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81.
82.
Surgical excision followed by histopathological examination is the gold standard for melanoma screening. However, the color-based inspection of hematoxylin-and-eosin-stained biopsies does not provide a space-resolved quantification of the melanin content in melanocytic lesions. We propose a non-destructive photo-thermal imaging method capable of characterizing the microscopic distribution and absolute concentration of melanin pigments in excised melanoma biopsies. By exploiting the photo-thermal effect primed by melanin absorption of visible laser light we obtain label-free super-resolution far-infrared thermal images of tissue sections where melanin is spatially mapped at sub-diffraction 40-μm resolution. Based on the finite-element simulation of the full 3D heat transfer model, we are able to convert temperature maps into quantitative images of the melanin molar concentration on B16 murine melanoma biopsies, with 4·10-4 M concentration sensitivity. Being readily applicable to human melanoma biopsies in combination with hematoxylin-and-eosin staining, the proposed approach could complement traditional histopathology in the characterization of pigmented lesions ex-vivo.  相似文献   
83.
Studies have shown that as many as 1 in 10 adults with chronic kidney disease has a monogenic form of disease. However, genetic services in adult nephrology are limited. An adult Kidney Genetics Clinic was established within the nephrology division at a large urban academic medical center to increase access to genetic services and testing in adults with kidney disease. Between June 2019 and December 2021, a total of 363 patients were referred to the adult Kidney Genetics Clinic. Of those who completed genetic testing, a positive diagnostic finding was identified in 27.1%, a candidate diagnostic finding was identified in 6.7% of patients, and a nondiagnostic positive finding was identified in an additional 8.6% of patients, resulting in an overall yield of 42.4% for clinically relevant genetic findings in tested patients. A genetic diagnosis had implications for medical management, family member testing, and eligibility for clinical trials. With the utilization of telemedicine, genetic services reached a diverse geographic and patient population. Genetic education efforts were integral to the clinic's success, as they increased visibility and helped providers identify appropriate referrals. Ongoing access to genomic services will remain a fundamental component of patient care in adults with kidney disease.  相似文献   
84.
An isoelectric focusing technique for the separation of alkaline phosphatase isoenzymes on cellulose acetate membrane is described. Optimal conditions for isoelectric focusing were established by changing ampholine concentration and focusing conditions. Bone, liver, intestinal, and placental isoenzymes can be resolved into vacious sub-bands in a pH range of 4.1 to 5.2. These sub-bands were correlated with the findings of electrophoretic isoenzyme separation. The whole procedure proves very simple to perform and comparatively time saving (4 h). This procedure may help clarify the problems of ALP isoenzyme differention when electrophoretic patterns are unresolved.  相似文献   
85.
86.
Our aim was to establish the safety and efficacy of barbed suture for enterotomy closure after laparoscopic right colectomy with intracorporeal anastomosis. This study included 47 patients who underwent laparoscopic right hemicolectomy with intracorporeal mechanical anastomosis and barbed suture enterotomy closure (barbed suture closure—BSC) for adenocarcinoma (with the exception of T4 lesions and metastasis), compared with 47 matched patients who underwent laparoscopic right hemicolectomy with intracorporeal mechanical anastomosis and conventional suture enterotomy closure (conventional suture closure—CSC) during the same period. Controls were matched for stage, age, and gender via a statistically generated selection of all laparoscopic right hemicolectomies performed from January 2009 until December 2015. There was no difference between the two groups in terms of age, sex, BMI, ASA, co-morbidity, previous abdominal surgery, cancer site and cancer staging. In terms of operating time (median 120 min for BSC and 127.5 min for CSC), histopathological results, surgical site complications (2.1% for BSC and 8.5% for CSC), hospitalization (median 6 days for BSC and 5 days for CSC), readmission rate (0%), there were no differences between the groups (p > 0.05). No significant differences were noted between the two groups in terms of the postoperative course. Our results support that the use of knotless barbed sutures for enterotomy closure after laparoscopic right colectomy with intracorporeal mechanical anastomosis is safe and reproducible.  相似文献   
87.
Purpose It has been extensively documented that the cyclooxygenase inducible form and 15-lipoxygenase are implicated in colorectal carcinogenesis. Nonetheless, the role of other enzymes involved in the arachidonic acid metabolism, such as 5-lipoxygenase, in colorectal neoplasms has not been fully ascertained. This study was designed to evaluate 5-lipoxygenase expression in sporadic colorectal adenocarcinomas by using immunohistochemistry and to analyze its potential correlations with clinicopathologic parameters and with cyclooxygenase-2 expression. Methods Expression of 5-lipoxygenase and cyclooxygenase-2 were evaluated by immunohistochemistry in 50 surgically resected sporadic colorectal adenocarcinomas (28 male and 22 female patients age range, 47–88 (mean age, 69 ± 8) years). The chi-squared and Spearman correlation tests were used to analyze correlations with clinicopathologic characteristics and to evaluate any relationships between expression of the two enzymes. P values <0.05 were considered statistically significant. Results 5-Lipooxygenase and cyclooxygenase-2 immunostaining was found in the cytoplasm of neoplastic cells in 41 (82 percent) and in 43 cases (86 percent), respectively. Spearman correlation test demonstrated a positive correlation in the expression of the two enzymes. A statistically significant correlation also was observed between 5-lipoxygenase expression and tumor stage and lymph node metastasis, whereas no significant correlations emerged regarding cyclooxygenase-2 expression and clinicopathologic parameters. Conclusions Our study demonstrates that 5-lipoxygenase is expressed in colorectal adenocarcinomas in association with cyclooxygenase-2 expression. Moreover, an elevated expression of this enzyme seems to be significantly correlated with tumor aggressiveness. Further studies would clarify the need for target therapies inhibiting both metabolic pathways in such tumors. Supported by the grants from the University of Messina, Messina, Italy. Presented at the meeting of the Italian Society of Anatomic Pathology and Diagnostic Cytopathology (SIAPEC), Venice, Italy, October 4 to 5, 2006.  相似文献   
88.
When we move toward a novel environment we may learn it in different ways, i.e., by walking around or studying a map. Both types of learning seem to be very effective in daily life navigation and correspond to two different types of mental representation of space: route and survey representation. In the present study, we investigated the neural basis of route and survey perspectives during learning and retrieval of novel environments. The study was carried out over 5 days, during which participants learned two paths from a different perspective (i.e., route learning and survey learning). Then participants had to retrieve these paths using a survey or route perspective during fMRI scans, on the first and fifth day. We found that the left inferior temporal lobe and right angular gyrus (AG) were activated more during recall of paths learned in a survey perspective than in a route perspective. We also found a session by perspective interaction effect on neural activity in brain areas classically involved in navigation such as the parahippocampal place area (PPA) and the retrosplenial cortex (RSC). A set of frontal, parietal and temporal areas showed different patterns of activity according to the type of retrieval perspective. We tested the context-dependent connectivity of right PPA, RSC and AG, finding that these areas showed different patterns of connectivity in relation to the learning and recalling perspective. Our results shed more light on the segregation of neural circuits involved in the acquisition of a novel environment and navigational strategies.  相似文献   
89.
BACKGROUND: The antemortem diagnosis of Alzheimer disease (AD) requires time-consuming and costly procedures. Therefore, biochemical tests that can direct the physician rapidly to the correct diagnosis are highly desirable. Measurement of single biochemical markers in cerebrospinal fluid (CSF), such as total tau protein and beta-amyloid peptide42 (Abeta42), shows robust alterations that highly correlate with the clinical diagnosis of AD but generally lack sufficient diagnostic accuracy. OBJECTIVE: To study the combination of CSF phosphorylated tau protein (phospho-tau) and Abeta42 as biochemical markers for AD. METHODS: We combined CSF measurements of phospho-tau and Abeta42 in 100 consecutive patients who under-went diagnostic workup for dementia and in 31 healthy control subjects. RESULTS: We found that the calculated ratio of phospho-tau to Abeta42 was significantly increased in patients with AD and provided high diagnostic accuracy in distinguishing patients with AD from healthy control subjects (sensitivity, 86%; specificity, 97%), subjects with non-AD dementias (sensitivity, 80%; specificity, 73%), and subjects with other neurological disorders (sensitivity, 80%; specificity, 89%). CONCLUSION: The diagnostic usefulness of the CSF ratio of phospho-tau to Abeta42 is superior to either measure alone and can be recommended as an aid to evaluating individuals suspected of having dementia.  相似文献   
90.
The irreversible loss of the dopamine-mediated control of striatal function is considered the functional substrate of the motor symptoms of Parkinson's disease. This pathological event causes a complex rearrangement of neuronal activity which involves specific dopamine-regulated cellular functions and, secondarily, several other cellular properties and transmitter systems. In the present study, we applied recently developed cDNA microarray technology to investigate the genetic correlates of the alterations produced by 6-hydroxydopamine-induced dopamine denervation in the nucleus striatum. We found that chronic dopamine denervation caused the modulation of 50 different genes involved in several cellular functions. In particular, products of the genes modulated by this experimental manipulation are involved both in the intracellular transduction of dopamine signal and in the regulation of glutamate transmission in striatal neurons, providing some information on the possible neuronal events which lead to the reorganization of glutamate transmission in the striatum of parkinsonian rats.  相似文献   
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