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41.
Recent studies have shown that angiogenesis-stimulatory factors exist in ocular tissues and play a crucial role in the development of some eye disorders such as diabetic retinopathy. However, there are few reports that studied location of angiogenesis factors in ocular tissues of experimental animals. We studied angiogenesis factors in ocular tissues of normal rabbits by chorioallantoic membrane (CAM) assay. Extracts derived from the retina, iris-ciliary body and optic nerve showed an evident activity of angiogenesis. Retinal extracts at 10 micrograms showed a strong angiogenic activity in 50% of CAMs (p less than 0.01). On the other hand, bovine serum albumin which is heterogeneous protein showed only a slight angiogenic activity at a high concentration (1,000 micrograms). The iris-ciliary body and optic nerve showed also an angiogenic activity as did the retina. Extracts from the heart, liver and serum showed no activity of angiogenesis. Thus, angiogenic activity was strongly present in the ocular tissues, especially in retina of the normal rabbits.  相似文献   
42.
201Tl myocardial SPECT was performed in cases of dilated cardiomyopathy and valvular heart disease with left ventricular eccentric hypertrophy, and the two groups were compared from the standpoint of the mechanism of onset of myocardial disorders. Significant coefficients of correlation were seen between the Tl score and LVDd (r = 0.792, r = 0.785) and Tl score and LVEF (r = -0.634, r = -0.555) in both dilated cardiomyopathy and valvular heart disease. In cases of valvular heart disease, significant correlation coefficients (r = -0.756, r = -0.720) between LVDd and r-WR (relative-washout rate), and Tl score and r-WR were observed, but no such correlation was seen in dilated cardiomyopathy. In valvular heart disease, a decrease in myocardial perfusion associated with enlargement of the left ventricle appeared, while in dilated cardiomyopathy, there was a marked decrease in LVEF in proportion to the thallium defect. Therefore, it was assumed that left ventricular wall disorders occur due to myocardial metabolic disorders and coronary microcirculation disorders.  相似文献   
43.
A 47-y-o man had been suffering from cardiac failure due to refractory ventricular tachycardia (VT) after myocardial infarction. He underwent resection of the left ventricular aneurysm and cryocoagulation of the arrhythmogenic foci. On the 2nd post-operative day, VT often recurred in spite of repeated cardioversion and drug therapy, and threatened his life, even under IABP. Therefore, a veno-arterial bypass route was made and extracorporeal lung and heart assist, ECLHA, was started with a heparin bonded Maxima lung on the following day. Even under ECLHA, VT continued to recur. Cryocoagulation of the VT foci was tried again, without immediate success. A record high dose of beta-blockers, given under the circulatory support by ECLHA, stopped VT on the following day. The patient was weaned from the ECLHA circuit 12 days after the first operation, then from IABP on the 14th day. During the 10 day course of surgeries and ECLHA, the patient had almost 100 defibrillations. But for ECLHA, we may say that the patient couldn't have survived two open heart surgeries, administration of a great amount of beta-blockers, and repeated cardiac arrest without neurological sequelae.  相似文献   
44.
To investigate the role of glucose in regulating glucose transporters in pancreatic beta-cells, we studied the hamster clonal beta-cell line HIT-T15, which retains responsiveness to glucose. Northern blot analysis demonstrates that GLUT2 and GLUT1 mRNA are abundant in HIT cells. After a 24-h culture with various concentrations of glucose (0-22.2 mM [0-400 mg/dl]), the GLUT2 mRNA level in HIT cells increased by 40% at 22.2 mM (400 mg/dl) glucose compared with 11.1 mM (200 mg/dl) without a change in mRNA stability. It also decreased proportionally to the reduction of glucose concentration. Glucose deprivation resulted in a decrease of GLUT2 mRNA to an almost undetectable level, with a marked increase in the degradation rate of mRNA. In contrast, the GLUT1 mRNA was not affected by glucose. We show that glucose uptake is highest in HIT cells incubated at 2.8-5.5 mM (50-99 mg/dl) glucose for 24 h, and that levels in cells cultured at 0 mM (0 mg/dl) and 22.2 mM (400 mg/dl) glucose decrease to approximately 20% of the maximum level. This decrease is consistent with the effects of glucose on glucose-stimulated insulin secretion in HIT cells. Our results indicate that glucose is involved in regulating GLUT2 mRNA and glucose uptake activity and that the glucose responsiveness of the insulin secretion correlates with the glucose-induced change in glucose uptake activity in HIT cells.  相似文献   
45.
The objective of this study is to develop a sensitive temperature-responsive material that would function near body temperature. To achieve this purpose, we compounded 2-branched and 4-branched poly(epsilon-caprolactone) macromonomers to modulate the transition temperatures of the resulting cross-linked materials. The temperature-responsive properties were studied using differential scanning calorimetry and X-ray diffraction measurements. As a result, the mixing ratios of each macromonomer or the total macromonomer concentrations were very dominant in modulating the transition temperatures. The materials could successfully control the permeation of the model drug, prednisolone, near body temperature.  相似文献   
46.
A patient with cerebral deep sinus thrombosis, which was not diagnosed on the first examination, is reported. A 46-year-old woman presented with headache and vomiting. Neurological examination and a brain computed tomography (CT) scan showed no obvious abnormal findings. The patient suffered disturbed consciousness on the day after the examination, and was admitted to our emergency centre. A CT scan and magnetic resonance imaging revealed an ischaemic lesion in the left basal ganglia, suggesting deep sinus occlusion. Anticoagulant therapy was administered. One day after admission, a CT scan showed a haematoma and severe brain swelling in the same region. Cerebral angiography demonstrated a straight sinus occlusion. Intracranial pressure was not controlled with hypothermia, and the patient died 25 days after admission. Review of the initial CT scan revealed subtle, early findings of deep venous thrombosis that were missed on first examination.  相似文献   
47.
BACKGROUND: To establish the criteria for selecting a mitral annuloplasty ring of the correct size, the dimensions of the mitral valve orifice were analyzed in cadaveric hearts. MATERIALS AND RESULTS: From December 2000 to July 2006, the mitral valve diameter [DM (Obs)] and Z-values [DM (Z); standardized value based on Rowlatt's criteria], the angles of the trigones (theta Tg) and commissures (theta Com) and the intertrigonal distance [L (T)] were measured in 82 fresh cadaveric hearts from cases with variable causes of death (mean age 64.8+/-15.7 years; body surface area [BSA] 1.51+/-0.21 m2). DM (Obs), DM (Z) and L (T) were 2.8+/-0.5 cm, 1.16+/-0.98, and 1.8+/-0.2 cm, respectively. Theta Tg and theta Com averaged 76+/-13 and 121+/-11 degrees, respectively. There was a significant inverse linear relationship between DM (Z) and theta Tg [theta Tg =-10x DM (Z) +88] and a significant logarithmic correlation between L (T) and BSA [L (T) =0.54xLn (BSA) +1.55]. The anterior annular length and L (T) remained unchanged. CONCLUSION: In non-dilated cadaveric hearts, the trigones were located at one-quarter of the mitral annulus, so the appropriate length of the posterior annuloplasty band should be adjusted to L (T) x3.33.  相似文献   
48.
A 78-year-old woman was admitted with dyspnea. She had caught a cold and took an over-the-counter drug (Nospole G) for 2 weeks before admission. Chest radiography and CT scanning showed bilateral diffuse and interstitial shadows, and arterial blood gas analysis demonstrated severe hypoxemia. Withdrawal of Nospole and treatment with both corticosteroid and sivelestat sodium resulted in improvement of clinical findings and successful recovery from mechanical ventilation. A drug lymphocyte stimulation test for Nospole G was positive. Based on these findings, we determined that this patient had drug-induced pneumonitis caused by Nospole G. Finally, she died of sepsis caused by multidrug-resistant Staphylococcus aureus (MRSA) infection. In summary, we report here an elderly case of drug-induced pneumonitis successfully weaned from mechanical ventilation by early treatment with corticosteroid and sivelestat sodium, monitored by changes of markers for interstitial pneumonitis (KL-6, SP-A, SP-D).  相似文献   
49.
Langerhans cell histiocytosis is currently regarded as a reactive proliferative process of Langerhans cells rather than a malignancy. The disease is characterized by Langerhans cell infiltration of skin, lung, bone and other organs. We report a 74-year-old man with Langerhans cell histiocytosis who had generalized hemorrhagic and crusted papules. He also had diabetes insipidus. Because he did not have any severe constitutional symptoms or failure of vital organs, we applied topical PUVA treatment to his skin lesions, which responded well to the therapy. Diabetes insipidus, however, remained, in spite of X ray radiotherapy for the pituiary lesion.  相似文献   
50.
A 70-year-old man was admitted to our hospital because of fever and progressive dyspnea in December 1989. He was already diagnosed as having erythrocytosis secondary to pulmonary fibrosis 4 years previously and the values of his hematocrit (Ht) were maintained between 44.5 and 62.9% by repeated phlebotomy. Immediately after admission, severe diarrhea developed and the Ht value was 61.5%. Around 1:30 a.m. of the 3rd hospital day, he developed disturbance of consciousness. In addition, the serum levels of LDH, CPK, aldolase, and myoglobin of muscle origin increased markedly and the Ht value showed 78.5%. While the level of consciousness was gradually restored by 600 ml phlebotomy and 1,500 ml saline infusion, dysarthria and hemiplegia became evident. The Ht value early in the morning of the 3rd hospital day was reduced to 59.4%. Although cranial CT and MRI performed 74 days and 15 months, respectively, after the onset of the symptoms failed to reveal any abnormal shadow, he was clinically suspected to have cerebral infarction. These findings emphasize that abrupt increase in Ht or blood viscosity is a possible factor triggering cerebral infarction, and adequate control of Ht value is recommended for the prevention of such a condition in the aged.  相似文献   
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