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101.
Changes in optic nerve head blood flow and retrobular hemodynamics following calcium-channel blocker treatment of normal-tension glaucoma 总被引:2,自引:0,他引:2
Tomita G Niwa Y Shinohara H Hayashi N Yamamoto T Kitazawa Y 《International ophthalmology》1999,23(1):3-10
Background: Because calcium channel blockers reduce vascularresistance, they may have a clinical application in the treatment ofnormal-tension glaucoma (NTG). This study investigates changes inboth the optic disc blood flow and the hemodynamics of retrobulbarvessels in NTG patients after the systemic administration of a calcium channel blocker. Methods: Twelve eyes of 12 NTG patients (meanage 57 6 ± 15.3 years) were examined before and after a 4-weektreatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 × 10 pixel windowplaced on the temporal rim region of the optic disc perfusion map. Byultrasound color Doppler imaging (CDI), we measured the peak systolicvelocity (PSV) and the end diastolic velocity (EDV) of the ophthalmicartery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. Results: After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05).Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA(P <0 .05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. Conclusions: Oral nilvadipine appears to reduce orbital vascular resistance, which consequentlyincreases the optic disc blood flow.
Abbreviations.BP – blood pressure;CRA – central retinal artery;CDI – ultrasound color Doppler imaging;EDV – end diastolic velocity;NPCA – short posterior ciliary arteries located nasal to optic nerve;NTG – normal-tension glaucoma;OA – ophthalmic artery;PP – perfusion pressure;PSV – peak systolic velocity;RI – resistance index;SLDF scanning laser-Doppler flowmetry;TPCA – short posterior ciliary arteries locatedtemporal to optic nerve. 相似文献
102.
Miyaguni T Deguchi S Teruya J Kuniyoshi S Tomita S Soda N Muto Y 《Breast cancer (Tokyo, Japan)》1998,5(2):205-208
A huge phyllodes tumor of the breast that appeared grossly malignant in a 43-year-old woman is described. The patient suffered
from a large breast tumor that suddenly increased in size over 5 months to occupy the entire breast. The tumor was hard, ulcerated
and 20 cm in greatest diameter. Diagnostic imaging (US, CT and MRI) demonstrated a circumscribed mass with a large cystic
cavity. She underwent total mastectomy under a diagnosis of malignant breast tumor. Grossly, the cut surface of the tumor
showed a large cystic cavity surrounding a fleshy, hemorrhagic and necrotic mass with a lobulared or trabeculared appearance.
Unexpectedly, benign phyllodes tumor (PT) without any stromal overgrowth was diagnosed histologically. She has been doing
well since total mastectomy. In our case and in many other reported cases, PT does not show any distinctive correlation between
pathologic findings and tumor behavior. Thus wide local excision is the preferred initial treatment for PT. 相似文献
103.
Interstitial chemotherapy for brain tumors: review 总被引:3,自引:0,他引:3
T. Tomita 《Journal of neuro-oncology》1991,10(1):57-74
An extensive effort to search for curative chemotherapeutic approaches has found no breakthrough in management of patients with malignant brain tumors. Despite the trials with new agents or protocols of multiple agents, systemic chemotherapy has failed to provide reliable clinical response. Interstitial chemotherapy has been practiced for malignant brain tumors with administering chemotherapeutic compounds directly into the tumor which provide increased and prolonged drug concentration in the tumor, reduction of systemic toxicity and bypassing the blood-brain barrier. These theoretical advantages encourage further pursuing interstitial chemotherapy for patients with malignant brain tumors who would otherwise be always fatal.In this review, the literature has been reviewed to identify methods toxicity and efficacy of interstitial chemotherapy. Clinical and experimental data indicate limited toxicity and promising efficacy. Various methods to administer the agents were utilized; intraoperative topical application, local injections through catheters or implantable controlled drug delivery system. Selection of ideal chemotherapeutic agents and development of drug delivery system need further investigations. 相似文献
104.
Effects of the tumor inhibitor IKP-104, a 4(1H)-pyridinone derivative, on cytoskeletal microtubules of cultured tumor cells. 总被引:1,自引:0,他引:1
The effects of IKP-104, a 4(1H)-pyridinone derivative, on the mitotic profile and cytoskeletal microtubule dynamics of cultured B16 melanoma cells were examined in order to investigate the mechanism of its antitumor activity. The exposure to IKP-104 caused accumulation of cells in abnormal metaphase with chromosomes scattered within the cytoplasm and induced polyploid and multinucleate cells as detected by differential staining microscopy with brilliant blue R and safranin O. An immunofluorescence study with monoclonal anti-alpha-tubulin antibody revealed that IKP-104 diminished cytoskeletal microtubules of both interphase and mitotic cells, resulting in induction of a few fragments resembling "microtubular bundles" induced by vinblastine (VLB). These results indicated that IKP-104 arrests cells in the mitotic phase by inhibition of polymerization and induction of depolymerization of cytoskeletal microtubules, similarly to VLB. 相似文献
105.
T Motohiro M Aramaki K Oda A Kawakami T Koga S Tomita Y Sakata F Yamashita K Tanaka Y Matsukuma 《The Japanese journal of antibiotics》1992,45(12):1684-1699
Cefprozil (CFPZ), a newly developed cephalosporin in fine granular form, was administered to pediatric patients with skin and soft tissue infections. MICs were determined for 6 drugs including CFPZ, cephalexin (CEX), cefaclor (CCL), ampicillin (ABPC), methicillin (DMPPC), cloxacillin (MCIPC) against 53 clinical isolates of Staphylococcus aureus from these patients. An inoculum size of 10(6) CFU/ml was used in the MIC-determinations. CFPZ was given to 73 patients with ages ranging from 6 months to 10 years and 8 months and 71 cases were evaluable for clinical effects as follows; impetigo (65), Staphylococcal scalded skin syndrome (1), furuncle (1), subcutaneous abscess (3), and periproctal abscess (1). To study clinical efficacy, bacteriological effects and safety of this drug, a mean dose of 8.4 mg/kg with 3-4 daily dosages (57 cases of t.i.d. and 14 cases of q.i.d.) was administered for an average of 6 days. The results obtained are summarized as follows. 1. With regard to the 53 isolates of S. aureus, MICs of CFPZ against 52 strains (98.1%) ranged from 0.78 to 3.13 micrograms/ml. 45 strains (84.9%) were inhibited at 0.78 micrograms/ml. MIC90 of CFPZ was 1.56 micrograms/ml, but MIC against 1 strain of Methicillin-resistant S. aureus (MRSA) was 100 micrograms/ml. The MIC90 of CEX and CCL were 6.25 micrograms/ml and MIC of CEX and CCL against 1 MRSA strain were 200 and 100 micrograms/ml, respectively. The MIC90 of ABPC, DMPPC and MCIPC were 6.25, 3.13 and 0.39 micrograms/ml, respectively. CFPZ showed the second highest activity after MCIPC against S. aureus. 2. CFPZ showed very good clinical responses and clinical effects in 71 patients all of whom judged by doctors in charge as having "good" or better responses. 3. For impetigo patients, the evaluable cases by score 3, 5 and 7 days after administration of the drug were 52, 39 and 20 patients, respectively. The efficacy rates on these days were 90.4, 100 and 100%, respectively. The efficacy rate at a daily dose of 30.1-45.0 mg/kg on day 3 was 17.2% higher than that at 22.5-30.0 mg/kg, and the "excellent" response rate of 30.1-45.0 mg/kg group was 45.3% greater. Because of these results, it is expected that good clinical effects can be obtained at a daily dose of 22.5-30.0 mg/kg of CFPZ, but better responses can be expected at 30.1-45.0 mg/kg in 3-4 divided doses given for 5 days. 4. Bacteriological effects of CFPZ were determined against 60 strains of S. aureus.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
106.
K Tsuyuki Y Arisawa I Yokoyama K Matsumoto T Ogiwara H Fukagawa C Tomita K Wakamatsu K Nouga 《The Japanese journal of antibiotics》1992,45(2):188-196
Studies were done on the effectiveness and safety of panipenem/betamipron, a new carbapenem antibiotic, in infections in the surgical domain and its safety when dissolved in infusions containing lactate. The obtained results are summarized as follows. The preparation, 0.5 g/0.5 g or 1.0 g/1.0 g, was administered by intravenous drip infusion 2 to 3 times a day to 31 cases of patients with infections in the surgical domain. A physiological saline solution was used as the solvent in 21 cases (group A) of them and Solita T3, an infusion containing lactate, was used as the solvent in the 10 remaining cases (group B). As for its clinical effects, results were rated as "excellent" in 20, "good" in 7, "fair" in 3 and "no response" in 1 out of the 31 cases, and the efficacy rate was 87.1%. Regarding its bacteriological effects, results were rated as "disappeared" in 22, "decreased" in 2, "unchanged" in 1 and "unknown" in 1 out of 26 cases from which bacteria were isolated, hence the bacteria-clearance rate was 88.0%. As for side effects, skin rash was seen in 1 case and slight increases of GOT and GPT were noted as abnormal changes in laboratory data in 2 cases. These side effects were all observed among the cases in group A but not at all in group B where a lactate containing infusion was used as the solvent. 相似文献
107.
Yoshida K Fujii Y Ina H Fujioka S Maseki T Abe T Tokuno H Tomita T 《Journal of anesthesia》1991,5(1):56-59
The effects of sodium and temperature on tension of isolated canine coronary arterial strips were studied.In 20mEq·l
–1 K solution, the strength of tension was inversely related to the Na concentration. At 37°C, the tension was significantly increased at 70mEq·l
–1 Na and below. The tension was gradually suppressed by lowering of the temperature from 37°C to 10°C. At 10°C, tension did not developed significantly at Na concentrations between 127mEq·l
–1 and 12mEq·l
–1.It was concluded that the decrease in Na concentrations increased the tension of the canine coronary artery and the lowering of temperature supressed the tension inducted by the decrease in Na concentrations.(Yoshida K, Fujii Y, Ina H, et al.: Effects of sodium and temperature on tension in isolated canine coronary artery. J Anesth 5: 56–59, 1991) 相似文献
108.
Endogenous adenosine 3',5' -monophosphate (cAMP) levels in mastocytoma P-815 cells, synchronized either at the G1/S transition by amethopterin- or double thymidine-block or in mitosis by colcemid block, were highest during late S and early G2 phases and lowest during mitosis. These cell cycle-dependent changes in cAMP levels were largely accounted for by changes in adenylate cyclase and phosphodiesterase activities. Similar fluctuations occurred simultaneously with specific prostaglandin E1 (PGE1) binding, histidine decarboxylase activity, histamine content, and [35S]SO-2(4) incorporation into glycosaminoglycans of the cells. In addition, endogenous levels of the E group of prostaglandins (PGEs) and "14C]carachiodonic acid incorporations into PGE, phosphatidylcholine and phosphatidylinositol also exhibited fluctuation patterns similar to that of cAMP levels. Since cAMP levels still fluctuated in a serum-depleted medium where DNA synthesis and cell division were inhibited, endogeneous levels of prostaglandin and cAMP appeared not to be regulated solely by serum factor(s). Exposure of cells at G1/S transition to 1-methyl-3-isobutylxanthine (MIX) resulted in 10-fold elevation of cAMP levels throughout the cell cycle without affecting DNA synthesis. On the other hand, PGE1 and/or MIX added at late S phase elevated cAMP levels, prolonged C2 phase and retarded the cell division, but these agents added at the beginning of mitosis elevated cAMP levels without affecting the cell division. These results suggest that prostaglandin newly synthesized by the increased metabolism of phospholipids promote the cAMP synthesis via their binding to the receptors and thereby control the division and phenotypic expression of mastocytoma P-815 cells. 相似文献
109.
Hasegawa M Kawashima S Shikano M Hasegawa H Tomita M Murakami K Kushimoto H Katsumata H Toba T Yoshikawa H Yoshimura E Koide S Murase M Fujii M 《Nihon Jinzo Gakkai shi》2000,42(2):53-59
Cholesterol arterial embolization is a systemic disease resulting from cholesterol crystal embolization to multiple organs, including the kidney, skin, brain, eye, gastrointestinal tract and extremities. In general, it is associated with high morbidity and mortality, but no optimal treatment has yet been developed. In this paper, we report five patients with cholesterol atheroembolic renal failure. In three of the five patients, combined therapy with corticosteroids and plasma exchange was performed. The three patients survived. On the other hand, the two remaining patients died of multifactorial causes. In this report, the literature on steroid therapy for cholesterol atheroembolic renal disease is reviewed and the efficacy of combined therapy by use of corticosteroids and plasma exchange is evaluated. 相似文献
110.
A 65-year-old woman suddenly developed severe headache with nausea. Computed tomographic scans revealed a diffuse subarachnoid hemorrhage with thick hematoma of the left ambient cistern. Cerebral angiogram did not show any aneurysm. On the 7th day after admission, 3D-CT angiogram showed an aneurysm of the left posterior cerebral artery. On the 14th day, axial and coronal magnetic resonance images showed the aneurysm, surrounding structures and the choroidal fissure. On the 26th day after admission, successful neck clipping was performed through the temporal horn via the inferior temporal gyrus. The postoperative course was uneventful except for transient aphasia. This approach may be preferable in such cases, because it protects the brain from the detrimental effects of strong temporal retraction and provides a wider working space. In our case, thin slice MRI and MRA showing the aneurysm in the ambient cistern and the choroidal fissure were useful for deciding the appropriate approach. 相似文献