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排序方式: 共有382条查询结果,搜索用时 15 毫秒
71.
MD Savvidou R Akolekar E Zaragoza LC Poon KH Nicolaides 《BJOG : an international journal of obstetrics and gynaecology》2009,116(5):643-647
Objective To compare urinary placental growth factor (PlGF) concentration at 11+0 to 13+6 weeks of gestation in women who subsequently develop pre-eclampsia with normotensive controls.
Design Nested case–control study within a prospective study for first trimester prediction of pre-eclampsia.
Setting Routine antenatal visit in a teaching hospital.
Population Fifty-two women who developed pre-eclampsia and 52 controls matched for gestational age and sample storage time.
Methods Urinary PlGF concentration and PlGF to creatinine ratio were measured in women who developed pre-eclampsia and their matched controls. Comparisons between groups were performed using Student's t test.
Main outcome measures Development of pre-eclampsia.
Results In the pre-eclampsia group, the median urinary PlGF concentration (20.6 pg/ml, interquartile range [IQR] 9.1–32.0 pg/ml) and median urinary PlGF to creatinine ratio (1.6 pg/mg, IQR 1.2–2.5 pg/mg) were not significantly different from the control group (11.8 pg/ml, IQR 5.5–29.8 pg/ml, P = 0.1 and 1.7 pg/mg, IQR 1.2–2.3 pg/mg, P = 0.3, respectively). There were no significant differences between women with early-onset pre-eclampsia requiring delivery before 34 weeks ( n = 13) and those with late-onset pre-eclampsia ( n = 39) and between women with pre-eclampsia and fetal growth restriction (FGR) ( n = 25) and those with pre-eclampsia and no FGR ( n = 27) in either median PlGF concentration or median urinary PlGF to creatinine ratio.
Conclusions The development of pre-eclampsia is not preceded by altered urinary PlGF concentration in the first trimester of pregnancy. 相似文献
Design Nested case–control study within a prospective study for first trimester prediction of pre-eclampsia.
Setting Routine antenatal visit in a teaching hospital.
Population Fifty-two women who developed pre-eclampsia and 52 controls matched for gestational age and sample storage time.
Methods Urinary PlGF concentration and PlGF to creatinine ratio were measured in women who developed pre-eclampsia and their matched controls. Comparisons between groups were performed using Student's t test.
Main outcome measures Development of pre-eclampsia.
Results In the pre-eclampsia group, the median urinary PlGF concentration (20.6 pg/ml, interquartile range [IQR] 9.1–32.0 pg/ml) and median urinary PlGF to creatinine ratio (1.6 pg/mg, IQR 1.2–2.5 pg/mg) were not significantly different from the control group (11.8 pg/ml, IQR 5.5–29.8 pg/ml, P = 0.1 and 1.7 pg/mg, IQR 1.2–2.3 pg/mg, P = 0.3, respectively). There were no significant differences between women with early-onset pre-eclampsia requiring delivery before 34 weeks ( n = 13) and those with late-onset pre-eclampsia ( n = 39) and between women with pre-eclampsia and fetal growth restriction (FGR) ( n = 25) and those with pre-eclampsia and no FGR ( n = 27) in either median PlGF concentration or median urinary PlGF to creatinine ratio.
Conclusions The development of pre-eclampsia is not preceded by altered urinary PlGF concentration in the first trimester of pregnancy. 相似文献
72.
P-selectin is a 140-kD protein found in the alpha-granules of platelets and the Weibel-Palade bodies of endothelial cells that on cell activation is expressed on the cell surface and also secreted into the plasma. The secreted form of P-selectin, like plasma P-selectin, differed from platelet membrane P-selectin in that its molecular mass was approximately 3 kD lower under reducing conditions. Both the secreted and plasma forms of P-selectin contained cytoplasmic sequence as determined by Western blot analysis with an affinity-purified rabbit anti-P-selectin cytoplasmic peptide antibody. We have measured plasma P- selectin and beta-thromboglobulin (beta TG) concurrently in (1) patients with consumptive thrombotic disorders, including disseminated intravascular coagulation (DIC), heparin-induced thrombocytopenia (HIT), and thrombotic thrombocytopenic purpura (TTP)/haemolytic uremic syndrome (HUS); (2) patients with idiopathic thrombocytopenic purpura (ITP); and (3) healthy controls. Patients with DIC, HIT, and TTP/HUS, but not ITP, had significantly elevated plasma P-selectin and beta TG levels when compared with their age-matched healthy controls. The increased plasma P-selectin and beta TG in patients with thrombotic disorders were likely to be the result of in vivo platelet and endothelial cell damage or activation. We also found that avoidance of veno-occlusion and other tedious measures customarily taken during blood collection and sample preparation to prevent in vitro platelet activation did not affect plasma P-selectin assay results. In addition, plasma P-selectin levels were not influenced by the presence of renal failure or heparin administration. These results indicate that plasma P- selectin may be a useful new marker for thrombotic diseases. 相似文献
73.
Direct demonstration that autologous bone marrow transplantation for solid tumors can return a multiplicity of tumorigenic cells 总被引:5,自引:2,他引:5
Rill DR; Santana VM; Roberts WM; Nilson T; Bowman LC; Krance RA; Heslop HE; Moen RC; Ihle JN; Brenner MK 《Blood》1994,84(2):380-383
Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow. 相似文献
74.
Forty-one proved cases of acute acalculous cholecystitis imaged with technetium-99m iminodiacetic acid (IDA) cholescintigraphy were retrospectively analyzed. After the exclusion of one indeterminate scan (showing poor initial hepatic uptake and excretion), the study yielded a 92.5% (37 of 40) sensitivity for the detection of cystic or common bile duct obstruction. Each of the three patients with false-negative scintigrams had other abnormal scintigraphic findings suggestive of biliary tract disease. Of the 20 patients (48.8%) with focal or diffuse gangrenous cholecystitis or perforation, seven (35%) exhibited either free peritoneal spill or increased pericholecystic activity to indicate the presence of advanced disease. 相似文献
75.
Independent prognostic significance of a nuclear proliferation antigen in diffuse large cell lymphomas as determined by the monoclonal antibody Ki-67 总被引:12,自引:0,他引:12
Grogan TM; Lippman SM; Spier CM; Slymen DJ; Rybski JA; Rangel CS; Richter LC; Miller TP 《Blood》1988,71(4):1157-1160
To assess the prognostic significance of the growth fraction in diffuse large cell lymphoma (DLCL), we studied 105 DLCL patients with the monoclonal antibody Ki-67 applied to frozen tissue sections. Ki-67 detects a nuclear antigen associated with cell proliferation not found in resting cells. Ki-67 findings and other clinical prognostic factors were correlated with outcome using univariate and multivariate analyses in the proportional hazards model. High proliferative activity, defined as nuclear Ki-67 expression in greater than 60% of malignant cells (Ki- 67 greater than 60), was found to be a strong predictor of poor survival among these patients (P = .003, log-rank). The 19 patients with Ki-67 greater than 60% had a median survival of 8 months compared with a median survival of 39 months for the 86 patients with Ki-67 less than or equal to 60%. Examination of pretreatment clinical variables indicated the patient groups were similar with regard to age, sex, stage, B symptoms, tumor bulk, and lactate dehydrogenase (LDH). Both patient groups received comparable curative intent therapy and showed comparable complete response rate precluding treatment differences as modifying outcome. Multivariate analysis indicated Ki-67 is an independent predictor of survival (multivariate P = .006). Further statistical analysis using only B-cell DLCL patients treated with CHOP (63 patients) indicated that Ki-67 greater than 60 retained strong prediction of poor outcome (P = .002, log-rank) among this homogeneous group. We conclude that high proliferative activity (Ki-67 greater than 60) is an independent factor allowing laboratory prediction of probable poor outcome of DLCL. 相似文献
76.
Lymphocyte phenotype and lymphokines following anti-thymocyte globulin therapy in patients with aplastic anaemia 总被引:1,自引:0,他引:1
Leonidas Platanias Pedro Gascon Leonard Bielory Patricia Griffith Arthur Nienhuis Neal Young 《British journal of haematology》1987,66(4):437-443
Twenty-two patients with adult onset aplastic anaemia were analysed before and after therapy with anti-thymocyte globulin (ATG). Lymphocyte phenotype, lymphokine levels or production, and haematopoietic progenitor cell number were measured 3 months after therapy; clinical response was determined 1 year post-therapy. By flow cytometry there was a significant reduction in both the proportion and absolute number of peripheral blood lymphocytes expressing activation antigen Tac (IL-2 receptor) and in the proportion of HLA-DR+ lymphocytes. For T cells bearing HLA-DR, there were proportional decreases in both activated helper and suppressor cells. There was no statistically significant difference pre-ATG to post-ATG in the absolute numbers of total, helper and suppressor lymphocytes. In all 10 haematologic responders the number of Tac bearing lymphocytes after ATG therapy was in the normal range, but half of 12 non-responding patients continued to have abnormally elevated numbers of Tac+ T cells. The proportion of Tac+ cells were not related to transfusion history. Gamma-interferon levels in serum by radioimmunoassay were elevated in almost half the aplastic patients; post-ATG, gamma-interferon was detectable in only three patients. Haematologic response to ATG therapy was associated with increased numbers of haematopoietic progenitors post-treatment, but pre-treatment values were not predictive of a response. These results are consistent with a pathogenic role for activated T-cells and their lymphokine products and suggest that the target of ATG therapy may be a Tac+ lymphocyte. 相似文献
77.
R Morley BA Baker LC Greene MBE Livingstone PSEG Harland A Lucas 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(12):1230-1234
Serum lipid and lipoprotein cholesterol levels track from childhood and are associated with risk of coronary heart disease. There is some evidence that these are influenced by dietary intake and exercise. Serum lipid and lipoprotein cholesterols were measured in a cohort of 119 British children aged 12–15 y who completed a dietary assessment and exercise questionnaire. The ratio of total- to high-density lipoprotein cholesterol fell with increasing fibre intake, but after adjustment for age, body mass index, sex and other dietary factors, this was not statistically significant. Children exercising at least once a day had significantly lower serum total cholesterol and low density lipoprotein cholesterol levels than those exercising less frequently, even after adjustment for the above factors and dietary fibre intake. No dietary factor was significantly associated with any lipid measure after adjustment for the above factors. The challenge is how to optimize exercise level in adolescent children. 相似文献
78.
Colchicine for recurrent pericarditis in children 总被引:4,自引:0,他引:4
The incidence of recurrence of acute pericarditis in children varies from 15% to 30% and is accompanied by a high morbidity. Various treatment modalities have been used with variable success rates and side effects. La Serna et al. (Lancet 1987; 26: 1517) were the first to treat adults with recurrent pericarditis with colchicine, and were followed by other authors. To our knowledge no studies in children have been reported. In this paper, we present three children who suffered from viral or idiopathic recurrent pericarditis, despite multiple courses of non-steroidal anti-inflammatory drugs (NSAIDs) and/or corticosteroids. They responded remarkably well to colchicine, which was administered for 6 months with no adverse reactions. They continue to do well 18, 11 and 12 months after cessation of treatment, respectively. 相似文献
79.
Induced drug resistance inhibits selection of initiated cells and cancer development 总被引:1,自引:1,他引:0
Compounds exerting a mitoinhibitory effect on normal hepatocytes are potent
promoters in the resistant hepatocyte model of chemical carcinogenesis in
combination with stimulation of regenerative growth by partial hepatectomy
or treatment with carbon tetrachloride. 2- Acetylaminofluorene (2-AAF)
almost completely inhibits liver cell regeneration after partial
hepatectomy, allowing only resistant cells to participate in regenerative
growth. After initiation by diethylnitrosamine and promotion with 2-AAF and
partial hepatectomy (PH), focal growth of initiated cells generates liver
lesions which occupy 40% of the hepatic volume three weeks after PH. In
this work the mechanism for the anti promoting effects of phenobarbital and
3- methylcholantrene were investigated as well as their effects on the
development of malignant hepatocellular carcinoma in the resistant
hepatocyte model. Treatment with phenobarbital or, especially, 3-
methylcholanthrene rendered normal rat hepatocytes resistant to the
mitoinhibitory effect of 2-AAF. In combination with 2-AAF/PH, 3-
methylcholanthrene shortened the regenerative growth period to less than
one week. In the Solt-Farber protocol for experimental
hepatocarcinogenesis, treatment with phenobarbital or 3- methylcholanthrene
during promotion with 2-AAF/PH permitted hepatocytes surrounding the focal
lesions to respond with regenerative growth. The foci and surrounding liver
grew until the liver/body mass index reached the control value. With
phenobarbital treatment the total focal volume was 20% of the liver volume
three weeks after PH, whereas the corresponding value in the case of
3-methylcholanthrene was only 1%. Labelling index data supported the
conclusion that growth of the liver lesions in the resistant hepatocyte
model was dependent on differential inhibition of normal hepatocyte growth
by the promoter and that the size of the foci obtained was related to the
length of time after PH required to complete liver regeneration.
3-methylcholanthrene induced 2- AAF resistance prevented the development of
large persistent nodules and hepatocellular carcinoma while phenobarbital
delayed cancer development with several month. The data thus supports the
idea that the degree of clonal expansion during promotion determines the
size of the population at risk for malignant transformation, as well as the
final frequency of carcinomas.
相似文献
80.