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1.
Paolo Ambrosetto Stefano Zucchini Alessandro Cicognani Emanuele Cacciari 《Pediatric radiology》1998,28(5):288-289
A girl with Diamond-Blackfan syndrome and hypopituitarism was suspected of having pituitary haemosiderosis because of the
clinical picture and the long history of blood transfusions. On T1-weighted MR images the pituitary exhibited a markedly hypointense
anterior lobe (mimicking the empty sella), suggesting iron deposition, while on T2W MRI the low signal of the pituitary was
surrounded by the high signal of the CSF. MR may be considered the examination of choice for detecting iron overload in the
pituitary.
Received: 10 November 1997 Accepted: 21 November 1997 相似文献
2.
Tiziano Dall'Occo Franco Sartori Giancarlo Vecellio Umberto Zucchini Andrea Maldotti 《Macromolecular chemistry and physics.》1993,194(1):151-161
As a part of our interest in the performance of [Ti2(OC2H5)8Cl]2Mg2(μ-Cl)2 as Ziegler-Natta catalyst, the polymerization of styrene with a toluene solution of this compound and methyl-aluminoxane as cocatalyst was performed. It was found that the present catalytic system promotes the syndiospecific polymerization of styrene with high stereoregularity and the results were compared with those obtained with MgCl2-supported or unsupported Ti(OC2H5)4 catalysts. Determination of the titanium oxidation states and electron spin resonance (ESR) measurements both in the absence and in the presence of styrene were carried out for all the catalytic systems aimed at shedding some light on the nature of the active species. 相似文献
3.
Decreased levels of neuropeptide Y(5) receptor binding sites in two experimental models of epilepsy 总被引:2,自引:0,他引:2
It has been suggested that the anticonvulsant effects of neuropeptide Y (NPY) could be mediated by the activation of Y(2) and/or Y(5) receptors. NPY Y(1) receptor levels are known to decrease and Y(2) to increase in rat models of epilepsy. By using an autoradiographic approach, we investigated whether epilepsy models (kainic acid and kindling) are also associated with changes in Y(5) receptors. Compared with naive controls, [125I][Leu(31), Pro(34)]PYY/BIBP3226-insensitive (Y(5)) binding sites in the hippocampus (strata oriens and radiatum of CA3 and CA1) and in the neocortex (superficial layers) were unchanged in sham-stimulated rats, but reduced by approximately 50% in kindled rats (seven days after the last stimulus evokes seizure), and further reduced (to approximately -90%) 1h after a kindled seizure. Additionally, Y(5) receptor binding sites in the hippocampus and in the neocortex were unchanged 6h after kainic acid injection, but were highly reduced at 12 and 24h. No changes in Y(5) binding levels were found in the dentate gyrus and the pyramidal cell layer of the hippocampus.The present data suggest that changes in Y(5) receptor levels occur in epilepsy models. These changes may play a role in seizure expression and/or in the maintenance of kindling hyperexcitability. 相似文献
4.
Aldo Becciolini Manuela Balzi Paola Faraoni Elena Tisti Giorgia Zappoli Thyrion Valentino Giach Luca Bandettini Christopher S. Potten 《Acta oncologica (Stockholm, Sweden)》1998,37(1):65-71
Cell kinetics parameters have been analysed in colonic mucosa at different distances from a tumour in patients with colon carcinoma. Total cell number (TCN), H thymidine labelling index (TLI), mitotic index (MI), Goblet cell index (GCI) and the distribution of labelled cells along the crypt column (cell position frequency plot) were determined in well-aligned crypts. Total cell number, GCI and the labelled cell position frequency plots were similar in different samples from the same individual. A negative linear correlation between TCN and TLI was observed. The analysis of the cell position plots showed two patterns 1) with a high concentration in the bottom fifth of the crypt and 2) with frequent labelled cells at high positions. Whereas a negative correlation between overall TLI and the percent contribution to the TLI of the lowermost fifth was seen, the correlation was positive for the next 3 fifths and labelling was absent in the last part of the crypt. 相似文献
5.
BACKGROUND AND PURPOSE: To appraise the potential benefit of a conformal technique with non-coplanar fields to minimise lung irradiation in the radiation treatment of breast. PATIENTS AND METHODS: A comparative study was carried out at planning level for six patients selected for their inadequate sparing of healthy lung tissue with the reference tangential technique. Plans were designed for the conventional tangential technique, for an alternative conformal approach with three beams and for the newly proposed technique with two non-coplanar beams. RESULTS: In average for the new technique compared to the reference, mean lung dose dropped from approximately 16 to 10.5 Gy, V(20 Gy) from 29.5 to 18.2% and the dose delivered to 1/3 (1/4) of the lung volume dropped from 28.5% (67.3%) to 8.7% (13.4%). For PTV, the volume receiving at least 90% of the prescribed dose resulted 97.4% for the new and 97.3% for the reference. Conformity index improved significantly from 2.58 for the reference to 1.84 for the new technique. CONCLUSIONS: For a subgroup population of breast cancer patients, where conventional techniques failed to achieve high conformal avoidance, a treatment modality with non-coplanar beams was developed and clinically tested for six patients. It resulted dosimetrically adequate, particularly when the risk of toxicity is relevant. 相似文献
6.
Jason Doran Nabil Seyidov Samir Mehdiyev Giorgia Gon Esther Kissling Trent Herdman Javahir Suleymanova Ana Paula Couthino Rehse Richard Pebody Mark A. Katz Gahraman Hagverdiyev 《Influenza and other respiratory viruses》2022,16(4):626
IntroductionWe evaluated uptake and factors associated with COVID‐19 vaccination among health workers (HWs) in Azerbaijan.ResultsAmong 1575 HWs, 73% had received at least one dose, and 67% received two doses; all received CoronaVac. Factors associated with vaccination uptake included no previous COVID‐19 infection, older age, belief in the vaccine''s safety, previous vaccination for influenza, having patient‐facing roles and good or excellent health by self‐assessment.ConclusionThese findings could inform strategies to increase vaccination uptake as the campaign continues. 相似文献
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Lorna A. Brudie Giorgia Gaia Sarfraz Ahmad Neil J. Finkler Glenn E. Bigsby IV Giselle B. Ghurani James E. Kendrick IV Joseph A. Rakowski Jessica H. Groton Robert W. Holloway 《Journal of robotic surgery》2012,6(4):317-322
We analyzed peri-operative outcomes of 80 patients who underwent robotic-assisted laparoscopic surgery and were diagnosed with stage IV endometriosis (revised American Society for Reproductive Medicine) between January 2007 and December 2010 at a tertiary gynecologic oncology referral center with a fellowship training program. Eligible women had a combination of one or more factors: pelvic mass, sub-acute or chronic pelvic pain, dysmenorrhea, dyspareunia, elevated serum CA-125, diagnosed with stage IV endometriosis at surgery with robotic-assisted gynecologic procedures using the da Vinci? Surgical System. The mean age was 43.7?±?7.0?years, body mass index 27.5?±?7.4?kg/m2, and 23 (28.9%) patients had prior endometriosis surgery. Presenting symptoms included: chronic pelvic pain (48.8%), dysmenorrhea (40.3%), and dyspareunia (33.8%). Sixty-nine (86%) patients had pelvic masses (43 unilateral and 26 bilateral). Thirty-seven (46.3%) had elevated CA-125 levels (mean 97.9?±?71.6 U/ml). Forty-eight (60%) underwent robotic-assisted laparoscopic hysterectomy (RALH)/bilateral salpingo-oophorectomy (BSO), 9 (11.3%) RALH/unilateral salpingo-oophorectomy (USO), 5 (6.3%) modified radical hysterectomy, and 10 (13%) USO or BSO only. Four (5%) had ovarian cystectomies with excision of endometriotic implants. Three (3.8%) underwent appendectomy and no patient required bowel resection. Four (5%) patients required conversion to laparotomy during the first 15 cases of this series [dense adhesions (3) and ureteral injury (1)]. Mean operative time was 115?±?46?min, blood loss 88?±?67?ml, and length of stay 1.0?±?0.4?days. There were four (5%) complications (ureteral injury, cuff abscess, cuff hematoma, re-admission for nausea and vomiting secondary to narcotics) and no transfusions. One (1.3%) patient underwent a second surgery for pain (dyspareunia). Robotic-assisted surgery for stage IV endometriosis resulted in excellent pain relief, with few laparotomy conversions or complications during a robotic learning-curve experience. 相似文献