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101.
Light scattering from cervical cells throughout neoplastic progression: influence of nuclear morphology,DNA content,and chromatin texture 总被引:1,自引:0,他引:1
Drezek R Guillaud M Collier T Boiko I Malpica A Macaulay C Follen M Richards-Kortum R 《Journal of biomedical optics》2003,8(1):7-16
A number of noninvasive fiber optic optical technologies are under development for real-time diagnosis of neoplasia. We investigate how the light scattering properties of cervical cells are affected by changes in nuclear morphology, DNA content, and chromatin texture, which occur during neoplastic progression. We used a Cyto-Savant computer-assisted image analysis system to acquire quantitative nuclear features measurements from 122 Feulgen-thionin-stained histopathologic sections of cervical tissue. A subset of the measured nuclear features was incorporated into a finite-difference time-domain (FDTD) model of cellular light scattering. The magnitude and angular distribution of scattered light was calculated for cervical cells as a function of pathologic grade. The nuclear atypia strongly affected light scattering properties. The increased size and elevated DNA content of nuclei in high-grade lesions caused the most significant changes in scattering intensity. The spatial dimensions of chromatin texture features and the amplitude of refractive index fluctuations within the nucleus impacted both the angular distribution of scattering angles and the total amount of scattered light. Cellular scattering is sensitive to changes in nuclear morphology that accompany neoplastic progression. Understanding the quantitative relationships between nuclear features and scattering properties will aid in the development of noninvasive optical technologies for detection of precancerous conditions. 相似文献
102.
103.
STUDY OBJECTIVES: Very few studies have evaluated narcolepsy in Asian countries, outside of Japan. Our goal was to study narcolepsy at the genetic, clinical and pathophysiological level in Korea. DESIGN: Prospective study of consecutive patients and age matched controls. Clinical data ascertained from the Stanford Sleep Inventory, Polysomnography and MSLT data, as well as clinical notes. High resolution DRB1 and DQB1 typing in all subjects and studies of CSF hypocretin-1 was also evaluated in a subset of patients. PARTICIPANTS AND SETTING: 20 patients diagnosed at St. Vincent and Korea University Hospitals (Seoul, Korea). 21 Korean control subjects. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: For narcoleptic subjects, mean age was 28.2 years old and 45% were female. Mean BMI was 23.9+/-3.4 kg/m2, a significantly higher value than that expected in an age- and sex-matched sample (p<0.01). All patients had sleepiness and cataplexy while the prevalence of other symptoms ranged from 60-75%. All but 2 subjects were HLA-DR15 (DR2), DQB1*0602 positive (90%). This high DQB1*0602 percentage compared with 24% DQB1*0602 positivity in 21 control Koreans. Protective effects were observed for the DQB1*0601 and DRB1*0406 alleles, Hypocretin (orexin) CSF studies were also performed in 6 cataplectic subjects, all of which had undetectable CSF hypocretin levels. Two of these subjects had started narcolepsy less than 1 year before analysis yet had undetectable hypocretin levels. CONCLUSION: These results illustrate the similarity of narcolepsy-cataplexy in Korea in comparisons with other more studied populations. We also identified a new potential HLA protective subtype, HLA-DRB1*0406. 相似文献
104.
Mixed epithelial and stromal tumors of the kidney. A report of 22 cases 总被引:16,自引:0,他引:16
Michal M Hes O Bisceglia M Simpson RH Spagnolo DV Parma A Boudova L Hora M Zachoval R Suster S 《Virchows Archiv : an international journal of pathology》2004,445(4):359-367
Mixed epithelial and stromal tumor of the kidney (MESTK) is a recently described subset of renal neoplasm that tends to occur in middle-aged and older women and is characterized by a distinctive histological appearance. To further characterize this lesion, we report the clinicopathological and immunohistochemical features of 22 additional cases from our institutional files. Grossly, the tumors ranged in size from 1 cm to 14 cm (mean 6.7 cm), were well circumscribed but unencapsulated, and showed a cystic cut surface. The tumors were composed of a spindle cell proliferation that resembled ovarian stroma, as well as an epithelial component lining the cystic structures, which usually consisted of flat to hobnailed cells typical of collecting-duct epithelium. Areas displaying features of Müllerian differentiation were also documented in 6 cases, including epithelium of endometrioid, tubal, clear cell and squamous cell type as well as one case showing an architecture that closely resembled Müllerian adenofibroma and adenosarcoma. Follow-up in 14 patients (average 4.4 years) showed no evidence of recurrence or metastasis. We believe these tumors represent the renal counterpart of similar mixed epithelial and stromal neoplasms occurring in the biliary tract and pancreas, which is also characterized by cystic structures lined by epithelium, admixed with ovarian-type stroma. The differential diagnosis for these tumors includes cystic nephroma and cystic partially differentiated nephroblastoma, which we believe to represent clinically and morphologically distinct entities from MESTK. In particular, the distinction from cystic nephroma in adult male patients is emphasized, and two cases of this entity are included in the study for comparison. 相似文献
105.
Michele R Cooley Cheryl A Boyce 《Journal of clinical child and adolescent psychology》2004,33(2):210-215
Recognizing that researchers and clinicians are increasingly faced with assessing, treating, and studying ethnically, racially, and culturally diverse populations, one question is whether the appropriate tools exist. This special section aspires to advance the available assessment strategies that are appropriate for the treatment, prevention, and research of diverse children and adolescents with anxiety symptoms and disorders. This introduction presents an overview of anxiety and its disorders among multiethnic youth and identifies emerging challenges and opportunities in the assessment and treatment of anxiety symptoms and disorders among Asian American and Pacific Islander, Hispanic/Latino, African American, and European American children and adolescents within a sociocultural context. 相似文献
106.
Gabriele Piuri Monica Zocchi Matteo Della Porta Valentina Ficara Michele Manoni Gian Vincenzo Zuccotti Luciano Pinotti Jeanette A. Maier Roberta Cazzola 《Nutrients》2021,13(2)
Magnesium (Mg2+) deficiency is probably the most underestimated electrolyte imbalance in Western countries. It is frequent in obese patients, subjects with type-2 diabetes and metabolic syndrome, both in adulthood and in childhood. This narrative review aims to offer insights into the pathophysiological mechanisms linking Mg2+ deficiency with obesity and the risk of developing metabolic syndrome and type 2 diabetes. Literature highlights critical issues about the treatment of Mg2+ deficiency, such as the lack of a clear definition of Mg2+ nutritional status, the use of different Mg2+ salts and dosage and the different duration of the Mg2+ supplementation. Despite the lack of agreement, an appropriate dietary pattern, including the right intake of Mg2+, improves metabolic syndrome by reducing blood pressure, hyperglycemia, and hypertriglyceridemia. This occurs through the modulation of gene expression and proteomic profile as well as through a positive influence on the composition of the intestinal microbiota and the metabolism of vitamins B1 and D. 相似文献
107.
Jocelyn T. D. Kelly Elizabeth Colantuoni Courtland Robinson Michele R. Decker 《Health and human rights》2021,23(1):75
Both the fields of public health and that of human rights seek to improve human well-being, including through reducing and preventing all forms of violence, to help individuals attain the highest quality of life. In both fields, mathematical methods can help “visibilize” the hidden architecture of violence, bringing new methods to bear to understand the scope and nuance of how violence affects populations. An increasing number of studies have examined how residing in a conflict-affected place may impact one of the most pervasive forms of violence—intimate partner violence (IPV)—during and after conflict. This paper contributes to this effort by examining whether severe forms of IPV are associated with previous experience of political violence in one conflict-affected country: Liberia. Our findings indicate that living in a district with conflict fatalities increased the risk of IPV among women by roughly 60%. Additionally, living in a district with conflict fatalities increased the risk of a past-year injury from IPV by 50%. This analysis brings to light links between two of the most pervasive forms of violence—political violence and violence against women. The findings suggest that women residing in a district that is more highly affected by conflict, not only people experiencing direct trauma during conflict, may be at risk of increased violence long after peace is declared. These findings point to the need for targeted programs that address IPV postconflict. 相似文献
108.
Jos María Robaina-Bordn Cristina Carranza-Rodríguez Michele Hernndez-Cabrera Margarita Bolaos-Rivero Elena Pisos-lamo Nieves Jan-Snchez Araceli Hernndez-Betancor Laura Surez-Hormiga Jos Luis Prez-Arellano 《Emerging infectious diseases》2021,27(2):570
To document the epidemiology, clinical features, and outcomes of murine typhus patients in the Canary Islands (Spain), we analyzed data that were retrospectively collected for 16 years for 221 patients. Murine typhus in the Canary Islands is characterized by a high rate of complications (31.6%), mainly liver, lung, kidney or central nervous system involvement. 相似文献
109.
Vural Alperen Carobbio Andrea Luigi Camillo Ferrari Marco Rampinelli Vittorio Schreiber Alberto Mattavelli Davide Doglietto Francesco Buffoli Barbara Rodella Luigi Fabrizio Taboni Stefano Tomasoni Michele Gualtieri Tommaso Deganello Alberto Hirtler Lena Nicolai Piero 《Neurosurgical review》2021,44(5):2857-2878
Neurosurgical Review - Transorbital endoscopic approaches are increasing in popularity as they provide corridors to reach various areas of the ventral skull base through the orbit. They can be used... 相似文献
110.
Guido Grappiolo Carmine F. Bruno Mattia Loppini Michele Mercurio Davide Castioni Giorgio Gasparini Olimpio Galasso 《The Journal of arthroplasty》2021,36(3):1060-1066
BackgroundDespite promising results at the mid-term followup, several aspects of conversion of the fused hip to total hip arthroplasty (THA) remain controversial. The aim of this study was to evaluate clinical and radiological outcomes with a minimum 5-year followup in patients who underwent conversion of the fused hip to THA.MethodsFifty-seven patients (59 hips) were evaluated. The Harris Hip Score (HHS), range of motion (ROM), and the Visual Analogue Scale (VAS) were used to assess hip function and low back pain. Subjective satisfaction with surgery and the presence of the Trendelenburg sign was also evaluated. Radiological assessment was performed pre- and postoperatively to evaluate loosening and heterotopic ossification (HO).ResultsAfter a mean followup of 13.0 ± 6.2 years, HHS and VAS significantly improved from 46.0 ± 16.7 to 80.8 ± 18.8 and from 4.4 ± 1.5 to 2.1 ± 1.4 (both P < .001), respectively. Twenty-three patients (40.4%) had a positive Trendelenburg sign, and HOs were found in 29 cases (49.1%). An overall 29.8% complication rate was noted. Smoking habits and rheumatoid arthritis were predictive of Trendelenburg sign (P = .046 and P = .038, respectively). Implant survival rate as the end point was 98.7 ± 1.3% at 5 years, 92.4 ± 3.3% at 10 years, 82.1 ± 5.7% at 15 years, and 73.4 ± 8.0% at 20 and 25 years. A worse cumulative implant survival rate was noted in patients who underwent previous hip surgery, defined as any hip operation before fusion (P = .005).ConclusionConversion of the fused hip to hip arthroplasty provides high levels of hip functionality and satisfaction with surgery at long-term followup. An implant survival rate higher than 70% can be expected 25 years postoperatively. 相似文献