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排序方式: 共有736条查询结果,搜索用时 15 毫秒
1.
D. J. Lederer S. M. Arcasoy R. G. Barr J. S. Wilt E. Bagiella F. D'Ovidio J. R. Sonett S. M. Kawut 《American journal of transplantation》2006,6(10):2436-2442
We previously reported poorer survival among non-Hispanic blacks and Hispanics with idiopathic pulmonary fibrosis (IPF) compared to non-Hispanic whites at our center. In the current study, we hypothesized that these disparities would exist in a nationwide cohort of wait-listed patients with IPF. We performed a retrospective cohort study of 2635 patients with IPF listed for lung transplantation between 1995 and 2003 at 94 transplant centers in the United States. The age-adjusted mortality rate was higher among non-Hispanic blacks [hazard ratio (HR) = 1.24, 95% confidence interval (CI) 1.06-1.45, p = 0.009] and Hispanics (HR = 1.29, 95% CI 1.06-1.56, p = 0.01) compared to non-Hispanic whites. These findings persisted after adjustment for transplantation, medical comorbidities and socioeconomic status. Worse lung function at the time of listing appeared to explain some of these differences (HR for non-Hispanic blacks after adjustment for forced vital capacity percent predicted = 1.16, 95% CI 0.98-1.36, p = 0.09; HR for Hispanics = 1.21, 95% CI 0.99-1.48, p = 0.056). In summary, black and Hispanic patients with IPF have worse survival than whites after listing for lung transplant. 相似文献
2.
Repair of large midline incisional hernias with polypropylene mesh: Comparison of three operative techniques 总被引:9,自引:0,他引:9
de Vries Reilingh TS van Geldere D Langenhorst BLAM de Jong D van der Wilt GJ van Goor H Bleichrodt RP 《Hernia》2004,8(1):56-59
Polypropylene mesh is widely used for the reconstruction of incisional hernias that cannot be closed primarily. Several techniques have been advocated to implant the mesh. The objective of this study was to evaluate, retrospectively, early and late results of three different techniques, onlay, inlay, and underlay. The records of 53 consecutive patients with a large midline incisional hernia — 25 women and 28 men, mean age 60.4 (range 28–94) — were reviewed. Polypropylene mesh was implanted using the onlay technique in 13 patients, inlay in 23 patients, and underlay in 17 patients. Either the greater omentum or a polyglactin mesh was interponated between the mesh and the viscera. The records of these 53 patients were reviewed with respect to: size and cause of the hernia, pre- and postoperative mortality and morbidity, with special attention to wound complications. Patients were invited to attend the outpatient clinic at least 12 months after implantation of the mesh for physical examination of the abdominal wall. Postoperative complications occurred in 14 (26.4%) patients. The onlay technique had significantly more complications, as compared to both other techniques. Reherniation occurred in 15 (28.3%) patients. The reherniation rate of the inlay technique was significantly higher than after the underlay technique (44% vs 12%, P=0.03) and tended to be higher than the onlay technique (44% vs 23%, P=0.22). Repair of large midline incisional hernias with the use of a polypropylene mesh carries a high risk of complications and has a high reherniation rate. The underlay technique seems to be the better technique. 相似文献
3.
Brian F O'Donnell Marcia A Wilt Ann Marie Hake Julie C Stout Sandra C Kirkwood Tatiana Foroud 《Movement disorders》2003,18(9):1027-1034
Disturbances of visual cognition, visuomotor performance, and visual memory have been described frequently in Huntington's disease (HD). Early stage visual abnormalities could contribute to these deficits. We evaluated visual processing in 20 control subjects who were non-gene carriers at risk for HD, nine presymptomatic gene-positive subjects, and eight subjects with a recent diagnosis of Huntington's disease. Visual perceptual tests of contrast sensitivity and motion discrimination were used to probe early stage visual processing. Extraocular movements were evaluated in a neurologic examination, and the Digit Symbol test was used to test visual motor performance. Contrast sensitivity did not differ among the three groups. Motion discrimination was impaired in HD subjects but not in the presymptomatic gene carriers when compared to gene noncarriers. Among gene carriers, impaired motion discrimination performance was associated with poorer Digit Symbol performance and extraocular abnormalities. These findings suggest that the early stages of HD are associated with disturbances of motion perception as well as disruptions of visual motor and ocular motor performance. 相似文献
4.
Mulkerrin EC; Clark BA; Epstein FH 《QJM : monthly journal of the Association of Physicians》1997,90(6):411-415
We studied blood pressure and natriuretic responses to acute salt loading,
and the effect of non-steroidal anti-inflammatory agents on these
responses, in five healthy normotensive women aged 65 to 71 years. Five
women aged 25 to 31 years acted as controls. Intravenous saline loading,
with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h.
Baseline blood pressures were higher in the elderly. Saline infusion
without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in
the older group only. Ibuprofen increased baseline SBP in the elderly (129
+/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen
again raised blood pressure by about 25 mmHg in the elderly only. The
elderly group showed markedly increased sodium excretion during saline
loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP
or sodium excretion in controls. Ageing appears to increase susceptibility
to salt retention and hypertension from non-steroidal anti-inflammatory
agents.
相似文献
5.
Acute thoracic aortic dissection has a high mortality if untreated, so the diagnosis must be rapidly made if mortality is to be lowered significantly. Multiple imaging techniques are often used. This retrospective study from 1988 to 1993 assesses the usefulness in diagnosis of chest X-rays, computed tomography (CT) scanning, aortography, magnetic resonance imaging (MRI), trans-thoracic (TTE) and trans-oesophageal (TOE) echocardiography. Forty-two patients with a final clinical diagnosis of dissection were studied. The diagnosis was confirmed in 16 (13 at surgery and three at autopsy). Three died with dissection given as the only cause for death. Chest X-ray abnormalities were seen in all 19 patients with surgery or death from dissection, with a widened mediastinum and/or dilated aorta being present in 17. In the group of 16 patients with surgery or autopsy proof, CT scans found dissections in 9 of 12 patients studied and correctly classified the type in only five. Aortography was performed in five, with accurate depiction of dissection and type in all. TTE found dissections in three of eight patients imaged by this method. MRI and TOE were performed each on two patients, with accurate depiction of dissection and type in each. Because of the relatively low sensitivity of CT scanning in defining aortic dissections Westmead Hospital is currently assessing the use of TOE as the prime imaging modality prior to surgical intervention. 相似文献
6.
Castillo S Reyes G Tejedor D Mozas P Suarez Y Lasuncion MA Cenarro A Civeira F Alonso R Mata P Pocovi M;Spanish Group of FH 《Human mutation》2002,20(6):477
Familial hypercholesterolemia is a genetic disorder caused by mutations in the LDL receptor gene. During a survey of mutations of LDL receptor gene in Spanish FH patients we found two mutations in the same allele: a missense N543H mutation in exon 11 and a 9bp inframe deletion (2393del9) located in exon 17. This double mutant allele was founded in 10 out of 458 unrelated patients: one homozygous FH [N543H+2393del9] + [N543H+2393del9], one compound heterozygote [N543H+2393del9] + [W-18X+E256K] and 8 heterozygotes. Flow cytometric analysis showed a defective LDL binding (20% of normal value) and internalization (23%) in lymphocytes from the homozygous patient; furthermore, studies of mitogen-stimulated lymphocytes demonstrated that the ability of LDL to support cell proliferation was impaired. Unexpectedly, not all carriers of the double mutant allele develop hypercholesterolemia and, furthermore, cholesterol-lowering treatment of the homozygous patient resulted in a 58% LDL cholesterol reduction. In conclusion, the phenotypic expression in the homozygous and heterozygous patients presented here, as well as the LDL-receptor residual activity, allowed the classification of this mutation as mild extending the group of mild mutations found at homozygosity. 相似文献
7.
Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP) 总被引:8,自引:0,他引:8
Rowe PS; Oudet CL; Francis F; Sinding C; Pannetier S; Econs MJ; Strom TM; Meitinger T; Garabedian M; David A; Macher MA; Questiaux E; Popowska E; Pronicka E; Read AP; Mokrzycki A; Glorieux FH; Drezner MK; Hanauer A; Lehrach H; Goulding JN; O'Riordan JL 《Human molecular genetics》1997,6(4):539-549
Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with
homologies to endopeptidases, on the X-chromosome), are responsible for
X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family
of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has
raised important questions regarding PEX function at the molecular level.
The aim of this study was to analyse 99 HYP families for PEX gene
mutations, and to correlate predicted changes in the protein structure with
Zn2+ metallopeptidase gene function. Primers flanking 22 characterised
exons were used to amplify DNA by PCR, and SSCP was then used to screen for
mutations. Deletions, insertions, nonsense mutations, stop codons and
splice mutations occurred in 83% of families screened for in all 22 exons,
and 51% of a separate set of families screened in 17 PEX gene exons.
Missense mutations in four regions of the gene were informative regarding
function, with one mutation in the Zn2+-binding site predicted to alter
substrate enzyme interaction and catalysis. Computer analysis of the
remaining mutations predicted changes in secondary structure,
N-glycosylation, protein phosphorylation and catalytic site molecular
structure. The wide range of mutations that align with regions required for
protease activity in NEP suggests that PEX also functions as a protease,
and may act by processing factor(s) involved in bone mineral metabolism.
相似文献
8.
Michael M. Milks Stephen R. Wilt Ibrahim Ali Michael A. Pereira Daniel Couri 《Archives of toxicology》1982,51(1):27-35
The initiating and promoting activities of 1,2-dibromoethane in rat liver were investigated using the enzyme-altered foci bioassay. The incidence of -glutamyl-transpeptidase (GGT)-positive foci was used as an early histochemical marker for hepatocarcinogenesis. To determine the initiating activity of 1,2-dibromoethane, the halogenated hydrocarbon was administered orally in corn oil as single or multiple doses (60 or 120 mg/kg) either before or after partial hepatectomy. The animals were then given a promoting regimen of 500 ppm phenobarbital in their drinking water. No increase in the incidence of GGT-positive foci was observed in any of the 1,2-dibromoethane initiation groups. The tumor promoting activity of 1,2-dibromoethane was determined in partially hepatectomized rats which were initiated with N-nitrosodiethylamine (30 mg/kg; po), and one week later were administered 1,2-dibromoethane (10 or 30 mg/kg) orally in corn oil five times weekly for 8 weeks. Control groups receiving sham hepatectomy or no initiator were also treated with the halogenated hydrocarbon five times weekly. Only in those animals which received partial hepatectomy, N-nitrosodiethylamine initiation, and 1,2-dibromoethane was the incidence of GGT-positive foci significantly increased. These results do not support significant initiator activity of 1,2-dibromoethane in rat liver, but do indicate that 1,2-dibromoethane possesses promoter activity which may contribute to its carcinogenic activity. 相似文献
9.
M G A van Ijken B van Etten F Brunstein T L M ten Hagen G Guetens J H W de Wilt E A de Bruijn A M M Eggermont 《European journal of surgical oncology》2005,31(8):807-816
AIMS: To review the development and current status of balloon catheter mediated hypoxic perfusion of abdomen, pelvis and liver for treatment of locally advanced malignancies. Within this context we focus on the addition of tumour necrosis factor-alpha (TNF) to these minimal invasive perfusion procedures. METHODS: A literature search on these topics was carried out in PubMed for indexed articles and in all issues of Regional Cancer Treatment. The findings were related to our own experiences. RESULTS: Hypoxic abdominal (HAP) and hypoxic pelvic perfusion (HPP) using balloon catheters, are currently applied modalities for treatment of a wide variety of abdominal and pelvic tumours, yet scientific validation of these procedures is poor. Following the results of several Phase I-II trials, both treatments are associated with severe systemic toxicity, significant morbidity and even mortality. The degree of systemic leakage associated with these procedures prohibits addition of TNF. For leakage free liver perfusion surgery is still required, as with current balloon catheter techniques it is not possible to perform leakage free isolated hypoxic hepatic perfusion (IHHP), using either orthograde or retrograde hepatic flow. Experimental and clinical observations suggest that within any perfusion setting, the utilization of TNF is only indicated for treatment of highly vascularised tumours and not for treatment of colorectal tumours. CONCLUSION: Balloon catheter technology in its present form does not provide adequate leakage control in any of these settings and is therefore associated with considerable toxicity. It is associated with poor response rates and cannot be considered in any setting as a standard of care. 相似文献
10.
W Kievit M J Bolster G J van der Wilt P Bult F B J M Thunnissen J Meijer L J A Strobbe J H G Klinkenbijl T Wobbes E M M Adang L V A M Beex V C G Tjan-Heijnen 《Annals of oncology》2005,16(12):1874-1881
BACKGROUND: In this study, the potential impact of a new national guideline for adjuvant systemic therapy in breast cancer (introduced in The Netherlands in 1998) was assessed, as well as the modifications of this guideline, issued in 2001. Both the change in total number of patients eligible for adjuvant therapy, as well as the cost-effectiveness of the changed clinical management of these patients were analysed. PATIENTS AND METHODS: Percentages of patients who would be eligible for adjuvant therapy in 1994, 1998 and 2001 were estimated, based on clinical data from 127 patients, who were operated on in 1994. Ten-year overall survival rates were used as a measure of effectiveness, based on the two most recent EBCTCG meta-analyses. Actual resource costs were calculated. With a decision analytic model, the incremental cost-effectiveness ratios (1998 versus 1994, and 2001 versus 1998) were calculated. RESULTS: The introduction of the 1998 guideline resulted in a relative increase of 80% in the total number of patients eligible for adjuvant therapy, compared with 1994 (from 40% to 72% of all patients with primary breast cancer). With an estimated absolute increase of 10-year overall survival of 2%, the 1998 guideline was found to have an expected incremental cost-effectiveness ratio of about 4837 per life-year gained. CONCLUSIONS: Introduction of the new guideline considerably affected the number of patients eligible for adjuvant systemic therapy for breast cancer. The associated incremental cost-effectiveness ratio is well within the range of values that are generally considered acceptable. 相似文献