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41.
A total number of 427 patients with tetralogy of Fallot who underwent corrective surgery between 1960 and March 1990, in whom 211 patients who survived the surgery over 10 years were evaluated for the follow-up studies. Hemodynamic and cardiac function studies were carried out in 101 patients at the mean interval of 15.7 years (ranges 2 to 21 years). Three methods indicated that patients with muscle resection and pulmonary valvulotomy without patch enlargement (NP) had worse results than the groups with RV patch below valve (RP) and with transannular patch (TP). Also, Holter ECG revealed ventricular arrhythmias in patients with NP were more common than the groups with RP and TP. Sixteen patients (13 with NP, 2 with TP and one with RP) were required reoperation for residual ventricular shunt in 13, residual pulmonary stenosis in 11 and tricuspid regurgitation in 2. All of these 16 patients survived operation and obtained excellent clinical status. It is concluded that patients with TOF after corrective surgery should be carefully followed with short term interval to prevent sudden death and postoperative complications.  相似文献   
42.
HTX rat, a congenital hydrocephalic strain, develops ventricular dilatation and cystic cavities in the cerebral white matter after birth. To investigate the reactive changes in glial cells around these cavities, immunohistochemical staining for glial fibrillary acidic protein (GFAP), a specific marker protein of astrocytes, and bromodeoxyuridine (BrdU), a thymidine analogue, was carried out on 107 Wistar and HTX rat brains from birth to postnatal day (P) 26. Animals were divided into three groups: Group A, Wistar rats as normal controls; Group B, HTX rats with a normal structure or only mild ventricular dilatation without any lesion in the white matter; and Group C, HTX rats with severe ventricular dilatation and cyst formation in the white matter. Group B rats showed similar development of GFAP-positive (GFAP+) cells to that in Group A rats, both morphologically and quantitatively. On the other hand, Group C rats showed definite structural changes in GFAP+ cells around the cystic cavities from P5. These included enriched cytoplasm and thickened cell processes with increased GFAP expression, and enveloped most cyst walls from P10. However, quantitative examination of the percentage of GFAP+ cells in Group C rats showed a similar developmental profile to those in Group A and B rats. Furthermore, the labeling index of BrdU-positive cells, indicating S-phase cells, in the white matter in Group C rats showed a similar decreasing pattern to that in Group A and B rats from P1 to P26.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
43.
A 50-year-old woman with anorexia nervosa was admitted for evaluation of neutropenia (WBC 1,600/microliters). Her bone marrow was gelatinous, and myeloid cells had decreased. Homogeneous substance deposited in the marrow, stained by alcian blue (pH 2.5), indicative of acid mucopolysaccharides. CFU-G and CFU-GM were decreased in number and myeloid pool in the bone marrow also decreased. Anti-neutrophilic antibody was negative. Neutropenia may be related to myeloid hypoplasia, due to increase of acid mucopolysaccharides replacing adipose cells in the bone marrow under long-term mal-nutritional state. Neutrophils markedly increased by administration of rhG-CSF 5.0 micrograms/kg/day for 14 days without the first peak. Serum G-CSF level did not increase (less than 60 pg/ml). It is effective to administer G-CSF to anorexia nervosa with neutropenia.  相似文献   
44.
There is no definitive surgical procedure for acquired lesions of the tricuspid valve (TV). From Feb, 1978, through March, 1990, the surgical treatment for the organic lesions of TV was performed in 10 patients, repair in 6 and TV replacement in 4. TV was repaired by commissurotomy, annuloplasty or valvuloplasty, or combination of them. When residual significant tricuspid regurgitation (TR) and/or stenosis (TS) was detected by intraoperative pulsed Doppler echocardiography after reparative procedures, TV was replaced. Follow-up periods ranged from 1 to 12 years (mean, 45.3 months). There was no early death, and late death was noted in one patient 32 months after operation. Preoperatively, 7 patients were in NYHA class IV and 3 in class III. Out of survivors, 7 are in class I and 2 in class II because of progression of mitral stenosis or coronary artery disease. Following surgery, the patients exhibited significant decrease in the cardiothoracic ratio (69.3 +/- 7.2 to 56.9 +/- 6.4%; p less than 0.01) and in the mean right atrial pressure (11.4 +/- 3.6 to 8.6 +/- 3.1 mmHg; p less than 0.05). The postoperative right ventriculography showed mild to moderate TR in 3 of 6 patients who underwent TV repair. In conclusion, TV repair could be a reasonable procedure for the organic TV lesions, although careful follow-up is recommended for residual TR.  相似文献   
45.
We report the case of a patient with delayed methotrexate (MTX)-induced leukoencephalopathy who showed a marked improvement both in clinical and neuroimaging findings after a high-dose of the active form of folinic acid (leucovorin) treatment. The patient developed progressive affective impairment accompanied by headache, nausea and vomiting after treatment with MTX during the chemotherapy for acute lymphoblastic leukemia, and diagnosed as delayed type MTX-induced leukoencephalopathy. After an intravenous injection of high-dose folinic acid (total 1920 mg), neurological deficits and white matter changes dramatically improved in a few weeks. Although delayed MTX-induced leukoencephalopathy may cause irreversible brain damage, an early treatment with high dose leucovorin may thus facilitate the marked improvement of clinical findings and white matter abnormalities.  相似文献   
46.
To elucidate the penetrability of carteolol, a β-adrenoceptor antagonist (β-blocker) into the brain of rats, intracerebral and serum concentrations of the compound were determined in male rats receiving single or repetitive oral administration of carteolol hydrochloride at 30 mg/kg. The time-course of the intracerebral concentration of carteolol following single IV administration of the compound at 10 and 30 mg/kg was also studied in male rats. A high-performance liquid chromatography method was used to determine the intracerebral and serum concentrations. Following single oral dosing, the intracerebral concentration of carteolol reached a maximum of 0.074 μg/g at 2 h postdosing and declined with a half-life of 3.7 h, and the Cmax and AUC of carteolol in the brain were 12.5% and 19.8% of those in serum. The intracerebral and serum concentrations of carteolol were determined in male rats receiving repetitive oral dosing of the compound once daily for 7 days. The concentration of carteolol in the brain and serum at 1 h postdosing varied within a range of 0.059–0.091 μg/g and 0.321–0.443 μg/ml, respectively, throughout the dosing period, showing no changes in the penetrability of the compound into the brain due to repeated dosing. The concentration of carteolol in the brain and serum increased in a dose-dependent manner in rats receiving a single IV administration of the compound. The elimination half-life of carteolol in the serum and brain was 0.6–0.8 h and 1.3–1.7 h, respectively, in rats following single IV dosing of the compound. The half-life in the brain was about twice as long as that in the serum. The brain to serum concentration ratio was 0.306:0.499. From the above results, it was concluded that carteolol is distributed from the circulation to the brain with low penetrability. Received: 30 October 1996/Final version: 16 December 1996  相似文献   
47.
1. To examine whether cytosolic Ca2+ in smooth muscle cells distributes evenly, cytosolic Ca2+ levels were measured with two different Ca2+ indicators in the ferret isolated portal vein; a fluorescent indicator, fura-PE3, that shows the average Ca2+ level, and a photoprotein, aequorin, that preferentially shows a high Ca2+ compartment. 2. A noradrenaline (10 microM)-induced sustained contraction was associated with a sustained increase in the fura-PE3 signal, or a transient increase followed by small sustained increase in the aequorin signal. A high K(+)-induced contraction was associated with a sustained increase in both the fura-PE3 and aequorin signals. 3. A second application of noradrenaline or high K+ induced reproducible contractions and fura-PE3 signals. In contrast, the aequorin signal resulting from a second application of noradrenaline or high K+ was much smaller than the first signal. 4. Following a 13 h but not a 3 h resting period, the aequorin signal stimulated by noradrenaline or high K+ recovered, without any change in the contractile response. 5. In Ca(2+)-free solution, high K+ was ineffective, whereas noradrenaline induced only a small aequorin signal and contraction compared to those obtained in the presence of external Ca2+. After the addition of Ca2+, the first application of noradrenaline induced a large aequorin signal and a large contraction, although a second application induced a much smaller aequorin signal accompanied by a large contraction. 6. These results suggest that high K+ and noradrenaline increase Ca2+ in at least two cytosolic compartments; a compartment that is coupled to the contractile mechanism ('contractile' Ca2+ compartment; major portion of cytoplasm containing contractile elements) and a compartment that is not coupled to contractile mechanisms ('non-contractile' Ca2+ compartment; small sub-membrane area that does not contain contractile elements). On stimulation, the Ca2+ level in the 'contractile' compartment may increase to a level high enough to stimulate myosin light chain kinase but not so high as to consume aequorin rapidly. In contrast, the Ca2+ level in the 'non-contractile' compartment may increase so greatly that aequorin in this compartment is rapidly consumed. These two compartments may be separated by a diffusion barrier and, during a resting period, aequorin may slowly diffuse from the 'contractile' compartment to the 'non-contractile' compartment and thus restore the full aequorin signal. An increase in Ca2+ in the 'non-contractile' compartment seems to be dependent mainly on Ca2+ influx and partly on Ca2+ release.  相似文献   
48.
Epidural spinal cord stimulation was carried out in 4 patients with denervation caused by spinal cord lesion, and we reviewed previously reported cases. Initial result showed at 1 week in 100% of our cases, but about 1/3 of the cases, even those with the same denervation caused by spinal cord lesion, had no pain relief at this stage in previously reported cases. In our cases, excellent pain relief was gained temporarily, even though the painful area and the spinal cord lesion were separated somatotopically in 2 cases (case 3, 4). Temporary success bore no relationship to quality and duration of pain. In all cases except case 1, a rapidly decreasing effectiveness was noted, and finally no pain relief was gained at all after 4, 3 and 5 months, respectively. In case 1 there was persistent pain relief estimated at 70-80% after 19 months, only when the spinal cord was stimulated. Epidural stimulation also produced sensations in the painful area. Spinal cord stimulation would suppress at least the dorsal horn neurons which were destroyed by various kinds of diseases. A decline in effectiveness with time would occur due to essential causes of the deafferentation pain, such as anatomical and regeneration factors.  相似文献   
49.
OBJECTIVE: Continuous retrograde cerebral perfusion during aortic arch surgery is associated with cerebral edema. In this report, we describe the clinical use of a new type of intermittent retrograde cerebral perfusion. SUBJECTS AND METHODS: Fourteen patients with a Stanford type A dissection were included in this study. With the usual method of retrograde cerebral perfusion, about 2,500 mL venous blood is drained from bicaval cannulae into a hard-shell reservoir, and oxygenated blood is perfused through the superior vena caval cannula. The flow rate is 300 mL/min. After about 15 min, retrograde perfusion is discontinued, and drainage from the bicaval cannulae is restarted. When a bloodless field is necessary, perfusion also is discontinued. RESULTS: Two to seven cycles of intermittent retrograde cerebral perfusion were administered (average, 3.1+/-0.4, mean+/-SD). The total retrograde perfusion time was 36.0+/-1.9 min which was equivalent to 74.8% of the circulatory arrest time. No patient developed edema of the upper body. The time to wake-up was 3 to 14 h (average, 6.5+/-1.0 h). No patient suffered any neurologic complications even though the time of circulatory arrest was greater than 60 min in four cases. Head magnetic resonance imaging or computed tomography was performed in 12 cases, and no evidence of hypoxic brain injury was detected. CONCLUSIONS: Our clinical experience using a moderate amount of intermittent retrograde cerebral perfusion is superior to continuous retrograde cerebral perfusion for protecting the brain during aortic arch surgery.  相似文献   
50.
M Abe  K Tasaki  K Tominaga  S Fukuhara  S Imai  T Osato  H Wakasa 《Cancer》1992,69(3):763-771
Two human Burkitt's lymphoma cell lines (HBL-4 and HBL-5) were established individually from two patients with small noncleaved cell lymphoma (Burkitt's type). The HBL-4 cell line is Epstein-Barr virus (EBV)-negative, and the HBL-5 cell line is EBV-positive. Cytogenetically, both cell lines had the same chromosomal translocation, t(8;14)(q24;q32) as those observed in the primary malignant cells from individual patients. Morphologic, immunophenotypic, cytogenetic, and molecular studies confirmed that both cell lines were derived from the primary lymphoma cells in vivo. HBL-4 cells lacked CD23(H107), CD11a(LFA-1), and latent membrane protein (LMP) but expressed CD54(ICAM-1) at low levels, whereas HBL-5 cells showed the high level of expression of CD54 and faint expression of LMP but lacked CD11a. In addition, the EBV-positive lymphoblastoid cell line (LCL) expressed CD11a, CD23, CD54, and LMP at high levels. Therefore, an HBL-5 phenotype with expression of CD54 and LMP tends toward an LCL phenotype, and the augmentation of CD54 on the HBL-5 cells in comparison with primary lymphoma cells is likely to be upregulated by LMP, probably resulting from the EBV infection. There was little difference in the BrdUrd uptake in vivo and in vitro, doubling time, tumorigenicity, and dynamics of tumor growth in athymic nude mice between both cell lines. These findings indicate that the potentiality of cell growth and tumorigenicity of these two cell lines are unlikely to be related with EBV.  相似文献   
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