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91.
Hypophosphatemic rickets/osteomalacia in linear sebaceous nevus syndrome: a variant of tumor-induced osteomalacia 总被引:1,自引:0,他引:1
D E Carey M K Drezner J A Hamdan M Mange M S Ahmad S Mubarak W L Nyhan 《The Journal of pediatrics》1986,109(6):994-1000
A severe form of vitamin D-resistant rickets is associated with the linear sebaceous nevus syndrome. We investigated the pathophysiology underlying defective bone mineralization in two individuals and examined the effects of 1,25-dihydroxyvitamin D (1,25(OH)2D, calcitriol) therapy on the clinical and biochemical abnormalities. Both patients had fasting hypophosphatemia, markedly diminished TmP/GFR, and elevated alkaline phosphase activity in the presence of normocalcemia. Before treatment with calcitriol, serum 1,25(OH)2D concentrations were reduced but serum 25-hydroxyvitamin D (25(OH)D) concentrations were normal. Administration of calcitriol increased serum 1,25(OH)2D concentrations and led to an increase in TmP/GFR and serum phosphorus levels and to a decrease in alkaline phosphatase activity. However, the renal tubular maximum for reabsorption of inorganic phosphate, normalized according to glomerular filtration rate, and serum phosphorus levels remained abnormally low even in the patient who also received phosphate supplementation. Bone histomorphologic studies in the adult patient showed extreme osteomalacia, which partially improved with calcitriol. These data demonstrate that the putative skin lesion-derived factor results in both a renal tubular defect in phosphate reabsorption and in 1,25-(OH)2 D deficiency. The vitamin D-resistant rickets of linear sebaceous nevus syndrome is a variant of tumor-induced osteomalacia. 相似文献
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Purpose:This study aims to facilitate researchers’ and clinicians’ understanding of research frontiers and trends in nocturia. It explores the scientific research outcomes and key bibliometric indices and plots global research on nocturia.Methods:A bibliometric retrospective study was designed, and an online search was conducted in the Web of Science Core Collection database using the potential search keywords related to nocturia in the title field with some specific filtration. HistCite™ and VOSviewer software for windows were used to analyze the data obtained for authors, journals, countries, institutions, keywords, and visualization mapping.Results:The initial search retrieved 1479 hits. A total of 1445 publications were included in the final analysis. Of these, 43.53% were published as articles. The most studied area in nocturia is urology nephrology. The most productive year was 2019 (n = 121, citations = 335), and the most prolific author, both in terms of publications (n = 97) and citations (1658) was Weiss JP. The most cited journal in nocturia research was the Journal of Urology (n = 293, citations = 3050). The most widely used keyword in nocturia publications was nocturia (n = 1249). Visualization mapping shows that the USA was the most influential and highly cited country in nocturia research.Conclusion:This study showed that there has been an increasing research trend in nocturia over the past few years. The current findings provide important empirical evidence for researchers, clinicians, and physicians to understand research frontiers and trends, achievements, collaborative networks, and hotspot research topics in the research field of nocturia. 相似文献
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IntroductionThe glans penis is prone to mutilation in a handful of conditions, some accidental and others iatrogenic. Deformed functioning remnants of the glans challenge the surgeon's decision. Neither is the glans totally amputated, justifying a neoglansplasty, nor are the remnants cosmetically acceptable, though retaining sensibility and engorgement.AimIn this work, we described the “reconfiguration of the glans penis” whereby deformed glanular tissue remnants can be made into a functional and cosmetically acceptable glans.MethodsFive patients with separate mutilated lumps of functioning glanular tissue were operated upon. The lumps were mobilized and flattened into sheets and configured to redrape the summit of the penis, minding their vascular and nerve supply.Main Outcome MeasuresCosmetic and functional outcome.ResultsThe outcome was cosmetically acceptable for all patients in comparison to the preoperative state.ConclusionGlans reconfiguration may possibly confer an acceptable cosmetic outlook to a mutilated glans without compromising valuable functional characteristics. Shaeer O, El-Sebaie A, Sherif A, El-Sadat A, and Shaeer A. Glans reconfiguration for management of glanular mutilation. 相似文献
97.
Abdel Bar FM Zaghloul AM Bachawal SV Sylvester PW Ahmad KF El Sayed KA 《Journal of natural products》2008,71(10):1787-1790
Three new 28-norlupane triterpenes, 28-norlup-20(29)-en-3beta-hydroxy-17beta-hydroperoxide (1), 28-norlup-20(29)-en-3beta-hydroxy-17alpha-hydroperoxide (2), and 20 S-17beta,29-epoxy-28-norlupan-3beta-ol (3), were isolated from the leaves of Melaleuca ericifolia along with eight known pentacyclic triterpenes. The structures of the new compounds were elucidated by spectroscopic methods including 1D and 2D NMR spectroscopy and mass spectrometry. The isolated triterpenes were evaluated for antiproliferative activity against the malignant +SA mammary epithelial cell line. 相似文献
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Abdullah Alhendal Randa Abd Almoaeen Mohamed Rashad Ali Husain Fouzi Mouffouk Zahoor Ahmad 《RSC advances》2022,12(28):18077
This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network. To overcome the inherent shortcomings of the CNTs'' solubility and dispersion in both organic phases and in the sol–gel solution, the outer surface of the CNTs was initially functionalized with carboxylic acid groups and then reacted with both aramid oligomers and 3-aminopropyl triethoxysilane (APTES). The obtained sorbent was characterized by FT-IR, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Using sol–gel chemistry, the functionalized CNTs were coated onto SPME fibers and used in conjunction with GC-MS for the analysis of polycyclic aromatic hydrocarbons (PAHs) in water and soil samples. Excellent repeatability (run-to-run RSD% ∼ 8) and reproducibility (fiber-to-fiber RSD% ∼ 6) were achieved in addition to low LODs (0.10–0.30 ng mL−1) and noticeable recovery%. The present method of sorbent preparation led to enhanced thermal and chemical stabilities, a long sorbent lifetime and good affinity towards PAHs. Moreover, the present sorbent enhanced the extraction capability by more than 30% compared to that of commercially available PDMS counterparts.This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network. 相似文献
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Ahmad Salawi 《Drug delivery》2022,29(1):1811
Self-emulsifying drug delivery systems (SEDDS) are a proven method for poorly soluble substances works by increasing the solubility and bioavailability. SEDDS and isotropic mixtures, are composed of oils, surfactants, and occasionally cosolvents. The ability of these formulations and methods to produce microemulsions or fine oil-in-water (o/w) emulsions after moderate stirring and dilution by water phase along the GI tract might be a promising technique for lipophilic agents with dissolution rate-limited absorption. This review provides an outline of SEDDS''s numerous advances and biopharmaceutical elements, types, manufacturing, characterization, limitations, and future prospects. The evaluation of SEDDS and its applications are also discussed, focusing on the advances of SEDDS''s solid self-emulsifying delivery mechanism and dosage form. By integrating suitable polymer into the formulation, SEDDS may be studied for the creation of a formulation with sustained drug release. This technology''s improvement might lead to a new application in the field of medicine delivery. SEDDS has been demonstrated to be quite efficient in increasing oral bioavailability of lipophilic products. SEDDS is one of the promising methods for controlling the characteristics of medications that are not great choices for oral delivery. It is also worth mentioning that SEDDS may be made in variety of solid dosage forms that are acceptable for both oral and parenteral administration. 相似文献