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81.
At the National Cancer Center Hospital in Tokyo, a patient withBarrett's esophagus developed double adenocarcinoma of the esophagus.One carcinoma was located in the midesophagus and the otherjust above the anatomic cardia. Esophagoscopic examination withbiopsy revealed two carcinomas surrounded with columnar epitheliumand ectopic islets of gastric mucosa situated in the postcricoidregion. There was no ulcer or stricture in the esophagus. Thepatient received subtotal esophagectomy and survived the operation.Microscopically, depth of invasion of the proximal cancer wasto the proper muscle, and that of the distal one was to thesubmucosal layer. There was metastasis to two lymph nodes. Therewas no sign of inflammation or ulcer in the esophagus.  相似文献   
82.
Respiratory vagal activity is expressed by heart rate variability (HRV) at approximately 1 month of age in premature low-birth-weight infants (PLBWI). However, the autonomic inputs into the sinus node (SAN) and atrioventricular node (AVN) in PLBWI are unclear. We evaluated the variability in PP and PR intervals at day zero (day 0) and 1 month (1 month) after birth in 16 PLBWI (gestation 32.3 ± 1.3 weeks, birth weight 1.578 ± 257 g). The polygraph was recorded during sleep on day 0 and at 1 month. PP and PR intervals and the number of respiratory cycles were measured, and frequency analysis was performed by auto-correlation fast Fourier transforms. Power spectral density (PSD: ms2) was calculated for the low frequency domain (LF: 0.036∼0.146 Hz), high frequency domain (HF: 0.146∼0.390 Hz), total frequency (TF: 0.036∼2.000 Hz), and respiratory sinus arrhythmia (RSA: frequency bandwidth of 0.3 Hz with peak respiratory frequency as median), and the PSD ratio in the PP and PR intervals (LF/HF, RSA/TF) were compared. Compared with day 0, a decrease in the LF/HF ratio and an increase in the RSA/TF ratio in PP intervals were observed at 1 month, consistent with expression of respiratory vagal activity. For PR intervals, on the other hand, the LF/HF ratio increased, indicative of accentuated sympathetic activity. However, the respiratory vagal input was weak, and the RSA/TF ratio remained unchanged. These observations suggest that, in PLBWI at 1 month, AVN conduction was not predominatly influenced by respiratory-related vagal activity, but was controlled by autonomic regulation, independent of the SAN.  相似文献   
83.
Doppler echocardiographic studies were performed in 14 patients with dual chamber pacemakers. Transmitral flow studies (12 patients) revealed absence of mitral regurgitation (MR) or no change in MR severity in 6, new development or increased MR during VVI and/or short or long A V interval lengths compared to more normal AVintervals(150–160 ms) in 5, and appearance of MR when the pacing mode was changed from VVI to DVI with a fixed AV interval of 250 ms in 1 patient. Aortic peak flow velocity measurements (7 patients) showed significant increases in stroke volume(range9 to 25%. mean 19.5%) in all patients with DVI/VDD pacing compared to VVI pacing (4 patients) or to shortest available AV interval (3 patients). Presence of Doppler left atrial systolic flow correlated with evidence of atrial depolarization in all 7 patients in whom high quality 12-lead surface electrocardiograms were obtained. Our preliminary study demonstrates the value of Doppler echocardiography in the “fine tuning” of cardiac pacemaker parameters by assessment of presence, absence, or change in severity of MR, estimation of relative changes in stroke volume, and determination of atrial capture in different pacing modes and at various AV intervals.  相似文献   
84.
Abstract We have reviewed retrospectively 229 patients interviewed by the mental health team in the Hachijojima since the establishment of our services in 1987. The 6 year observation period was classified into three chronological stages for the purposes of identifying any change in the utilization pattern of the mental health services of the island. The rate of schizophrenia was observed to have decreased from 48% in the first 2 years of the study period to 28% in the last 2 years; while that of other mental disorders increased yearly. Interestingly, an increasing number of patients were referred to our services by professionals in areas other than mental health (from 42 to 77%), and patients without any history of psychiatric treatment were more frequently seen (from 36 to 75%) in the later part of the study period. These changes suggest the importance of access to mental health services.  相似文献   
85.
Doppler echocardiographic studies were performed in 14 patients with dual chamber pacemakers. Transmitral flow studies (12 patients) revealed absence of mitral regurgitation (MR) or no change in MR severity in 6, new development or increased MR during VVI and/or short or long A V interval lengths compared to more normal AVintervals(150–160 ms) in 5, and appearance of MR when the pacing mode was changed from VVI to DVI with a fixed AV interval of 250 ms in 1 patient. Aortic peak flow velocity measurements (7 patients) showed significant increases in stroke volume(range9 to 25%. mean 19.5%) in all patients with DVI/VDD pacing compared to VVI pacing (4 patients) or to shortest available AV interval (3 patients). Presence of Doppler left atrial systolic flow correlated with evidence of atrial depolarization in all 7 patients in whom high quality 12-lead surface electrocardiograms were obtained. Our preliminary study demonstrates the value of Doppler echocardiography in the "fine tuning" of cardiac pacemaker parameters by assessment of presence, absence, or change in severity of MR, estimation of relative changes in stroke volume, and determination of atrial capture in different pacing modes and at various AV intervals.  相似文献   
86.
87.
Bactenecin 5 (Bac 5), a cationic antibacterial peptide, contains a repeating region of Arg-Pro-Pro-X (X = hydrophobic residue). To investigate the structure and property of a Pro/Arg-rich region, we synthesized a series of repeating peptides, Ac-(Arg-Pro-Pro-Phe)n-NHCH3 (n = 2, 4, 6, 8 and 10) (PR2, PR4, PR6, PR8 and PR10,) as models. The circular dichroism (CD) study suggested that the peptides with longer repeats, PR6, PR8 and PR10, formed a conformation similar to poly(proline)-II in aqueous solution. The CD spectra did not change in the presence of dipalmitoyl-d -α-phosphatidylcholine (DPPC), but they changed in the presence of DPPC/dipalmitoyl-dl -3-phosphatidylglycerol (DPPG). The γ-helix, which is very similar in conformation to the poly(proline)-II helix, had the lowest energy conformation for the peptides by energy calculations. Peptides PR6, PR8 and PR10 caused slight leakage of fluorescent dye entrapped in DPPC vesicles, and in the presence of DPPCDPPG, these peptides showed a considerable level of dye-leakage activity. In contrast, the shorter peptides PR2 and PR4 showed no activity. The same tendency was found in measurements of membrane-fusion activity. Judging from these results, the repeating region of Bac 5 may make a framework to hold a conformation resembling the poly(proline)-II structure in aqueous solution. In addition, this region may interact with acidic lipids, resulting in a change in conformation of the peptide. © Munksgaard 1998.  相似文献   
88.
Envelopeglycoprotein(Env)ofHIV1isacom plexoftwononcovalentlyassociatedsubunits,Gp120andGp41.Gp120isanexternalsubunit thatbindsthecellularreceptorCD4andachemo kinereceptor,suchasCXCR4orCCR5.Gp41isatransmembranesubunit,responsibleforthere ceptor mediatedmembranefusion[1,2].Because ofthehighvariabilityofHIV1,theaminoacid sequenceaswellasthestructureofviralenvelope canvaryandresultinthechangeofviraltropism withtimeextensionanddiseaseprogressionafter infection.DuringtheearlyphaseofHIVinfec…  相似文献   
89.
The objectives of this study were to characterize the amorphous state of ursodeoxycholic acid (UDCA) samples prepared by spray-drying, and to demonstrate the applicability of thermal and water-vapour-adsorption techniques for studying the material. Amorphous UDCA was prepared by spray-drying a solution of the compound in a mixture of ethanol and dichloromethane. The amorphous material was characterized by powder X-ray diffraction, infrared (IR) spectroscopy, isothermal microcalorimetry, differential scanning calorimetry (DSC) and water-vapour adsorption. When the inlet-air temperature of the spray drier was increased beyond 140°C, the intensity of X-ray diffraction peaks from crystalline UDCA decreased and the IR bands in the hydroxyl-stretching and carboxyl-stretching regions changed. Dissolution of intact and spray-dried samples of UDCA prepared at 60 and 100°C was an endothermic process but the dissolution became exothermic with increasing inlet-air temperature. UDCA samples differing in crystallinity were obtained, depending on the inlet-air temperature. A good correlation was obtained between the heat of solution and the heat of crystallization determined from DSC peak area. A good correlation was also obtained between the heat of solution and the crystallinity determined by Ruland's method from X-ray diffraction patterns. The amount of water vapour adsorbed on UDCA samples increased with increasing inlet-air temperature, indicating hydrogen bonding between water molecules and the hydroxyl groups or the carboxyl groups of amorphous UDCA. These results indicate that measurement of adsorption of water vapour and thermal analysis can both be used to evaluate the crystallinity of solid substances.  相似文献   
90.
Alveolar soft-part sarcoma of the retroperitoneum   总被引:3,自引:0,他引:3  
A 33-year-old woman was referred to Iida Municipal Hospital because of left back pain. Computed tomography showed a tumor (17 x 11 x 10 cm) in the left retroperitoneal space. T1- and T2-weighted magnetic resonance imaging showed an inhomogeneous mass with marginal blood vessels. The tumor was resected via lumbar oblique incision with the thoraco-abdominal approach. The tumor weighed 1800 g and consisted of nests of 5-100 large, loosely arranged, polygonal cells, surrounded by capillaries, resembling alveoli. The tumor cells were rich in cytoplasm, containing periodic acid-Schiff- and diastase-positive granules and typical crystals. The pathological diagnosis was alveolar soft-part sarcoma (ASPS). Alveolar soft-part sarcoma is a rare soft-tissue tumor that accounts for approximately 0.5-1% of soft-tissue sarcomas. Such tumors originating in the retroperitoneal space are extremely rare. Herein is reported a case of ASPS of the retroperitoneum with radiological and pathological findings.  相似文献   
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