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排序方式: 共有354条查询结果,搜索用时 15 毫秒
51.
Molecular characterization of a high A2 beta thalassemia by direct sequencing of single strand enriched amplified genomic DNA 总被引:2,自引:0,他引:2
Two families, one of Anglo-Saxon-Dutch descent, and the other, West Indian black, have an atypical beta thalassemia characterized by an unusually high level of Hb A2 in the heterozygous state. Restriction endonuclease mapping showed a deletion of about 1.35 kilobase (kb) in the 5' region of the beta globin gene. Direct sequencing of a specific region of genomic DNA amplified by a new modification of the polymerase chain reaction defined the deletion to be 1,393 base pairs (bp) and to be the same in both families. The deletion extends from 485 bp 5' to the mRNA CAP site to the middle of the second intervening sequence. This deletion, together with three others previously described that remove the 5' end of the beta gene but leave the delta gene intact, are all associated with unusually high levels of Hb A2 in the heterozygous state. 相似文献
52.
Headache in lacunar stroke 总被引:1,自引:0,他引:1
The presence of headache within a 72-h interval of stroke onset was investigated in a cohort of 145 lacunar infarcts. Fourteen (10%) experienced diffuse or bilateral headache. Hypertension was less frequent (43 vs 76%; 95% CI: 6 to 60%) and of shorter duration (2.4 vs 7.8 years; t = 2.29; p = 0.02) among patients with headache. Leukoaraiosis was less frequent (40% vs 71%; 95% CI: −57 to −7%) and severe (7 vs 24%; 95% CI: −33 to −2%) in patients with headache. Age, sex, stroke risk factors, type of lacunar stroke, mode of onset, stroke severity, ultrasound and other CT findings were similar in patients with and without headache. No differences in the sixth month neurological or functional outcome were detected between lacunar patients with and without headache. Headache in lacunar stroke cannot be predicted by the clinical characteristics of the stroke and is not due to coexisting cardiembolism, intra or extracranial disease. Hypertensive small-vessel disease is less common and severe in lacunar strokes with associated headache. 相似文献
53.
The relationship between urinary calcium, sodium, and potassium excretion and the role of potassium in treating idiopathic hypercalciuria 总被引:1,自引:0,他引:1
OBJECTIVES: 1) To evaluate the relationships between urinary sodium (UNa), potassium (UK), and calcium (UCa) excretion in the pediatric population; and 2) to determine the effect of increasing potassium intake in patients with idiopathic hypercalciuria and investigate whether this intervention can be offered as another mode of therapy in this patient population. DESIGN: Prospectively, we determined UNa, UK, UCa, and creatinine (Cr) concentrations in randomly collected urine samples from children on initial evaluation for urinary frequency, dysuria, hematuria, enuresis, or kidney stones to identify children with hypercalciuria. SETTING: The outpatient renal clinic of an academic hospital. PARTICIPANTS: Twenty-three black children (13 girls and 10 boys) and 77 white children (44 girls and 33 boys) 3.92 to 16.67 years of age. INTERVENTIONS: Eleven children with hypercalciuria were given potassium supplementation or placed on a high-potassium diet for at least 2 weeks. OUTCOME MEASURES: UNa to UK, UNa to Cr, UK to Cr, and UCa to Cr ratios were calculated from measured levels of urinary minerals. These were repeated in 11 hypercalciuric patients after 2 weeks of increased potassium intake. RESULTS: A total of 100 urine samples were analyzed. The UCa/Cr ratio in blacks 0.04 +/- 0.06 (mean +/- standard deviation) was significantly lower than in whites 0.16 +/- 0.12. There were 21 hypercalciuric white children versus only 1 black child. Linear regression analysis revealed a positive direct correlation between UNa/Cr and UCa/Cr in all 100 subjects and in whites alone but not in blacks. An inverse relationship existed between UK/Cr and UCa/Cr in all subjects and in whites and showed a strong trend in blacks. A marked direct relationship was found between UNa/K and UCa/Cr in all subjects (r = .43) as well as in whites (r = .59) and blacks (r = .49). One black child and 10 white hypercalciuric children were treated with "extra" K for at least 2 weeks. The UNa/K decreased from 4.73 +/- 2.28 to 1.98 +/- 1.09, and the UCa/Cr decreased from 0. 31 +/- 0.10 to 0.14 +/- 0.07, with resolution or improvement of the patients' symptoms. CONCLUSIONS: In our patient population with urinary symptoms, the UCa/Cr ratio in black children is lower and hypercalciuria less common than in white children. In both white and black populations, the UNa/K ratio had the strongest association with the UCa/Cr ratio, indicating an opposing role of UNa and UK on the UCa/Cr ratio. Increased potassium intake was found to be beneficial for hypercalciuric children by decreasing the UNa/K ratio and, consequently, the UCa/Cr ratio. 相似文献
54.
Solitary fibrous tumor of the thyroid: cytopathologic findings and differential diagnosis 总被引:2,自引:0,他引:2
Parwani AV Galindo R Steinberg DM Zeiger MA Westra WH Ali SZ 《Diagnostic cytopathology》2003,28(4):213-216
Solitary fibrous tumor (SFT) is an uncommon mesenchymal neoplasm that arises primarily from the pleura. Extrapleural occurrences are rare. To our knowledge, there is no published account of this entity in the thyroid in the cytopathology literature. We report the case of a 61-yr-old man who was evaluated at The Johns Hopkins Hospital for a slow-growing thyroid mass that was present for 2 yr despite thyroid hormone suppression. Thyroid-stimulating hormone (TSH) was within normal limits. The patient underwent ultrasound-guided fine-needle aspiration (FNA), which showed predominantly discohesive slender spindle-shaped cells and fragments of collagenized stromal tissue. After the FNA diagnosis of "thyroid neoplasm" was made, the patient underwent a near-total thyroidectomy, which revealed a SFT. Differential diagnosis of spindle cell lesions in thyroid is also presented. 相似文献
55.
Clinical and sensorimotor gating effects of ketamine in normals. 总被引:4,自引:0,他引:4
E J Duncan S H Madonick A Parwani B Angrist R Rajan S Chakravorty T R Efferen S Szilagyi M Stephanides P B Chappell S Gonzenbach G N Ko J P Rotrosen 《Neuropsychopharmacology》2001,25(1):72-83
The clinical similarities between PCP psychosis and schizophrenia have contributed importantly to the development of the glutamate hypothesis of schizophrenia. Sensory gating, as measured by prepulse inhibition of the acoustic startle reflex (PPI), is impaired in patients with schizophrenia. In animals, the noncompetitive NMDA antagonists PCP and ketamine disrupt PPI in a way that resembles the defect seen in schizophrenia. The purpose of this work is to investigate the modulation of sensory gating in humans by subanaesthetic doses of ketamine. 16 healthy male subjects received a 60-min infusion of ketamine (0.5 mg/kg) or normal saline on two separate days in a randomized double-blind crossover design. Clinical ratings and PPI were done during the infusion on both days. Ketamine produced robust clinical effects. Dissociative symptoms as measured by the CADSS increased from 0 +/- 0.0 to 29.3 +/- 14.3; negative symptoms (Affect Rating Scale) increased from 17.2 +/- 0.8 to 24.8 +/- 3.1; and total BPRS scores increased from 18.3 +/- 0.8 to 26.4 +/- 5.1. ANOVAs for these ratings were all significant at the p <.000 level, although BPRS increases were not in the range seen in decompensated schizophrenic patients. The amplitudes of the startle responses to pulse-alone stimuli were not significantly different on ketamine and placebo days. Ketamine did not cause disruption in PPI as expected. On the contrary, in the first block of the PPI session ketamine significantly enhanced PPI (ANOVA; F=6.15, p =.026). These results indicate that the clinical effects of ketamine are not coupled with schizophrenic-like disruption of PPI in normal controls. 相似文献
56.
57.
Prostate Tumor Growth Can Be Modulated by Dietarily Targeting the 15-Lipoxygenase-1 and Cyclooxygenase-2 Enzymes 下载免费PDF全文
Uddhav P Kelavkar Justin Hutzley Kevin McHugh Kenneth GD Allen Anil Parwani 《Neoplasia (New York, N.Y.)》2009,11(7):692-699
The main objectives of our study were to determine the bioavailability of omega-3 (ω-3) to the tumor, to understand its mechanisms, and to determine the feasibility of targeting the ω-6 polyunsaturated fatty acids (PUFAs) metabolizing 15-lipoxygenase-1 (15-LO-1) and cyclooxygenase-2 (COX-2) pathways. Nude mice injected subcutaneously with LAPC-4 prostate cancer cells were randomly divided into three different isocaloric (and same percent [%] of total fat) diet groups: high ω-6 linoleic acid (LA), high ω-3 stearidonic acid (SDA) PUFAs, and normal (control) diets. Tumor growth and apoptosis were examined as end points after administration of short-term (5 weeks) ω-3 and ω-6 fatty acid diets. Tumor tissue membranes were examined for growth, lipids, enzyme activities, apoptosis, and proliferation. Tumors from the LA diet-fed mice exhibited the most rapid growth compared with tumors from the control and SDA diet-fed mice. Moreover, a diet switch from LA to SDA caused a dramatic decrease in the growth of tumors in 5 weeks, whereas tumors grew more aggressively when mice were switched from an SDA to an LA diet. Evaluating tumor proliferation (Ki-67) and apoptosis (caspase-3) in mice fed the LA and SDA diets suggested increased percentage proliferation index from the ω-6 diet-fed mice compared with the tumors from the ω-3 SDA-fed mice. Further, increased apoptosis was observed in tumors from ω-3 SDA diet-fed mice versus tumors from ω-6 diet-fed mice. Levels of membrane phospholipids of red blood cells reflected dietary changes and correlated with the levels observed in tumors. Linoleic or arachidonic acid and metabolites (eicosanoid/prostaglandins) were analyzed for 15-LO-1 and COX-2 activities by high-performance liquid chromatography. We also examined the percent unsaturated or saturated fatty acids in the total phospholipids, PUFA ω-6/ω-3 ratios, and other major enzymes (elongase, Delta [Δ]-5-desaturase, and Δ-6-desaturase) of ω-6 catabolic pathways from the tumors. We observed a 2.7-fold increase in the ω-6/ω-3 ratio in tumors from LA diet-fed mice and a 4.2-fold decrease in the ratio in tumors from the SDA diet-fed mice. There was an increased Δ-6-desaturase and Δ-9 desaturase enzyme activities and reduced estimated Δ-5-desaturase activity in tumors from mice fed the SDA diet. Opposite effects were observed in tumors from mice fed the LA diet. Together, these observations provide mechanistic roles of ω-3 fatty acids in slowing prostate cancer growth by altering ω-6/ω-3 ratios through diet and by promoting apoptosis and inhibiting proliferation in tumors by directly competing with ω-6 fatty acids for 15-LO-1 and COX-2 activities. 相似文献
58.
Clinical Relevance of Left Atrial Strain to Predict Recurrence of Atrial Fibrillation after Catheter Ablation: A Meta‐Analysis 下载免费PDF全文
Xin‐Xin Ma M.D. Leif‐Hendrik Boldt M.D. Yue‐Li Zhang M.D. Ph.D. Meng‐Ruo Zhu M.D. Bing Hu M.D. Abdul Parwani M.D. Evgeny Belyavskiy M.D. Aravind K. Radha Krishnan M.D. Maximilian Krisper M.D. Clemens Köhncke M.D. Engin Osmanoglou M.D. Martin Kropf M.Sc. Philipp Lacour M.D. Florian Blaschke M.D. Frank Edelmann M.D. Carsten Tschöpe M.D. Wilhelm Haverkamp M.D. Elisabeth Pieske‐Kraigher M.D. Burkert Pieske M.D. Daniel A. Morris M.D. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(5):724-733
59.
Labial adhesions are usually seen in early childhood or in the postmenopausal years, but this clinical entity is rarely seen in the reproductive years. We report a case of labial adhesion with acute urinary retention secondary to Bartholin's abscess in a reproductive‐aged woman with normal menstrual periods. We emphasize the possible occurrence of labial adhesion following Bartholin's abscess in the reproductive years with normal estrogen levels. 相似文献
60.
Esther Abels Liron Pantanowitz Famke Aeffner Mark D Zarella Jeroen van der Laak Marilyn M Bui Venkata NP Vemuri Anil V Parwani Jeff Gibbs Emmanuel Agosto-Arroyo Andrew H Beck Cleopatra Kozlowski 《The Journal of pathology》2019,249(3):286-294
In this white paper, experts from the Digital Pathology Association (DPA) define terminology and concepts in the emerging field of computational pathology, with a focus on its application to histology images analyzed together with their associated patient data to extract information. This review offers a historical perspective and describes the potential clinical benefits from research and applications in this field, as well as significant obstacles to adoption. Best practices for implementing computational pathology workflows are presented. These include infrastructure considerations, acquisition of training data, quality assessments, as well as regulatory, ethical, and cyber-security concerns. Recommendations are provided for regulators, vendors, and computational pathology practitioners in order to facilitate progress in the field. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献