoing procedures of similar magnitude were randomly divided into three study groups: a control group (n = 15) receiving general anaesthesia alone and two study groups undergoing thoracic (n = 15) and lumbar epidural anaesthesia (n = 15) before induction of general anaesthesia. All patients received 2 mg.kg-1 propofol at a rate of 200 mg.min-1, followed by a continuous infusion of 4 mg.kg-1.hr-1. Mean arterial blood pressure (MAP) and heart rate (HR) were measured at baseline, three minutes after induction, and one minute after tracheal intubation in all three groups and at 20 min after epidural anaesthesia was established in the thoracic and lumbar groups. RESULTS: Following epidural anaesthesia, MAP decreased from 94 +/- 14 (SD) at baseline to 75 +/- 11 mmHg (P < 0.0001) in the thoracic group and from 92 +/- 12 to 83 +/- 15 mmHg in the lumbar group. After propofol administration, MAP decreased further in the thoracic group to 63 +/- 9 mmHg (P = 0.0077) and to 67 +/- 10 mmHg (P = 0.0076) in the lumbar group. The MAP following propofol induction in the thoracic group (P < 0.0001) and in the lumbar group (P = 0.0001) was lower than MAP in the control group (81 +/- 9 mmHg). HR decreased only in response to thoracic epidural anaesthesia (P = 0.0066). CONCLUSION: The hypotensive effects of propofol are additive to those of epidural anaesthesia, resulting in a profound decrease in mean arterial pressure.  相似文献   
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