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201.
We present a case of Epstein-Barr virus (EBV)-associated primary central nervous system lymphoma (PCNSL) arising from a patient with cutaneous-type adult T-cell leukemia/lymphoma (ATLL). Extranodal sites affected by ATLL include the skin, lung, liver, gastrointestinal tract and central nervous system (CNS). CNS involvement usually occurs as an acute and lymphoma-type ATLL. PCNSL is a rare type of tumor and the vast majority of PCNSL are of B-cell lineage. Individuals with acquired, iatrogenic or congenital immunodeficiency are at increased risk of PCNSL, which is commonly associated with EBV. In our patient, the expression of latent infection membrane protein 1 (LMP1), EBV nuclear antigen 2 (EBNA2), and EBV-encoded small RNA (EBER) in tumor cells confirmed a type III latency of EBV infection. Human T-cell lymphotropic virus type I (HTLV-I) can induce immunodeficiency before the overt development of ATLL. The HTLV-I infection led to suppression of the immune system and the development of EBV-associated PCNSL. This is the first reported case of the clinicopathological features of EBV-associated PCNSL arising from a patient with ATLL.  相似文献   
202.
CONCLUSIONS: Habitual sniffing is a significant contributing factor to the development of postoperative retraction of the reconstructed posterior meatal wall and tympanic membrane, although it still seems a multifactorial event. OBJECTIVE: To examine the possible contribution of habitual sniffing to retraction-type middle ear pathology in a more direct way than previous reports. PATIENTS AND METHODS: The correlation between habitual sniffing and the postoperative configuration of the posterior meatal wall was examined in 58 patients with cholesteatoma who underwent tympanoplasty with reconstruction of the soft meatal wall. RESULTS: The postoperative configuration of the posterior meatal wall showed severe retraction in 7 of 8 patients with habitual sniffing, but only 22 of 47 without habitual sniffing. Habitual sniffing was significantly associated with postoperative severe retraction (Fisher's exact test, p<0.05).  相似文献   
203.
Involvement of pterygoid venous plexus in patulous eustachian tube symptoms   总被引:1,自引:0,他引:1  
CONCLUSIONS: The pterygoid venous plexus (PVP) is an important factor in the mechanism of eustachian tube (ET) closure under conditions that can cause increased venous pressure in the head, such as during neck compression and postural change from the sitting/standing to the recumbent position. OBJECTIVES: The symptoms of patulous ET are usually improved by neck compression or postural change (from sitting/standing to recumbent position). Venous congestion around the ET and/or gravitational change may be involved in the changing degree of symptoms, but its mechanism is not understood. This study investigated whether the PVP is involved. MATERIALS AND METHODS: The dimensions of soft tissues surrounding ET were measured on magnetic resonance images before and after neck compression. RESULTS: The lateral pterygoid muscle became enlarged after neck compression. Simultaneously, the volume of venous plexus observed between the medial pterygoid muscle and tensor veli palatini muscle was increased. Such enlargement was probably due to blood pooling in the PVP, resulting in protrusion of the ET anterior wall to the luminal side, and decreased ET patency.  相似文献   
204.
CONCLUSIONS: Quality of hearing is one of the key conditions promoting habitual sniffing associated with closing failure of the Eustachian tube and sniffing may stop with deterioration of hearing due to progression of the disease. OBJECTIVE: To examine habitual sniffing associated with closing failure of the Eustachian tube and hearing level in patients with cholesteatoma. PATIENTS AND METHODS: A total of 171 patients with middle ear cholesteatoma treated in Tohoku University Hospital (106 sides in 101 patients, 63 males and 38 females, mean age 43.3 years), and Sendai Ear Surgi Center (70 sides in 70 patients, 37 males and 33 females, mean age 42.7 years) were included. The patients were divided into two groups based on the presence or absence of habitual sniffing, and pre- and postoperative hearing was compared between the two groups. RESULTS: Habitual sniffing was not found in patients with air conduction hearing level worse than 60 dB or air-bone gap larger than 40 dB. Habitual sniffing disappeared in all patients with expanded air-bone gaps in lower frequency regions after surgery.  相似文献   
205.
206.
Internal auditory canal anomalies are rare. Narrow internal auditory canal is believed to occur as a result of aplasia or hypoplasia of the vestibulocochlear nerve. Narrow duplication of the internal auditory canal is considered to be very rare. Narrow duplication of the internal auditory canal with inner ear malformation has been reported in only 3 cases. We present 2 cases of narrow duplication of the internal auditory canal with inner ear malformation. The first case had inner ear malformation on only one side and the second case had inner ear malformation on both sides. The embryogenesis may be different between internal auditory canal and inner ear.  相似文献   
207.
Three patients with a middle ear malformation characterized by the absence of the oval window and complicated by facial nerve anomalies were treated by surgery. Hearing ability of all the patients was improved. A variety of facial nerve anomalies were observed. Fenestration of the vestibule above the facial nerve was performed in the case of 2 of the 3 patients. In the other patient, fenestration of the scala vestibuli below the facial nerve was performed. In the case of all the 3 patients, hearing ability improved after the surgery and remained stable for a long time. Surgery for this disease has been considered difficult because of a high risk of complications. Because all the 3 patients showed excellent long-term surgical results, we suggest that fenestration of the inner ear should be considered one of the main options for the management and treatment of an absent oval window associated with facial nerve anomalies.  相似文献   
208.
PURPOSE: Using a lipopolysaccharide (LPS)-treated porcine model, we examined: (1) whether nitric oxide (NO), anandamide, and tetrahydrobiopterin (BH4) increased or not in early endotoxic shock; and (2) the location of the major site of production of these molecules, by comparing their concentrations in arteries and the portal and hepatic veins. METHODS: Ten pigs received an infusion of LPS at 1.7 microg x kg(-1)x h(-1) via the portal vein for 240 min. Consecutive changes in systemic hemodynamics, hepatosplanchnic circulation, and oxygen delivery were measured. Furthermore, the variable changes in the concentrations of nitrite and nitrate (NOx), anandamide, and BH4 were measured. To access the effects of surgery, anesthesia, and fluid management on BH4, an experiment without LPS infusion was performed in two other animals. RESULTS: Mean arterial pressure and cardiac index started to decrease at 60 min after LPS infusion. However, systemic vascular resistance remained unchanged. Total hepatic blood flow and hepatic oxygen delivery also decreased significantly. NOx and anandamide did not change during LPS infusion. BH4 values did not change without LPS infusion. However, BH4 values increased significantly in the arterial, portal, and hepatic circulation during LPS infusion, especially in the hepatic vein (from 136.8 +/- 27.5 to 281.3 +/- 123.2 mol/ml; P < 0.01). CONCLUSION: Our data suggest that the BH4 values were significantly increased in several organs, especially in the liver during endotoxic shock. Impaired cardiac output and decreased blood pressure appeared in the early phase of porcine endotoxemia. Longer-term observation of these parameters after LPS treatment should be performed as the next step in future studies.  相似文献   
209.
We evaluated the relationship between regional cerebral blood flow (rCBF) and clinical symptoms in patients with schizophrenia. Single photon emission computed tomography with N-isopropyl-p-[123I]iodoamphetamine (123I-IMP) was used to study 29 patients with schizophrenia. Clinical symptoms were assessed using the Brief Psychiatric Rating Scale (BPRS). We examined the correlation between rCBF and each BPRS item score using Statistical Parametric Mapping software. Corrected P-values < 0.05 were considered as statistically significant. The suspiciousness score on the BPRS was positively correlated with rCBF in the left inferior temporal gyrus. There was no significant correlation between rCBF and any other items of the BPRS. There was no significant correlation between rCBF and chlorpromazine-equivalent dosage. This analysis permits the quantitative assessment of the severity of persecutory delusions in relation to left temporal perfusion in patients with schizophrenia.  相似文献   
210.
Phrenic nerve impairment can often lead to serious respiratory disorders under various pathological conditions. During routine dissection of an 88-year-old Japanese male cadaver, a victim of heart failure, we recognized an extremely rare variation of the right thyrocervical trunk arising from the subclavian artery laterally to the anterior scalene muscle. In addition to that, the ipsilateral phrenic nerve was drawn and displaced remarkably laterad by this vessel. We examined all of the branches arising from subclavian arteries, phrenic nerves and diaphragm muscles. The embryological background of this arterial variation is considered. The marked displacement with prolonged strain had a potential to cause phrenic nerve impairment with an atrophic change of the diaphragm muscle. Recently many image diagnostic technologies have been developed and are often used. However, it is still possible that rare variations like this case may be overlooked and can only be recognized by intimate regional examination while keeping these rare variations in mind.  相似文献   
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