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41.
After a two-hour period of regional intestinal shock (arterial inflow pressure 30 to 35 mm Hg; electrical stimulation of regional vasoconstrictor fibers at 6 Hz) a pronounced cardiovascular derangement is observed as reflected in a rapid fall in arterial blood pressure. In this study, central hemodynamics and lung function were investigated to elucidate if functional changes in the thoracic organs might explain the cardiovascular collapse. No alteration of pulmonary function was observed. A negative inotropic influence on the heart was, however, noted as judged by a decreased left ventricular stroke volume and left ventricular maximal pressure change in the face of an increased left ventricular end diastolic pressure. Based on earlier observations with the same shock model, it is proposed that the cardiac effects were caused by cardiotoxic material released from the hypoxic gut. 相似文献
42.
Haglund J Haiman M Loehr N 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(8):2690-2696
Haglund recently proposed a combinatorial interpretation of the modified Macdonald polynomials H(mu). We give a combinatorial proof of this conjecture, which establishes the existence and integrality of H(mu). As corollaries, we obtain the cocharge formula of Lascoux and Schutzenberger for Hall-Littlewood polynomials, a formula of Sahi and Knop for Jack's symmetric functions, a generalization of this result to the integral Macdonald polynomials J(mu), a formula for H(mu) in terms of Lascoux-Leclerc-Thibon polynomials, and combinatorial expressions for the Kostka-Macdonald coefficients K(lambda,mu) when mu is a two-column shape. 相似文献
43.
Otterblad Olausson P Haglund B Ringbäck Weitoft G Cnattingius S 《BJOG : an international journal of obstetrics and gynaecology》2004,111(8):793-799
OBJECTIVE: Some data suggest an association between teenage childbearing and premature death. Whether this possible increase in risk is associated with social circumstances before or after childbirth is not known. We studied premature death in relation to age at first birth, social background and social situation after first birth. DESIGN: Population-based cohort study. SETTING: Women born in Sweden registered in the 1985 Swedish Population Census. POPULATION: Swedish women born 1950-1964 who had their first infant before the age of 30 years (N= 460,434). METHODS: Information on the women's social background and social situation after first birth was obtained from Population Censuses. The women were followed up with regard to cause of death from December 1, 1990 to December 31, 1995. Mortality rate ratios and 95% confidence intervals (CI) were calculated. MAIN OUTCOME MEASURES: Mortality rates by cause of death. RESULTS: Independent of socio-economic background, teenage mothers faced an increased risk of premature death later in life compared with older mothers (rate ratio 1.6, 95% CI 1.4-1.9). The increased risk was most evident for deaths from cervical cancer, lung cancer, ischaemic heart disease, suicide, inflicted violence and alcohol-related diseases. Some, but not all, of these increases in risk were associated with the poorer social position of teenagers mothers. CONCLUSIONS: Teenage mothers, independent of socio-economic background, face an increased risk of premature death. Strategies to reduce teenage childbearing are likely to contribute to improved maternal and infant health. 相似文献
44.
Haglund J 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(46):16127-16131
We introduce a polynomial C(mu)[Z; q, t], depending on a set of variables Z = z(1), z(2),..., a partition mu, and two extra parameters q, t. The definition of C(mu) involves a pair of statistics (maj(sigma, mu), inv(sigma, mu)) on words sigma of positive integers, and the coefficients of the z(i) are manifestly in N[q,t]. We conjecture that C(mu)[Z; q, t] is none other than the modified Macdonald polynomial H(mu)[Z; q, t]. We further introduce a general family of polynomials F(T)[Z; q, S], where T is an arbitrary set of squares in the first quadrant of the xy plane, and S is an arbitrary subset of T. The coefficients of the F(T)[Z; q, S] are in N[q], and C(mu)[Z; q, t] is a sum of certain F(T)[Z; q, S] times nonnegative powers of t. We prove F(T)[Z; q, S] is symmetric in the z(i) and satisfies other properties consistent with the conjecture. We also show how the coefficient of a monomial in F(T)[Z; q, S] can be expressed recursively. maple calculations indicate the F(T)[Z; q, S] are Schur-positive, and we present a combinatorial conjecture for their Schur coefficients when the set T is a partition with at most three columns. 相似文献
45.
OBJECTIVES: To investigate social and gender equality in access to coronary revascularization for those treated for coronary heart disease in Sweden between 1991 and 2000. DESIGN: All Swedish residents between 25 and 74 years old with a hospital stay for coronary heart disease were eligible for the study, in total about 153,000 persons. The Swedish Hospital Discharge Register from 1988 through 2000 was used to define the study population. Poisson regression analyses were used to estimate the effect of socio-economic status on the likelihood for coronary artery bypass grafting (CABG) within 2 years. In the analysis of gender differences, the likelihood for percutaneous coronary intervention (PCI) was also included. RESULTS: Males were 1.5 times more likely to undergo revascularization procedures than females even after adjusting for confounding factors and the fact that women are less eligible for interventions. The analyses also showed significant socio-economic inequalities in access to CABG among men, but not among women. CONCLUSIONS: There are gender and socio-economic inequalities in access to cardiac procedures in Sweden. 相似文献
46.
Prognostic value of syndecan-1 expression in breast cancer 总被引:4,自引:0,他引:4
OBJECTIVE: Syndecan-1 is a cell surface heparan sulphate proteoglycan which participates in cell proliferation, cell migration and cell-matrix interactions. Epithelial syndecan-1 expression is reduced in several malignant tumours, but in breast and pancreatic cancer, increased expression has also been described. Loss of epithelial syndecan-1 has been associated with poor prognosis in some forms of cancer, but previous findings in breast cancer have been contradictory. The objective of this study was to evaluate the prognostic value of the immunohistochemical expression of syndecan-1 in a series of 200 patients with invasive breast cancer with a median follow-up of 17 years. METHODS: Formalin-fixed paraffin-embedded specimens were stained using a monoclonal antibody against syndecan-1. RESULTS: Syndecan-1 was expressed in the epithelium in 61% and in the stroma in 67% of the tumours. Epithelial syndecan-1 expression was associated with negative oestrogen receptor (ER) status (p < 0.01), and stromal syndecan-1 expression with positive ER status (p = 0.02). The breast cancer-specific 10-year overall survival for patients with epithelial syndecan-1 expression was 65%, compared with 82% for those with loss of epithelial expression (p = 0.02). Ten-year survival was 66% for those expressing stromal syndecan-1 and 83% for those lacking stromal expression (p = 0.15). Patients with both epithelial and stromal expression had a 10-year survival of only 56%, compared to 78% in patients with other expression pattern combinations (p < 0.002). In Cox multivariate analysis, only axillary involvement and tumour size were significant predictors of breast cancer-specific survival. CONCLUSION: Concomitant expression of syndecan-1 in both epithelium and stroma may be a predictor of unfavourable prognosis in breast cancer, and in contrast with previous studies, loss of epithelial syndecan-1 was associated with a more favourable prognosis. 相似文献
47.
48.
Wiksten JP Lundin J Nordling S Lundin M Kokkola A von Boguslawski K Haglund C 《Oncology》2003,64(3):245-250
OBJECTIVES: Tenascin-C is a hexameric extracellular matrix glycoprotein that is expressed during embryonic development and re-expressed in proliferative processes such as wound healing and tumorigenesis. Stromal tenascin-C may block tumor invasion and thus have a significant influence on tumor spread and prognosis. METHODS: In the present study, tissue expression of stromal tenascin-C was studied by immunohistochemistry in a series of 314 patients with gastric cancer. RESULTS: Strong tenascin-C positivity was seen in the stroma of the tumor in 122 (39%) cases. There was a correlation between strong tenascin-C expression and low stage (p = 0.002), superficial tumor penetration (p = 0.02), location of tumor at the distal third of the stomach (p = 0.03), and potentially curative surgery (p = 0.008). No significant correlation was found between tenascin-C positivity and nodal status, distant metastases, age, Laurén classification, gender, tumor size, or Borrmann classification. The cumulative 5-year survival in patients with strong tenascin-C expression was 42% compared to 26% in those with negative-to-moderate expression (p = 0.0053). In multivariate survival analysis stratified for estimated cure of surgery, stage of disease was the only independent prognostic factor. CONCLUSION: In conclusion, tenascin-C expression seems to correlate with cancer related survival in patients with gastric cancer, but may not add significant prognostic information to that provided by TNM stage. 相似文献
49.
50.
Epithelial and stromal syndecan-1 expression as predictor of outcome in patients with gastric cancer 总被引:11,自引:0,他引:11
Wiksten JP Lundin J Nordling S Lundin M Kokkola A von Boguslawski K Haglund C 《International journal of cancer. Journal international du cancer》2001,95(1):1-6
The prognostic value of the immunohistochemical expression of epithelial and stromal syndecan-1 was evaluated in 296 patients with gastric carcinoma. Formalin-fixed, paraffin-embedded specimens of gastric adenocarcinomas were stained with mouse monoclonal antibody B-B4 against human syndecan-1. Loss of immunoreactivity (syndecan-1 immunoreactivity correlated with a higher stage of disease (stages II-IV), tumour location in the upper third of the stomach, nodal metastases (N1 or N2), positive stromal syndecan-1 staining, deep tumour penetration (to subserosa or deeper = T2-T4), larger tumour size (> or = 5 cm) and intestinal type of cancer. No correlation between epithelial syndecan-1 immunoreactivity and age, gender, distant metastases, grade of differentiation or Borrmann classification was observed. Positive stromal syndecan-1 immunoreactivity correlated with decreased epithelial syndecan-1 expression, intestinal type of cancer and Borrmann type I. Patients with low epithelial syndecan-1 expression in cancer cells had worse overall survival than patients with strong epithelial syndecan-1 staining (p = 0.0012). Stromal syndecan-1-positive patients had a worse outcome than patients with syndecan-1-negative stroma (p = 0.0193). In Cox multivariate analysis, stromal syndecan-1 immunoreactivity was a prognostic factor independent of TNM stage, surgery for cure and tumour size. Thus, the immunohistochemical expression of syndecan-1 might be a predictor of outcome in patients with gastric adenocarcinoma. 相似文献