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91.
A 48-year-old man presented with malignant hypertension and massive proteinuria. Renal angiography showed complete obstruction of the left renal artery and 99mTc-mercaptoacetylglycine (MAG3) renography showed a nonfunctioning left kidney. Percutaneous transluminal renal angioplasty of the left renal artery was unsuccessful; hence, the patient underwent left nephrectomy because of uncontrolled hypertension and proteinuria. Histological examination of a right kidney specimen revealed lesions of focal segmental glomerulosclerosis with benign nephrosclerosis. In contrast, histology of the left kidney showed typical ischemic kidney with hypertrophy of arteriolar smooth muscle cells. The patient responded favorably to the nephrectomy, as his blood pressure and urinary protein dramatically decreased with no antihypertensive medication. This case illustrates the heterogeneous effect of the renin-angiotensin system on either kidney in patients with renovascular hypertension due to unilateral renal artery stenosis.  相似文献   
92.
Summary We observed a rare cerebrovascular anomaly in a patient with brain-stem infarction. Two right vertebral arteries arose from the subclavian artery and communicated directly with each other under the transverse foramen of the fourth cervical vertebra. The left vertebral artery consisted of a rudimentary artery that arose from the left subclavian artery, ran through the transverse foramen of the sixth cervical vertebra and then tapered down to disappear at the fourth/fifth cervical vertebrae, plus a second, accessory artery that arose from a branch of the left thyrocervical trunk, ran through the transverse foramen of the fifth cervical vertebra and tapered off to disappear at the first/second cervical vertebrae.  相似文献   
93.
The production of tumor necrosis factor alpha (TNF alpha), interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) by stimulated peripheral blood monocytes/macrophages (PBM) was assessed in patients with multiple sclerosis (MS), other neurological diseases (OND) or normal controls (NC) using enzyme-linked immunosorbent assay (ELISA). PBM obtained from acute phase of MS produced significantly higher amount of all these cytokines than those from chronic stable MS, OND or NC (TNF alpha, IL-1 alpha, IL-6: p less than 0.01, IL-1 beta: p less than 0.05). Methylprednisolone (MP) inhibited the lipopolysaccharide-induced cytokine production in a dose-dependent manner. These results suggest the possible roles of activated monocytes/macrophages in the acute exacervation of MS and suppressive effect of MP on cytokine production by activated monocytes/macrophages.  相似文献   
94.
The proliferative activity of gastric cancer cells with endocrine features was evaluated in five cases by means of a double-immunostaining procedure. The endocrine cells were recognized by a monoclonal antibody to chromogranin A (CGA) and the proliferative activity by a monoclonal antibody to proliferating cell nuclear antigen (PCNA). With the use of two different chromogens it was easy to determine whether CGA was located in the cytoplasm and whether PCNA was located in the nucleus of the same section. The CGA-positive endocrine cells of the normal gastric antral mucosa could be readily distinguished from the PCNA-positive cells scattered in the mucosal neck zones. Over 1,000 CGA-positive cancer cells were counted per case. A few cells (average, less than 1.0%) exhibited faint nuclear staining with anti-PCNA; in no instance was unequivocal PCNA reactivity demonstrable in the gastric cancer cells with endocrine differentiation. By contrast, the PCNA reaction was positive in one fourth to one third of the other cancer cells. These observations suggest that gastric cancer cells with endocrine features are differentiated and do not participate in the cell cycle.  相似文献   
95.
Summary Changes in tumour blood flow under an induced hypertensive state were examined in malignant brain tumours to know if the precondition for the effectiveness of induced hypertensive chemotherapy — relative increase in tumour blood flow — are fulfilled. Tumour blood flow was measured under both a resting and an induced hypertensive state in 12 patients with various malignant brain tumours (6 gliomas, 6 metastatic brain tumours) using xenon-enhanced computed tomography. The blood pressure was elevated 40% above the systemic blood pressure of the resting state by the infusion of angiotensin II. Tumour blood flow increased 30% on average above the normal brain tissue blood flow after the induction of an induced hypertensive state (p < 0.05). The tumour blood flow increased in 11 cases of malignant tumours, but decreased in one case with massive brain oedema after induced hypertension. The increase in blood flow was higher in hypervascular tumours and less in hypovascular tumours. Therefore, induced hypertensive chemotherapy probably will be more effective in hypervascular malignant brain tumours with small mass effects.  相似文献   
96.
The biochemical activity of cepharanthine and the possible mechanism by which it reverses the resistance to doxorubicin in P388 leukemia cells were examined in vitro. The microfluorometric analysis of the cellular level of doxorubicin in drug-resistant cells showed that cepharanthine markedly enhanced the sensitivity of doxorubicin against resistant cells in the cellular level. Cepharanthine also enhanced the inhibitory effect of doxorubicin on the incorporation of thymidine into DNA in resistant cells. The analysis of DNA histogram obtained by flow cytometry showed that doxorubicin exerted its growth-inhibitory effect by blocking the cell cycle at the G2 phase in P388 cells. At higher concentrations, doxorubicin prolonged the S phase and inhibited cell cycle progression to the G2/M phase in cells. The treatment with cepharanthine potentiated these blocking effects induced by doxorubicin in cells. It seems that the modifications of the biological effect of doxorubicin by cepharanthine are due to the change of their ability to induce DNA damage in cells.  相似文献   
97.
Effects of urine pH on the renal tubular secretion of an organic cation (tetraethylammonium, TEA) and an organic anion (p-aminohippurate, PAH) were investigated using the isolated erythrocyte-perfused rat kidney. The method was based on a multiple indicator dilution experiment and noncompartmental moment analysis. Treatment with sodium bicarbonate and sodium dihydrogen phosphate increased and decreased urine pH, respectively, but affected neither the condition of the perfused kidney nor the renal handling of albumin and inulin. In TEA studies, the increase of urine pH prolonged the mean residence time in renal epithelial cells (T cell) and reduced the apparent secretion intrinsic clearance, but did not influence the volume of distribution in the kidney (Vd drug). The decrease of urine pH did not affect these kinetic parameters. By contrast, PAH secretion was constant against the change of urine pH. Since any change in the basolateral membrane transport is reflected in Vd drug, the net transport from blood to cells can be regarded as similar under these treatments. On the other hand, the prolonged T cell of TEA with the increased urine pH suggested a slow transport from cells to lumen across the brush-border membranes. The present results coincide with the hypothetical mechanism that organic cations are secreted via an active transport system, coupled to the countertransport of H+ into cells. In conclusion, the present method is useful to separately evaluate the transmembrane transport across both sides of the renal epithelial cells in a morphologically intact kidney.  相似文献   
98.
The lactic dehydrogenase (LDH) level in plasma and the clearance of LDH in C.B-17 scid (severe combined immunodeficiency; SCID) mice were compared with those in C.B-17 or BALB/cCrSlc mice with or without lactic dehydrogenase virus (LDV) infection. The resting enzyme level in SCID mice showed little difference from that in C.B-17 or BALB/cCrSlc mice. The degree of increased plasma LDH level in SCID mice was lower than that in C.B-17 and BALB/cCrSlc mice after LDV infection. To assess the mechanisms of decrease in LDH elevation in SCID mice infected with LDV, virus replication was compared in SCID and BALB/cCrSlc mice. The infectivity titre of plasma in SCID mice was higher (more than 10 times) than that in BALB/cCrSlc mice. Moreover, the percentage of virus antigen positive Kupffer cells was higher in SCID mice than that in BALB/cCrSlc mice. The level of endogenous LDH release as a result of carbon tetrachloride treatment was similar in the SCID and BALB/cCrSlc mice. The clearance rate of endogenous LDH was greater in SCID mice than in BALB/cCrSlc mice with or without LDV infection. The rate of clearance of intravenously injected porcine LDH-5, but not porcine LDH-1, was enhanced in SCID mice as compared with that in BALB/cCrSlc mice. Furthermore, carbon clearance was higher in SCID mice than that in BALB/cCrSlc mice. These results suggest that the smaller increase of plasma LDH after infection might be due, at least in part, to the enhanced LDH-5 clearance function by macrophages in SCID mice.  相似文献   
99.
In 29 cases undergoing lung resection, effects of the surgery on left ventricular function were investigated indirectly with a Nuclear Stethoscope. Various parameters were measured following an exercise load before and after surgery. There were significant decreases in post-operative resting levels of stroke volume (SV) (p < 0.001), end-diastolic volume (EDV) (p < 0.001), ejection fraction (EF) (p < 0.05) and ejection rate (ER) (p < 0.001) and significant increase in heart rate (HR) (p < 0.001) when compared to pre-operative resting levels. Neither filling rate (FR) nor cardiac output (CO) showed significant difference. At maximum exercise load, there were significant decreases in post-operative EDV (p < 0.005), SV (p < 0.005), ER (p < 0.001) and FR (p < 0.005), but no significant differences were detected in HR and EF; consequently, there was a significant decrease in CO (p < 0.005). Ratio of the levels at maximum load to those at resting of each parameter did not show significant difference between before and after operation with regard to any parameters except CO and FR which showed significant decrease (p < 0.005 and p < 0.001, respectively). Effects of the surgery on left ventricular function were studied according to amount of lung resection. In 13 cases where more than two lobes were resected, similar significant differences to those mentioned above were found in all parameters except EF. In cases where a single lobe was resected, only ER and FR showed similar tendency to that described above. Effects of the surgery on left ventricular function were also studied according to age of patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
The diuretic and the antihypertensive actions of torasemide were examined in renal and genetic hypertensive rats and compared to the effects of furosemide. Oral administration of torasemide (1 and 3 mg/kg) elicited a dose-dependent increase in the excretion of urine and electrolytes and elevated the urinary Na/K ratio in both renal and genetic hypertensive rats. Torasemide and furosemide had a similar maximum diuretic effect in the normotensive Wistar rat and the spontaneously hypertensive rat (SHR). However, the diuretic activity of furosemide was weaker in the renal hypertensive rat (RHR). Torasemide showed approximately 30 times greater diuretic potency than furosemide. Torasemide and furosemide demonstrated hypotensive action in hypertensive rat models, but not in the normotensive Wistar rat. Especially in the RHR, torasemide exhibited a more potent hypotensive action than furosemide. These results show that the diuretic and antihypertensive activities of torasemide are effective in various rat models of hypertension, while the diuretic activity of furosemide is weak in certain hypertensive rat models. © 1992 Wiley-Liss, Inc.  相似文献   
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