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51.
OBJECTIVE: To clarify the position of on-pump beating coronary artery bypass (CAB) and to define preoperative indicators of intentional conversion to the procedure in the era of advancement of off-pump CAB (OPCAB), we assessed on-pump beating CAB performed after the introduction of OPCAB. SUBJECTS AND METHODS: We assessed 130 patients who underwent single CAB [117 (90%) with OPCAB and 13 (10%) with on-pump beating CAB] between August 1999 (when OPCAB was selected as the first-line surgical procedure) and December 2004. RESULTS: No significant differences were seen between the groups in the number of coronary lesions or the prevalence of left main trunk (LMT) lesion. Reduced left cardiac function, cardiac dilatation, and mitral regurgitation (MR) were more remarkable in the on-pump beating CAB group. Preoperative ischemic condition was generally unstable in the both groups. A conversion to on-pump beating CAB occurred at anastomosis for the left anterior descending (LAD) branch in 61% and for the left circumflex (LCX) branch in 15%. LAD patients had more severe left cardiac dysfunction and cardiac dilatation than LCX patients. CONCLUSION: To perform safe and reliable CAB surgery, cardiovascular surgeons should define preoperative indicators of difficult OPCAB and convert OPCAB to on-pump beating CAB intentionally without hesitation when unstable hemodynamics is detected.  相似文献   
52.
An increase of chlordane contamination in humans after termite treatment of their homes was investigated by analyzing human milk samples of breast-feeding women. Chlordane in human milk was analyzed by gas chromatography-mass spectrometry (GC-MS) and the concentrations were compared between women living in termite-treated and non-treated houses. Polychlorinated biphenyls (PCB) were also analyzed on the same samples and the result was discussed in relation to the concentration of chlordane.Mean concentrations of six chlordane components of the exposed group were three times higher on the average than those of the control group. When the duration of dwelling was less than one year, however, chlordane levels of the treated group were similar to those of the control.A proportional correlation was observed between the concentration of total chlordane and the duration (years) after the termite treatment of the home. The pattern of chlordane components observed in the milk of the exposed group resembled that of technical chlordane, a commercial product. Chlordane compounds were so stable and persistent in the treated homes that continuous accumulation into the dwellers persisted for at least five years after treatment.The levels of total chlordane in the milk samples of the control group were very low compared to PCB levels. However, when duration of dwelling after termite treatment expanded for two years or longer, chlordane in the milk increased to a level similar to PCB.A close correlation between concentrations of chlordane and PCB of the non-treated group was observed. This fact suggested that a main source of chlordane exposure for the general population was marine products. However, in the case of the treated group, chlordane exposure was inferred to be derived from the inhalation of a contaminated atmosphere in the homes or absorption of chlordane via the skin or uptake of foods contaminated in the homes.  相似文献   
53.
Five mg/kg imipramine or desipramine was injected to infantile rats. L-5-Hydroxytryptophan-induced head shakes were assessed when rats were mature. The saline- and desipramine-treated adult male rats exhibited more sustained response to L-5-HTP than females. The time course of the head shake frequency in the imipramine-treated male and female rats showed a pattern between control males and females, resulting in no significant sex difference. The results suggest that infantile exposure to imipramine induces an alteration of the serotonergic neurons of the brain.  相似文献   
54.
K Taguchi  Y Suzuki 《Brain research》1992,583(1-2):150-154
The effects of cutaneous noxious heating and of systemic morphine on serotonergic activity in the spinal cord were examined in anesthetized rats. An oxidation current of 5-hydroxyindole signal was seen at 280-300 mV with differential normal pulse voltammetry. Noxious heat stimuli produced a mean signal increase over control values of 15.5 +/- 3.4% at 52 degrees C, and 7.2 +/- 5.5% at 45 degrees C. These increases lasted for 5-10 min. Non-noxious stimuli (37 degrees C) did not affect the 5-hydroxyindole signal. Morphine (0.5, 2.0 and 5.0 mg/kg, i.p.) in the absence of cutaneous stimulation did not change the signal significantly. Systemic morphine alone did not significantly modify the 5-hydroxytryptamine (5-HT) metabolism, as observed in in vivo voltammetry, in the spinal cord of anesthetized rat. However, a low dose of morphine (0.5 mg/kg, i.p.) attenuated the increase in the signal modified by noxious stimuli, and high doses (2.0 or 5.0 mg/kg, i.p.) enhanced it. Both effects of morphine were antagonized by naloxone (0.5 mg/kg, i.v.). It is likely that morphine with noxious stimuli modify the sensitivity of serotonergic descending inhibitory system. It is concluded that noxious heating of the skin increases the 5-HT metabolism in the spinal cord of anesthetized rats and that systemic administration of morphine modulates this 5-HT metabolism.  相似文献   
55.
W Hida  S Okabe  H Miki  Y Kikuchi  O Taguchi  T Takishima    K Shirato 《Thorax》1994,49(5):446-452
BACKGROUND--It has previously been reported that short term submental stimulation can reduce the frequency of apnoea and improve sleep architecture in patients with obstructive sleep apnoea. The effects of submental stimulation during consecutive nights on apnoea or on daytime sleepiness have not, however, been studied. METHODS--Patients with obstructive sleep apnoea were studied by polysomnography on a control night, for five consecutive nights of submental stimulation, and on three following nights (n = 8). A multiple sleep latency test (MSLT) (n = 8) and measurement of the upper airway resistance (n = 5) were performed during the day after the polysomnographic study, on the control night, and on the fifth stimulation night. In an additional five patients with obstructive sleep apnoea, matched for age, sex, and weight, the effects of two nights of stimulation were examined for comparison. Submental stimulation began when an apnoea lasted for five seconds and stopped with the resumption of breathing as detected by oronasal flow. RESULTS--The apnoea index, the number of times per hour that SaO2 dropped below 85% (SaO2 < 85%/hour), and the total apnoea duration expressed as a percentage of total sleep time during stimulation nights decreased to approximately 50% of the corresponding values on the control night. This improvement persisted for at least two nights after the five consecutive stimulation nights, but not after the two consecutive stimulation nights. Sleep architecture and MSLT following the stimulation nights improved but upper airway resistance did not change. CONCLUSIONS--Submental stimulation for five consecutive nights in patients with obstructive sleep apnoea improved the breathing disturbance, sleep quality, and daytime sleepiness. The effect lasted for the following two nights, but did not completely abolish the sleep disordered breathing.  相似文献   
56.
Enhancement of the antitumor effects of adriamycin (ADR) by concomitant use of degradable starch microspheres (DSM) and pharmacokinetics of ADR in combination with DSM was investigated. An intra-arterial chemotherapy model of the nude rats transplanted of human gastric cancer xenografts (H-154) in the hind-limbs was used for this study. Drug was administered through a catheter inserted into the carotid artery with the tip in the common iliac artery. In the pharmacological study, increase of regional uptake of ADR and decrease of systemic distribution of ADR were recognized in some degree. DSM 30 mg/kg, which caused temporary arrest of blood flow in the tumor, had an only weak effect on tumor growth. ADR 3 mg/kg mixed with DSM 30 mg/kg was more effective than ADR 3 mg/kg solution. Furthermore, mixture of ADR 2 mg/kg and DSM 30 mg/kg had a greater effect on tumor growth than ADR 2 mg/kg following DSM 30 mg/kg. It seems that embolization by DSM, retention of ADR in regional tissues and cytotoxic effect of ADR have contributed to such a strong effect of ADR mixed with DSM.  相似文献   
57.
A case of serous cystadenoma of the pancreas with focal malignant changes   总被引:3,自引:0,他引:3  
Summary We present a serous cystadenoma of the pancreas with focal malignant changes, and describe its characteristic histological features. On gross examination, a tumor was present on the anterior surface of the body of the pancreas and measured approx 25×25⋻20, mm. Microscopically, most tumor cells showed the typical histological features of serous cystadenoma, characterized by a microcystic architecture and glycogenrich cells with a uniform and bland appearance. However, in some areas, a tendency to papillary structures with fibrovascular cores was noted. These papillary lesions were composed mainly of nonmucinous, glycogen-poor epithelial cells, the nuclei of which showed a mild atypia. In addition, vascular and perivascular invasion was focally observed. However, there was no clinical evidence of local or distant metastasis. From these findings, we diagnosed this lesion as a serous cystadenoma of the pancreas with focal malignant changes rather than a serous cystadenocarcinoma of the pancreas.  相似文献   
58.
Primary squamous cell carcinoma of the submandibular gland is a rare tumor. In this report, the histological and ultrastructural features of a case of primary squamous cell carcinoma arising in the left submandibular gland is presented. Light microscopically, the tumor consisted of well differentiated keratinizing squamous cell nests. Ultrastructurally, the tumor cells were oval or spindle-shaped, and several tumor cells had intracytoplasmic desmosome-like structures, resembling intercellular desmosomes. The majority of the tumor cells contained a large number of intermediate filaments (tonofilaments). Intercellular desmosomes were well developed. No secretory granules were found. These ultrastructural features may enable us to distinguish primary squamous cell carcinoma from mucoepidermoid carcinoma which is often misdiagnosed as squamous cell carcinoma.  相似文献   
59.
A 17-year-old girl developed vomiting of sudden onset, followed by a state of confusion that progressed rapidly to coma within one day. Laboratory tests indicated iron deficiency anemia and reactive thrombocytosis, but there was no evidence of coagulopathy. There was no history of medication including the contraceptive pill, either. Emergency CT scan without contrast enhancement showed increased density along the course of the vein of Galen and internal cerebral veins. A repeated CT scan without contrast enhancement carried out 24 hours after the onset of the illness confirmed extensive bilateral hypodensity of the thalami, basal ganglia and adjacent white matter. There was also a prominent spontaneous increase in the density of the deep cerebral venous system. MRI was performed 3 days after the onset of the illness, which showed absence of a flow void in the region of the internal cerebral veins and septal veins on T1-weighed images. T2-weighted images showed low intensity in these veins. At autopsy, the bilateral internal cerebral veins were occluded by fresh thrombosis and hemorrhagic infarction was seen in the bilateral thalami.  相似文献   
60.
CA 125 is an antigen associated with non-mucinous epithelial ovarian cancer, which is defined by OC 125 antibody developed by immunizing ovarian cancer cells. We have produced two monoclonal antibodies, 130-22 and 145-9, by using the human lung adenocarcinoma cell line PC-9. Both 130-22 and 145-9 antibodies recognized CA 125 antigen. However, the binding sites seemed to be separate from those of OC 125. Testing by 9 immunoradiometric assays (IRMA), using different combinations of the 3 monoclonal antibodies 130-22, 145-9 and OC 125 demonstrated that the best standard curve for detecting CA 125 could be obtained by a "simultaneous sandwich" assay based on a mixture of 125I-labeled OC 125 and 130-22 or 145-9 coated beads. One-step IRMA, using 130-22 as a tracer and 145-9 as an immunoadsorbent, also showed good reproducibility and sensitivity for measuring CA 125. Antigens were detectable in the culture supernatants of PC-9 cells and 5 of 6 ovarian cancer and endometrial adenocarcinoma cells. These results indicate that one-step IRMA using 130-22 and 145-9 is useful for detecting CA 125 antigen.  相似文献   
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