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91.
In this study the ultrastructural aspects of egg envelope formation in the anoplocephalid cestode Mosgovoyia ctenoides are described. In the early stage of oncospheral morphogenesis, formation of three following primary embryonic envelopes takes place: (1) the capsule, (2) the outer envelope, and (3) the inner envelope. The capsule is formed from the vitellocyte material. Two macromeres contribute to the formation of the outer envelope and three mesomeres take part in the formation of the inner envelope. The three primary envelopes undergo further differentiation and transformation into the secondary envelopes, the so-called oncospheral or egg envelopes. In the advanced preoncospheral phase, the inner envelope undergoes differentiation into three sublayers: (1) a thick extra-embryophoral cytoplasmic layer; (2) an electron-dense embryophore, as a stiff pyriform apparatus; and (3) a thin intra-embryophoral cytoplasmic layer containing mesomere nuclei. The oncosphere is located in the extended cupule-like part of the pyriform apparatus. The two embryophoral horns elongate and fuse, thus forming a rigid cone. Four egg envelopes surround the mature infective oncosphere of M. ctenoides: (1) a thick capsule; (2) the outer envelope; (3) the inner envelope with a characteristic embryophore, in the form of the pyriform apparatus; and (4) the oncospheral membrane. The differentiation and ultrastructure of the egg envelopes of M. ctenoides are compared, in particular to those described in other anoplocephalids, and in general to the oncospheres of other cestode species.An erratum to this article can be found at  相似文献   
92.
It is well known that adrenaline causes leucocytosis, but the sources and the mechanisms of this have not been clarified. We investigated the contributions of subpopulations of white blood cells to this leucocytosis and the importance of the spleen, bone marrow and lymphatics in releasing leucocytes into the blood stream following an injection of adrenaline. We studied possible effects of adrenaline on blood flow to the spleen and bone marrow to see if any contribution to leucocytosis from these organs could be perfusion dependent. In intact awake rats, total blood leucocytes increased within 5 min to about 220% of baseline concentration, the increases of lymphocytes and neutrophilic granulocytes being about 250% and 160%, respectively. The T and B lymphocytes and natural killer cells were all mobilized, to about 230% to 250% of baseline concentrations. The leucocytosis was short-lasting, so that the cell concentrations returned to baseline within 25 min after adrenaline injection. The bone marrow, spleen, and efferent lymphatics all contributed substantially to this leucocytosis, since band-nucleated granulocytes increased upon adrenaline injection, and splenectomized or thoracic duct drained rats showed a markedly reduced leucocytosis in response to adrenaline. Supplementary data were obtained with bone marrow depleted (with 89Sr irradiation) rats. The release of leucocytes from these organs was apparently not blood-flow dependent in the control rats since organ perfusion remained unaltered after adrenaline injection. Adrenaline was found to stimulate the release of both mono- and polymorphonuclear cells in the awake rat and the release of leucocytes from the spleen, bone marrow and efferent lymphatics to contribute significantly to the leucocytosis.  相似文献   
93.
Objective:This study investigates the impact of physical workload factors and occupational class on working life expectancy (WLE) and working years lost (WYL) in a sample of older Finnish workers.Methods:A 70% random sample of Finns in 2004 was linked to a job exposure matrix for physical workload factors and register information on occupational class and labor market status until 2014. Transitions between being at work, time-restricted work disability, unemployment, economic inactivity, disability retirement, retirement and death were estimated. A multistate Cox regression model with transition-specific covariates was used to estimate the WLE and WYL at age 50 up to 63 years for each occupational class and physical workload factor for men and women (N=415 105).Results:At age 50, male and female manual workers had a WLE of 10.13 and 10.14 years, respectively. Among both genders, manual workers had one year shorter WLE at age 50 than upper non-manual employees. This difference was largely attributable to unemployment (men: 0.60, women: 0.66 years) and disability retirement (men: 0.28, women: 0.29 years). Self-employed persons had the highest WLE (11.08 years). Men and women exposed to four or five physical workload factors had about one year lower WLE than non-exposed workers. The difference was primarily attributable to ill-health-related reasons, including disability retirement (men: 0.45 years, women: 0.53 years) and time-restricted work disability (men: 0.23, women: 0.33 years).Conclusions:Manual workers and those exposed to physical workload factors had the lowest WLE. The differences in WYL between exposure groups can primarily be explained by ill-health-based exit routes.  相似文献   
94.
Epicondylitis is a common upper-extremity musculoskeletal disorder. It is most common at the age of 40-60 years. Epicondylitis seems to affect women more frequently than men. Diagnosis of epicondylitis is clinical and based on symptoms and findings of physical examination. The prevalence of lateral epicondylitis in the general populations is approximately 1.0-1.3% in men and 1.1-4.0% in women and that of medial epicondylitis is nearly 0.3-0.6% in men and 0.3-1.1% in women. The incidence rate of medical consultations has been estimated at 0.3-1.1 for lateral and 0.1 for medial epicondylitis per year per 100 subjects of general practice populations. Of occupational risk factors, forceful activities, high force combined with high repetition or awkward posture and awkward postures are associated with epicondylitis. The number of studies is limited to work-related psychosocial factors and the effects are not as consistent as those of physical load factors. Topical non-steroidal anti-inflammatory drugs, corticosteroid injections and acupuncture provide short-term beneficial effects. Workload modification should be considered, especially in manually strenuous jobs. According to clinical case series, surgical treatment has shown fair to good results; however, the efficacy of surgical treatment has not been evaluated in randomised controlled trials. Poorer prognosis of epicondylitis has been reported for individuals with high level of physical strain at work, non-neutral wrist postures during work activity and for those with the condition on the dominant elbow. Modification of physical factors could reduce the risk or improve the prognosis of epicondylitis.  相似文献   
95.
Chemopreventive and immunomodulatory potential of methanolic (MET) and dichloromethanic (DCl) extracts of Agaricus blazei mushroom were investigated in the postinitiation stage of colon carcinogenesis in male Wistar rats. Animals were initiated with 1,2-dimethylhydrazine (DMH) and treated i.g. with DCl or MET extracts. After 9 wk, animals were sacrificed for evaluation of aberrant crypt foci (ACF) development, crypt cellular proliferation, preneoplastic liver lesions (GST-P), proliferative response of spleen cells to mitogen, and natural killer activity. Administration of DCl extracts did not suppress DMH-induced colonic ACF nor did it affect the crypt multiplicity, but the highest dose of MET significantly reduced the development of preneoplastic lesions in the colon and liver. Lymphoproliferative response was slightly decreased in the initiated control group, which was restored by treatment with MET. No toxicity from DCl and MET extracts was observed (groups MET and DCl).  相似文献   
96.
97.
The association between carotid intima-media thickness and sciatica   总被引:1,自引:0,他引:1  
OBJECTIVE: Both clinical and epidemiologic studies have shown an association between atherosclerotic changes in the aorta or lumbar arteries and lumbar disc degeneration. However, the association between atherosclerosis and sciatica remains unknown. The aim of this study was to investigate the association between carotid intima-media thickness and sciatica. METHODS: The target population consisted of people aged 45 to 74 years, who had participated in a Finnish nationwide population study during the period 2000 to 2001 and lived within 200 km of the 6 study clinics. Of the 1867 eligible subjects, 1386 (74%) were included in the study. We used high-resolution B-mode ultrasound imaging to measure intima-media thickness, and local or radiating low back pain was determined by a standard interview and clinical signs of sciatica through a physician's clinical examination. RESULTS: Carotid intima-media thickness was associated with continuous radiating low back pain and with a positive unilateral clinical sign of sciatica among men only. After adjustment for potential confounders, each standard deviation (0.23 mm) increment in carotid intima-media thickness showed an odds ratio of 1.6 (95% confidence interval 1.1-2.3) for continuous radiating low back pain and 1.7 (95% confidence interval 1.3-2.1) for a positive unilateral clinical sign of sciatica. Carotid intima-media thickness was not associated with local low back pain. CONCLUSION: Sciatica may be a manifestation of atherosclerosis, or both conditions may share common risk factors.  相似文献   
98.

Objective

Otitis media is a multifactorial disease where genetic background may have an important role. For genome-wide association studies, it is important to understand the degree of heritability. The objective of this study was to estimate the heritability of recurrent acute otitis media and chronic otitis media with effusion.

Methods

Children operated because of recurrent or chronic otitis media at the Helsinki University Central Hospital, Finland, as well as their families were recruited during 2008-2009. A cohort of 2436 subjects was enrolled consisting of 1279 children and their parents. The study subjects answered a questionnaire concerning their otitis media history and treatment, as well as tobacco exposure, allergy and asthma history. Heritability estimates were calculated for recurrent acute, chronic and any episodes of otitis media using software especially designed for estimating heritability in family cohorts.

Results

Altogether 901 subjects suffered from recurrent otitis media and 559 from chronic otitis media with effusion. The heritability estimates in our cohort were 38.5% for recurrent (P = 7.3 × 10−9), 22.1% for chronic (P = 4.6 × 10−3) and 47.8% for any otitis media (P = 1.5 × 10−11).

Conclusions

Our results demonstrate a moderately strong and statistically significant genetic component for both recurrent acute otitis media and chronic otitis media with effusion. These results highlight the importance of unraveling the genetic factors for otitis media that are still poorly known.  相似文献   
99.
Little is known about the etiology of hepatoblastoma. Because of the young age at diagnosis, several studies have looked at various birth characteristics. The purpose of our study was to investigate the incidence of hepatoblastoma in the Nordic countries and the association between selected birth characteristics and hepatoblastoma. Data from national cancer registries and birth registries in Denmark, Sweden, Norway and Finland 1985-2006 was used. Overall, 155 children with hepatoblastoma aged 0-14 years were included and individually matched to five controls drawn randomly from national population registries. The incidence rate of hepatoblastoma was 1.7 per million person-years with a predominance of boys (1.5:1). Incidence rate was highest before the age of 1 year (8.3 per million person-years). A higher risk of hepatoblastoma was found in children with birth weight <1,500 g [odds ratio (OR) = 9.5; 95% confidence interval (CI): 2.3-38.2], born preterm in week 22-32 (OR = 4.5; CI: 1.8-11.5) and Apgar scores <7 after 1 min (OR = 3.1; CI: 1.3-7.1) and 5 min (OR = 7.5; CI: 1.8-32.4). A doubling in risk was found in children who were large for gestational age (OR = 2.3; CI: 1.0-5.3). No associations were found with birth order, maternal age or maternal smoking. Our study indicates that intrauterine and/or neonatal factors are associated with increased risk of hepatoblastoma. These may include low birth weight and asphyxia leading to neonatal intensive care. Alternatively, the factors may be a consequence of hepatoblastoma developing in utero.  相似文献   
100.
Abstract There is no consensus on treatment strategies for elderly patients with mantle cell lymphoma (MCL). In this prospective phase II study we investigated whether the poor outcome could be improved, with reasonable toxicity, by prolonging the immunochemotherapy. Ten cycles of alternating cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP)/cytarabine (AraC) with eight doses of rituximab (R) were given as induction. The potential synergism of intermediate-dose AraC and fludarabine was tested in cycles 6-8. Induction was followed by bimonthly rituximab maintenance for 2 years. The median age of the 60 included patients was 74 years, and the Mantle Cell Lymphoma International Prognostic Index (MIPI) was intermediate or high risk in 98% of the patients. The overall response rate was 95% (complete response/complete response unconfirmed 87%). The response of 11 patients improved with cycles 6-8 (R-fludarabine-AraC). Progression-free survival was 70% and overall survival 72% at 4 years, respectively. Treatment related mortality was 2%. Severe infections were rare, with only one grade 4 infection. More dose reductions were needed during fludarabine-containing courses as compared to R-AraC. In 20 patients a transient grade 4 neutropenia without severe infections was recorded during maintenance. In conclusion, elderly patients with MCL can be treated relatively intensively with acceptable toxicity.  相似文献   
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