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11.
Background
The current status of radioiodine-131 (RaI) dosimetry for Graves' hyperthyroidism is not clear. Recurrent hyperthyroidism and iatrogenic hypothyroidism are two problems which interact such that trying to solve one leads to exacerbation of the other. Optimized RaI therapy has therefore begun to be defined just in terms of early hypothyroidism (ablative therapy) as physicians have given up on reducing hypothyroidism.Methods
Optimized therapy is evaluated both in terms of the greatest separation of cure rate from hypothyroidism rate (non-ablative therapy) or in terms of early hypothyroidism (ablative therapy) by mathematical modeling of outcome after radioiodine and critically discussing the three common methods of RaI dosing for Graves' disease.Results
Cure follows a logarithmic relationship to activity administered or absorbed dose, while hypothyroidism follows a linear relationship. The effect of including or omitting factors in the calculation of the administered I–131 activity such as the measured thyroid uptake and effective half-life of RaI or giving extra compensation for gland size is discussed.Conclusions
Very little benefit can be gained by employing complicated methods of RaI dose selection for non-ablative therapy since the standard activity model shows the best potential for cure and prolonged euthyroidism. For ablative therapy, a standard MBq/g dosing provides the best outcome in terms of cure and early hypothyroidism. 相似文献12.
自1994年以来,我院采用改良的尿道拖人术治疗外伤性后尿道狭窄22例,取得满意疗效,现报道如下。l临床资料本组病例均为男性,为严重车祸伤或高处跌伤致骨盆骨折所致,年龄则一46岁,平均35岁。临床症状有尿道四溢血、尿摊留、腹胀、肛周青紫肿胀,有休克者2例,合并直肠损伤2例,磅眈破裂6例。术中发现前列腺尖游离者4例。所有病例不能将导尿管插入膀跳,而均行单纯“耻骨上膀胜造疾术”,有膀脱破裂者行“膀脱破裂修补术”,有直肠损伤者,行“乙状结肠造疫术”。患者于术后3-6个月来院行尿道重建术。术前常规尿道造影,显示膜部尿道狭… 相似文献
13.
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
14.
Aldo Elmer Rafael Suresh Keshavamurthy Edgardo Sepulveda Cyndee Cruz Miranda Toshihiro Okamoto Gosta Bengt Pettersson 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2014,41(3):324-326
Cutaneous fistula as a clinical presentation of intracardiac abscess of the right side is such an unusual occurrence that it has not until now been reported in the English-language medical literature. We present a rare case of right-sided infective endocarditis caused by Achromobacter xylosoxidans in which recurrent infection presented as sternal wound discharge. The infection was found to have an intracardiac origin and was successfully managed by radical débridement on cardiopulmonary bypass. 相似文献
15.
M. Martin Jimenez A. Calvo Ferrandiz J. Aparicio Urtasun R. Garcia-Campelo E. Gonzalez-Flores M. Lazaro Quintela M. Muñoz Mateu C. A. Rodriguez Sanchez A. Santaballa Bertran J. M. Sepulveda Sanchez R. Vera Garcia J. A. Virizuela Echaburu M. A. Segui Palmer 《Clinical & translational oncology》2017,19(3):291-300
The coming into force of Directive 2001/20/EC represented a step forward in harmonising clinical trial regulation in European countries, guaranteeing a uniform protection of subjects participating in clinical research across Europe. However, it led to a disproportionate increase in the bureaucratization, and thus, it became evident that procedures needed to be simplified without detriment to patient’s safety. Thus, Regulation 536/2014, that repealed Directive 2001/20/EC, with the aim of decreasing the growing bureaucratization and stimulating clinical research in Europe, established simplified procedures, such as regulating a common procedure for authorising trials in Europe, the institution of strict assessment timelines, or the definition of new concepts, such as “low-intervention clinical trial”. The legal form of a Regulation allowed the norm to be directly applied to Member States without the need for transposition. By means of the new Royal Decree, the national legislation is adapted to make the application of the regulation feasible and it allows the development of the aspects that the Regulation leaves to national legislation. Both documents seek to stimulate clinical research with medicinal products to foster knowledge, facilitate transparency, and reinforce subjects’ safety. This will surely be the case, but with this revision, we will look at the novelties and key aspects that are most relevant to investigators and we will analyse the consequences for all parties involved in clinical research. 相似文献
16.
17.
Enhancement of chemotactic factor-stimulated neutrophil oxidative metabolism by leukotriene B4 总被引:4,自引:0,他引:4
Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci. 相似文献
18.
Shimada Y; Migliaccio G; Ralph H; Migliaccio AR; Shaw H$corrected to Ralph H 《Blood》1993,81(4):935-941
Recently, a variety of growth factor-dependent subclones of the murine interleukin-3 (IL-3)-dependent cell line 32D have been isolated. These subclones include those dependent for growth on erythropoietin (Epo) (32D Epo), granulocyte-macrophage colony-stimulating factor (GM-CSF) (32D GM), or granulocyte colony-stimulating factor (G-CSF) (32D G). 32D Epo1.1 is a revertant of 32D Epo and is capable of growing in IL-3. These cell lines express the differentiation program appropriate to the specific growth factor and depend on the growth factors not only for proliferation but also for survival. To determine how the signal for proliferation is triggered by various growth factors, we examined the DNA histograms and the expression of cell cycle-specific genes in the different cell lines. The cell cycle-specific genes analyzed were myc (early G1), myb (late G1), and the structural genes for the calcium- binding protein 2A9 (middle G1) and histone H3 (G1-S boundary). The DNA histogram analysis of cells in the logarithmic phase of growth showed that approximately 40% of 32D, 32D GM, 32D G, and 32D Epo1.1 (growing in IL-3) were cells with a 2N DNA content (and therefore in G0/G1), and another 40% have a DNA content intermediate between 2N and 4N (in S phase). In contrast, 32D Epo and 32D Epo1.1 (growing in Epo) had fewer cells in the G0/G1 phase of the cell cycle compared with the number of cells that were in the S phase (19% to 31% v 69% to 78%, respectively). Because all the cell lines have comparable doubling times (15 to 18 hours), the cell distribution among the phases of the cell cycle is proportional to the length of the phase. Therefore, cells growing in IL- 3 (32D and 32D Epo1.1), GM-CSF (32D GM), or G-CSF (32D G) progress along the cycle in a manner typical of previously reported nontransformed cell lines. In contrast, cells growing in Epo (32D Epo or 32D Epo1.1) spend relatively less time in G0/G1 and correspondingly more time in S. These data were confirmed by the analysis of the tritiated thymidine (3H-TdR) suicide rate and of the expression of cell cycle-specific genes. The 32D and 32D Epo1.1 cells growing in IL-3 had a suicide rate of congruent to 50%, whereas the suicide rate of 32D Epo and 32D Epo1.1 growing in Epo was higher than 75%.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
19.
Histological patterns of gastritis in H. pylori-infected individuals with a family history of gastric cancer 总被引:9,自引:0,他引:9
Sepulveda A Peterson LE Shelton J Gutierrez O Graham DY 《The American journal of gastroenterology》2002,97(6):1365-1370
OBJECTIVE: Different types of chronic gastritis, including antral predominant, corpus predominant, and multifocal pangastritis, are associated with Helicobacter pylori infection. Specific patterns of H. pylori gastritis that might characterize individuals with family histories of noncardia gastric cancer (GC) were investigated. METHODS: Histopathological changes associated with H. pylori gastritis were assessed in 111 individuals with family histories of GC and in 77 without from a region with high prevalence of H. pylori infection and GC. Gastric biopsies were taken from 12 sites (antrum, five; corpus, six; and cardia, one). RESULTS: Individuals (age < 36 yr) with family histories of GC developed pangastritis and had higher H. pylori bacterial scores (p < 0.05) in the gastric corpus, whereas those without family histories of GC typically had antral predominant gastritis. The correlation between density of polymorphonuclear leukocytes and density of H. pylori at each biopsy site was statistically significant (p < 0.01). Pangastritis was associated with a higher density of lymphoid aggregates and follicles (p < 0.05) in the corpus of younger individuals (age < 36) and in the antrum of older individuals (age > or = 48) with positive family histories of GC. CONCLUSIONS: Pangastritis and high lymphoid follicle density associated with H. pylori infection were found in patients with family histories of GC. Because a family history of gastric carcinoma is associated with increased risk of gastric cancer development, characterization of histological patterns of gastritis may be applicable to gastric cancer screening and surveillance, especially in relatively young at-risk populations. 相似文献
20.
Hyperbaric oxygen therapy improves angiogenesis and bone formation in critical sized diaphyseal defects
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JP Grassmann J Schneppendahl AR Hakimi M Herten M Betsch TT Lögters S Thelen M Sager M Wild J Windolf P Jungbluth M Hakimi 《Journal of orthopaedic research》2015,33(4):513-520
Besides the use of autologous bone grafting several osteoconductive and osteoinductive methods have been reported to improve bone healing. However, persistent non‐union occurs in a considerable number of cases and compromised angiogenesis is suspected to impede bone regeneration. Hyperbaric oxygen therapy (HBO) improves angiogenesis. This study evaluates the effects of HBO on bone defects treated with autologous bone grafting in a bone defect model in rabbits. Twenty‐four New‐Zealand White Rabbits were subjected to a unilateral critical sized diaphyseal radius bone defect and treated with autologous cancellous bone transplantation. The study groups were exposed to an additional HBO treatment regimen. Bone regeneration was evaluated radiologically and histologically at 3 and 6 weeks, angiogenesis was assessed by immunohistochemistry at three and six weeks. The additional administration of HBO resulted in a significantly increased new bone formation and angiogenesis compared to the sole treatment with autologous bone grafting. These results were apparent after three and six weeks of treatment. The addition of HBO therapy to autologous bone grafts leads to significantly improved bone regeneration. The increase in angiogenesis observed could play a crucial role for the results observed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:513–520, 2015. 相似文献