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1.
锂是人体内的一种微量元素且以化合物的形式广泛存在于自然界。作为一种古老的治疗精神疾病方面的药物,锂盐被用来治疗双相情感障碍已超过60年,而现在锂盐在临床上表现出来的新应用已经越来越引起医学界的广泛重视。现代研究表明,锂盐是一种强大的糖原合成酶激酶-3(GSK-3β)抑制剂,锂盐除对脑细胞过度活动起抑制作用外,还具有营养神经和保护神经、抗炎、抗氧化、抗癌、免疫调节以及对甲状腺功能亢进的治疗作用。锂盐化学结构相对简单,而且目前人们对锂盐的使用经验及对锂离子的血药浓度监测手段已日趋成熟,所以锂盐具有相当好的临床应用前景,未来更进一步加大对锂盐的临床应用及作用机制的研究力度。现就锂盐新发现的作用机制及临床应用作一综述。  相似文献   
2.
Fourier transform infrared (FTIR) spectroscopic imaging is an emerging microscopy modality for clinical histopathologic diagnoses as well as for biomedical research. Spectral data recorded in this modality are indicative of the underlying, spatially resolved biochemical composition but need computerized algorithms to digitally recognize and transform this information to a diagnostic tool to identify cancer or other physiologic conditions. Statistical pattern recognition forms the backbone of these recognition protocols and can be used for highly accurate results. Aided by biochemical correlations with normal and diseased states and the power of modern computer-aided pattern recognition, this approach is capable of combating many standing questions of traditional histology-based diagnosis models. For example, a simple diagnostic test can be developed to determine cell types in tissue. As a more advanced application, IR spectral data can be integrated with patient information to predict risk of cancer, providing a potential road to precision medicine and personalized care in cancer treatment. The IR imaging approach can be implemented to complement conventional diagnoses, as the samples remain unperturbed and are not destroyed. Despite high potential and utility of this approach, clinical implementation has not yet been achieved due to practical hurdles like speed of data acquisition and lack of optimized computational procedures for extracting clinically actionable information rapidly. The latter problem has been addressed by developing highly efficient ways to process IR imaging data but remains one that has considerable scope for progress. Here, we summarize the major issues and provide practical considerations in implementing a modified Bayesian classification protocol for digital molecular pathology. We hope to familiarize readers with analysis methods in IR imaging data and enable researchers to develop methods that can lead to the use of this promising technique for digital diagnosis of cancer.  相似文献   
3.
Vascularization is one of the key steps for engraftment in regenerative medicine. Previously one of the authors had discovered peptides exhibiting significant angiogenic activities designated AGP and elucidated the active core. For neovascularization basic fibroblast growth factor is used although permeation can be envisaged. The original AGPs did not suffer from this although their half-life times are short because of decomposition by endogenous enzymes. Several new AGP-libraries have been constructed and their enzymatic resistance has been investigated by the use of human umbilical vein endothelial cells to find candidates for clinical applications.  相似文献   
4.
Regression models for correlated categorical data are presented in which the covariance is a function of measured effects. The regression and covariance parameters are estimated by extended least square methods. A numerical example of a clinical trial comparing two antiemetic treatment regimes for patients receiving chemotherapy is given to illustrate the approach.  相似文献   
5.
We used advanced spectral imaging for intrasurgical decision making in a preclinical study, on a mouse model of Hirschsprung's Disease. Our imaging device sampled areas from normal and abnormal (aganglionic) colon in these animals. Spectral segmentation and classification of the resulting images showed a clear distinction between the normal and aganglionic regions, as confirmed by pathological analysis and use of mutant mice. We developed a simple algorithm that could distinguish normal from aganglionic colon with high spatial resolution and reproducibility, and the following statistics: sensitivity = 97%, specificity = 94%, positive predictive value = 92%, negative predictive value = 98%. These studies showed translational proof of concept that spectral imaging could be used during operations, in real time, to help surgeons precisely distinguish normal from abnormal tissue without requiring traditional biopsy. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
6.
Sequential medical trials involving paired data   总被引:2,自引:0,他引:2  
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7.
《Fungal biology》2020,124(2):83-90
Latterly, the upsurge in use of antifungal drugs has brought about the emergence of several drug-resistance strains, making it skeptical to continue relying on current therapeutic regime. In the necessity of resistance-free antifungal agent, flavonoids presented possibilities of replacing existing drugs, displaying antifungal activity against pathogenic fungi. Among them, quercetin, one of the most representative flavonoids, exhibited antifungal activity against Candida albicans. To inspect the further understanding regarding quercetin, the antifungal mode of action of quercetin was investigated. In the initial step, the apoptosis was monitored after quercetin treatment. Moreover, intracellular levels of Mg2+ was assessed and was determined that Mg2+ increase occurred under the influence of quercetin. In addition, several features of mitochondrial dysfunction were monitored. Mitochondrial dysfunction triggers decrease in mitochondrial redox levels and leads to disruption in mitochondrial antioxidant system. Increased intracellular ROS and decreased intracellular redox levels were also displayed, indicating the occurrence of overall disruption in antioxidant systems. Sequentially, DNA fragmentation was observed and this DNA damage in turn induces apoptosis. In analyses, hexaamminecobalt(III) chloride (Cohex) was applied to inhibit Mg2+ transport between cytosol and mitochondria. Cohex attenuated the effects induced by quercetin, which demonstrates that the presence of Mg2+ is essential in quercetin-induced apoptosis.  相似文献   
8.
D. L. Ribu, P. W. Shield and J. F. Bligh
The varied presentation of metastatic melanoma in fine needle aspiration cytology of the breast Objective: To identify cytomorphological patterns of metastatic melanoma (MM) in breast fine needle aspiration (FNA) specimens and highlight the differential diagnoses and features most useful in identifying MM. Methods: The clinical, radiological and FNA findings of 16 cases were reviewed. Cytological features evaluated related to cell arrangement, size and shape of cells, nuclear and cytoplasmic features, and the presence or absence of necrosis. Results: The series consisted of 14 females and two males, ranging in age from 24 to 83 years (mean = 50 years). A previous history of melanoma was available in 12/16 (75%) cases at the time of FNA reporting; however the clinical/radiological impression in 4/16 cases was of a breast cyst. The cases were classified into six morphological variants: classical (8/16), pseudopapillary (3/16), spindle‐cell (1/16), melanin‐rich (1/16), pleomorphic (2/16) and lymphoma‐like (1/16). The varying patterns raised a wide range of differential diagnoses; however, discohesion, binucleation and granular cytoplasm were the major features seen in 94% of all cases. In 14/16 cases (88%), plasmacytoid cells, prominent nucleoli and cytoplasmic vacuolation were identified. Melanin and multinucleation were detected in 44% of cases and intranuclear cytoplasmic invaginations in 63%. Necrosis was present in more than half of the cases (56%). Conclusion: MM should be considered in the differential diagnosis of breast FNA specimens when atypical cells are seen that present as plasmacytoid cells in a dispersed or pseudopapillary pattern, or as spindle, pleomorphic or pigmented cells. These features, combined with clinical history and immunocytochemistry, may assist in correctly identifying MM and directing optimal treatment.  相似文献   
9.
Metabolism is recognized as an important driver of cancer progression and other complex diseases, but global metabolite profiling remains a challenge. Protein expression profiling is often a poor proxy since existing pathway enrichment models provide an incomplete mapping between the proteome and metabolism. To overcome these gaps, we introduce multiomic metabolic enrichment network analysis (MOMENTA), an integrative multiomic data analysis framework for more accurately deducing metabolic pathway changes from proteomics data alone in a gene set analysis context by leveraging protein interaction networks to extend annotated metabolic models. We apply MOMENTA to proteomic data from diverse cancer cell lines and human tumors to demonstrate its utility at revealing variation in metabolic pathway activity across cancer types, which we verify using independent metabolomics measurements. The novel metabolic networks we uncover in breast cancer and other tumors are linked to clinical outcomes, underscoring the pathophysiological relevance of the findings.  相似文献   
10.
Methicillin-resistant Staphylococcus spp. (MRSS) are causing numerous forms of illness in humans ranging from mild to fatal infections. We need to investigate the resistant pattern for different clinical isolates to control the resistance phenomena. This study was designed to provide the resistance pattern of isolated Staphylococcus spp. from various clinical samples in Khartoum State and to elucidate the frequencies of Multidrug-resistant (MDR), Extensively drug-resistant (XDR) and pan-drug resistant (PDR). Two hundred and ten bacterial isolates were from different sources (catheter tip, sputum, vaginal swab, urine, tracheal aspirate, blood, pus, nasal swab, stool, throat swab, pleural fluid, and ear swab). Isolates were identified based on their morphological characters and biochemical reaction. Antibiotics susceptibility screening was performed using twenty-three antibiotics from eighteen classes against all isolated Staphylococcus spp. following the Clinical and Laboratory Standards Institute (CLSI) guideline. The result revealed that out of 63 Gram-positive isolated bacteria, 52 (82.5%) were Staphylococcus spp. with a high incidence of S. aureus 37(71.2%). Out of all Staphylococcus spp., 38 (73.1%) were Methicillin-resistant (MR). The prevalence of MDR was higher in S. aureus (89.2%) than in S. epidermidis (75%). All Staphylococcus spp. displayed resistance to ampicillin and penicillin, while all S. aureus were sensitive to daptomycin and fosfomycin. One isolate was XDR possible PDR, while no PDR was reported in all isolated bacteria. This study provided evidence for the antimicrobial-resistant (AMR) burden in Sudan and highlighted the need for a practical and functional stewardship program to reduce the unreasonable costs of antibiotics.  相似文献   
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