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71.
We studied choline acetyltransferase (CAT) activity in a rat model of brachial plexus injury. In experiment 1, we found that the CAT activity was remarkably high in the anterior roots and low in the posterior roots. In experiment 2, nerve root segments were extracted and examined for CAT activity in the root avulsion group (group A) and the plexus severance group (group B). CAT activity decreased day by day in group A, reaching about 1/20 of the normal 5 days postoperatively. By contrast, in group B activity decreased only slightly, and even at 90 days postoperatively was about 6,000 cpm (one-half normal level). As a result, CAT activity enabled us to distinghish postganglionic from preganglionic injury of the cervical roots. Furthermore, it was a useful adjunct for minimizing nerve loss in intercostal nerve transfer, distinguishing motor and sensory branches of the intercostal nerve, and evaluating the motor nerve activity. © 1995 Wiley-Liss, Inc.  相似文献   
72.
Developmental toxicity potential of grayanotoxin I (GTX I), a toxic diterpenoid contained in plants of the family Ericaceae, with sodium ionophore activity, was studied in mice and chicks. In mice, intraperitoneal injections of 1.5 mg GTX I/kg body weight of mouse for three consecutive days during the organogenetic period caused some dams to die, but neither embryotoxicity nor teratogenicity was detected. In chicks, a single injection of 0.1-1.0 microgram GTX I per egg into the extraembryonic coelom on day 1.5 or 2 of incubation, or into the amnionic cavity on day 3 or 4 of incubation induced neither embryotoxic nor teratogenic signs, but 10 micrograms GTX I per egg showed lethal effects when applied on each of those days.  相似文献   
73.
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   
74.
We report herein the case of a 77-year-old man with a left ventricular tumor originating from the papillary muscle of the left ventricular wall, in whom a successful tumor resection with mitral valve replacement was performed. The pathological diagnosis of the tumor was confirmed as cardiac fibroma. His postoperative course was uneventful and he is currently well with no signs of recurrence 2 years after surgery.  相似文献   
75.
Background :
The aim of this study was to investigate the influence of osteoarthritis of lumbar vertebrae on serum bone formation and resorption marker levels of patients with benign prostatic hypertrophy (BPH).
Methods :
Serum levels of carboxyterminal propeptide of type I procollagen (PICP), alkaline phosphatase (ALP), carboxyterminaltelopeptide of type I collagen (ICTP), and prostate-specific antigen (PSA) were examined in 40 patients with BPH, and the presence of osteoarthritis at the lumbar vertebrae of the patients was evaluated by plain x-ray-p.
Results :
Findings of osteoarthritis were observed in 23 of the 40 patients (58%), and 10 of the patients had severe osteoarthritis (involving at least 2 lumbar vertebral bodies). The serum levels of PICP, ALP, ICTP, and PSA of the patients without osteoarthritis findings were not different from those of the patients with osteoarthritis or severe osteoarthritis.
Conclusion :
The influence of osteoarthritis on serum bone formation and resorption marker levels of patients with BPH appears to be rather slight, if there is any influence at all.  相似文献   
76.
The aim of this study was to assess the significance of C3 deposition in IgA nephropathy in children and adolescents. One hundred and two patients aged 5–21 years (57 male and 45 female) were studied. The findings of C3 deposition were classified into 8 groups by immunofluorescent (IF) pattern and intensity as follows: group MC3+ (N = 12): mesangiocapillary pattern and 3+ in intensity; group MC2+ (N = 13): mesangiocapillary and 2+; group MC1 + (N = 4): mesangiocapillary and 1 +; group M3+ (N = 11): mesangial and 3+; group M2+ (N = 24): mesangial and 2+; group M1 + (N=18): mesangial 1 +; group S (N = 12): only segmentally positive; and group N (N = 8): negative. Histological changes were scored semiquantitatively as an activity index (cellular proliferation, necrosis, interstitial cell infiltration, and cellular crescents) and a chronicity index (mesangial sclerosis, segmental and global glomerular sclerosis, fibrous crescents, adhesion and tubulo-interstitial change). IF findings were scored semiquantitatively and laboratory findings were also studied. The following results were obtained: 1) The scores of total activity index in MC groups were higher than in the M, S or N groups, and the greater the degree of C3 deposition, the higher the score; 2) Such result was not evident in the chronicity index; 3) High IF scores of IgG and IgM were found in the MC3+ and MC2+ groups; 4) Hematuria was more severe in MC3+ and MC2+ than in other groups, and proteinuria was more prominent in the MC than other groups. Thus the degree of C3 deposition was parallel with histological activity and urinary findings.  相似文献   
77.
A case is reported of Wilms' tumor associated with multiple pulmonary metastases histologically showing maturation of the tumor cells at 9 years after the resection of the primary tumor and intensive therapy. A huge tumor of a 22-month-old patient's right kidney was resected. The tumor was diagnosed as Wilms' tumor of mesenchymal type (stage 1), which consisted of predominantly immature mesenchymal tissue including rhabdomyoblasts, smooth muscle and fibrous tissue, and few blastemal and epithelial components. Intensive preoperative and postoperative chemotherapy with actinomycin D and vincristine and postoperative irradiation therapy totaling 16 Gy were carried out. The patient was regularly followed up uneventfully until 9 years after the surgery. On routine chest x ray at the age of 10 years 11 months, multiple pulmonary nodules were found. The excised nodules from the bilateral lungs disclosed similar histology, exclusively composed of dense collagen bundles and fibrocytes intermingled with mature striated muscle bundles. No immature tumor components were detected. The possible effect of intensive therapy in this maturation was stressed, although spontaneous benign differentiation of tumor cells cannot be excluded.  相似文献   
78.
1. By use of front-surface fluorometry with fura-2-loaded rabbit femoral arterial strips, both the cytosolic Ca2+ concentration ([Ca2+]i) and force were simultaneously monitored. By utilizing the [Ca2+]i-force curves, we were thus able to examine the temporal changes in the relationships between [Ca2+]i and force ([Ca2+]i-force relationship) during contractions induced by a high external K+ solution, noradrenaline (NA) and 5-hydroxytryptamine (5-HT). 2. The 'basic' [Ca2+]i-force relationship of the Ca(2+)-induced contractions was obtained by the cumulative applications of extracellular Ca2+ (0-10 mM) during 118 mM K(+)-depolarization (Ca(2+)-contractions). 3. When each vascular strip was exposed to high external K+ (30 mM K(+)-118 mM K+) solutions, the [Ca2+]i abruptly increased until it reached a peak, and then slightly decreased and eventually reached a steady-state level. The force also rapidly rose to reach a maximum plateau level. The changes in [Ca2+]i were more rapid than those in the force. Thus, the [Ca2+]i-force curves observed during the contractions induced by high+ (30 mM-118 mM) solutions showed a counter-clockwise rotation, over time. The entire curve shifted to the right, in a concentration-dependent manner, as compared with the line of the 'basic' [Ca2+]i-force relationship of the Ca(2+)-contraction. However, the [Ca2+]i-force relationship of the steady-state of contractions induced by the single dose applications of high K+ (30 mM-118 mM) overlapped with the line of the 'basic' [Ca2+]i-force relationship of Ca(2+)-contractions. 4. As references, the levels of [Ca2+]i and the force at rest (without stimulation) and at the steady-state of the contractions induced by a single dose application of 118 mM K+ solution were designated as 0% and 100%, respectively. When the vascular strips were exposed to NA (10(-5) M) and to 5-HT (10(-4) M), the [Ca2+]i abruptly rose, and reached a peak (107.1 +/- 5.8%) and 101.3 +/- 2.8%, respectively) after 1 min and 2 min, respectively (the [Ca2+]i-rising phase), and thereafter declined with a similar time course (the [Ca2+]i-declining phase) until reaching a low steady level (the steady-state phase). The force induced by 10(-5) M NA and 10(-4) M 5-HT reached a peak at 4 min (129%) and at 2 min (115%), respectively, and thereafter gradually declined. In contrast to the similarity in the [Ca2+]i transient between NA and 5-HT, the force induced by NA declined more slowly and reached higher steady levels than that seen with 5-HT.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
79.
80.
During the span of five years from October, 1987 to December, 1992, we have operated on six cases of carotid body tumours. Total excision was performed in five patients; one patient had 90% of the tumour excised. All patients had pre-operative balloon occlusion test; only one patient showed electroencephalographic changes. Three patients required intra-operative intraluminal shunts for various reasons. Microvascular Doppler flowmetery confirmed patency and correct placement of the shunt. Elective use of the intraluminal shunt is very useful for safe excision of carotid body tumours. Microneurosurgical techniques were used for all patients. There were no cerebrovascular sequelae and 25% of patients experienced cranial nerve injury. Average follow up was three years and none of the total excision patients have had recurrence of the tumours.  相似文献   
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