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71.
A 7-year-old girl had growth retardation, hypertension, and hypokalemic alkalosis. Baseline serum aldosterone concentration and plasma renin activity were low and unresponsive to sodium deprivation and to orthostatic changes. Baseline serum progesterone, 17-hydroxyprogesterone, 11-deoxycortisol, and cortisol levels were normal and adequately responsive to ACTH stimulation. No steroid was found abnormally elevated. A diagnosis of 11 beta-hydroxysteroid dehydrogenase deficiency was established on the basis of elevated urinary tetrahydrocortisol plus allotetrahydrocortisol/tetrahydrocortisone ratio, determined by gas chromatography-mass spectrometry. Evaluation of bone mineral metabolism and parathyroid function, and skeletal radiographs, revealed the presence of rickets and secondary hyperparathyroidism. Treatment with spironolactone alone for 2 months corrected hypertension, hypokalemic alkalosis, and all laboratory and radiologic evidence of rickets and hyperparathyroidism, resulting in acceleration of growth rate. The response to spironolactone suggests that a hypermineralocorticoid state is responsible for the hypertensive syndrome and that rickets and hyperparathyroidism could be a consequence of excess mineralocorticoid activity.  相似文献   
72.
This article presents a 3-year prospective study that includes 103 consecutive patients (137 hips) diagnosed with developmental dysplasia of the hip (DDH) at birth. Treatment was started after 2 weeks only if the hips had not stabilized spontaneously. Sonographic studies were first used when clinical stability was confirmed to ensure a true concentric hip reduction. The authors conclude that most patients with DDH at birth (73.8%) do not need treatment at that time, presenting with normal hips at the end of follow-up. When instability was still present after 2 weeks and a splint was applied (26.2%), there were no significant hip differences when compared with a control group of 50 patients (69 hips) who underwent treatment in the first days of life. With this approach, the authors could safely reduce the number of patients to be treated, the amount of sonographic studies, and consequently the final cost of the whole treatment.  相似文献   
73.
Severe trauma is the leading cause of death in the working population. Traffic accidents are the most frequent etiological factor, with substantially more male than female victims. In this paper we have analyzed 53 cases of dead patients, among 240 severe traumatized treated in Center of emergency surgery, Emergency Center, CCS from January, 2000-June 2002. Spleen is the most frequent injured abdominal organ. In 34% surviving period was less than 72 hours. One-third of patients required at least two surgeries, including laparotomy. The most preciously diagnosis were performed in the cases of spleen injuries. The most common cause of death was cariopulmonal insufficiency, according both clinical diagnosis and forensic findings.  相似文献   
74.
Quercetin, one of the most widely distributed flavonoids in the plant kingdom, inhibits various enzymes. This study examined its inhibitory effect on the angiotensin-converting enzyme activity through the cardiovascular response to bradykinin and angiotensin I. Quercetin pre-treatment (88.7 micromol/kg p.o., 45 min; 14.7 micromol/kg i.v., 5 min) significantly potentiated the hypotensive effect of bradykinin (10 nmol/kg i.v.). This association was significantly attenuated by an antagonist of the B2 receptor. In addition, the hypertensive response to angiotensin I (0.1 nmol/kg i.v.) was significantly reduced by quercetin pretreatment using the same parameters as before. These results suggest an inhibitory effect of quercetin on the angiotensin-converting enzyme activity, similar to that of captopril. Quercetin was equally effective when given orally or intravenously.  相似文献   
75.
STUDY OBJECTIVE: To compare continuous versus intermittent administration of piperacillin-tazobactam with regard to clinical, microbiologic, and economic outcomes. DESIGN: Prospective, open-label controlled study SETTING: Community teaching hospital. PATIENTS: Ninety-eight hospitalized patients prescribed piperacillin-tazobactam. INTERVENTION: Substitutions were implemented so that 47 patients initially prescribed intermittent infusion of piperacillin-tazobactam were switched to continuous infusion of this drug combination. Dosages varied in accordance with the type of infection and each patient's renal function. Fifty-one other patients with similar demographics and types of infection received intermittent infusion with piperacillin-tazobactam. MEASUREMENTS AND MAIN RESULTS: Clinical success rates were 94% for the continuous-infusion group and 82% for the intermittent-infusion group (p=0.081). Microbiologic success rates were 89% for the continuous-infusion group and 73% for the intermittent-infusion group (p=0.092). Days to normalization of fever were significantly lower (p=0.012) in the continuous-infusion group (1.2 +/- 0.8 days) than in the intermittent-infusion group (2.4 +/- 1.5 days). Level 1 and level 2 costs/patient were both reduced by continuous infusion, although the difference was statistically significant only for level 2 costs ($399.38 +/- 407.22 for continuous infusion vs $523.49 +/- 526.85 for intermittent infusion, p=0.028). CONCLUSION: Continuous infusion of piperacillin-tazobactam provided clinical and microbiologic outcomes equivalent to those for intermittent infusion. Compared with intermittent infusion, continuous infusion significantly shortened the time to temperature normalization, while also offering a significant reduction in level 2 expenditures.  相似文献   
76.
77.
Restoration of single-stage implants with solid abutments traditionally requires the use of an impression index cap, an analog and a lab fee commensurate with a more complex restoration. A technique is discussed that utilizes standard crown and bridge techniques that simplifies the lab procedure and reduces the prosthetic costs involved with fabrication of implant borne crowns.  相似文献   
78.
The objective of this study was to further elucidate the relationship between relevant biological, behavioural, socio-economic and psychological conditions, experienced in very early life and along the life course, and dental caries experience using the life course approach. A two-phase study was carried out in Brazil. In the first phase, 652 13-year-olds were clinically examined and interviewed. In the second phase, 330 families were randomly selected for interview to collect information on the teenagers' early years of life. Clinical assessment included dental caries, periodontal and traumatic dental injury status. The data analysis involved multiple logistic regression analysis. Adolescents born in a non-brick house, those with a low birth weight and those who were the second or later child in the family were statistically significantly more likely to have a high DMF-T. In conclusion, the results of this study show that there is an association between socio-economic and biological factors in very early life and levels of caries in adolescents.  相似文献   
79.
Type 1 diabetes is a chronic progressive autoimmune disease characterized by mononuclear cell infiltration, dominated by interleukin-12 (IL-12)-dependent Th1 cells, of the pancreatic islets, with subsequent destruction of insulin-producing beta-cells. Here, we demonstrate that treatment of adult nonobese diabetic (NOD) mice with an analog of 1alpha,25-dihydroxyvitamin D(3), an immunomodulatory agent preventing dendritic cell maturation, decreases lipopolysaccharide-induced IL-12 and gamma-interferon production, arrests Th1 cell infiltration and progression of insulitis, and inhibits diabetes development at nonhypercalcemic doses. Arrest of disease progression is accompanied by an enhanced frequency in the pancreatic lymph nodes of CD4(+)CD25(+) regulatory T-cells that are able to inhibit the T-cell response to the pancreatic autoantigen insulinoma-associated protein 2 and to significantly delay disease transfer by pathogenic CD4(+)CD25(-) cells. Thus, a short treatment of adult NOD mice with an analog of 1,25-dihydroxyvitamin D(3) inhibits IL-12 production, blocks pancreatic infiltration of Th1 cells, enhances CD4(+)CD25(+) regulatory cells, and arrests the progression of type 1 diabetes, suggesting its possible application in the treatment of human autoimmune diabetes.  相似文献   
80.
Uptake of biocytin and biotin was investigated in cultured transformed variants of neuronal (NB2a neuroblastoma) and glial (C6 astrocytoma) CNS cells. NB2a cells took up both compounds but biocytin was transported more efficiently than biotin in the nanomolar concentration range. In NB2a cells a single transport mechanism was found for biocytin with different kinetic parameters in the presence of high extracellular Na+ (Km 0.4 microM, Vmax 20 pmol/min/mg), K+ (Km 1.7 microM, Vmax 32 pmol/min/mg), or choline+ (Km 0.1 microM, Vmax 5 pmol/min/mg). Two transport systems (Km1 17 microM, Vmax1 53 pmol/min/mg; Km2 314 microM, Vmax2 360 pmol/min/mg) were identified for biotin with only system 1 being Na+-dependent. Biocytin uptake was competitively inhibited by excess biotin but not vice versa. Inhibition studies with structural analogs indicated different specificities for biotin and biocytin uptake. Biocytin uptake into C6 cells was hardly detectable whereas biotin was taken up by diffusion (kD 0.6 microl/min/mg) and a single saturable mechanism (Km 70 microM, Vmax 119 pmol/min/mg) at high extracellular Na+. High extracellular K+ enhanced biotin diffusion into C6 cells. Inhibition studies with structural analogs revealed a less specific biotin uptake mechanism in C6 than in NB2a cells. Biocytin normalized deficient biotin-dependent propionyl-CoA carboxylase activity within 4 h in biotin-deficient NB2a cells whereas in C6 cells reactivation was <20% thereby confirming that biocytin is only poorly transported into C6 cells. Specific biocytin uptake into NB2a cells is to our knowledge the first demonstration of a carrier-mediated transport mechanism for this compound. Neuronal biocytin uptake might contribute to the pathogenesis of biotinidase deficiency where biocytin is present in elevated levels.  相似文献   
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