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51.
We examined the possibility of establishment of patent infections after percutaneous exposure of parasite-naive pigs to 10,000 Oesophagostomum dentatum infective larvae (L3). At 5 weeks after percutaneous exposure the pigs were slaughtered and low numbers of adult O. dentatum were recovered from the large intestine. In addition, exsheathed L3 were intravenously injected into pigs, which resulted in the recovery of fourth-stage larvae (L4) from nodules in the lungs as well as of L4 and adult worms from the large intestine. This study demonstrates the ability of porcine nodular worms to establish in the large intestine when pigs have been exposed percutaneously to infective larvae. It is possible that the larvae reach the large intestine by invading blood veins or the lymphatic system at the site of penetration. Received: 24 February 1998 / Accepted: 13 May 1998  相似文献   
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53.
Four patients with alpha-1 antitrypsin (alpha-1 AT) deficiency are presented: one woman with severe (phenotype PiZ) and 3 men with moderate (phenotype PiMZ) deficiency of alpha-1 AT. The variability of clinical presentation of hereditary emphysema is described. In all patients tobacco smoking history, spirometric and 6-minutes walking tests as well as HRCT of the lung were performed and compared. The influence of smoking on the functional status is underlined.  相似文献   
54.
Previous morphological studies revealed that the adipose tissue is innervated by adrenergic nerve fibers. Furthermore, physiological studies showed that the metabolism of adipose tissue is controlled by the adrenergic component of the nervous system. However, nothing is known on the sources of innervation of different fat tissue depots. Therefore, we decided to study the distribution of ganglionic sympathetic neurons innervating adipose tissue in the pig by means of a retrograde tracing method. We used 9 male and 9 female pigs of approximately 50 kg body weight. The retrograde tracer, Fast Blue (FB), was injected into the subcutaneous, perirenal and mesentery fat tissue depots. Results of the present study showed that numerous centers of the sympathetic nervous system innervate adipose tissue in the pig. FB+ neurons projecting to the subcutaneous fat tissue were placed in the thoraco-lumbar region of the sympathetic chain ganglia (SChG). However, neurons supplying perirenal and mesentery fat tissue depots were found in both the SChG and prevertebral ganglia (PVG). We conclude that different adipose tissue depots (subcutaneous, perirenal and mesentery) have different sources of innervation and that there is no significant difference in the distribution of neurons innervating adipose tissue in male and female pigs.  相似文献   
55.
56.
The aim of this paper is an analysis of clinical documentation and results of autopsy of 21 patients (pts) who died of invasive aspergillosis (IA) in the Institute of Tuberculosis and Chest Diseases in years 1993-2000 and the assessment of predisposing factors for IA. In 17 pts IA was the main and in other 4 only an accessory cause of death. All pts were treated with corticosteroids and/or cytostatic drugs--because of lung cancer (11 pts), cancer in other site (2 pts), haematologic disorders (2 pts), Wegener's granulomatosis (1 pt), polymyositis (1 pt), idiopathic pulmonary fibrosis (1 pt) and other diseases (3 pts). In 15 out of 21 pts granulocytopenia was revealed (from 0.008 x 10(9)/L to 0.82 x 10(9)/L) on an average one month before death. In 15 pts IA was limited to the lungs, in 6 others there were also fungal lesions in brain, kidneys, liver, spleen and heart. Pts with disseminated form of IA had significantly lower granulocyte count and were treated with higher doses of corticosteroids than others. Immunosuppressive drugs and granulocytopenia can be regarded as predisposing factors. Fatal course of IA depended also on the late diagnosis.  相似文献   
57.
From the 38th developmental stage of the tadpole of Rana esculenta the process of tongue formation consists in the fast growth of the lining of the oral cavity floor anteriorly and faucially. This process is accompanied by the development of taste organs on the dorsal side of the tongue. At developmental stages 39-42 taste disc anlages are covered by a layer of ordinary epithelial cells. At these stages, in some cells of a taste disc single synaptic-like vesicles with an electron-dense core appear. Apart from that, as early as at stage 42 differentiation of the cells of a taste disc can be observed at the ultrastructural level. It is only at the 44th stage that all cell types characteristic for the mature TD can be distinguished in TEM (i.e., taste cells, basal cells and three kinds of associate cells: mucous, wing and sustentacular). Starting from that stage changes in the cell membrane can be observed indicating the presence of afferent synaptic junctions. The antibody used in the experiment was raised against neuron-specific enolase (NSE). At each of the developmental stages investigated (38, 42, 45) nerve fibres within the connective tissue beneath the epithelium of a taste disc anlage were immunopositive for NSE. From stage 42 onwards neural elements present in the basal part of the epithelium of a taste disc anlage were also NSE-positive. Basal cells did not show immuno-reactivity for NSE at any of the developmental stages investigated.  相似文献   
58.
Wiedemann‐Rautenstrauch (neonatal progeroid) syndrome is an autosomal recessive condition with characteristic appearance of premature aging present at birth (aged face, natal teeth, and wrinkled skin). Other features of the syndrome are generalized lipoatrophy with specific fat accumulation in the lateral suprabuttock region, hypotrichosis, macrocephaly (pseudohydrocephalus), and mental retardation. We report on a new case that demonstrates all typical features of the syndrome. The girl is now 16 years and 10 months old and has had follow‐up from birth. We measured terminal restriction fragment (TRF) length to evaluate whether the patient's premature aging process is accompanied by shortening of telomere length in her cultured fibroblasts. Mean TRF of 13.5 kb found in our patient's fibroblasts is not shortened as compared to that of normal fibroblasts. Our results differ from those observed in Hutchinson‐Gilford progeria. © 2001 Wiley‐Liss, Inc.  相似文献   
59.
During the last decade increasing incidence of lung cancer among women have been observed in Poland. The aim of the study was to demonstrate differences among men and women with lung cancer. Lung cancer was diagnosed in 785 female and 4619 male in 1995 in Pulmonary Outpatients Departments. Women were younger than man when all histologic types of lung cancer were analysed (59.7 vs 61.9 years p. < 0.001). Particularly younger subjects were those with adenocarcinoma and small cell lung cancer (56.9 and 57.4 years for women and for men respectively 60.2 and 59.6 years, p < 0.001). Although squamous lung cancer was the most prevalent histological type among men (43.7%) and women (24.7%), about two times higher percentage of men had this neoplasm (p. < 0.001). Adenocarcinoma (18% vs 6.6%, p. < 0.001) and small cell lung cancer (18.5% vs 15.5% p. < 0.001) were prevalent in significantly higher percentage among female than male. Nonsmokers were more frequently noticed among women then men (20.4% vs. 1.9%, p. < 0.001), particularly those with adenocarcinoma. Also women smoked less intensively (33.6 pack/years vs. 42.3 pack/years, p < 0.001) except those with squamous cancer. The higher incidence of cancer was observed among mothers (7% vs 3.8% p. < 0.001) and fathers (7.1% vs 5.6%, p. < 0.001) of women than men with lung cancer.  相似文献   
60.
The conditions for active sensitization of hamster peritoneal and pleural mast cells and IgE-induced histamine release as well as cell desensitization were defined. Immunization of hamsters with ovalbumin (5 g) in Al/OH/3 gel (5 mg) with several boosters resulted in sensitization of peritoneal and pleural mast cells; in the presence of extracellular Ca++, pH of medium 7.2 and at 37°C these cells released up to 70% of histamine on the challenge with specific antigen. Partial release was observed when the cells were challenged with antigen in the absence of extracellular calcium. The rate of release is high during the first seconds of activation and is complete at 1 min. 30 min preincubation of peritoneal and pleural mast cells in calcium-free conditions (in the presence of 4 mM EDTA) resulted in complete desensitization of cells to subsequent action of antigen in potimal conditions. The present experiments demonstrate, that hamster peritoneal and pleural mast cells can be a useful model system forin vitro studies of the mechanisms of IgE-induced cell activation.  相似文献   
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