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1.
PURPOSE: To classify the veins of Retzius demonstrated at computed tomography (CT) during arterial portography (CTAP) on the basis of anatomic location and to evaluate the relationship between the frequency of CT visualization and associated disease. MATERIALS AND METHODS: The authors reviewed axial CTAP scans from 130 patients. Patients were classified into one of two groups: patients with liver cirrhosis (group 1 [n = 81]) and patients without liver cirrhosis (group 2 [n = 49]). RESULTS: The pathways of the veins of Retzius were classified as follows: (a) The ileocolic vein drained into the inferior vena cava (IVC) or the right renal vein through the right gonadal vein (n = 61); (b) the pancreaticoduodenal vein drained into the IVC (n = 8); (c) the proximal branches of the superior mesenteric vein drained into the left gonadal vein (n = 6); and (d) the ileocolic vein drained directly into the IVC (n = 5). The veins of Retzius were demonstrated in 41 (51%) of the 81 patients in group 1 and 26 (53%) of the 49 patients in group 2. There was no statistically significant difference between the two groups. CONCLUSION: The veins of Retzius were demonstrated at CTAP in approximately 50% of patients with and 50% of patients without liver cirrhosis.  相似文献   

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The role of nitric oxide (NO) in glucose-induced insulin secretion was studied in pancreatic beta-cells, HIT-T15. A role for NO is suggested since glucose stimulated NO production in a concentration-dependent manner. NG-monomethyl-L-arginine, a potent inhibitor of nitric oxide synthase, significantly inhibited glucose-induced nitric oxide production as well as insulin release in HIT-T15. Furthermore, this inhibitory effect can be reversed by sodium nitroprusside (SNP), a well known NO donor. While SNP alone did not stimulate insulin release, it potentiated the secretory response of HIT-T15 cells to glucose by approximately two-fold. Potentiation by SNP appears to be mediated by NO, since (i) the potentiation was completely abolished by 10 microM hemoglobin, a scavenger of NO; and (ii) was not affected by rhodanese plus sodium thiosulphate. Neither hemoglobin alone nor the combination of rhodanese and sodium thiosulphate had any effect on glucose induced insulin release. These results are consistent with the hypothesis that glucose-induced formation of NO may potentiate the effect of glucose by a positive feedback mechanism.  相似文献   

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The authors developed a new three-dimensional reconstruction method called "See-Through View (STV)" using a spiral CT in evaluating of cerebral arteriovenous malformation (AVM). Spiral CT was performed in eight patients with AVM. STV was obtained by reconstructing with a voxel transmission projection using a double threshold method. In all eight patients, STV images enable us to depict the nidus of AVM from all angles by see-throughing skull bone, evaluating the relationship of the vascular lesions adjacent to other cerebrovascular or skeletal structures. In conclusion, STV will provide us further spatial recognition, and will be greatly helpful for surgical planning.  相似文献   

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BACKGROUND: The standards of the American Association of Blood Banks describe a minimum hemoglobin level of 12.5 g per dL for apheresis donors. Until 1995, the authors' institution accepted occasional platelet donors with a lower minimum hemoglobin (11.5 g/dL), if accompanied by medical director approval. STUDY DESIGN: All donation records from a 6-month period before 1995 were retrospectively reviewed to determine whether this lower hemoglobin cutoff adversely affected either the safety of the platelet donation process or donors' subsequent hemoglobin levels. RESULTS: Of 450 donations, 56 (12%, Group 1) were from donors with hemoglobin concentrations between 11.5 and 12.4 g per dL (2 donations from 1 man; 54 donations from 45 women). The remaining 394 donations (88%, Group 2) came from donors with hemoglobin concentrations > or = 12.5 g per dL (216 donations from 118 men; 178 donations from 119 women). The frequency of donor reactions was acceptable (Group 1, 11%; Group 2, 6%); 2 percent of donations by Group 1 donors and 1 percent by Group 2 donors were terminated because of these reactions. Of 46 donors in Group 1, 30 returned to donate platelets again at a later time; at least once, 23 (77%) had a hemoglobin > or = 12.5 g per dL. Ten donors in Group 1 returned for additional donations within 56 days; no meaningful decrease in hemoglobin levels occurred. A hemoglobin cutoff of 12.5 g per dL during the study period would have excluded 1 percent of platelet donations by men and 23 percent by women. CONCLUSION: The data demonstrate that the lower hemoglobin cutoff of 11.5 g per dL is a safe and relevant threshold for accepting female plateletpheresis donors and would allow more participation by women in blood donor programs.  相似文献   

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The steady-state pharmacokinetics in serum and urine of the enantiomers of citalopram and its metabolites, demethylcitalopram (DCT) and didemethylcitalopram (DDCT), were investigated after multiple doses of rac-citalopram for 21 consecutive days (40 mg per day) to healthy human subjects who were extensive metabolisers of sparteine and mephenytoin. Comparable pharmacokinetic variability was noted for (+)-(S)-, (-)-(R)- and rac-citalopram. Enantiomeric (S/R) serum concentration ratios for citalopram were always less than unity and were constant during the steady-state dosing interval. A modest, but statistically significant, stereoselectivity in the disposition of citalopram and its two main metabolites was observed. Serum levels of the (+)-(S)-enantiomers of citalopram, DCT, and DDCT throughout the steady-state dosing interval investigated were 37 +/- 6%, 42 +/- 3% and 32 +/- 3%, respectively, of their total racemic serum concentrations. The (+)-(S)-enantiomers of citalopram, DCT, and DDCT were eliminated faster than their antipodes. For (-)-(R)- and (+)-(S)-citalopram, respectively, the serum t1/2 averaged 47 +/- 11 and 35 +/- 4 h and AUCss averaged 4,193 +/- 1,118 h.nmol/l and 2,562 +/- 1,190 h.nmol/l. The observed enantiospecificities were apparently more related to clearance, rather than to distributional mechanisms.  相似文献   

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BACKGROUND: Although low arterial oxygen tension (Po2) has been claimed to occur in one to two thirds of patients with cirrhosis, hypoxaemia appears to be rare in clinical practice. AIMS: To assess the frequency of arterial hypoxaemia in cirrhosis in relation to clinical and haemodynamic characteristics. PATIENTS: One hundred and forty two patients with cirrhosis without significant hepatic encephalopathy (grades 0-I) (41 patients in Child class A, 57 in class B, and 44 in class C) and 21 patients with hepatic encephalopathy. RESULTS: Mean Po2 in kPa was 11.3 in Child class A, 10.8 in class B, 10.6 in class C, and 10.6 in patients with encephalopathy (p < 0.05). The fraction of patients with Po2 below the lower normal limit of 9.6 kPa was 10%, 28%, 25%, and 43%, respectively in class A, B, C, and in patients with encephalopathy (p < 0.05). Oxygen saturation (So2) in these groups was respectively: 96%, 96%, 96%, and 93% (NS). So2 was below the lower limit of 92% in 0%, 9%, 7%, and 24% (p < 0.05). In patients without hepatic encephalopathy, a multivariate regression analysis revealed that independent determinants of a low Po2 were a high arterial carbon dioxide tension, a low systemic vascular resistance, and a low indocyanine green clearance (p < 0.0001). CONCLUSION: The prevalence of arterial hypoxaemia in cirrhosis is about 22% in patients without encephalopathy, but it varies from 10-40% depending on the degree of hepatic dysfunction. Arterial hypoxaemia in patients with cirrhosis of differing severity seems lower than previously reported, and patients with severe arterial hypoxaemia are rare.  相似文献   

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We compared the expression of inhibin A, chromogranin, synaptophysin, S-100 protein, cytokeratins AE1/AE3, 7, and 20, and estrogen and progesterone receptors in testicular sex cord-stromal tumors: 11 Sertoli cell tumors, 3 Sertoli cell adenomas (nodules), 26 benign Leydig cell tumors, 7 malignant Leydig cell tumors (defined clinically by metastatic behavior), and a variety of germ cell tumors. Inhibin was the most sensitive marker, expressed in 91% of the Sertoli cell tumors and 100% of the Sertoli cell adenomas and Leydig cell tumors. The non-neoplastic Sertoli and Leydig cells invariably stained for inhibin. Conversely, no germ cell tumors were immunoreactive. One testicular tumor of the adrenogenital syndrome was immunoreactive. Neuroendocrine marker immunoreactivity was variable. Chromogranin was expressed in the non-neoplastic Sertoli and Leydig cells, 82% of the Sertoli cell tumors, 92% of the benign Leydig cell tumors, and 43% of the malignant Leydig cell tumors. Synaptophysin was expressed in the non-neoplastic Sertoli and Leydig cells, 45% of the Sertoll cell tumors, and 70% of the Leydig cell tumors, in approximately similar proportions between the benign and malignant Leydig cell tumors. S-100 protein was expressed in 64% of the Sertoli cell tumors, 8% of the benign Leydig cell tumors, and none of the malignant Leydig cell tumors. Cytokeratins AE1/AE3 were expressed in 64% of the Sertoli cell tumors and 42% of the Leydig cell tumors, with similar proportions in the benign and malignant cases. Estrogen and progesterone receptor expression were identified in 24 and 39% of benign and malignant Leydig cell tumors, respectively. We conclude that inhibin is a characteristic marker for Sertoli and Leydig cells and that it serves to differentiate testicular sex cord-stromal tumors from germ cell tumors.  相似文献   

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Recent cloning and expression studies have revealed that the opioid mu-, delta-, kappa- and orphan receptors are seven-transmembrane domain receptors whose actions are mediated through activation of guanine nucleotide binding protein (G-protein). The activation of G-proteins by the opioid receptor can be measured by assessing agonist stimulation of membrane binding of the non-hydrolyzable analog of guanosine triphosphate (GTP), guanosine-5'-O-(3-[35S] thio) triphosphate ([35S] GTP gamma S). Our recent data suggest that 1) the level of spinal mu-, delta-, kappa- and orphan-receptor agonist-stimulated [35S] GTP gamma S binding closely parallels that of receptor binding densities, 2) the neuroanatomical distribution of opioid agonist-stimulated [35S] GTP gamma S binding relates to receptor binding distribution, 3) newly isolated opioid peptides, endomorphin-1 and -2, can activate G-proteins by specific stimulation of mu-receptors and act as partial agonists with moderate catalytic efficacies, 4) mu-receptor densities could be rate-limiting steps in the G-protein activation by mu-agonists in the spinal cord region. In conclusion, opioid agonist-stimulated [35S] GTP gamma S binding can provide a functional method to localize receptors not only by their ability to bind ligands, but also according to their ability to activate an intracellular signal transducer.  相似文献   

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In the smelting of copper and copper/nickel concentrates, the role of silica flux is to aid in the removal of iron by forming a slag phase. Alternatively, the role of flux may be regarded as a means of controlling the formation of magnetite, which can severely hinder the operation of a furnace. To adequately control the magnetite level, the flux must react rapidly with all of the FeO within the bath. In the present study, a rapid method for silica flux evaluation that can be used directly in the smelter has been developed. Samples of flux are mixed with iron sulfide and magnetite and then smelted at a temperature of 1250 °C. Argon was swept over the reaction mixture and analyzed continuously for sulfur dioxide. The sulfur dioxide concentration with time was found to contain two peaks, the first one being independent of the flux content of the sample. A flux quality parameter has been defined as the height-to-time ratio of the second peak. The value of this parameter for pure silica is 5100 ppm/min. The effects of silica content, silica particle size, and silicate mineralogy were investigated. It was found that a limiting flux quality is achieved for particle sizes less than 0.1 mm in diameter and that fluxes containing feldspar are generally of a poorer quality. The relative importance of free silica and melting point was also studied using synthetic flux mixtures, with free silica displaying the strongest effect.  相似文献   

13.
OBJECTIVE: The degree to which patient education in the areas of diet, exercise, and stress management can improve symptoms of irritable bowel syndrome (IBS) through healthier lifestyle behaviors is unknown. The aim of this study was to determine the effects of outpatient education on the short and long term outcomes, and the association between health-promoting behaviors and symptoms. METHODS: Pender's Health Promotion Model provided the theoretical framework. The study had a prospective longitudinal design. A consecutive sample of 52 adult outpatients with IBS attended a structured class that taught health-promoting modifications of lifestyle. Participants completed the Health-Promoting Lifestyle Profile (HPLP) and selected items from a Bowel Disease Questionnaire (BDQ) before the class and 1 month and 6 months later. Spearman rank correlations were used to assess the association between HPLP and symptom scores. Wilcoxon rank sum tests compared changes in scores versus their baseline values. RESULTS: Response rates at 1 and 6 months were 75% and 83%, respectively. Results revealed significant 1- and 6 month-improvements in pain and Manning symptoms (p < 0.01) and in some HPLP scores (exercise at 1 month, p < 0.05; stress management at 6 months, p < 0.01). Significant associations were found between some, but not all, HPLP and symptom scores over time. CONCLUSION: A structured IBS educational class for patients with IBS improved symptoms and some health-promoting behaviors. However, relationships among specific behaviors and specific symptoms did not consistently correspond with this improvement.  相似文献   

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Aseptic loosening of implant components is a common and important complication of both cemented and uncemented prosthetic joint replacements. Wear particles derived from organic polymer and metal implant biomaterials are commonly found within macrophages and macrophage polykaryons in the fibrous membrane between loose implant components and the host bone undergoing resorption. In order to determine whether biomaterial particle-containing, foreign-body macrophages may contribute to periprosthetic bone resorption, we cultured murine monocytes that had phagocytosed particles of biomaterials commonly employed in bone implant surgery [polymethylmethacrylate (PMMA), ultra-high molecular weight polyethylene (PE), titanium and chromium-cobalt] on bone slices and glass coverslips with UMR 106 osteoblast-like stromal cells in the presence of 1,25-dihydroxy-vitamin D3. Under these conditions, all biomaterial particle-containing, foreign-body macrophages differentiated into osteoclastic cells, i.e. tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells capable of extensive lacunar bone resorption. This study shows that particle phagocytosis by macrophages does not abrogate the ability of these cells to undergo osteoclast differentiation. These findings emphasise the importance of the foreign-body macrophage response to biomaterial wear particles in the pathogenesis of aseptic loosening.  相似文献   

16.
Presents a program development evaluation (PDE) method designed to integrate theory testing with the development and evaluation of action programs. Organizational development and action research as antecedents of PDE are addressed, and the PDE method is discussed, including its theory, objectives, and strength and fidelity. Two examples are cited to illustrate how the PDE method enables the translation of practitioner ideas into theoretical terms and promotes project development. Limitations and virtues of the method, such as its complexity and expense, are addressed. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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A method is described for the determination of radioactivity (microCi or MBq) at an organ site within an object or patient. Using both anatomic image data (CT or MRI scans) and planar gamma camera images, activity at depth is determined using a matrix inversion method based on least squares. The result of the inversion analysis was the unknown set of n linear (uniform) activity densities representative of each organ within the phantom or patient. The problem was overdetermined since the number of unknown activity densities (microCi/cm) was much less than the number of analysis points (N) within the nuclear image. This method, defined as the CT assisted matrix inversion (CAMI) technique, was accurate to within 15% for a three "organ" plastic phantom, wherein the organs were right circular cylinders having activities of 74 to 508 microCi (or 2.74 MBq to 18.8 MBq). This accuracy included image quantitation effects, particularly assumptions concerning attenuation correction. The average absolute percent error of the estimated activity in four distinct radioactive volumes in the phantom was 9.8%. It was found that the background activity within the phantom was estimated to be too high if sampling regions near strong sources were used in the analysis (scatter effect). This was minimized by going at least 2 cm away from such sources. By applying the method to a monoclonal antibody clinical study, activities within the patient's major organs such as liver, spleen, and kidney could be estimated, even in cases where the organ could not be visualized. Here, the CAMI algorithm gave internally consistent results for the patient's left and right lung linear activity concentrations. The CAMI technique resolves the problem of tissue superimposition using depth information from 3-D CT and is applicable in cases where a number of organs overlap in the gamma camera image. Thus, the method should be generally useful to nuclear image quantitation and the estimation of absorbed radiation doses in patients. One particular application is the estimation of radiation doses in radioimmunotherapy (RIT).  相似文献   

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BACKGROUND: Hair follicle preservation for the purpose of delayed application would help us to transplant hair follicles more efficiently. METHODS: Isolated single hair follicles were preserved at 4 degrees C in four different solutions. Viability of preserved follicles was judged by organ culture and cell culture. In addition, a small number of hair follicles were transplanted into athymic mice. RESULTS. By cell culture, both dermal papilla and outer root sheath cells could be cultivated after 7 days of preservation. Hair follicles preserved for 48 hours showed a significant increase of hair shafts in organ culture. Those preserved for 7 days regrew well when transplanted into athymic mice. CONCLUSION: Preservation of hair follicles at 4 degrees C could be one option to prepare many follicular units at one time for transplantation.  相似文献   

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The need for frequent injections and monitoring, the possibility of multiple gestations, and the higher cost compared to clomiphene citrate, prevents many clinicians from using human menopausal gonadotrophin (HMG) for ovulation induction. A sequential medication regimen, in which HMG is taken after clomiphene, overcomes these problems. We retrospectively compared per cycle fecundity and birth rates in 119 cycles of clomiphene-HMG, 524 cycles of clomiphene alone, 57 cycles of HMG alone, and 79 cycles of concurrent HMG and clomiphene in patients receiving intra-uterine insemination (IUI), who were free of endometriosis or tubal disease. Per cycle fecundity for clomiphene-HMG was 22% [95% confidence interval (CI) 12-34%], double that of clomiphene alone (11%) (95% CI 8-14%) (P < 0.01), and equal to HMG alone (18%) (95% CI 7-29%) or HMG and clomiphene together (19%) (95% CI 10-28%). The multiple birth rate for clomiphene-HMG (7/21) equalled that for HMG alone (3/12) and HMG and clomiphene together (3/8). The average number of ampoules of HMG required [follicle stimulating hormone (FSH) 75 mIU, luteinizing hormone (LH) 75 mIU] was decreased by 65% from 24.5 +/- 1.0 for HMG or HMG and clomiphene together to 8.6 +/- 0.3 for clomiphene-HMG (P < 0.001). Per cycle fecundity was identical when one, two or three ampoules of HMG per day were administered after clomiphene. We conclude that ovulation induction with sequential clomiphene-HMG results in fecundity double that of clomiphene alone and equal to HMG alone or concurrent with clomiphene, thereby reducing the requirement for HMG.  相似文献   

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