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71.
Multiple Endocrine Neoplasia type 1 is an autonomic dominant disease with a high degree of penetrance. It is characterized by combinations of over 20 different endocrine and nonendocrine tumors. A 25-year-old woman was referred for 1 year-evolution amenorrhea and bilateral galactorrhea. She also had fasting hypoglycaemia and hypercalcemia, and she was diagnosed of Multiple Endocrine Neoplasia type 1A. Resection of three parathyroid glands was performed showing hyperplasia of principal cells. Post-parathyroidectomy serum levels of calcium and intact PTH were normal but 3 years later serum calcium levels rose again. A 99mTc-sestamibi scan showed increased uptake in the low right area compatible with adenoma. After biochemical test showing probable insulinoma, somatostatin receptor scintigraphy showed a focal captation in head and body of pancreas. MRI found two nodules in the same localization. An antral gastrectomy, total pancreatoduodenectomy, colecistectomy and truncal vagotomy was performed and histopathologic examination revealed a combination of neuroendocrine tumors: gastrinomas, somastotinomas, glucagonomas and insulinomas. After surgery she started with tingling in fingers, toes and lips, and calcium levels was 5.9 mg/dl and PTH intact 3 pg/ml. A new 99m Tc-sestamibi scan showed no captation and cervical ultrasonography was normal. Now, 2 years later, she continues with normal calcium and i-PTH levels. This report represents an unusual case of MEN 1A with association of insulinomas, gastrinomas glucagonomas and somatostatinomas in the same patient.  相似文献   
72.
Fluorescent silica nanoparticles (NPs–(SiO2–Fluo)) were synthesized based on the classical Störber method for cyanobacteria labelling. Modified mono-coloured SiO2 NPs with fluorescein (Fl) and rhodamine B (RhB) were obtained (NPs–(SiO2–Fl) and NPs–(SiO2–RhB)). Moreover, multi-coloured SiO2 NPs, via the incorporation of both emitters (NPs–(SiO2–RhB–Fl)), were tuned for optimal emissions and the biodetection of cyanobacteria. NPs–(SiO2–Fl) and NPs–(SiO2–RhB–Fl) were optimized for detection via laser fluorescence microscopy and in-flow cytometry with laser excitation and fluorescence detection. By TEM, homogeneous SiO2 NPs of 180.0 nm in diameter were recorded. These sizes were slightly increased due to the covalent linking incorporation of fluorescent dye emitters to 210.0 nm with mono-coloured fluorescent modified amine-organosilanes, and to 340.0 nm in diameter with multi-coloured dye incorporation. NPs–(SiO2–Fluo) showed variable emission depending on the dye emitter concentration, quantum yield and applied luminescent pathway. Thus, mono-coloured NPs–(SiO2–Fl) and NPs–(SiO2–RhB) showed diminished emissions in comparison to multi-coloured NPs–(SiO2–RhB–Fl). This enhancement was explained by fluorescence resonance energy transfer (FRET) between Fl as a fluorescent energy donor and RhB as an energy acceptor produced within the nanoarchitecture, produced only in the presence of both fluorophores with the appropriate laser excitation of the energy donor. The depositions of the nano-emitters on cyanobacteria by non-covalent interactions were observed by TEM and laser fluorescence microscopy. For multi-coloured NPs–(SiO2–RhB–Fl) labelling, bio-FRET was observed between the emission of the nano-labellers and the natural fluorophores from the cyanobacteria that quenched the emission of the whole nano-biostructure in comparison to mono-coloured NPs–(SiO2–Fl) labelling. This fact was explained and discussed in terms of different fluorescence energy transfer from the nanolabellers towards different natural chromophore coupling. In the presence of NPs–(SiO2–RhB–Fl) and NPs–(SiO2–RhB), the emission was coupled with lower quantum yield chromophores; while upon the application of NPs–(SiO2–Fl), it was coupled with higher quantum yield chromophores. In this manner, for enhanced luminescent nanoplatform tracking, the multi-coloured NPs–(SiO2–RhB–Fl) showed improved properties; but more highly luminescent bio-surfaces were generated with mono-coloured NPs–(SiO2–Fl) that permitted faster cyanobacteria detection and counting by laser fluorescence microscopy, and by in-flow cytometry with laser excitation and fluorescence detection.

Fluorescent silica nanophotonics for cyanobacteria labelling.  相似文献   
73.
Tantalum oxide is ubiquitous in everyday life, from capacitors in electronics to ion conductors for electrochromic windows and electrochemical storage devices. Investigations into sol–gel deposition of tantalum oxide, and its sister niobium oxide, has accelerated since the 1980s and continues to this day. The aim of this study is to synthesize a near UV sensitive, air stable, and low toxicity tantalum sol–gel precursor solution for metal oxide thin films – these attributes promise to reduce manufacturing costs and allow for facile mass production. By utilizing 1D and 2D nuclear magnetic resonance, this study shows that by removing ethanol from the precursor solution at a relatively low temperature and pressure, decomposition of the photosensitive complex can be minimized while obtaining a precursor solution with sufficient stability for storage and processing in the atmosphere. The solution described herein is further modified for inkjet printing, where multiple material characterization techniques demonstrate that the solution can be utilized in low temperature, photochemical solution deposition of tantalum oxide, which is likely amorphous. Tested substrates include amorphous silica, crystalline silicon wafer, and gold/titanium/PET foil. The hope is that these results may spark future investigations into electronic, optical, and biomedical device fabrication with tantalum oxide, and potentially niobium oxide, based films using the proposed synthesis method.

Synthesis of tantalum(v) 1,3-propanediolate β-diketonate solution and use in photochemical solution deposition to form tantalum oxide films.  相似文献   
74.
75.
International Journal of Mental Health and Addiction - The presence of COVID-19 has had psychological consequences among health personnel; these include fear, anxiety, and depression. In the...  相似文献   
76.
As runners age, the likelihood of developing osteoarthritis (OA) significantly increases as 10% of people 55+ have symptomatic knee OA while 70% of people 65+ have radiographic signs of knee OA. The lateral-medial shear force (LMF) and knee adduction moment (KAM) during gait have been associated with cartilage loading which can lead to OA. Foot rotation during gait has been shown to alter the LMF and KAM, however it has not been investigated in running. The purpose of this study was to investigate changes in the KAM and LMF with foot rotation during running. Twenty participants volunteered and performed five running trials in three randomized conditions (normal foot position [NORM], external rotation [EXT], and internal rotation [INT]) at a running speed of 3.35m·s-1 on a 20 meter runway. Kinematic and kinetic data were gathered using a 9-camera motion capture system and a force plate, respectively. Repeated measures ANOVAs determined differences between conditions. The KAM and LMF were lower in both EXT and INT conditions compared to the NORM, but there were no differences between EXT and INT conditions. The decreases in KAM and LMF in the EXT condition were expected and concur with past research in other activities. The reductions in the INT condition were unexpected and contradict the literature. This may indicate that participants are making mechanical compensations at other joints to reduce the KAM and LMF in this abnormal internal foot rotation condition.

Key points

  • External rotation of the foot during running reduced the loads on the medial compartment of the knee
  • Internal rotation of the foot also reduced the medial loads, but is a more unnatural intervention
  • External and internal rotation reduced the shear forces on the knee, which may help slow the degeneration of knee joint cartilage
Key words: Osteoarthritis, cartilage, biomechanics, gait  相似文献   
77.
OBJECTIVE: Over a 70-month period, 100 consecutive Mexican mestizo individuals with a clinical marker associated with a primary hypercoagulable state were studied. METHODS: We prospectively assessed: the sticky platelet syndrome (SPS), the activated protein C resistance (aPCR) phenotype, coagulation protein C activity and antigen, coagulation protein S, antithrombin III, plasminogen, IgG and IgM isotypes of antiphospholipid antibodies, homocysteine levels, the factor V gene Leiden, Cambridge, Hong Kong, and Liverpool mutations, the 677 C-->T mutation in the 5,10-methylenetetrahydrofolatereductase (MTHFR), and the G20210A polymorphism in the 3'-untranslated region of the prothrombin gene. RESULTS: Of the 100 consecutive patients prospectively accrued in the study, only 29% were males. In only 6 individuals could we not record any abnormality, whereas in most individuals (81%), two to five co-existing abnormalities were identified. In a multivariate analysis of the association of all these assesments, the only significant association was found between the factor V Leiden mutation and the aPCR phenotype (r = .495; p < 0.001). CONCLUSIONS: These results confirm previous observations on thrombophilia in Mexico underlining that it is a multifactorial disease. They also suggest that the abnormalities detected are not associated to each other.  相似文献   
78.
The present study evaluated the efficacy of Familias Unidas + Parent-Preadolescent Training for HIV Prevention (PATH), a Hispanic-specific, parent-centered intervention, in preventing adolescent substance use and unsafe sexual behavior. Two hundred sixty-six 8th-grade Hispanic adolescents and their primary caregivers were randomly assigned to 1 of 3 conditions: Familias Unidas + PATH, English for Speakers of Other Languages (ESOL) + PATH, and ESOL + HeartPower! for Hispanics (HEART). Participants were assessed at baseline and at 6, 12, 24, and 36 months postbaseline. Results showed that (a) Familias Unidas + PATH was efficacious in preventing and reducing cigarette use relative to both control conditions; (b) Familias Unidas + PATH was efficacious, relative to ESOL + HEART, in reducing illicit drug use; and (c) Familias Unidas + PATH was efficacious, relative to ESOL + PATH, in reducing unsafe sexual behavior. The effects of Familias Unidas + PATH on these distal outcomes were partially mediated by improvements in family functioning. These findings suggest that strengthening the family system, rather than targeting specific health behaviors, may be most efficacious in preventing and/or reducing cigarette smoking, illicit drug use, and unsafe sex in Hispanic adolescents.  相似文献   
79.
Genetic disorders of bone constitute a large number of alterations approaching almost 300 types. This article focuses on the most common disorders in this group, which at the same time are the most clinically significant because of their incidence and degree of involvement of the craniofacial skeleton.  相似文献   
80.
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