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21.
Psychological factors were hypothesized to influence mortality, in particular, early versus later mortality. To explore the relationship between temperament, a psychological factor, and mortality in a prospective study of 1337 medical students, we constructed a measure portraying three temperament types, using latent class analysis. Death occurred in 113 subjects over 25–41 years of follow-up. In univariate survival analysis, subjects tending to direct tension inward when under stress (Tension-In) had a higher risk of mortality than Tension-Out or Stable types. These associations persisted after adjustment for age, smoking, cholesterol level, and Quetelet Index. The relative risk (RR) of mortality for Tension-In was 1.56 (95% confidence interval, 1.00–2.44) compared with the Stable group. The risk was due entirely to the excess risk in persons under 55 years of age (RR, 2.59; 95% confidence interval, 1.46–4.62); the corresponding risk of death in older persons was 0.66 (0.30–1.48). Thus temperament is a significant risk factor for mortality, in particular, premature death.  相似文献   
22.
Concentrations of antiyersinia antibody isotypes IgG1, IgG2, IgG3, IgG4, IgA and IgM were measured in 33 patients with yersiniosis using a solid-phase radioimmunoassay. Sixteen patients had a complicating reactive arthritis. Throughout the observation period IgG1 and IgM antibodies both constituted approximately one-third of the total antibodies, while IgA accounted for 10%, IgG3 accounted for 1%, and IgG4 antibodies could not be detected. IgG1, IgM, and IgA antibodies (and the total titer) had reached their peak at the beginning of the observation period (ca. day 20 after the onset of symptoms). The levels then gradually decreased; the total titers averaged 40 times the background at the beginning of the observation period and 4 times the background on day 350. IgM antibodies could be detected as late as a year after the infection. The concentration of IgG2 antibodies varied greatly from patient to patient. In most patients it increased until a plateau was reached approximately 2 months after the onset of symptoms. A decline was observed later. Five arthritic but no nonarthritic patients had a pronounced IgG2 response (more than half of the IgG antibodies were IgG2 in one or several samples).  相似文献   
23.
AIMS--To classify lesions discovered at colectomy in patients with ulcerative colitis; to assess the importance of histological findings by correlating them with biochemical parameters. METHODS--Liver tissue specimens taken at colectomy from 59 patients with chronic ulcerative colitis were studied using light microscopy. The findings were compared with results of biochemical liver function tests. RESULTS--Abnormal laboratory findings were found in 12 patients with liver histology consistent with primary sclerosing cholangitis. Non-specific reactive hepatitis was observed in six patients, eight had fatty liver, and three minor non-specific parenchymal changes. Twenty nine patients had normal liver histology. The highest cholestatic serum enzyme activities were seen in two patients with sclerosing cholangitis. Cholangiography in these patients also revealed changes in the extrahepatic bile ducts. However, identical histological changes were also present in patients with only slightly abnormal or even normal liver enzyme activities. CONCLUSION--Biochemical tests of liver function do not reliably indicate the extent or severity of bile duct damage in ulcerative colitis, the assessment of which requires liver biopsy.  相似文献   
24.
This study aimed to clarify how concentrations of vitamin C in plasma relate to the serology of periodontitis. The random sample used comprised 431 men, 194 from Finland and 237 from Russia. The plasma vitamin C concentration was determined by o-phtaldialdehyde-fluorometry, and serum immunoglobulin G antibodies to Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were determined by a multiserotype enzyme-linked immunosorbent assay (ELISA). The mean plasma vitamin C concentration was higher (P < 0.001) in Finnish subjects (mean +/- standard deviation, 4.5 +/- 2.8 mg/liter) than in Russian subjects (1.4 +/- 1.8 mg/liter). Mean antibody levels to both A. actinomycetemcomitans (4.7 +/- 3.6 versus 5.2 +/- 3.1 ELISA units [P = 0.05]) and P. gingivalis (5.7 +/- 2.5 versus 7.6 +/- 2.9 ELISA units [P < 0.001]) were lower in Finnish men than in Russian men. In the combined Finnish and Russian population, the antibody levels to P. gingivalis were negatively correlated with vitamin C concentrations (r = -0.22; P < 0.001); this association remained statistically significant (P = 0.010) in a linear regression model after adjustment for confounding factors. The proportion of P. gingivalis-seropositive subjects decreased with increasing vitamin C concentrations (P for trend, <0.01), but no trend was seen among A. actinomycetemcomitans-seropositive subjects. In conclusion, P. gingivalis infection is associated with low concentrations of vitamin C in plasma, which may increase colonization of P. gingivalis or disturb the healing of the infected periodontium.  相似文献   
25.
In the study reported here, we examined blood pressure and endocrine responses in cold conditions during salt load in young healthy subjects who had previously shown increased resting blood pressure during acutely increased sodium intake. Subjects (n=53) added 121 mmol sodium into their normal diet for 1 week. If their mean arterial pressure had increased by a minimum of 5 mmHg compared to the previous measure they were selected for subsequent experiments. The subjects (n=8) were given 121 mmol supplemental sodium · day−1 for 14 days. They were then put into a wind tunnel for 15 min (temperature −15 °C, wind speed 3.5 · ms−1). Their blood pressure increased (P < 0.05) during the cold exposure, independent of the sodium intake. Their mean (SEM) plasma noradrenaline increased from 3.58 (0.62) nmol · l−1 to 5.61 (0.79) nmol · l−1 (P < 0.05) when the subjects were given a normal diet, and from 2.45 (0.57) nmol · l−1 to 5.06 (0.56) nmol · l−1 (P < 0.05) when the subjects were given an elevated sodium diet. The starting concentrations and the endpoint concentrations were statistically similar. The plasma levels of the N-terminal fragment of pro-atrial natriuretic peptide decreased during the whole-body cold exposure: with the sodium load the change was from 256.6 (25.5) nmol · l−1 to 208.0 (25.3) nmol · l−1, and with the normal diet, from 205.8 (16.4) nmol · l−1 to 175.1 (16.1) nmol · l−1. The haematocrit and red blood cell count increased (P < 0.05) with normal and elevated sodium diet in cold conditions, but haemoglobin increased (P < 0.05) only with high salt in cold conditions. To conclude, acutely increased sodium intake does not change the blood pressure response or hormonal responses to exposure to acute cold stress in healthy subjects. Accepted: 28 September 2000  相似文献   
26.
Our aim was to study the associations between maternal vitamin C and iron intake during pregnancy and the offspring’s risk of developing islet autoimmunity and type 1 diabetes. The study was a part of the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) prospective birth cohort including children genetically at risk of type 1 diabetes born between 1997–2004. The diets of 4879 mothers in late pregnancy were assessed with a validated food frequency questionnaire. The outcomes were islet autoimmunity and type 1 diabetes. Cox proportional hazards regression analysis adjusted for energy, family history of diabetes, human leukocyte antigen (HLA) genotype and sex was used for statistical analyses. Total intake of vitamin C or iron from food and supplements was not associated with the risk of islet autoimmunity (vitamin C: HR 0.91: 95% CI (0.80, 1.03), iron: 0.98 (0.87, 1.10)) or type 1 diabetes (vitamin C: 1.01 (0.87, 1.17), iron: 0.92 (0.78, 1.08)), neither was the use of vitamin C or iron supplements associated with the outcomes. In conclusion, no association was found between maternal vitamin C or iron intake during pregnancy and the risk of islet autoimmunity or type 1 diabetes in the offspring.  相似文献   
27.
Objective: The aim of the study was to determine the currently most frequent microbial findings in Bartholin's duct abscess.Methods: Computerized records of microbial findings of 249 cases of Bartholin's duct abscess were retrospectively studied.Results: In 129 cases, only 1 microbe and, in 117 cases, >1 microbe were recovered. In 3 cases, the flora was recorded as normal for the lower genital tract. Of all bacteria isolated, 252 were aerobic or facultative and 108 were anaerobic or microaerophilic. Aerobic or facultative bacteria alone caused 142 (57%) of the 249 cases, Escherichia coli being the most frequent isolate in this group. Anaerobic or microaerophilic bacteria alone caused 33 cases (13%), Bacteroides species and Prevotella species being most frequently identified. Both aerobic or facultative and anaerobic or microaerophilic bacteria were isolated in 70 cases (28%). Candida albicans alone caused 1 case of Bartholin's duct abscess. The sexually transmitted pathogens Neisseria gonorrhoeae and Chlamydia trachomatis were both involved in only 2 cases.Conclusions: Bartholin's duct abscess was mainly caused by opportunistic bacteria, and sexually transmitted pathogens were only rarely involved in its pathogenesis. Since potentially pathogenic bacterial species were also frequently isolated, the use of antibiotics to complement the surgical treatment of Bartholin's duct abscess seems advisable, especially in patients with systemic symptoms.  相似文献   
28.
The effects of 5, 10, and 20% dietary xylitol supplementations on the biomechanical properties, histological architecture, and the contents of collagen, pyridinoline, and deoxypyridinoline in long bones of rats were studied. Tibiae were used for the three-point bending test, and femurs were used for the torsion and loading test of the femoral neck. The 10 and 20% oral xylitol administrations caused a significant increase of tibial stress, femoral shear stress, and stress of the femoral neck as compared with the controls. Parallel, but not significant, effects were also seen in the 5% xylitol supplementation group. No significant differences in strain or Young's modulus of the tibiae were detected between the groups. An increased shear modulus of elasticity in femurs was detected in the 20% supplementation group as compared with the controls. The histomorphometrical data for the secondary spongiosa of the proximal tibia revealed that trabecular bone volume was significantly greater in all dietary xylitol supplementation groups as compared with the controls. The bone volume increased along with increasing xylitol content. No significant differences between the groups were detected concerning the amount of collagen per dry weight of organic matrix, the concentrations of pyridinoline or deoxypyridinoline in collagen, or the ratio of these crosslinks. This suggests no xylitol-dependent selective changes in these structures of bone collagen. In conclusion, dietary xylitol supplementation in rats improves the biomechanical properties of bone and increases the trabecular bone volume dose dependently. Received: 30 January 1997 / Accepted: 1 October 1998  相似文献   
29.
BACKGROUND AND AIMS: The pain of an abdominal aortic aneurysm (AAA) is believed to signify rupture, and emergency surgery for symptomatic AAA is a widely accepted practice to prevent rupture. To clarify the benefit of emergency surgery we evaluated the clinical course of emergency treated patients with non-ruptured AAAs. MATERIAL AND METHODS: 110 patients (90 men, mean age 69, range 49-93; 20 women, mean age 75, range 63-89) underwent emergency repair of non-ruptured AAA between 1970 and 1992 at the Department of Thoracic and Cardiovascular Surgery of Helsinki University Central Hospital (HUCH). Survival rates after surgery were analysed using product-limit-survivorship method. The survival rates after age-stratification were compared with those of patients undergone elective surgery (n=599) or emergency surgery because of ruptured AAAs (n=363) during the same period. Risk factors affecting early and late survival rates after operation were analysed by logistic regression analysis and Cox proportional hazard model. RESULTS: Thirty-day operative mortality rates were 18 % (20/110) in the emergency non-ruptured group, compared with 7 % (42/599) in the elective group and 49 % (179/363) in the ruptured group (p<0.05). Thirty day survival rate was not changed among the nonruptured emergency group from 1970 to 1992, whereas the rates of ruptured and elective groups became better during the study period. Late survival rates for 30-day postoperative survivors were clearly reduced among the non-ruptured emergency group, without difference between the emergency operated ruptured and non-ruptured groups. Coronary artery disease was decreasing significantly early and late survival rates after emergency surgery for non-ruptured AAAs (p<0.05, logistic regression and p<0.001 Cox proportional hazard). CONCLUSIONS: Early and late mortality risk is significantly higher (p<0.001) after emergency surgery for haemodynamically stable non-ruptured AAA than after elective surgery, mainly because of coronary artery disease.  相似文献   
30.
Nosocomial acquisition of Mycobacterium fortuitum led to a disseminated infection in a leukemia patient. A linkage to showerhead water was supported by molecular typing of clinical and environmental isolates. Contamination of the hospital water system with microbes that are relatively resistant to common sanitation processes poses an increased risk of infection to neutropenic patients.  相似文献   
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