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81.
Supplementation with Citrulline (Cit) has been shown to have a positive impact on aerobic exercise performance and related outcomes such as lactate, oxygen uptake (VO2) kinetics, and the rate of perceived exertion (RPE), probably due to its relationship to endogenous nitric oxide production. However, current research has shown this to be controversial. The main objective of this systematic review and meta-analysis was to analyze and assess the effects of Cit supplementation on aerobic exercise performance and related outcomes, as well as to show the most suitable doses and timing of ingestion. A structured literature search was carried out by the PRISMA® (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and PICOS guidelines in the following databases: Pubmed/Medline, Scopus, and Web of Science (WOS). A total of 10 studies were included in the analysis, all of which exclusively compared the effects of Cit supplementation with those of a placebo group on aerobic performance, lactate, VO2, and the RPE. Those articles that used other supplements and measured other outcomes were excluded. The meta-analysis was carried out using Hedges’ g random effects model and pooled standardized mean differences (SMD). The results showed no positive effects of Cit supplementation on aerobic performance (pooled SMD = 0.15; 95% CI (−0.02 to 0.32); I2, 0%; p = 0.08), the RPE (pooled SMD = −0.03; 95% CI (−0.43 to 0.38); I2, 49%; p = 0.9), VO2 kinetics (pooled SMD = 0.01; 95% CI (−0.16 to 0.17); I2, 0%; p = 0.94), and lactate (pooled SMD = 0.25; 95% CI (−0.10 to 0.59); I2, 0%; p = 0.16). In conclusion, Cit supplementation did not prove to have any benefits for aerobic exercise performance and related outcomes. Where chronic protocols seemed to show a positive tendency, more studies in the field are needed to better understand the effects.  相似文献   
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Salivary gland lesions are uncommon in children and may be related to the parotid, submandibular or sublingual glands. Inflammatory lesions are the most common cause of salivary gland abnormalities in children and can be due to acute viral, acute suppurative, or recurrent acute or chronic inflammation. Intraparotid lymphadenitis may also occur, as in cat-scratch disease or in other causes of cervical lymphadenitis. Salivary gland neoplasms are rare in children, and most of them are benign including mainly hemangioma, pleomorphic adenoma, or lymphangioma. Other lesions, such as sialolithiasis, mucocele, or ranula, may also be seeen. Ultrasonography should be the initial imaging study used for the examination of salivary gland lesions in children, given the fact that most of such lesions are benign and are shown up clearly by sonography. In most cases, this technique permits the differentiation of intraglandular and extraglandular lesions, and may suggest the correct diagnosis. The entire lesion could not be totally depicted by US however, and other imaging techniques such as CT or MRI may be necessary. Vascular lesions can be demonstrated more clearly through the use of color Doppler imaging. Some of the lesions may appear similar, and clinical correlation is important for the differential diagnosis. This article discusses the sonographic appearance and clinical manifestations of the spectrum of salivary gland abnormalities that may occur in children. Received: 3 September 1997 Accepted: 31 December 1997  相似文献   
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One of the main problems of our health care system is its excessive use. The most evident results of this misuse are the waste of resources and the iatrogenic consequences that are not justified by any expectations in health improvement. Among the possible causes of this inappropriate use, the trivialization of medical practice should be emphasized. This entails not only a loss of respect and consideration, but facilitates and even stimulates reckless use. Although patients and health care workers are both responsible for this recklessness, politicians and health care managers should be held responsible more so. Without a real emancipation allowing health care users and the population to control the factors that determine their health, it is unlikely that the inappropriate use of health resources and its associated iatrogenic consequences will be reduced.  相似文献   
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Polarized Fourier transform-infrared (FT-IR) was used to compare the orientation of vibrational chemical groups of bovine tendon collagen bundles (CBs) to that of nylon 6, a simpler polyamide model, in terms of linear dichroism (LD). Subtraction of spectral profiles identified the most significant differences regarding the amide regions. At 1630 cm−1, the CBs displayed higher peak areas and absorbance when positioned perpendicularly (A) to the plane of polarized light, in comparison with nylon 6. In contrast, at the 1526 cm−1 amide II spectral region the inverse occurred. In the amide III region (1232 cm−1), the LD was positive and higher for CBs. Dichroic ratios (DR = A||/A) calculated from the average of ten measured spectra for CBs and nylon 6 revealed that the values for CBs were <1.0 in the 3298–1655 cm−1 wavenumber range and >1.0 in the 1536–1234 cm−1 wavenumber range. From 1535 to 1120 cm−1, nylon 6 displayed DR values higher than those of CBs. The LD band integrated areas were higher in CBs than in nylon 6. The LD differences between CBs and nylon 6 are probably due to a more complex chemical composition and supramolecular oriented architecture in CBs in comparison to nylon 6.  相似文献   
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Introduction

Communication between pulp and periodontal tissue has been well established. However, it is unknown when periodontal disease begins to affect the clinical response of pulp tissue. The aim of this study was to assess the influence of periodontal severity on pulp sensibility by means of electric and thermal cold testing.

Methods

The teeth assessed in this study were allocated into 3 groups considering radiographic alveolar bone loss (ABL) as follows: slight periodontitis (SP, ABL ≤7 mm without reaching the apex, n = 25), moderate periodontitis (ABL >7 mm without reaching the apex, n = 23), and severe periodontitis (SvP, ABL >7 reaching the apex, n = 8). Gingival recession (GR), probing depth (PD), and clinical attachment level (CAL) were also measured.

Results

The results showed higher levels of PD and CAL in the SvP group compared with the SP group (P < .05), with no significant difference in GR (P > .05). The SvP group showed significant ABL compared with the other groups (P > .05). The SP group showed a significant number of teeth with a positive pulp response, whereas the SvP group showed a significant number of teeth with a negative pulp response (P < .05); no significant differences were observed between the thermal cold and electric tests (P > .05).

Conclusions

Within the limits of this study, it can be concluded that pulp clinical involvement with a negative response to thermal cold and electric testing occurs only in the most advanced stage of chronic periodontitis with apical involvement.  相似文献   
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