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991.
992.
OBJECTIVE: To evaluate the differences in the presentations of women with and without a prior history of an ectopic pregnancy and a suspicion of a current ectopic. STUDY DESIGN: Evaluation of a cohort of patients presenting to an emergency department to exclude an ectopic pregnancy. Over a 58-month study period (January 1992-October 1996), 1,510 consecutive, pregnant women presenting to an emergency department with pelvic pain and/or vaginal bleeding to exclude an ectopic pregnancy were evaluated. A comparison was made of the presenting signs and symptoms between patients with and without a previous history of an ectopic pregnancy. RESULTS: Of patients presenting to exclude an ectopic pregnancy, 105 had a history of an ectopic pregnancy, and 1,355 had no such history. Fifty patients were excluded because they were lost to follow-up or transferred their care to another hospital. Those with a history of an ectopic pregnancy were more likely to be diagnosed again with an ectopic pregnancy, were older and were more likely to have a history of pelvic inflammatory disease and abdominal surgery. Patients with a history of an ectopic pregnancy presented earlier with a lower hCG level. CONCLUSION: Women with a previous history of an ectopic present in a clinically different manner than do those without such a history. 相似文献
993.
994.
995.
Kellner K Lang K Papadimitriou A Leser U Milz S Schulz MB Blunk T Göpferich A 《Tissue engineering》2002,8(4):561-572
The effects of three derivatives of the N-terminal signaling domain of hedgehog proteins on cartilage engineered in vitro were investigated, with specific focus on the ability to increase tissue growth rate and concentrations of major extracellular matrix components, that is, glycosaminoglycans (GAG) and collagen, and on the effects on morphological appearance of the tissue. Bovine articular chondrocytes were cultured on biodegradable polyglycolic acid (PGA) scaffolds with or without the addition of dipalmitoylated sonic hedgehog (dp-shh), dipalmitoylated indian hedgehog (dp-ihh), or sonic hedgehog dimer (shh-dimer) to medium with either 1% or 10% fetal bovine serum (FBS). All three hedgehog proteins dose-dependently increased construct weights (by up to 1.95-fold, dp-shh at 1,000 ng/mL) and the fraction of GAG over 4 weeks (by up to 2.7-fold, dp-shh at 1,000 ng/mL), as compared to control constructs. Dp-shh and dp-ihh elicited similar responses; a 10-fold higher concentration of nonacylated shh-dimer was necessary to reach comparable results. Positive hedgehog effects were more pronounced in medium containing 1% FBS than in medium containing 10% FBS; however, at either FBS concentration, cartilaginous tissues grown in the presence of hedgehog proteins appeared morphologically more mature. Hedgehog derivatives thus appear as promising candidates to improve the development and composition of engineered cartilage. 相似文献
996.
Pfiz S Zimmermann J Hilt W 《Genes to cells : devoted to molecular & cellular mechanisms》2002,7(10):1033-1042
BACKGROUND: Slk19 is a coiled-coil protein, which locates to the kinetochores of S. cerevisiae. Most cells lacking Slk19 undergo incomplete meiosis and form dyads during sporulation. Endogenous chromosomes appeared to be predominantly divided in an equational manner during single-division meiosis of slk19 null mutants. RESULTS: We have monitored the segregation of artificial chromosomes (YACs) in slk19 null mutants during both single-division meiosis and complete meiosis. In contrast to the results obtained with endogenous chromosomes, YACs only rarely undergo equational segregation during single division meiosis, although high rates of aberrant segregation were detected. This accounts for the high frequency of lethal spores among dyads of slk19 delta null mutants. The fraction of slk19 delta cells that were able to form tetrads solely exhibited YAC segregation defects in meiosis II, whereas the segregation of YACs in meiosis I was normal in these cells. This result might indicate that correct chromosome division in meiosis I is a prerequisite for tetrad formation. slk19 null mutants also showed YAC instability in mitosis and reduced survival after the induction of mitotic spindle damage. CONCLUSION: Slk19 is required to avoid aberrant segregation of chromosomes in meiosis I and II and in mitosis. We suggest that the absence of Slk19 leads to uncoupling of chromosome movement from completion of microtubule attachment and resolution of chromosome cohesion. 相似文献
997.
Hainz U Aigner K Asch E Berger P Böhmer F Feldkircher B Horwath B Jenewein B Kassal H Kistner O Mack H Pfeiffer KP Pils K Plank J Renner D Saurwein-Teissl M Schwanzer E Trieb K Grubeck-Loebenstein B 《Wiener klinische Wochenschrift》2002,114(5-6):187-193
OBJECTIVE: The aim of the study was to evaluate, if elderly persons are sufficiently protected against infectious diseases by vaccination. PROBANDS AND METHODS: 300 elderly (> 60 years) and 300 young (< 35 years) persons from five Austrian cities were recruited according to the criteria of a field study. Antibody concentrations against tetanus, diphtheria, tickborne encephalitis and influenza were assessed by ELISA or by haemagglutination inhibition test. Disease and vaccination histories were recorded. RESULTS: The results of the study demonstrate that protection against infectious diseases was frequently insufficient in the elderly. This was partly due to the fact that old persons were not vaccinated according to recommended strategies. However, low antibody concentration and a short duration of protective humoral immunity were also observed in many elderly persons in spite of regular vaccination. This was not only the case in frail, but also in healthy elderlies. CONCLUSION: The data demonstrate that vaccination has a relatively weak and short-lasting effect in old age. The results of the study should stimulate discussions about strategies how vaccinations can be made more effective in old age. Improved campaigns, shortened vaccination intervals as well as the design of novel vaccines tailored to fulfill the specific demands of the aging immune system are imaginable. 相似文献
998.
999.
Schreiber W Herkner H Koreny M Bur A Hirschl MM Glogar D Huber K Laggner AN 《Resuscitation》2002,55(3):269-276
BACKGROUND: Several predictors of survival have been described in selected subgroups of patients suffering from acute myocardial infarction. However, data on unselected patients with acute myocardial infarction and cardiogenic shock, including patients with out-of hospital cardiac arrest, are missing. We aimed to assess predictors of survival for an unselected cohort of patients representative of clinical practice who experienced acute myocardial infarction and required continuous catecholamine support for circulatory failure. METHODS: The study was performed at a 2000 bed university hospital. All consecutive patients admitted to our emergency department with acute myocardial infarction were prospectively enrolled in a clinical trial from 1993 to 2000. DESIGN: A retrospective cohort study was performed on patients with myocardial infarction requiring catecholamine support within the first 24 h. Primary endpoint was in-hospital mortality. RESULTS: The analysis was carried out on 262 patients, 189 men (72%), median age 65 years (IQR 53-73). Out-of-hospital cardiac arrest was reported in 47% (122/262). In-hospital mortality was 53% (138/262). Survivors as compared to non-survivors exhibited significant differences with respect to age (60 vs. 68 years, P<0.0001), systolic and diastolic blood pressure on admission (110 vs. 102 mmHg, P=0.01 and 64 vs. 58 mmHg, P=0.006, respectively), initial blood serum lactate (6.8 vs. 8.3, P=0.01), peak CKMB level (93 vs. 138 U/l, P=0.005), use of adrenaline (epinephrine) (38 vs. 68%, P<0.0001) and any attempt of revascularisation (76 vs. 63%, P=0.03). In a multivariate model younger age [OR 1.06 (CI 1.03-1.10), P<0.001], no use of adrenaline [OR 2.63 (CI 1.35-5.26) P=0.005] and lower peak CKMB [OR 1.01 (CI 1.01-1.01), P<0.0001] were independently associated with in-hospital survival. CONCLUSION: In unselected patients including CPR survivors with acute myocardial infarction requiring continuous catecholamine support, younger age, the absence of continuous adrenaline administration and a lower peak CKMB were independently associated with increased in-hospital survival. 相似文献
1000.
Jan?Peter?RakeEmail author Gepke?Visser Philippe?Labrune James?V.?Leonard Kurt?Ullrich G.?Peter?A.?Smit 《European journal of pediatrics》2002,161(1):S112-S119
Life-expectancy in glycogen storage disease type I (GSD I) has improved considerably. Its relative rarity implies that no metabolic centre has experience of large series of patients and experience with long-term management and follow-up at each centre is limited. There is wide variation in methods of dietary and pharmacological treatment. Based on the data of the European Study on Glycogen Storage Disease Type I, discussions within this study group, discussions with the participants of the international SHS-symposium ‘Glycogen Storage Disease Type I and II: Recent Developments, Management and Outcome’ (Fulda, Germany; 22–25th November 2000) and on data from the literature, guidelines are presented concerning: (1) diagnosis, prenatal diagnosis and carrier detection; (2) (biomedical) targets; (3) recommendations for dietary treatment; (4) recommendations for pharmacological treatment; (5) metabolic derangement/intercurrent infections/emergency treatment/preparation elective surgery; and (6) management of complications (directly) related to metabolic disturbances and complications which may develop with ageing and their follow-up.Conclusion: In this paper guidelines for the management of GSD I are presented. 相似文献