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991.
Research literature supports the notion that more people diagnosed with schizophrenia are born during the winter months than other seasons [O'Hare A, Walsh D, Torrey F. Seasonality of schizophrenia births in Ireland. Br J Psychiatry 1980;137:74 7; Pulver AE, Stewart W, Carpenter WT, Jr., Childs B. Risk factors in schizophrenia: season of birth in Maryland, USA. Br J Psychiatry 1983;143:389-96.]. Researchers have postulated that this surge in winter-birth schizophrenia may be related to increases in viral infectious such as influenza and measles [Watson CG, Kucala T, Tilleskjor C, Jacobs L. Schizophrenic birth seasonality in relation to incidence of infectious diseases and temperature extremes. Arch Gen Psychiatry 1984:41:85-90; Mednick SA, Machon RA, Huttunen MO, Bonnett D. Adult schizophrenia following prenatal exposure to an influenza epidemic. Arch Gen Psychiatry 1988;45:189-92.]. However, data supporting significant relationships between infectious disease and schizophrenia incidence has been equivocal [Kendell R, Kemp I. Maternal influenza in the etiology of schizophrenia. Arch Gen Psychiatry 1989;46:878-82; McGrath J, Castle D. Does influenza cause schizophrenia? A five year review. Aust N Z J Psychiatry 1995;29:23-31.]. The purpose of this study was to replicate and expand previous studies by examining seasonal and infectious disease influences on schizophrenia prevalence. It was hypothesized that: (1) there would be an increase in schizophrenia prevalence during the winter months; and (2) that a significant amount of variability in schizophrenia birthrates would be accounted for by rates of influenza and measles. A Georgia Medicaid database (N = 746,615) and statewide infectious disease tables were used to identify correlations. Medicaid recipients were divided into schizophrenia (n = 11,736) and non-schizophrenia (n = 734,879) groups. A ratio of schizophrenic recipients to non-schizophrenic recipients was calculated for each birth cohort represented by each month of the year from 1948-1965. Multiple regression analyses indicated a significant relationship between winter season and schizophrenia incidence. However, neither influenza nor measles was predictive of schizophrenia prevalence. These findings were made using one of the largest sample of schizophrenic individuals in the literature to date. Limitations of the study are discussed, including the use of seasonal and prevalence correlations without data on patient linked maternal infections. 相似文献
992.
Background. Omental infarction has been previously reported in the adult surgical and imaging literature; however, the imaging features
of this entity in children have received little attention. Objective. The purpose of our study was to identify the sonographic features of omental infarction in nine children who had preoperative
sonography and surgically proven omental infarction. Materials and methods. Sonographic images were reviewed and correlated with clinical information obtained from the patients' medical records, including
clinical presentation, operative notes, and pathology reports. Results. In seven of the children, sonography demonstrated a focal area of moderately increased echogenicity in the omental fat in
the right abdomen (a previously described finding in omental infarction). This was an isolated finding in four of these cases.
In the three cases where this was not an isolated finding, the more complex sonographic appearance led to incorrect preoperative
imaging diagnoses. This finding of increased echogenicity in the omental fat was not present in the two remaining patients.
Conclusion. Our study confirms that foci of moderately increased echogenicity in the omentum of the right abdomen, a sonographic finding
described in omental infarction in a large series in adults (and in a single prior case report in children), can be seen in
children as well. However, although this is a relatively unique finding, it may be absent in some cases or may be seen in
conjunction with other sonographic findings which may preclude the correct preoperative sonographic diagnosis.
Received: 9 December 1998 Accepted: 31 March 1999 相似文献
993.
The classification of cartilaginous tumors of the skull base, including chondroid chordoma and chondrosarcoma remains the subject of controversy. Critical review of the literature and our own experience of chordomas and cartilaginous tumors of the skull base led to the following conclusions: 1) Chondrosarcoma of the skull base is a distinct clinicopathological entity. The immunohistochemical staining pattern (cytokeratin negative, epithelial membrane antigen (EMA) negative) can be helpful in distinguishing it from chordoma with chondroid differentiation (cytokeratin positive, EMA positive). 2) The chondroid chordomas originally described by Heffelfingeret al. may have included some true chondrosarcomas with focal areas of myxoid chordomalike appearance. 3) Focal chondroid differentiation in chordoma is not such a rare phenomenon. Further study is needed to define whether chordoma with chondroid foci should be separated out from conventional chordoma as a distinct entity with a better prognosis. 相似文献
994.
Marck P Coleman-Miller G Hoffman C Horsburgh B Woolsey S Dina A Dorfman T Nolan J Jackson N Kwan JA Hagedorn K 《Nursing leadership (Toronto, Ont.)》2007,20(3):42-51
As leaders for nursing education, nursing research, healthcare administration and patient safety, we asked one another: How do we use our collective resources to build health system capacity for clinically based research training and safer healthcare? Drawing on knowledge from the field of ecological restoration, which is the study and repair of damaged ecosystems, we partnered the Safer Systems research program of the Faculty of Nursing, University of Alberta, with Capital Health's Royal Alexandra Hospital (RAH), the Caritas Health Group, the Canadian Patient Safety Institute (CPSI) and several funding agencies to provide hands-on training in clinical research, infection control and patient safety policy development for nursing students during the summer months. As we plan ahead, our student and staff evaluations show that together, we can make concrete, vital contributions to student education, nursing research, evidence-informed practice, clinical quality improvement and national policy. We are using what we have learned to continually expand the range of undergraduate, graduate and post-doctoral clinical learning opportunities in healthcare safety that are available year round. Our shared goal is to support current and future nurses in leading the way for safer healthcare systems and the safest possible healthcare. 相似文献
995.
I.?SukhotnikEmail author Y.?Ben?Shahar Y.?Pollak T.?Dorfman H.?Kreizman?Shefer Z.?E.?Assi N.?Mor-Vaknin A.?G.?Coran 《Pediatric surgery international》2018,34(2):217-225
Purpose
Intermediate filaments (IFs) are a part of the cytoskeleton that extend throughout the cytoplasm of all cells and function in the maintenance of cell-shape by bearing tension and serving as structural components of the nuclear lamina. In normal intestine, IFs provide a tissue-specific three-dimensional scaffolding with unique context-dependent organizational features. The purpose of this study was to evaluate the role of IFs during intestinal adaptation in a rat model of short bowel syndrome (SBS).Materials and methods
Male rats were divided into two groups: Sham rats underwent bowel transection and SBS rats underwent a 75% bowel resection. Parameters of intestinal adaptation, enterocyte proliferation and apoptosis were determined 2 weeks after operation. Illumina’s Digital Gene Expression (DGE) analysis was used to determine the cytoskeleton-related gene expression profiling. IF-related genes and protein expression were determined using real-time PCR, Western blotting and immunohistochemistry.Results
Massive small bowel resection resulted in a significant increase in enterocyte proliferation and concomitant increase in cell apoptosis. From the total number of 20,000 probes, 16 cytoskeleton-related genes were investigated. Between these genes, only myosin and tubulin levels were upregulated in SBS compared to sham animals. Between IF-related genes, desmin, vimentin and lamin levels were down-regulated and keratin and neurofilament remain unchanged. The levels of TGF-β, vimentin and desmin gene and protein were down-regulated in resected rats (vs sham animals).Conclusions
Two weeks following massive bowel resection in rats, the accelerated cell turnover was accompanied by a stimulated microfilaments and microtubules, and by inhibited intermediate filaments. Resistance to cell compression rather that maintenance of cell-shape by bearing tension are responsible for contraction, motility and postmitotic cell separation in a late stage of intestinal adaptation.996.
Theodorus M. J. van Bakel Kevin D. Lau Jennifer Hirsch-Romano Santi Trimarchi Adam L. Dorfman C. Alberto Figueroa 《Journal of cardiovascular translational research》2018,11(2):145-155
Computational fluid dynamics (CFD) is a modeling technique that enables calculation of the behavior of fluid flows in complex geometries. In cardiovascular medicine, CFD methods are being used to calculate patient-specific hemodynamics for a variety of applications, such as disease research, noninvasive diagnostics, medical device evaluation, and surgical planning. This paper provides a concise overview of the methods to perform patient-specific computational analyses using clinical data, followed by a case study where CFD-supported surgical planning is presented in a patient with Fontan circulation complicated by unilateral pulmonary arteriovenous malformations. In closing, the challenges for implementation and adoption of CFD modeling in clinical practice are discussed. 相似文献
997.
Desjardins A Gromeier M Herndon JE nd Beaubier N Bolognesi DP Friedman AH Friedman HS McSherry F Muscat AM Nair S Peters KB Randazzo D Sampson JH Vlahovic G Harrison WT McLendon RE Ashley D Bigner DD 《中华神经外科疾病研究杂志》2018,(4)
Background The prognosis of patients with recurrent World Health Organization(WHO)grade IV malignant glioma is dismal,and there is currently no effective therapy.We conducted a dose-finding and toxicity study in this population of patients,evaluating convection-enhanced,intratumoral delivery of the recombinant nonpathogenic polio-rhinovirus chimera(PVSRIPO).PVSRIPO recognizes the poliovirus receptor CD155,which is widely expressed in neoplastic cells of solid tumors and in major components of the tumor microenvironment.Methods We enrolled consecutive adult patients who had recurrent supratentorial WHO grade IV malignant glioma,confirmed on histopathological testing,with measurable disease(contrast-enhancing tumor of≥1 cm and≤5.5 cm in the greatest dimension).The study evaluated seven doses,ranging between 107 and 1010 50%tissue-culture infectious doses(TCID50),first in a dose-escalation phase and then in a dose-expansion phase.Results From May 2012 through May 2017,a total of 61 patients were enrolled and received a dose of PVSRIPO.Dose level-1(5.0×107TCID50)was identified as the phase 2 dose.One dose-limiting toxic effect was observed;a patient in whom dose level 5(1010TCID50)was administered had a grade 4 intracranial hemorrhage immediately after the catheter was removed.To mitigate locoregional inflammation of the infused tumor with prolonged glucocorticoid use,dose level 5 was deescalated to reach the phase 2 dose.In the dose-expansion phase,19%of the patients had a PVSRIPO-related adverse event of grade 3 or higher.Overall survival among the patients who received PVSRIPO reached a plateau of 21%(95%confidence interval,11 to 33)at 24 months that was sustained at 36 months.Conclusions Intratumoral infusion of PVSRIPO in patients with recurrent WHO grade IV malignant glioma confirmed the absence of neurovirulent potential.The survival rate among patients who receivedPVSRIPO immunotherapy was higher at 24 and 36 months than the rate among historical controls. 相似文献
998.
Herskovits AZ Lemire SJ Longtine J Dorfman DM 《American journal of clinical pathology》2008,130(5):796-804
Thrombotic disease is a significant cause of mortality and morbidity, with an estimated lifetime risk of greater than 10% in Western populations. One of the most common hereditary thrombophilias is the factor V Leiden mutation, which is identified with a screening assay for activated protein C (APC) resistance and confirmed by DNA analysis. In this study, we compared the commercially available Pefakit (Pentapharm, Basel, Switzerland) and Cryocheck (Precision BioLogic, Dartmouth, Canada) assays, 2 recently developed Russell viper venom (RVV)-based screening tests, with the activated partial thromboplastin time (aPTT)-based screening test currently used in our hospital's clinical laboratory. We found that the aPTT-based assay for resistance to APC had a sensitivity of 100%, a specificity of 70%, and a positive predictive value (PPV) of 70%, whereas both of the RVV-based assays exhibited high sensitivity, specificity, and PPV at 100%. In addition, we found that these new functional assays are more cost-effective relative to the screening algorithm previously used in our clinical laboratory and could potentially eliminate the need for DNA analysis, although further study is required. 相似文献
999.
Aggressive (epithelioid) osteoblastoma arising in soft tissue has never been described. It is important to differentiate this benign osteoblastoma, a potentially locally aggressive tumor, from extraskeletal osteosarcoma. This report describes an aggressive (epithelioid) osteoblastoma arising in a focus of heterotopic ossification in the axilla of a 21-year-old man. 相似文献
1000.