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11.
Jasbir S. Johal James W. Thorp Calvin E. Oyer 《Pediatric and developmental pathology》1998,1(5):433-437
We report a neonate with neonatal hemochromatosis (NH), renal tubular dysgenesis (RTD), and hypocalvaria. NH is a fatal condition
of the newborn, characterized by severe idiopathic liver failure of intrauterine onset and siderosis, intra- and extrahepatic,
with sparing of the reticuloendothelial system. RTD is characterized by short, abnormally developed cortical tubules that
lack proximal tubule differentiation. Although both NH and RTD have been reported as entities with a genetic component, similar
findings can be secondary to in utero insults. Hypocalvaria has been reported in association with fetal hypoxia including
that secondary to angiotensin converting enzyme inhibitors. This 38-week-old infant died at 8.5 h. The small nodular liver
weighed 44 g. Grossly, the kidneys were normal. Hypocalvaria was present. Microscopically, the hepatic parenchyma was distorted
by fibrous tracts, proliferation of bile ducts, and abundant iron deposition in hepatocytes. Extrahepatic siderosis in the
pancreas, myocardium, and other organs was consistent with NH. Proximal convoluted tubules were not seen on routine stains
and markers for proximal tubules were negative. Previous reports have linked NH with RTD and RTD with hypocalvaria. This infant
had all three of these rare conditions, which have been hypothesized or shown to be due to genetic factors, hypoxia, or drugs.
The etiology in this case is unknown.
Received May 20, 1997; accepted August 15, 1997. 相似文献
12.
Takayuki Fujii Masao Hagihara Keiko Mitamura Shiori Nakashima Shin Ohara Tomoyuki Uchida Morihiro Inoue Moe Okuda Atsuhiro Yasuhara Jurika Murakami Calvin Duong Kiyoko Iwatsuki-Horimoto Seiya Yamayoshi Yoshihiro Kawaoka 《Internal medicine (Tokyo, Japan)》2022,61(11):1681
Objective Coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread globally. Although the relationship between anti-SARS-CoV-2 immunoglobulin G (IgG) antibodies and COVID-19 severity has been reported, information is lacking regarding the seropositivity of patients with particular types of diseases, including hematological diseases. Methods In this single-center, retrospective study, we compared SARS-CoV-2 IgG positivity between patients with hematological diseases and those with non-hematological diseases. Results In total, 77 adult COVID-19 patients were enrolled. Of these, 30 had hematological disorders, and 47 had non-hematological disorders. The IgG antibody against the receptor-binding domain of the spike protein was detected less frequently in patients with hematological diseases (60.0%) than in those with non-hematological diseases (91.5%; p=0.029). Rituximab use was significantly associated with seronegativity (p=0.010). Conclusion Patients with hematological diseases are less likely to develop anti-SARS-CoV-2 antibodies than those with non-hematological diseases, which may explain the poor outcomes of COVID-19 patients in this high-risk group. 相似文献
13.
Oocytes inseminated by intracytoplasmic sperm injection using fresh ejaculated or freeze-dried rhesus macaque sperm showed similar activation, sperm aster assembly, and male-female pronuclear apposition rates. 相似文献
14.
15.
John N. Sheagren Carmelita U. Tuazon Calvin Griffin Neville Padmore 《Arthritis \u0026amp; Rheumatology》1976,19(5):887-890
Sera from 55 parenteral drug abusers with endocarditis due to Staphylococcus aureus were assayed for the presence and titer of rheumatoid factor. Thirteen (24%) of the 55 patients with endocarditis had sera positive for rheumatoid factor at one point or another in their courses; only 2 (7%) of 30 noninfected drug users were found to be positive. It appeared that more severe cases, as evidenced by duration of fever after initiation of antibiotic therapy, were more likely to develop rheumatoid factor. 相似文献
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18.
Karen E. Hauer Calvin L. Chou Kevin H. Souza Duncan Henry Helen Loeser Christian Burke 《Teaching and learning in medicine》2013,25(4):284-290
Background: Optimal methods of preparing students for high-stakes standardized patient (SP) examinations are unknown. Purposes: The purpose is to compare the impact of two formats of a formative SP examination (Web-based vs. in-person) on scores on a subsequent high-stakes SP examination and to compare students' satisfaction with each formative examination format. Methods: Clustered randomized trial comparing a Web-based module versus in-person formative SP examination. We compared scores on a subsequent high-stakes SP examination and satisfaction. Results: Scores on the subsequent high-stakes SP examination did not differ between the two formative formats but were higher after the formative assessment than without (p < .001). Satisfaction was higher with the in-person than Web-based formative assessment format (4.00 vs. 3.62 on a 5-point scale, p = .01). Conclusions: Two formats of a formative SP examination led to equivalent improvement in scores on a subsequent high-stakes examination. Students preferred an in-person formative examination to online but were satisfied with both. 相似文献
19.
Fractionated proton beam radiotherapy for acoustic neuroma 总被引:2,自引:0,他引:2
Bush DA McAllister CJ Loredo LN Johnson WD Slater JM Slater JD 《Neurosurgery》2002,50(2):270-3; discussion 273-5
OBJECTIVE: This study evaluated proton beam irradiation in patients with acoustic neuroma. The aim was to provide maximal local tumor control while minimizing complications such as cranial nerve injuries. METHODS: Thirty-one acoustic neuromas in 30 patients were treated with proton beam therapy from March 1991 to June 1999. The mean tumor volume was 4.3 cm(3). All patients underwent pretreatment neurological evaluation, contrast enhanced magnetic resonance imaging, and audiometric evaluation. Standard fractionated proton radiotherapy was used at daily doses of 1.8 to 2.0 cobalt Gray equivalent: patients with useful hearing before treatment (Gardner-Robertson Grade I or II) received 54.0 cobalt Gray equivalent in 30 fractions; patients without useful hearing received 60.0 cobalt Gray equivalent in 30 to 33 fractions. RESULTS: Twenty-nine of 30 patients were assessable for tumor control and cranial nerve injury. Follow-up ranged from 7 to 98 months (mean, 34 mo), during which no patients demonstrated disease progression on magnetic resonance imaging scans. Eleven patients demonstrated radiographic regression. Of the 13 patients with pretreatment Gardner-Robertson Grade I or II hearing, 4 (31%) maintained useful hearing. No transient or permanent treatment-related trigeminal or facial nerve dysfunction was observed. CONCLUSION: Fractionated proton beam therapy provided excellent local control of acoustic neuromas when treatment was administered in moderate doses. No injuries to the Vth or VIIth cranial nerves were observed. A reduction in the tumor dose is being evaluated to increase the hearing preservation rate. 相似文献
20.
Danielle A. Bischof MD Yuhree Kim MD MPH Rebecca Dodson MD M. Carolina Jimenez Ramy Behman MD Andrei Cocieru MD Dan G. Blazer III FACS MD Sarah B. Fisher MD Malcolm H. Squires III MD MS David A. Kooby MD Shishir K. Maithel MD FACS Ryan T. Groeschl MD T. Clark Gamblin MD FACS Todd W. Bauer MD FACS Paul J. Karanicolas MD PhD Calvin Law MD MPH Fayez A. Quereshy MD MBA Timothy M. Pawlik MD MPH PhD FACS 《Annals of surgical oncology》2014,21(9):2941-2948