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41.
BACKGROUND: Ketotic hypoglycemia is the most common cause of recurrent hypoglycemia in early childhood but its etiology is poorly understood. Elimination diets have been used for the prevention or treatment of some allergic diseases; however, these diets entail a risk to the normal nutrition and growth of children. The present study investigated whether elimination diets are related to the occurrence of ketotic hypoglycemia. METHODS: The prevalence of allergy treated with elimination diet therapy was retrospectively investigated in 18 patients with ketotic hypoglycemia seen in Yamaguchi University Hospital between January 1995 and September 1999. Data were gathered by reviewing the patients' medical charts. RESULTS: Ten (55.6%) of 18 patients with ketotic hypoglycemia had allergic diseases. Six (60%) of the patients had been treated with strict elimination diets and the others were on incomplete elimination diets for the prevention of allergy. The ketotic hypoglycemia patients with allergic diseases had experienced fewer pre-existing infectious diseases than those without allergic diseases. CONCLUSIONS: Patients with allergic diseases treated with elimination diets have a relatively high tendency towards developing ketotic hypoglycemia. They might have a lower capacity to tolerate fasting due to their excessive avoidance of many foods, even during periods when they are not undergoing strict elimination diets.  相似文献   
42.
Abstract Background: Yolk sac tumors (YST) exhibit several different histological subtypes and the mechanisms of cellular differentiation and prognosis of each subtype remain unknown.
Results: We report two infants with sacrococcygeal YST; one represented a typical histological subtype and the other showed a hepatoid subtype with uniform histology. The isoform of alpha-fetoprotein (AFP) in the patient with the hepatoid pattern was examined by lectin-affinity Immunoelectrophoresis and represented as a YST. but not hepatocellular, subtype. The patient with typical YST responded well to VAB-6 combination chemotherapy. However, this regimen was only partially effective to the patient with the pure hepatoid histological subtype, and an etoposide with ifosfamide and cisplatin (VIP) regimen as a salvage chemotherapy combined with complete tumor resection was useful to achieve complete remission (CR). Both of the patients have been in CR for more than four years.  相似文献   
43.
Recently, we demonstrated that some A-ring-modified vitamin D3 analogs had unique biological activity. Of these analogs, 2alpha-propoxy-1alpha,25(OH)2D3 (C3O1) and 2alpha-(3-hydroxypropoxy)-1alpha,25(OH)2D3 (O2C3) were examined for metabolism by CYP27A1 and CYP24A1. Surprisingly, CYP27A1 catalyzed the conversion from C3O1 to O2C3, which has 3 times more affinity for vitamin D receptor than C3O1. Thus, the conversion from C3O1 to O2C3 by CYP27A1 is considered to be a metabolic activation process. Five metabolites were detected in the metabolism of C3O1 and O2C3 by human CYP24A1 including both C-23 and C-24 oxidation pathways. On the other hand, three metabolites of the C-24 oxidation pathway were detected in their metabolism by rat CYP24A1, indicating a species-based difference in the CYP24A1-dependent metabolism of C3O1 and O2C3 between humans and rats. Kinetic analysis revealed that the Km and kcat values of human CYP24A1 for O2C3 are, respectively, approximately 16 times more and 3 times less than those for 1alpha,25(OH)2D3. Thus, the catalytic efficiency, kcat/Km, of human CYP24A1 for O2C3 is only 2% of 1alpha,25(OH)2D3. These results and a high calcium effect of C3O1 and O2C3 in animal experiments using rats suggest that C3O1 and O2C3 are promising for clinical treatment of osteoporosis.  相似文献   
44.
We report a case of a compound adrenal medullary tumor. A 63-year-old woman was referred to our hospital for examination of a right adrenal tumor, incidentally found by abdominal computed tomography (CT). CT and magnetic resonance imaging (MRI) revealed a round heterogeneous tumor, 5 cm in diameter, on the upper pole of the right kidney. A view of the total body scan demonstrated the uptake into the tumor after the injection of 123I-metaiodobenzyl-guanidine. Serum and urinary adrenaline levels were slightly elevated, and urinary excretion of vanillylmandelic acid was markedly elevated. Her blood pressure was normal. From these findings, the tumor was suspected to be a pheochromocytoma of the right adrenal gland and was resected reteroperitoneally. Pathological diagnosis was a compound adrenal medullary tumor, which was composed of pheochromocytoma and ganglioneuroma. This combination of the adrenal medullary tumor is extremely rare, and to date this case may be the sixth case in the Japanese medical literature.  相似文献   
45.
OBJECTIVE: Under the fee-for-service system, the overuse and misuse of perioperative antibiotics have become serious concerns in Japan. The objective of the present study is to investigate practice variations of perioperative antimicrobial prophylaxis between and within hospitals, and to identify any opportunities for improvement. METHODS: We polled 319 surgeons in six specialties employed by 11 teaching hospitals in Japan. We developed questionnaires with vignettes, asking physicians about their practice of antimicrobial prophylaxis in six surgical procedures (gastrectomy, hysterectomy, cataract surgery, clipping of cerebral aneurysm, hip fracture surgery, and coronary artery bypass graft) and utilization of institutional clinical pathways. RESULTS: Average durations of prophylaxis varied by procedure, from 1.6 days for cataract surgery to 5.8 days for clipping surgery. Variation was also observed between institutions for the same procedure, e.g. institutional averages for the duration of prophylaxis for gastrectomy ranged from 2.3 to 7 days. Large intra-institutional variation in prophylaxis duration and inconsistent use of clinical pathways were observed in the cases of gastrectomy, hip fracture surgery, and clipping surgery. At one hospital, 20% of physicians performing gastrectomy indicated the use of an institutional clinical pathway, and prophylaxis duration ranged from 3 to 6 days. For cataract surgery and hysterectomy, clinical pathways were universally applied and intra-institutional practice variation was small, yet prophylaxis duration varied widely between hospitals and third-generation cephalosporins were used extensively. Average length of prophylaxis for hysterectomy ranged from 1.8 to 6 days and 43% of respondents prescribed third-generation cephalosporins. CONCLUSIONS: In Japan, perioperative antimicrobial prophylaxis lacks standardization. Efforts to strengthen an evidence-based approach to antimicrobial prophylaxis need to be made a priority at both the national and institutional levels.  相似文献   
46.
BACKGROUND: The authors clarified the clinical significance of the measurement of serum concentrations of specific IgE antibodies to staphylococcal enterotoxin (SE) A- and SEB in atopic dermatitis (AD). METHODS: The serum concentrations of SEA- and SEB-specific IgE antibodies in 140 pediatric patients with AD were measured with an immuno CAP -radioallergosorbent test system (RAST). To check the cross-reaction of specific IgE antibodies to SEA/SEB and other allergens, the CAP RAST fluorescent enzyme immunoassay inhibition test was performed. RESULTS: Forty-seven patients (33.6%) tested positive for either SEA- or SEB-specific IgE antibodies. School children showed higher positive rates of SEA/SEB-specific IgE antibodies than infants or young children. The patients with severe AD and those with exacerbation of symptoms in summer, had higher positive rates of SEA/SEB-specific IgE antibodies than patients with mild AD or those with exacerbation in winter. In addition, the positive rates of specific IgE antibodies to both dog-dander and cat-dander were higher in patients with positive SEA/SEB-specific IgE antibodies than in patients with negative ones. No cross-reactions occurred among specific IgE antibodies to SEA/SEB and dog/cat dander with one patient's serum, which had positive IgE-specific antibodies against cat/dog dander and SEA/SEB. The positive rate of SEA/SEB-specific IgE antibodies in the patients with dogs and/or cats as pets was 48.4%, which was higher than in those with no pets. CONCLUSIONS: Atopic dermatitis patients who exhibit high positive rates of SEA/SEB-specific IgE antibodies were found to be school children, severe cases, cases with high serum concentrations of total IgE, cases with exacerbation in summer, and cases with dogs and/or cats as pets. The measurement of serum concentrations of specific IgE antibodies to SEA and SEB, thus has some value for evaluating AD patients.  相似文献   
47.
48.
The usefulness of the vascular ultrasound in the field of obstetrics is now well recognized. Intima-media thickness (IMT) and elastic property of the common carotid artery are affected by pregnancy and vary with complications. Flow-mediated vasodilation (FMD) of the brachial artery reflects the vascular endothelial function and is reported to be useful in the management of complicated pregnancy, especially pre-eclampsia. For the screening of deep vein thrombosis of the lower extremities in the perinatal period, compression ultrasonography (CUS) is useful.  相似文献   
49.
Breast cancer resistance protein (BCRP) is a recently identified ATP-binding cassette transporter, important in drug disposition and in the development of multidrug resistance in cancer. Flavonoids, a major class of natural compounds widely present in foods and herbal products, have been shown to be human BCRP inhibitors. The objective of the present study was to evaluate the potential for in vivo pharmacokinetic interactions by comparing the pharmacokinetics of topotecan (a model BCRP substrate) after oral administration of 2 mg/kg topotecan with and without different doses of the flavonoids chrysin or 7,8-benzoflavone (BF) in rats and mdr1a/1b (-/-) mice. Coadministration of 50 mg/kg GF120918 [N-(4-[2-(1,2,3,4-tetrahydro-6,7-dimethoxy-2-isoquinolinyl)ethyl]-phenyl)-9, 10-dihydro-5-methoxy-9-oxo-4-acridine carboxamide] with 2 mg/kg topotecan significantly increased the area under the plasma concentration-time curve and bioavailability of topotecan by more than 4-fold in these animals, indicating the importance of BCRP in the bioavailability and disposition of topotecan in rats. Chrysin (50 microM) and BF (5 microM) significantly inhibited the BCRP-mediated transport of topotecan in BCRP-overexpressing MCF-7 MX100 cells (MCF-7 cells selected with mitoxantrone) to a level comparable to that observed with 10 microM fumitremorgin C (a potent BCRP inhibitor). However, neither chrysin nor BF significantly altered topotecan pharmacokinetics in rats or in mdr1a/1b (-/-) mice after oral coadministration of doses up to 50 mg/kg. The reason(s) for this lack of in vitro-in vivo association may be the lack of potent inhibition activity of the flavonoids against mouse or rat BCRP, as evidenced by our observation that these flavonoids have only weak, if any, inhibition activity against mouse Bcrp1-mediated transport of topotecan in MDCK-Bcrp1 cells.  相似文献   
50.
It is likely that a close association exists between findings obtained by two methods: dobutamine stress echocardiography and 123I-MIBG scintigraphy. Both of these methods are associated with beta-adrenergic receptor mechanisms. This study was conducted to demonstrate the relation between myocardial response to dobutamine stress and sympathetic nerve release of norepinephrine in the failing heart. In 12 patients with heart failure due to idiopathic dilated cardiomyopathy, the myocardial effects of dobutamine stress were evaluated by low-dose dobutamine stress echocardiography: and sympathetic nerve function was evaluated by scintigraphic imaging with iodine-123 [123I] meta-iodobenzylguanidine (MIBG), an analogue of norepinephrine. Echocardiography provided quantitative assessment of wall motion and left ventricular dilation; radiotracer studies with 123I-MIBG provided quantitative assessment of the heart-to-mediastinum (H/M) uptake ratio and washout rate. Results showed that H/M correlated with baseline wall motion (r = 0.682, p = 0.0146), wall motion after dobutamine stress (r = 0.758, p = 0.0043), the change in wall motion (r = 0.667, p = 0.0178), and with left ventricular diastolic diameter (r = 0.837, p = 0.0007). In addition, the 123I-MIBG washout rate correlated with baseline wall motion (r = 0.608, p = 0.0360), wall motion after dobutamine stress (r = 0.703, p = 0.0107), and with the change in wall motion (r = 0.664, p = 0.0185). Wall motion, especially in the myocardial response to dobutamine stress, is related to sympathetic nerve activity in heart failure.  相似文献   
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