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101.
We have analyzed the radiologic findings on the lumbar spine and the clinical symptoms in patients with rheumatoid arthritis (RA). A total of 106 patients who fulfilled the revised criteria of the American Rheumatism Association were subjected. All of the patients were asked to fill out a questionnaire about the existence of low back pain, leg pain, and leg numbness. Radiologic features of the lumbar spine, including scoliosis, spondylolisthesis, disc space narrowing, endplate erosion, osteophyte, and osteoporosis, were checked. Radiographs of the cervical spine were also taken. The clinical background of RA, such as mutilating disease or not, was assessed. Forty-two patients (40%) had the symptoms of low back pain. Abnormal radiologic findings in lumbar spine were detected in 57%. The prevalence of clinical symptoms tended to be higher in the patients with endplate erosion. Forty-two percent of the patients had both lumbar and cervical lesions. The prevalence of lumbar lesion was not high in the mutilating type of RA, except for facet erosion and severe osteoporosis. The patients with pulse steroid therapy revealed a higher prevalence of vertebral fracture. From these results, we concluded that lumbar lesions were frequently observed in patients with RA. The possibility of lumbar lesions as well as the lesions in the cervical spine and peripheral joints should be examined in patients with RA.  相似文献   
102.
103.
We report a 49-year-old female patient with secondary myelodysplastic syndrome who developed liver dysfunction and acute renal failure caused by low-dose cytosine arabinoside (Ara-C) therapy. Treatment of low-dose Ara-C has widely been used for acute myelogeous leukemia and myelodysplastic syndrome, and it is thought to be a low toxicity except for myelosuppression. The patient complained of a transient adverse reaction in the second and third course of therapy. This rare case indicates that careful observation should be carried out during low-dose Ara-C therapy in view of allergic reactions.  相似文献   
104.
We report the characteristics of magnetic resonance imaging (MRI) of cystic intradural extramedullary spinal cord tumors (cystic neurilemmoma, epidermoid cyst, and enterogeneous cyst). T1-weighted MRI enhanced with gadolinium-DTPA clearly demonstrated the rim morphology of these tumors. The comparison between the rim enhancement pattern and histopathological findings offered possible qualitative diagnosis of these cystic spinal cord tumors by MRI.  相似文献   
105.
106.
Lymph node metastasis is a major prognostic factor for esophageal squamous cell carcinoma (ESCC). In recent years, endoscopic mucosal resection (EMR) has been developed with excellent results for the treatment of the superficial ESCC. To make the EMR treatment successful, it is important to establish a good indicator to identify ESCC patients at a high risk of lymph node metastasis. In this study, we examined clinicopathological and immunohistochemical factors to investigate the factors involved in lymph node metastasis of ESCC invading to the submucosal layer (sm-ESCC). Surgical specimens from 84 sm-ESCC patients were examined. Among 84 sm-ESCC patients, 33 (39.3%) had lymph node metastases. Clinicopathologically, tumor depth, lymphatic invasion and blood vessel invasion showed significant correlations with lymph node metastasis by univariate analysis. Tumor depth and lymphatic invasion showed significant correlations by multivariate analysis of these factors. Immunohistochemically, P53 accumulation was observed in 45 cases (53.6%), cyclin D1 overexpression in 25 (29.8%), and pRB in 65 (77.4%). P53 accumulation, cyclin D1 overexpression and MIB-1 Labeling Index were significantly associated with lymph node metastasis by univariate analysis, and P53 accumulation showed a significant correlation with lymph node metastasis by multivariate analysis. Among tumor depth, lymphatic invasion and P53 accumulation, tumor depth and lymphatic invasion were significantly correlated with lymph node metastasis ( P =0.0023 and P =0.0092, respectively) by multivariate analysis. These data suggest that tumor depth and lymphatic invasion can be considered as good indicators for lymph node metastasis among patients with sm-ESCC. In addition, P53 accumulation could be helpful to identify the patients who need additional treatment after EMR.  相似文献   
107.
Segmental hair analysis is used to estimate the time of drug intake at monthly precision in drug‐related crimes. Previously, we advanced this analytical method to specify the day of drug intake by cutting a strand of hair into 0.4‐mm segments, which correspond to daily hair growth. Herein, we investigated the distributions of 7 compounds in a strand of hair using micro‐segmental analysis. Several strands of hair were collected 33.1?229.4 days after subjects were administered 4 pharmaceutical products that contained 10 drugs in single doses within 32 hours. The administered drugs and resulting metabolites were extracted from 0.4‐mm hair segments and quantified using liquid chromatography–tandem mass spectrometry. Acidic and neutral compounds were detected at low amounts in any of the hair segments analyzed. Epinastine, fexofenadine, dihydrocodeine, chlorpheniramine, and the chlorpheniramine metabolite, desmethylchlorpheniramine each was localized to 2 regions within a strand of hair. By contrast, methylephedrine and its metabolite, ephedrine, each was localized to only a region. Among 20 individual strands of hair associated with different subjects and head regions, few differences in the shapes of drug concentration–hair segment curves for each compound were detected. Our data indicated that 2 mechanisms for drug uptake into hair can operate depending on drug properties and that co‐administered drugs can be localized to different regions in a strand of hair. Micro‐segmental analysis may aid in the identification of the day of drug intake and help to elucidate the mechanisms of drug uptake into hair.  相似文献   
108.
Background: Well‐known risk factors for Clostridium difficile infection (CDI) are exposure to antibiotics and gastric acid suppressants. Recent studies have provided some evidence of an association between hypovitaminosis D and the risk of CDI. Therefore, this meta‐analysis aimed to pool all the existing evidence to investigate the association between 25‐hydroxyvitamin D (25[OH]D) and CDI. Methods: A systematic search was conducted in 3 databases (PubMed, Embase, and Web of Sciences) for epidemiological studies that examined the association between mean 25(OH)D concentrations and CDI as well as between 25(OH)D status and CDI severity or recurrence. 25(OH)D status was defined as “lower” or “higher” at a threshold concentration of <20 or ≥20 ng/mL, respectively. Pooled effect sizes were computed using the inverse variance heterogeneity model of meta‐analysis. Results: Eight publications (n = 4479 patients) were included in the meta‐analysis. The mean concentration of 25(OH)D in patients with CDI was 3.54 ng/mL (95% confidence interval [CI], 0.39–6.89 ng/mL) lower than in patients without CDI. Patients with lower 25(OH)D status had a higher odds (odds ratio [OR], 1.61; 95% CI, 1.02–2.53) of developing severe CDI compared with those with a higher 25(OH)D status. No significant association was found between 25(OH)D status and CDI recurrence. Conclusion: The results of this meta‐analysis suggest that lower mean concentrations of 25(OH)D were associated with CDI. A lower 25(OH)D status increased the odds of severe CDI but not of CDI recurrence.  相似文献   
109.
To overcome a number of challenges involved in analyzing methcathinone (MC) analogues, we performed gas chromatography‐mass spectrometry (GC‐MS) analysis, including sample preparation, of nine MC analogues ? 4‐methylmethcathinone, three positional isomers of fluoromethcathinones, 4‐methoxymethcathinone, N‐ethylcathinone, N,N‐dimethylcathinone, buphedrone, and pentedrone. The MC analogues underwent dehydrogenation when the free bases were analyzed using splitless injection. Most of this thermal degradation was prevented using split injection. This indicated that a shorter residence time in the hot injector prevented decomposition. Uniquely, 2‐fluoromethcathinone degraded to another product in a process that could not be prevented by the split injection. Replacing the liner with a new, clean one was also effective in preventing thermal degradation. Most of the analytes showed a substantial loss (>30%) when the free base solution in ethyl acetate was evaporated under a nitrogen stream. Adding a small amount of dimethylformamide as a solvent keeper had a noticeable effect, but it did not completely prevent the loss. Three positional isomers of fluoromethcathinones were separated with baseline resolution by heptafluorobutyrylation with a slow column heating rate (8 °C/min) using a non‐polar DB‐5 ms capillary column. These results will be useful for the forensic analysis of MC analogues in confiscated materials. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
110.
In forensic drug testing, it is important to immediately take biological specimens from suspects and victims to prove their drug intake. We evaluated the effectiveness of saliva and fingerprints as alternative specimens to urine and blood in terms of ease of sampling, drug detection sensitivity, and drug detection periods for each specimen type. After four commercially available pharmaceutical products were administered to healthy subjects, each in a single dose, their urine, blood, saliva, and fingerprints were taken at predetermined sampling times over approximately four weeks. Fourteen analytes (the administered drugs and their main metabolites) were extracted from each specimen using simple pretreatments, such as dilution and deproteinization, and were analyzed using liquid chromatography/mass spectrometry (LC/MS). Most of the analytes were detected in saliva and fingerprints, as well as in urine and blood. The time‐courses of drug concentrations were similar between urine and fingerprints, and between blood and saliva. Compared to the other compounds, the acidic compounds, for example ibuprofen, acetylsalicylic acid, were more difficult to detect in all specimens. Acetaminophen, dihydrocodeine, and methylephedrine were detected in fingerprints at later sampling times than in urine. However, a relationship between the drug structures and their detection periods in each specimen was not found. Saliva and fingerprints could be easily sampled on site without using special techniques or facilities. In addition, fingerprints could be immediately analyzed after simple and rapid treatment. In cases where it would be difficult to immediately obtain urine and blood, saliva and fingerprints could be effective alternative specimens for drug testing. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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