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301.
目的:描述胚胎种植前遗传诊断在1例携带Ⅰ型白细胞黏附缺陷病(LAD-1)携带者并完成健康妊娠夫妇中的应用。设计:病例报道。机构:大学医院生殖中心。患者:1例男女双方都是LAD-1携带者的夫妇,女方CD18基因的外显子4携带有G400A置换,男方的外显子5携带有C562T置换。干预:标准体外受精(IVF)后第3天行卵裂期活检和分裂球遗传分析以检测2处突变以及21号染色体标记物。主要观察指标:1个未罹患LAD-1婴儿的出生。结果:得到15个卵母细胞,其中10个受精。8个胚胎适宜胚胎活组织检查。  相似文献   
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303.
BACKGROUND: This study examines trends in the presentation and surgical management of acute diabetic foot problems in a single institution. METHOD: Prospective audit of all diabetic patients who had a primary procedure for critical lower limb ischaemia (CLI) and/or foot sepsis between 1st January 1990 and 31st December 2002. Primary and secondary intervention, mortality and limb salvage rate within 6 weeks of the index procedure were recorded. RESULTS: There were 661 patients (417 men and 244 women of median age 69, range 31-99, years) with 799 affected limbs. CLI alone was present in 625 (78%) limbs, combined CLI and foot sepsis in 53 (7%) and foot sepsis alone in 121 (15%). The primary intervention was minor amputation in 323 (40%) limbs, revascularisation in 288 (36%), major amputation in 185 (23%) and sympathectomy in three limbs. Within 6 weeks, 125 (16%) limbs required secondary intervention, the peri-procedural mortality rate was 38 of 924 (4%), and the limb salvage rates for patients with CLI, combined CLI and sepsis and sepsis alone were 66, 66 and 80%, respectively. There was a significant decline in the proportion of patients presenting with CLI alone and a significant increase in the proportion presenting with combined CLI and sepsis and sepsis alone. In patients with CLI alone, there was a significant increase in the primary major amputation rate and a significant decline in the minor amputation rate with no significant change in the revascularisation rate. CONCLUSION: There has been a progressive decline in the proportion of patients presenting with CLI alone and a greater proportion of patients presenting with an element of foot sepsis. In patients with CLI alone, the primary major amputation rate has increased at the expense of a decline in minor amputation rate.  相似文献   
304.
Effects of acute liver injury on blood coagulation   总被引:1,自引:0,他引:1  
Summary.  The mechanisms leading to the hemostatic changes of acute liver injury are poorly understood. To study these further we have assessed coagulation and immune changes in patients with acute paracetamol overdose and compared the results to patients with chronic cirrhosis and normal healthy controls. The results demonstrate that in paracetamol overdose coagulation factors (F)II, V, VII and X were reduced to a similar degree and were significantly lower than FIX and FXI (mean levels 0.28, 0.16, 0.13, 0.19, 0.51 and 0.72 IU mL−1, respectively). In cirrhosis, by contrast, FII, FV, FVII, FIX and FX were equally reduced whilst FXI was lower than the other factors (mean levels 0.64, 0.69, 0.62, 0.60, 0.66 and 0.40 IU mL−1, respectively). FVIII was raised in paracetamol overdose patients but normal in those with cirrhosis (mean levels 1.95 and 1.01 IU mL−1, respectively). Interleukin-6 and tumor necrosis factor-α levels were raised in both patient groups, but higher levels were found in paracetamol overdose, compared to cirrhosis. Thrombin-antithrombin and soluble tissue factor levels were higher in those with acute liver injury but normal in cirrhosis. Antithrombin levels were reduced in both acute liver injury and cirrhosis. From these data we put forward a novel mechanism for the coagulation changes in acute paracetamol induced liver injury. We propose that immune activation leads to tissue factor-initiated consumption of FII, FV, FVII and FX, but that levels of FIX and FXI are better preserved because antithrombin inhibits the thrombin induced positive feedback loop that activates these latter factors.  相似文献   
305.
Glutathione-S-transferase (GST) genes encode a family of detoxification enzymes that offer protection against endogenous and exogenous sources of reactive oxygen species (ROS). Germline variations in GST genes may alter the catalytic efficiency of GST isoenzymes leading to a potential increase in susceptibility to the genotoxic effects of ROS and electrophilic substances. A nested case-control study design was used to examine the association between the polymorphic GST genes and prostate cancer risk among Finnish male smokers of the ATBC Cancer Prevention Study. A case-case analysis was used to determine the association between these genetic polymorphisms and prostate cancer progression. Germline DNA was obtained from 206 prostate cancer cases and 194 controls frequency matched on age, intervention group and study clinic. Cases and controls were genotyped for three GST genes using MALDI-TOF mass spectrometry or multiplex polymerase chain reaction (PCR). Relative to the wild-type genotype, we observed a 36% reduction in prostate cancer risk associated with the GST-M1-null genotype (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.43, 0.95). Unlike GST-M1, GST-T1-null (OR 0.74, 95% CI 0.42, 1.33) and GST-P1*B (OR 1.10, 95% CI 0.72, 1.69) were not strongly associated with prostate cancer risk. We did not observe any significant associations between the selected polymorphic GST genes and tumour grade or stage. In conclusion, we did not observe a direct association between polymorphic GST-T1 or GST-P1 and prostate cancer risk. Our observation of a relatively strong inverse association between the GST-M1-null genotype and prostate cancer risk needs to be confirmed in larger association studies.  相似文献   
306.
We aimed to evaluate the potential of the cerebrospinal fluid (CSF) axonal damage biomarker NfH(SMI35) in the laboratory-supported differential diagnosis of parkinsonian syndromes. Patients with idiopathic Parkinson's disease (PD; n = 22), multiple-system atrophy (MSA; n = 21), progressive supranuclear palsy (PSP; n = 21), corticobasal degeneration (CBD; n = 6), and age-matched controls (n = 45) were included. CSF levels of NfH(SMI35) were measured using ELISA. Levels of CSF NfH(SMI35) were elevated in PSP compared to PD and controls (P < 0.05 each). They were also significantly higher in MSA than in PD and controls (P < 0.05 each). NfH(SMI35) differentiated PD from PSP with a sensitivity of 76.5% and a specificity of 94.4%. Axonal damage as measured by CSF NfH(SMI35) is most prominent in the more rapidly progressive syndromes PSP and MSA as compared to PD or CBD. CSF NfH(SMI35) may therefore be of some value for the laboratory-supported differential diagnosis of atypical parkinsonian syndromes.  相似文献   
307.
Medullary thyroid carcinoma (MTC) is a rare form of thyroid cancer representing about 10% of all thyroid malignancies. It occurs mostly as a sporadic tumor or in association with autosomal dominant inherited cancer syndromes--multiple endocrine neoplasia (MEN) types 2A and 2B and familial MTC. Germline mutations in exons 8, 10, 11, 13, 14, 15 and 16 of the RET proto-oncogene are found in most of the familial cases. There are only a few published data reporting multiple germline mutations in the RET proto-oncogene. We have detected double germline mutations in 2 different exons on the same RET allele in two MEN 2 families. In the MEN 2A family, double germline mutation in exons 10 (Cys620Phe) and 13 (Tyr791Phe) was detected. In the MEN 2B family, beside the classical germline mutation in exon 16 (Met918Thr) a second germline mutation in exon 13 (Tyr791Phe) was found. This study revealed that MEN 2 syndromes can also be caused by double germline mutations in the RET proto-oncogene and these families can be added to small worldwide cohort of families with multiple germline mutations.  相似文献   
308.
The New Zealand obese mouse (NZO/Hl) is characterised by hereditary obesity and type-2 diabetes, including insulin resistance, hyperinsulinaemia, and glucose intolerance. In other diabetic models, it has been revealed that the proper functioning of the glucose transporter isoform 2 (GLUT2) is essential for adequate secretion of insulin. The aim of this study was to compare the distribution of islet cells and GLUT2, as well as the expression of GLUT2-mRNA, in the pancreas of NZO mice and metabolically unimpaired NMRI (Naval Medical Research Institute) mice. Pancreas tissue was obtained from different stages of development. For molecular determination of the expression level of GLUT2-mRNA, total-RNA was extracted from the pancreas and analysed by quantitative real-time RT-PCR. All investigated NZO mice displayed increased weight, elevated hyperinsulinaemia, and slightly enhanced blood glucose levels compared with the NMRI control mice. By means of immunofluorescence microscopy drastically reduced insulin levels were detected, which might be compensated by the observed islet cell hyperplasia and hypertrophy. Furthermore, the normally peripheral localisation of the alpha-cells within islets was disturbed. By contrast, there were no changes in somatostatin cell distribution. However, considerable differences appeared with regard to GLUT2: whereas the beta-cells of NMRI mice showed dense immunostaining of the GLUT2 transporter on the cell surface, in all age groups of NZO mice, GLUT2 on the plasma membranes was reduced and dispersed in the cytoplasm. These findings agree with the molecular biological results, which displayed decreased mRNA-expression of GLUT2. In summary, the observed alteration of islet morphology and of GLUT2 expression in diabetic mice complements our previous results from a superfusion protocol and further clarifies the mechanisms of diabetogenesis in NZO mice.  相似文献   
309.
Sniff nasal inspiratory pressure (SNIP) measurement is a volitional noninvasive assessment of inspiratory muscle strength. A maximum of 10 sniffs is generally used. The purpose of the present study was to investigate whether the maximum SNIP improved after the tenth sniff. In total, 20 healthy volunteers and 305 patients with various neuromuscular and lung diseases were encouraged to perform 40 and 20 sniffs, respectively. The best SNIP among the first 10 sniffs was lower than the best SNIP among the next 10 sniffs in the healthy volunteers and patients. The SNIP improvement after the twentieth sniff was marginal. In conclusion, a learning effect persists after the tenth sniff. The current authors suggest using 10 additional sniffs when the best result of the first 10 sniffs is slightly below normal, or when sniff nasal inspiratory pressure is used to monitor a progressive decline in inspiratory muscle strength.  相似文献   
310.
Levels of the soluble form of the triggering receptor expressed on myeloid cells (sTREM)-1 are elevated in severe sepsis. However, it is not known whether sTREM-1 measurements can distinguish milder bacterial infections from noninfectious inflammation. The present authors studied whether serum sTREM-1 levels differ in community-acquired pneumonia, exacerbations of chronic obstructive pulmonary disease (COPD), asthma and controls, and whether sTREM-1 may be used as a surrogate marker for the need for antibiotics. Serum sTREM-1 levels in 150 patients with pneumonia, COPD and asthma exacerbations and 62 healthy controls were measured. Serum sTREM-1 levels were significantly elevated in pneumonia (median 295.2 ng x mL(-1)), COPD (280.3 ng x mL(-1)) and asthma exacerbations (184.0 ng x mL(-1)) compared with controls (83.1 ng x mL(-1)). Levels were higher in pneumonia and Anthonisen type 1 COPD exacerbations than in type 2 and 3 COPD and asthma exacerbations. The area under the receiver operating characteristics curve for sTREM-1 as a surrogate marker for the need for antibiotics was 0.77. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 were elevated predominantly in pneumonia and Anthonisen type 1 COPD exacerbations versus type 2 and 3 chronic obstructive pulmonary disease exacerbations, asthma and controls. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 has moderate but insufficient accuracy as a surrogate marker for the need for antibiotics in lower respiratory tract infections.  相似文献   
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