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71.
72.
We investigated the wetting transitions of tetradecane and hexadecane droplets in dodecyltrimethylammonium bromide (C12TAB), tetradecyltrimethylammonium bromide (C14TAB), and hexadecyltrimethylammonium bromide (C16TAB) aqueous solutions. By varying the surfactant concentration, the formation of mixed monolayers of a surfactant and an alkane was observed at the air–water interface. Depending on the combination of surfactant and alkane, these wetting monolayers underwent another thermal phase transition upon cooling either to a frozen mixed monolayer (S1) or a bilayer structure composed of a solid monolayer of a pure alkane rested on a liquid-like mixed monolayer (S2). Based on the phase diagrams determined by phase modulation ellipsometry, the difference in the morphology of the nucleated S1 and S2 phase domains was also investigated using Brewster angle microscopy. Domains of the S1 phase were relatively small and highly branched, whereas those of the S2 phase were large and circular. The difference in domain morphology was explained by the competition of the domain line tension and electrostatic dipole interactions between surfactant molecules in the domains.  相似文献   
73.
There are few case reports of hepatocellular carcinoma (HCC) metastasis to the skeletal muscle. A 78-year-old man developed a mass in the right shoulder. Washout of contrast medium during contrast-enhanced ultrasonography (CEUS) in both the primary HCC and the metastatic site was detected. Several nodules were scattered throughout the liver on an autopsy. In addition, the moderately differentiated HCC had metastasized to the right teres major muscle. Rare muscular metastasis should be considered if a hepatic tumor is moderately or poorly differentiated HCC. Early washout during CEUS is consistent with a pathological diagnosis of moderately or poorly differentiated HCC.  相似文献   
74.
Frequency of Treponema pallidum invasion into cerebrospinal fluid (CSF) has not been clear at this present. Since it is impossible to culture T. pallidum in vitro at this present, we need molecular based-approach to detect it in CSF. Additionally, neurosyphilis is usually a late sequela, however it might result in asymptomatic neurosyphilis even at primary or secondary syphilis. This study was to reveal the frequency of T. pallidum invasion into CSF especially at primary or secondary syphilis with polymerase chain reaction (PCR) test.All patients were visited the Aichi Medical University Hospital or Izumi ladies' clinic between 2016 and 2017. Clinical CSF samples were collected from patients with early and late stages of syphilis. The PCR was done using primers targeting the tpN47gene.CSF samples were collected from 9 patients (4 patients with primary syphilis, 3 with secondary syphilis, and 1 early latent syphilis and 1 with late latent syphilis). PCR showed positive reaction in 2 of 7 (28.6%) primary and secondary syphilis patients, in 1 of 1 (100%) early latent syphilis patients, and in 1 of 1 (100%) late latent syphilis patients.Despite its lack of sensitivity for use alone as a diagnostic test, this PCR test should be preferred for the diagnosis of neurosyphilis. Because, T. pallidum was detected in the 28.6% CSF of patients at primary and secondary syphilis, which indicated that they invade the central nervous system from the early stages of infection. However, studies in a larger population are required to confirm these preliminary results.  相似文献   
75.
We developed a novel endurance test system that can arbitrarily set various circulatory conditions and has durability and stability for long-term continuous evaluation of ventricular assist devices (VADs), and we evaluated its fundamental performance and prolonged durability and stability. The circulation circuit of the present endurance test system consisted of a pulsatile pump with a small closed chamber (SCC), a closed chamber, a reservoir and an electromagnetic proportional valve. Two duckbill valves were mounted in the inlet and outlet of the pulsatile pump. The features of the circulation circuit are as follows: (1) the components of the circulation circuit consist of optimized industrial devices, giving durability; (2) the pulsatile pump can change the heart rate and stroke length (SL), as well as its compliance using the SCC. Therefore, the endurance test system can quantitatively reproduce various circulatory conditions. The range of reproducible circulatory conditions in the endurance test circuit was examined in terms of fundamental performance. Additionally, continuous operation for 6 months was performed in order to evaluate the durability and stability. The circulation circuit was able to set up a wide range of pressure and total flow conditions using the SCC and adjusting the pulsatile pump SL. The long-term continuous operation test demonstrated that stable, continuous operation for 6 months was possible without leakage or industrial device failure. The newly developed endurance test system demonstrated a wide range of reproducible circulatory conditions, durability and stability, and is a promising approach for evaluating the basic characteristics of VADs.  相似文献   
76.
77.
A 50-year-old woman with a 4-year history of Evans syndrome was admitted to our hospital because of progressive nausea, appetite loss, body weight loss, diarrhea and abdominal pain. Abdominal ultrasonography revealed pleural effusion, ascites, bilateral hydronephrosis, dilatation of the bilateral ureter, and irregular wall thickness of the urinary bladder. Immunological studies revealed decreased complement components (C3; 72 mg/dl, C4; 7 mg/dl, CH50; 28.8 mg/dl), a x 80 antinuclear antibody titer (homogeneous pattern), antibody against single-stranded DNA 19 U/ml, anti-SS-A antibody over 500 U/ml and negativity for antibody against double-stranded DNA (anti-dsDNA Ab). Although the patient did not fulfill the criteria for systemic lupus erythematosus (SLE), we diagnosed her as having lupus cystitis. Bolus methylprednisolone (mPSL) therapy (1,000 mg mPSL over 3 days, div) was administered, followed by 60 mg PSL, and this led to immediate improvement of the patient's symptoms and laboratory data. Later, anti-dsDNA Ab became positive, and the patient thereby fulfilled the criteria for SLE. Lupus cystitis following Evans syndrome has rarely been reported. The present such case was treated successfully with bolus mPSL therapy.  相似文献   
78.
We have reported that infusion of prostaglandin synthesis inhibitor (PGSI) reduced the severity of hypotension during normothermic cardiopulmonary bypass (CPB). In the present study, we investigated the effects of PGSI on humoral conditions and whole body oxygen metabolism during normothermic CPB conducted for 60 min in 8 adult goats. The PGSI group (n = 4) was administered 100 to 150 mg of flurbiprofen, a potent PGSI, before and during CPB, and the control group (n = 4) was administered noradrenaline (NA) to restore hypotension. The prostaglandin E2 (PGE2) and NA concentrations in the PGSI group were significantly lower than those of the control group (PGE2 8.8 +/- 1.0 versus 30.3 +/- 11.5 pg/ml, NA 431 +/- 197 versus 3847 +/- 2,153 pg/ml). The adrenaline concentration was not significantly different between the groups. The oxygen consumption and the oxygen extraction rate were not significantly different between the groups, but the blood lactate level in the PGSI group was lower than that of the control group (34.3 +/- 7.6 versus 43.7 +/- 3.8 mg/dl). In conclusion, PGSI improves humoral disorder and thus prevents inadequate tissue oxygen delivery.  相似文献   
79.
Differentiated thyroid cancer sometimes shows microscopic vascular invasion but rarely causes a tumor thrombus in a great vein. A preoperative diagnosis of the latter condition is difficult if a patient does not have any overt symptoms, but it is important for operative planning. We encountered a 26-year-old woman with papillary thyroid cancer and a tumor thrombus extending from the brachiocephalic vein to the superior vena cava. The tumor was successfully treated by surgical resection. To our knowledge only 19 such cases have so far been reported. We herein report our case, review the literature, and discuss the associated diagnostic problems and treatments including such areas as age, gender, symptoms, pathology, extension, and outcome. Received: October 20, 2000 / Accepted: July 17, 2001  相似文献   
80.
Reactive oxygen     
Mammalian tissues have large amounts of available ATP which are generated by oxidative phosphorylation in mitochondria. To maintain the body, large amounts of oxygen are required to regenerate the ATP molecules. A small fraction of the inspired oxygen is converted to superoxide radicals and related metabolites even under physiological conditions. Most reactive oxygen species react rapidly with a variety of molecules, thereby interfering with cellular functions and various diseases.  相似文献   
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