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11.
Six children presenting with partial growth hormone (GH) deficiency (mean GH peak in two different tests, 8.0 k1.3 μ g/l ) aged 8–10.3 years (mean, 2.7 ± 0.9 years) were treated for 6 months by continuous subcutaneous infusion of GH-releasing hormone(1–29)-NH, (GHRH(1–29)-NH2); 24-hour GH profiles and height velocity were measured. A biphasic effect of GHRH(1–29)-NH2 infusion was observed. After an early substantial increase in the 24-hour integrated concentration of GH, from 1.6 ± 0.1 to 3.5 ± 0.7 μg/l/minute, a subsequent consistent decrease occurred by 3 months, which was more pronounced after 6 months (mean 24-hour integrated concentration of GH, 1.9± 0.9 μg/l/minute). This effect reflects modification of both pulse amplitude and frequency of GH secretion. At the end of the study, one child had complete suppression of GH secretion and two others showed only one peak above 5 μg/1 during a 24-hour period. No correlation was found between these changes and height velocity. Three children did not grow significantly; the other three children who had a growth response to GHRH(1–29)-NH2 were those with the lowest 24-hour integrated GH concentration at the end of the study. The possible mechanisms involved in this biphasic effect, including GHRH antibodies, changes in somatostatin levels and/or desensitization of pituitary GHRH receptors, have been investigated.  相似文献   
12.
Moderate and severe malnutrition are endemic in much of the developing world and in association with pockets of deprivation in the developed world. The cost in terms of individual and social development is high. The principles of effective management are clearly documented. A low cost, community based treatment programme for moderately and severely malnourished children under 3 years of age was established at a health centre in rural Jamaica. Children were followed up monthly and defaulters were rigorously recalled. Management consisted of carefully delivered dietary advice, antibiotics, anthelminthics, and vitamin supplements. All children improved and the response of 36 children, who were treated in the first year, showed an accelerated weight gain, with catch-up growth and the maintenance of length gain. There was a significant increase in the weight for age, at 1.9% per month over six months, which exceeds the rate reported with food supplementation programmes and nutrition rehabilitation centres.  相似文献   
13.
The use of follow up studies was evaluated in 128 patients with coeliac disease during their first visit to a department for adults. The original diagnosis had been made in childhood in all patients. Fifty eight (45%) of the subjects were following a gluten free diet, 23 (18%) were following a gluten free diet but with occasional gluten consumption, and 47 (37%) had adopted an unrestricted, gluten containing diet for a mean of 11.2 years. There was no correlation in individual subjects between the presence of symptoms, biochemical and immunological abnormalities, severity of histological findings, and the amount of dietary gluten, despite the greater frequency of symptoms in the group following an unrestricted diet than in the other two groups. Short stature and epilepsy with cerebral calcifications only occurred in patients following an unrestricted diet. As only diagnosis based on two or three biopsy samples and regular follow up correlated positively with dietary compliance, it is suggested that a histologically confirmed diagnosis of coeliac disease and regular lifelong follow up are essential in the management of these patients.  相似文献   
14.
Xi  L; Zhang  L; Wang  Y; Smith  MT 《Carcinogenesis》1997,18(9):1687-1693
1,3-Butadiene is a carcinogen in rodents, but its potential carcinogenicity to humans remains controversial. Numerous studies have shown that butadiene and its metabolites cause sister chromatid exchanges in vitro and in vivo. To test for other types of genotoxicity, the micronucleus assay and fluorescence in situ hybridization (FISH) have been used to detect chromosome damage in human lymphocytes caused by two reactive metabolites of butadiene, diepoxybutane (DEB) and monoepoxybutene (MEB). DEB (0.5-5.0 microM) significantly increased micronucleus formation 4- to 6-fold (P <0.01) and MEB (1-500 microM) by 2- to 4-fold (P <0.01) over control levels. The ability of DEB and MEB to induce aneuploidy of chromosomes 7, 8, 12, and X was examined using dual-color FISH in both interphase and metaphase cells. These chromosomes were chosen because of their involvement in leukemogenesis. Both DEB and MEB caused dose-dependent increases in hyperdiploidy of chromosomes 12 and X, but had no discernible effect on chromosomes 7 and 8. These results suggest that DEB and MEB cause chromosome-specific aneuploidy in human cells. If formed in sufficient amounts, DEB and MEB may produce chromosome damage of the type found in leukemia following exposure to butadiene.   相似文献   
15.

Introduction

The application of a final irrigating solution that remains active over a fairly long period of time stands as one strategy for preventing bacterial recolonization or eliminating the bacteria that persist after root canal treatment. The aim of this study was to evaluate the residual antimicrobial activity of four final irrigation regimens in root canals contaminated with Enterococcus faecalis.

Methods

Biofilms of E. faecalis were grown in uniradicular roots for 4 weeks. After preparing the roots chemomechanically, four final irrigation regimens were applied: (1) group EDTA-NaOCl, 17% EDTA followed by 5.25% sodium hypochlorite (NaOCl); (2) group MA-NaOCl, 7% maleic acid (MA) followed by 5.25% NaOCl; (3) group EDTA-CHX + CTR, 17% EDTA followed by 2% chlorhexidine (CHX) + 0.2% cetrimide (CTR); and (4) group MA-CHX + CTR, 7% MA followed by 2% CHX + 0.2% CTR. Samples were collected for 60 days to denote the presence of bacterial growth. The Fisher exact test was used to compare the percentages of specimens without E. faecalis regrowth.

Results

All root canals in which the final irrigant was 5.25% NaOCl yielded positive cultures on the fifth day. Groups EDTA-CHX + CTR and MA-CHX + CTR with a final irrigation of 2% CHX + 0.2% CTR showed respective percentages of samples without regrowth of 72.1% and 66.8% at 60 days. There were no statistically significant differences between these groups.

Conclusions

The combination of 2% CHX + 0.2% CTR would be an effective alternative final irrigation regimen given its antimicrobial action over time.  相似文献   
16.

INTRODUCTION

In 2004, an audit in our unit demonstrated wide variation in liver resection rates for colorectal cancer (CRC) metastases within the cancer network. Subsequently, a network-wide CT-based follow-up and referral policy was introduced for all patients. A second audit was performed to assess the impact of the guidelines on liver resection rates.

SUBJECTS AND METHODS

Analysis of prospective liver resection database between 1997 and 2004 and after the introduction of standardised guidelines between January 2005 and April 2008.

RESULTS

A total of 362 patients underwent liver resection for CRC metastases between 1997 and 2008, 237 prior to the introduction of the referral guidelines and 125 after. Liver resection rates according to referring hospital varied from 0.92 to 2.32 per 100,000 population before guidelines were introduced. After 2005, resection rates from the four district hospitals standardised (1.68–1.84 per 100,000 population), but the central unit rate (Sheffield) remained significantly higher (2.67 per 100,000 population). No significant difference in 1-year disease-free survival between patients from Sheffield and the outlying hospitals was found (P = 0.553).

CONCLUSIONS

Introduction of a referral protocol standardised resection rates from the four district hospitals, but these remain lower compared to the specialist centre. The wide-spread adoption of a policy to discuss all patients with liver metastases at an advanced disease multidisciplinary team meeting, in the presence of hepatobiliary specialists, may further increase resection rates across the UK.  相似文献   
17.
18.
19.

Objective

Adherence problems are a common feature among bipolar patients. A recent study showed that lithium knowledge was the main difference between adherent and non adherents bipolar patients. The Lithium Knowledge Test (LKT), a brief questionnaire, was developed as a means of identifying aspects of patients' practical and pharmacological knowledge which are important if therapy is to be safe and effective. The original English version is validated in psychiatric population, but a validated Portuguese one is not yet available.

Methods

One hundred six patients selected were diagnosed with bipolar disorder (I or II) according to DSM-IV criteria and had to be on lithium treatment for at least one month. The LKT was administered on only one occasion. We analysed the internal consis tency, concurrent validity, sensitivity and specificity of the LKT for the detection of the knowledge about lithium treatment of bipolar patients.

Results

The internal consistency, evaluated by Cronbach's alpha was 0.596. The mean of total score LKT by bipolar patients was 9.0 (SD: 0.75) for men and 8.74 (SD: 0.44) for women. Concurrent validity based on plasma lithium concentration showed a significant correlation between the total LKT score and plasma lithium (r = 0,232; p = 0.020). The sensitivity was 84% and specificity was 81%.

Conclusion

LKT is a rapid, reliable instrument which appears to be as effective as a lengthier standard interview with a lithium clinic doctor, and which has a high level of acceptability to lithium patients. We found that the psychometric assessment of the Portuguese version of LKT showed good internal consistency, sensitivity and specificity.
  相似文献   
20.

Background

Preprocedure clinical and pathologic factors have failed to consistently differentiate complete response (CR) from progressive disease (PD) in patients after isolated limb infusion (ILI) with melphalan for unresectable in-transit extremity melanoma.

Methods

Multiplex immunobead assay technology (Milliplex MAP Human Cytokine/Chemokine Magnetic Bead Panel, Millipore Corp., Billerica, MA; and Magpix analytical test instrument, Luminex Corp., Austin, TX) was performed on pre-ILI plasma to determine concentrations of selected cytokines (MIP-1α, IL-1Rα, IP-10, IL-1β, IL-1α, MCP-1, IL-6, IL-17, EGF, IL-12p40, VEGF, GM-CSF, and MIP-1β) on a subset of patients (n = 180) who experienced CR (n = 23) or PD (n = 24) after ILI. Plasma from normal donors (n = 12) was also evaluated.

Results

Of 180 ILIs performed, 28 % (95 % confidence interval 22–35, n = 50) experienced a CR, 14 % (n = 25) experienced a partial response, 11 % (n = 21) had stable disease, 34 % (n = 61) had PD, and 13 % (n = 23) were not evaluable for response. Tumor characteristics and pharmacokinetics appeared similar between CR (n = 23) and PD (n = 24) patients who underwent cytokine analysis. Although there were no differences in cytokine levels between CR and PD patients, there were differences between the melanoma patients and controls. MIP-1α, IL-1Rα, IL-1β, IL-1α, IL-17, EGF, IL-12p40, VEGF, GM-CSF, and MIP-1β were significantly higher in normal controls compared to melanoma patients, while IP-10 was lower (p < 0.001) in controls compared to melanoma patients.

Conclusions

Patients with unresectable in-transit melanoma appear to have markedly decreased levels of immune activating cytokines compared to normal healthy controls. This further supports a potential role for immune-targeted therapies and immune monitoring in patients with regionally advanced melanoma.  相似文献   
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