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91.
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Bone width and mineral content were measured in 420 healthy Cambridge children aged 4 to 10 years using single photon absorptiometry. The results are expressed first in the form of standard centile charts, with additional prediction charts which provide body-size-adjusted estimates for the measurements, and interpretation centiles for comparing these estimates with the actual measurements. The values obtained are similar to those reported for American children aged five to six years after adjusting for body-size differences. We suggest that appropriate application of these prediction charts will facilitate the use of single photon absorptiometry in monitoring and treating children who have disorders of bone growth and mineralization.  相似文献   
93.
The elemental composition of the freshwater clam,Anodonta cygnea, was investigated in response to exposure to cadmium at 50 ppb (g/L) Cd during 12 weeks. Accumulation of cadmium affected the composition in various tissues and hemolymph. From 2 to 8 weeks of exposure considerable loss of sodium occurred, to about half the levels in control animals. During the last four weeks of exposure, sodium concentrations stabilized at the decreased level while those of potassium started to decline. Minor changes were noticeable for other elements. Calcium and iron tended to increase in all organs examined while magnesium levels remained constant. Zinc increased slightly during exposure to cadmium. For some elements, especially zinc and sulphur, hemolymph concentrations showed a response opposite to those in tissues. Concentrations of Al, B, Ba, Be, Ce, Co, Cr, Cu, Li, Mn, Mo, Ni, P, Pb, Sn, Sr, Ti, V, Y, and Zr did not change during Cd exposure. Possible sites of cadmium interaction with ionic regulation are discussed.  相似文献   
94.
Freshwater clams (Anodonta cygnea) were exposed to Cd2+ (25 g/L) or to Cd2+ (25 g/L) plus Zn2+ (2.5 mg/L). In the presence of zinc, uptake of cadmium in whole clam was halved. In organs such as the gills, mantle, and labial palps a still larger reduction of Cd accumulation occurred. By contrast, accumulation in midgut gland and kidney was hardly affected by the presence of zinc. It is shown that in the gills zinc competes with cadmium for metal binding sites both within the particulate fraction and the high-molecular weight fraction of the cytosol. Zinc probably did not induce an enlarged synthesis of specific metal-binding, metallothionein-like, proteins. In conclusion, zinc exerts antagonistic effects on uptake of cadmium by gills, and accelerates Cd transport from the gills towards the internal organs.  相似文献   
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Atrial septal defects are associated with significant morbidity and mortality. Echocardiography is the first‐line imaging modality, but MR and CT imaging can provide complimentary information, especially for the detection of associated anomalies and for assessing changes in the pulmonary vasculature. The aim of this pictorial essay is to review the spectrum of atrial septal defects, with particular reference to their cross‐sectional imaging appearances and issues pertaining to management.  相似文献   
97.
Objectives Injectable poly‐l ‐lactic acid (PLLA; Sculptra®) is widely used throughout Europe and the USA to restore volume in depressed areas of the face by stimulating neocollagenesis. Injectable PLLA was previously marketed as New‐Fill™, which was often injected incorrectly and at too high a concentration, resulting in some physicians losing confidence in this product. Today, Sculptra® is still regarded with a degree of scepticism by some physicians, due to direct or indirect experience with New‐Fill. Sculptra®, both in formulation and use, is vastly superior to New‐Fill and clinical experience with this product dispels the myths associated with the earlier types of injectable PLLA. Results PLLA is a very safe, biodegradable compound that has been used in a wide range of medical devices for the last 30 years. In injectable form a good safety profile has been proven; however, when the device is overconcentrated, localized overstimulation of the fibroblasts can result in the formation of small lumps (subcutaneous papules), which are non‐pathological but nevertheless palpable by the patient. Physicians must also be trained in the injection of this device, as incorrect injection technique can cause device‐related adverse events. Conclusion New product guidelines have ensured that problems with PLLA concentration have been countered, and tried and tested injection techniques have been shown to ameliorate device‐related adverse events, both of which are dispelling the myths associated with modern injectable PLLA.  相似文献   
98.
Lymphangiomas are uncommon congenital lesions of the lymphatic system which usually present in childhood. We report a case of adult lymphangioma, localised in the neck, and discuss the presentation, diagnosis and management of this tumour.  相似文献   
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Costa  TCS  Fernandez-Villalba  E  Izura  V.  Lucas-Ochoa  AM  Menezes-Filho  NJ  Santana  RC  de Oliveira  MD  Araújo  FM  Estrada  C  Silva  VDA  Costa  SL  Herrero  MT 《Journal of neuroimmune pharmacology》2021,16(2):390-402

Inflammation is a predominant aspect of neurodegenerative diseases and experimental studies performed in animal models of Parkinson’s disease (PD) suggesting that a sustained neuroinflammation exacerbates the nigrostriatal degeneration pathway. The central role of microglia in neuroinflammation has been studied as a target for potential neuroprotective drugs for PD, for example nonsteroidal anti-inflammatory drugs (NSAIDs) and matrix metalloproteinases (MMP) inhibitors that regulates microglial activation and migration. The aim of this study was to investigate the neuroprotective response of the iminosugar 1-deoxynojirimycin (1-DNJ) and compare its effect with a combined treatment with ibuprofen. MPTP-treated mice were orally dosed with ibuprofen and/or 1-DNJ 1. Open-field test was used to evaluate behavioral changes. Immunohistochemistry for dopaminergic neurons marker (TH+) and microglia markers (Iba-1+; CD68+) were used to investigate neuronal integrity and microglial activation in the substantia nigra pars compacta (SNpc). The pro-inflammatory cytokines TNF-α and IL-6 were analysed by qPCR. Treatments with either 1-DNJ or Ibuprofen alone did not reduce the damage induced by MPTP intoxication. However, combined treatment with 1-DNJ and ibuprofen prevents loss of mesencephalic dopaminergic neurons, decreases the number of CD68+/ Iba-1+ cells, the microglia/neurons interactions, and the pro-inflammatory cytokines, and improves behavioral changes when compared with MPTP-treated animals. In conclusion, these data demonstrate that the combined treatment with a MMPs inhibitor (1-DNJ) plus an anti-inflammatory drug (ibuprofen) has neuroprotective effects open for future therapeutic interventions.

MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) is a protoxicant that, after crossing the Blood Brain Barrier, is metabolized by astrocytic MAO-B to MPDP+, a pyridinium intermediate, which undergoes further two-electron oxidation to yield the toxic metabolite MPP+ (methyl-phenyltetrahydropyridinium) that is then selectively transported into nigral neurons via the mesencephalic dopamine transporter. In this study, we demonstrated that MPTP induced death of dopaminergic neurons, microgliosis, increase of gliapses, motor impairment and neuroinflammation in mice, which were inhibited by combined 1-deoxynojirimycin and ibuprofen treatment.

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