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81.
Steroid sulphatase deficiency is a feature of recessive X-linked ichthyosis (RXLI) that causes the accumulation of sulphated steroids (SS) in various organs and cells. In a previous study, we detected elevated cholesterol sulphate (CS) and dehydroepiandrosterone sulphate (DHEAS) serum levels in a group of 15 RXLI patients selected in a narrow age range. In the present study both CS and DHEAS serum levels were qualitatively and quantitatively determined using gas-chromatographic analysis in a group of 33 RXLI patients ranging in age from 3 to 70 years. The levels of CS and DHEAS were significantly increased in all patients. Variations in SS were related both to patients' ages and clinical course of the disease. Serum SS levels start to increase in early infancy, peak at puberty, remain elevated in adults and decrease slightly in the elderly.  相似文献   
82.
The haemodialysis patients are an high risk population for hepatitis viral infections. While the incidence of HBV has decreased worldwide, HCV is now the major cause of viral infection in these patients. The aim of our study was to define a complete map of patients undergoing routine replacement therapy by haemodialysis in the province of Foggia, Southern Italy, who were HCV Ab positive, the presence of viraemia and their genotypes; moreover, we investigated the probable factors involved in determining the infection as well as the means of prevention. Materials and methods: We enrolled 330 patients treated in four haemodialysis centres (DC) and six secondary units; mean age was 57 years and mean duration of dialysis 76 months. Samples were drawn to determine cytolysis indexes and the HCV Ab status; in HCV positive patients, we also looked for viraemia and HCV genotypes. Data were analysed by a transversal cross-section study. Results and conclusions: Prevalence of HCV infection was 0.43 (males 0.45, females 0.42). The risk of contracting the infection was shown to be significantly different in the various DCs and did not seem to be related to the severity of the preventive measures. There was no significant difference between the various DCs in the comparison between the odds of HCV-RNA+ and HCV-RNA– patients. No significant prevalence of a given genotype emerged from a cross-sectional study related to the comparison between different genotypes. Moreover, transfusions of blood products seemed to have no significant relation to HCV infection. Finally, patients treated with haemodialysis for more than 36 months run a seven time greater risk of contracting HCV infection.  相似文献   
83.
Populations of the temperate seagrass, Zostera marina L. (eelgrass), often exist as discontinuous beds in estuaries, harbors, and bays where they can reproduce sexually or vegetatively through clonal propagation. We examined the genetic structure of three geographically and morphologically distinct populations from central California (Elkhorn Slough, Tomales Bay, and Del Monte Beach), using multilocus restriction fragment length polymorphisms (DNA fingerprints). Within-population genetic similarity (Sw) values for the three eelgrass populations ranged from 0.44 to 0.68. The Tomales Bay population located in an undisturbed, littoral site possessed a within-population genetic similarity (Sw = 0.44) that was significantly lower than those of the other two populations. Cluster analysis identified genetic substructure in only the undisturbed subtidal population (Del Monte Beach). Between-population similarity values (Sb) for all pairwise comparisons ranged from 0.47 to 0.51. The three eelgrass populations show significantly less between locale genetic similarity than found within populations, indicating that gene flow is restricted between locales even though two of the populations are separated by only 30 km. The study demonstrates that (i) natural populations of Z. marina from both disturbed and undisturbed habitats possess high genetic diversity and are not primarily clonal, (ii) gene flow is restricted even between populations in close proximity, (iii) an intertidal population from a highly disturbed habital shows much lower genetic diversity than an intertidal population from an undisturbed site, and (iv) DNA fingerprinting techniques can be exploited to understand gene flow and population genetic structure in Z. marina, a widespread and ecologically important species, and as such are relevant to the management of this coastal resource.  相似文献   
84.
Melatonin, a potent free radical scavenger, plays an important role in homeostasis of cell and organ physiology. The increased demand and synthesis from the pineal gland during times of oxidative stress suggests a potential benefit of melatonin supplementation during hospitalization for acute illness. Yet, the paucity of clinical studies for non-anesthetic–associated indications in pediatric populations hampers the safe, effective, and consistent use of melatonin. The objective of this study was to systematically review published studies of melatonin use for non-sedative and non-analgesic indications in hospitalized pediatric patients. We conducted a search of PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science, and Scopus databases for articles on the use of melatonin for pediatric patients in a hospital setting. Thirteen eligible studies, all in neonates, were identified. Data elements extracted included study design, number of study subjects, indication for melatonin therapy, and melatonin regimen (formulation, dosage, and duration). Because study methodologies were very heterogeneous, a quantitative synthesis of the published findings was not possible. The identified studies were therefore categorized by the indication of melatonin (adjuvant-antioxidant or anti-inflammatory therapy) in the following specific disease states: (i) acute infections, (ii) respiratory distress syndrome, (iii) neurologic injury, and (iv) jaundice. The current data suggest that melatonin is safe for use in hospitalized neonates. Melatonin may be beneficial for reducing inflammatory markers in neonatal patients with disease states and clinical sequelae that are associated with increased inflammation and oxidative stress. Melatonin, in conjunction with phototherapy, is not superior to use of vitamin D with phototherapy for treatment of neonatal jaundice. However, studies in other pediatric populations are needed given widespread use across clinical inpatient settings.  相似文献   
85.
Sinus of Valsalva aneurysms are extremely rare with a predominance in the Asian population. The clinical presentation may be ambiguous, depending on which sinus is affected and on the conditions of the lesion. We report a case of a 33-year-old patient with Down syndrome. Ambulatory transthoracic and transesophageal echocardiography both show a mass located in the right atrium presumed to be of mixomatous nature. Intraoperative transesophageal echocardiography and surgical exploration lead to the diagnosis of sinus of Valsalva aneurysm.  相似文献   
86.
87.
BACKGROUND: The aim of the present randomized, double-masked, clinical trial was to compare platelet-rich plasma (PRP) combined with a demineralized freeze-dried bone allograft (DFDBA) to DFDBA mixed with a saline solution in the treatment of human intrabony defects. METHODS: Sixty interproximal intrabony osseous defects in 60 healthy, non-smoking subjects diagnosed with chronic periodontitis were treated in this study. Thirty subjects each were randomly assigned to the test group (PRP + DFDBA) or the control group (DFDBA + saline). Clinical and radiographic measurements were made at baseline and at the 12-month evaluation. RESULTS: Compared to baseline, the 12-month results indicated that both treatment modalities resulted in significant changes in all clinical parameters (gingival index, bleeding on probing, probing depth, clinical attachment level, and gingival recession; P <0.001) and radiographic parameters (hard tissue fill and bone depth reduction; P <0.001). However, the test group exhibited statistically significantly greater changes compared to the control group in probing depth reduction (4.3 +/- 1.7 mm versus 2.6 +/- 2.2 mm; P <0.05) and clinical attachment gain (3.5 +/- 2.1 mm versus 2.3 +/- 2.4 mm; P <0.001). CONCLUSIONS: Treatment with a combination of PRP and DFDBA led to a significantly greater clinical improvement in intrabony periodontal defects compared to DFDBA with saline. No statistically significant differences were observed in the hard tissue response between the two treatment groups, which confirmed that PRP had no effect on hard tissue fill or gain in new hard tissue formation.  相似文献   
88.
89.
Motor disorders are an important chapter in esophageal pathology; from a clinical point of view, these disorders are characterised by dysphagia, non-cardiac chest pain, pyrosis and regurgitation. It is important to underline that chest pain and dysphagia are not specific to motility disorders; in fact, they are also present in other pathologies like peptic or infective esophagitis. In order to attribute these symptoms to a functional cause, it is first of all is necessary to exclude an organic pathology; this can be done with the help of radiological and endoscopical examination when the symptoms are dysphagia, pyrosis and regurgitation, or with electrocardiography or angiography, when the symptom is chest pain. The functional pathology is marines studied by manometric and pH-metric techniques. The manometric technique represents an important instrument for diagnosing esophageal motor disease. The aim of this study, after a review of the literature, is to describe the principal esophageal motor disorders and the physiopathological approach, that have important implications in diagnosis and therapy.  相似文献   
90.
Summary The functional state of beta cells may influence the rate of their destruction in Type 1 (insulin-dependent) diabetes mellitus. We examined the effect of diazoxide, which inhibits insulin secretion, or tolbutamide, which stimulates insulin secretion, upon the incidence of diabetes in the non-obese-diabetic (NOD) mouse. Female mice were treated from 3–30 weeks of age with diet containing diazoxide 250 mg·kg−1 or tolbutamide 125 mg·kg−1. The cumulative incidence of diabetes at 35 weeks was similar in the diazoxide (16 of 24) and control (18 of 24) groups, but reduced in the tolbutamide group (10 of 23,p<0.04 vs control group). In a second experiment, treatment was started from 9 weeks of age, by which time insulitis is already present. The cumulative incidence of diabetes at 35 weeks was 16 of 24 in controls, 15 of 24 on diazoxide and 11 of 24 on tolbutamide (p=NS vs control). A third experiment compared the effect of treatment from 3 weeks with control diet or diet containing tolbutamide 125 mg·kg−1 or 500 mg·kg−1. Diabetes was reduced by tolbutamide treatment, with a cumulative incidence of 25 of 31 in controls, 18 of 30 on tolbutamide 125 mg·kg−1 (p<0.04) and 14 of 32 on 500 mg·kg−1 (p<0.002), although the difference between the two treatment groups failed to reach statistical significance. A fourth experiment showed that treatment from 3–12 weeks with diazoxide 1000 mg·kg−1 increased the extent of insulitis compared with controls and animals treated with tolbutamide 500 mg·kg−1. Elucidation of the mechanisms by which tolbutamide reduces the incidence of diabetes in the NOD mouse has implications for human intervention trials.  相似文献   
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