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The intrauterine contraceptive device is used extensively in the female population. Serious complications are rare, but they do occur. We discuss three cases of bowel perforation caused by these devices following their perforation through the uterine wall. It is important that cases of perforation be recognised swiftly and the possibility of involvement of other organs considered.  相似文献   
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PURPOSE: The primary purpose of this study was to determine whether mutations of the class I beta-tubulin gene may be implicated in the inherent resistance to tubulin-binding agents (TBA) in renal cancer, with a small number of samples and cell lines also being examined for class I and III beta-tubulin isotype protein expression. EXPERIMENTAL DESIGN: DNA was extracted from 90 renal tumors and the class I beta-tubulin gene analyzed for mutations. For each sample, eight PCRs were used to cover the complete coding sequence with intronic primers ensuring highly homologous pseudogenes were not coamplified. Additionally, expression levels of class I and III beta-tubulin isotypes in 17 matched normal and malignant renal samples and a panel of renal cell carcinoma cell lines with differing intrinsic resistance to the TBAs was examined by Western blotting. RESULTS: Four polymorphic sequence changes of the class I beta-tubulin gene were identified with no mutations. Class I protein expression levels were higher in tumor tissue versus normal tissue, whereas class III expression showed no consistent change. In renal cancer cell lines, a significant correlation between class III isotype expression and vinblastine sensitivity was observed. CONCLUSIONS: These results do not support a role for mutations in the class I beta-tubulin gene in the intrinsic resistance of renal cancer to TBAs. Class III isotype expression may be implicated in resistance in vitro but in vivo, changes in class I isotype expression in renal cell carcinoma tissue may support a role in resistance to the TBAs and warrants further investigation.  相似文献   
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Serum beta2-microglobulin, the light chain of the HLA class I molecular complex, remains one of the best survival prognostic factors in multiple myeloma, but other HLA class I molecules might be of interest in monoclonal gammopathies. In this study, we evaluate total soluble HLA class I (HLA-Is) and soluble HLA-G (HLA-Gs) in 103 patients with newly diagnosed multiple myeloma, 30 patients with monoclonal gammopathy of undetermined significance (MGUS), and 30 healthy subjects, studying their prognostic value in multiple myeloma. In multiple myeloma patients, HLA-Is and HLA-Gs median values were 0.8 microg/mL and 28 ng/mL, respectively. Median HLA-Is concentration was higher in stage II and III multiple myeloma patients than in stage I multiple myeloma, MGUS, and control patients. Median HLA-Gs was significantly lower in healthy controls than in MGUS and multiple myeloma patients. A high level of HLA-Is (> or =2.1 microg/mL) was predictive of short survival (P = 0.017). For each given level of beta2-microglobulin, the relative risk of death was higher for patients with HLA-Is > or = 2.1 microg/mL than in patients with a lower level (P = 0.047). HLA-Gs, a marker of monoclonal gammopathy, was of no prognostic value, but the addition of HLA-Is to beta2-microglobulin produced an efficient prognostic score (P < 0.0001). HLA-Is is a new marker of multiple myeloma tumor load and provides additional survival prognostic information to beta2-microglobulin.  相似文献   
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The small intestine is the major site of drug absorption. Some reports in the literature have evoked the concept of “absorption windows” in the small intestine: are there specific regions where drug absorption is significantly higher than others? To investigate this question, we used an everted gut sac method to study the permeability of drugs and markers every 3–4 cm down the entire small intestine in rat. These markers were chosen to be representative of the mechanisms by which drugs cross the small intestinal mucosa: paracellular and transcellular passive diffusion, via influx transporters, and a drug (digoxin) that is effluxed from cells by P-glycoprotein (P-gp). The passive diffusion and influx transporter markers gave similar profiles with a plateau of permeability along the jejunum, and with the exception of L-Dopa, lower permeability in the ileum. Digoxin showed a linear decrease in the profile from the proximal jejunum to the ileum. Permeability in the duodenum was two to three times lower than the jejunum for all compounds. There were no narrow specific regions of high permeability and so the concept of discrete “absorption windows” along the small intestine as suggested from some pharmacokinetic studies may be related to other effects such as pH and/or solubility.  相似文献   
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Recent reports have described neurobehavioral impairments in human subjects carrying a V66M polymorphism in the gene encoding brain-derived neurotrophic factor (BDNF). Inasmuch as ventral nervous system (CNS) deficits associated with this BDNF polymorphism are similar to those observed among subjects with chronic exposure to elemental mercury (Hg degrees ), we examined the potential effect of this BDNF polymorphism on symptoms and mood in an established cohort of dental practitioners with chronic low-level Hg degrees exposure. Self-reported symptoms and mood were obtained by computerized questionnaire from 193 male dentists (DTs) and 230 female dental assistants (DAs). Spot urine samples were analyzed for mercury concentrations to evaluate recent exposure. Detailed work histories were obtained to calculate chronic indices of Hg degrees exposure. Buccal cell samples were obtained to identify the V66M polymorphism of BDNF. Scores for 11 current and 12 recent and chronic symptom groups, along with six mood factors, were evaluated with respect to recent and chronic Hg degrees exposure and BDNF polymorphism. Multiple regression analysis controlled for age, race, socioeconomic status, tobacco and alcohol use, self-reported health problems, and medications. Separate evaluations were conducted for DTs and DAs. Twenty-three associations between recent or chronic Hg degrees exposure and BDNF status and self-reported symptoms were observed with p < 0.10. All but three were in the expected direction (symptom scores increasing with Hg degrees exposure or BDNF polymorphism), and all but six were among DAs. All eight correlations between chronic exposure indices and recent and chronic symptoms among DAs were in the expected direction. All seven associations between BDNF and symptoms were in the expected direction and split between DTs and DAs. All three associations with mood factors were among DAs and in the expected direction. These results indicate that among DAs very low levels of occupational Hg degrees exposure are associated with increased symptoms. The BDNF polymorphism is also associated with increased symptom and mood scores. Notably, Hg degrees and BDNF polymorphism were additive with respect to their associations with the same symptom group.  相似文献   
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BackgroundMaintenance of patellar stability requires a balance between the vastus medialis oblique (VMO) and the vastus lateralis (VL). The imbalance between these muscles is thought to be implicated in the etiology of patellofemoral pain (PFP). Where there is hypertrophy of the VL in PFP patients, self-myofascial release (SMR) may be utilized for its management. However, there is no current evidence regarding SMR and its effects on VMO and VL architecture. The aim of this study, therefore, was to use ultrasound to gain further understanding of the effects of a program of SMR on the fiber angles of the VMO and VL.HypothesisThere will be a significant decrease in the pennation angles of the VMO and VL after seven weeks of SMR using a foam roller.Study DesignCohort StudyMethodsTwenty-five young, athletic, male participants were recruited to use a foam roller, along the full length of both anterior thighs, three times weekly, on three separate days, for seven weeks. Ultrasound was used to determine the initial and final VMO and VL pennation angles on both limbs. One eligible participant was chosen as an intra-rater control and did not partake in the SMR regimen.ResultsThere was a statistically significant (p < 0.001) decrease in the pennation angles of the VMO and VL after the SMR regime. Mean combined right and left VL angle change was -6.65° (-18% mean change) and the mean combined right and left VMO angle change was -7.65° (-11.5% mean change). A weak negative correlation was found between initial VMO fiber angle and the angle change (Rsquared = -0.21), as well as moderate negative correlation for the VL (Rsquared = -0.51).ConclusionA program of SMR on the anterior thighs of young, asymptomatic males resulted in changes to the fiber angles of both the VMO and VL. There was a significant decrease in pennation angle after seven weeks of SMR using a foam roller.  相似文献   
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