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101.
102.
The clinical implications of increased cytokine levels after major surgery remain unclear. In this study, systemic concentration of a spectrum of cytokines, including interleukins IL-6, IL-8, IL-10, IL-1ra, and soluble tumor necrosis factor receptor-I (sTNF-RI) was examined in patients with and without postoperative septic complications following colorectal surgery. Although there were no significant changes in IL-1, TNF-, and IL-8 serum levels during the observation period, there was a significant rise in IL-6, IL-1ra, and sTNF-RI concentrations in the entire group of patients between postoperative day 1 and 14. There were no differences between the group without and with local complications when IL-6, IL-1ra, and IL-10 were examined. The serum levels of sTNF-RI, IL-1ra, and IL-6 were found to be sensitive indicators of the pro- and anti-inflammatory response to the surgical trauma, but only sTNF-RI turned out to be a sensitive early marker of local septic postoperative complications in patients with colorectal carcinoma.  相似文献   
103.
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   
104.
The double fluorescent retrograde technique was employed to examine the distribution of the inferior olive (IO) neurones projecting to the cortex of the rostral and caudal parts of the paramedian lobule (PML) in the rabbit cerebellum, known to be the face-forelimb and hindlimb receiving areas, respectively. Moreover, this technique was also used to investigate the possibility that IO projections reaching these two somatotopically non-homologous PML regions are collaterals of the same axones. No other reports have addressed this question. After non-overlapping unilateral injections of the cytoplasmic tracer fast blue (FB) and the nuclear dye diamidino yellow (DY) into the rostral and caudal PML, respectively, numerous single FB- or DY-labelled cells were found in the defined regions of the contralateral IO. These regions showed considerable overlap, apart from the dorsal accessory olive where a clear spatial separation of labelled cell groups was observed. Furthermore, double FB + DY-labelled neurones (n = 310) were seen in the medial accessory olive, the dorsal and ventral laminas of the principal olive, in the dorsomedial cell column and the beta nucleus. It suggests that IO neurones may branch to supply the two functionally different PML regions and in this way participate in the mechanisms of forelimb-hindlimb coordination.  相似文献   
105.
Motility of unicellular organisms occurred early in evolution with the emergence of cilia and flagella. In vertebrates, motile cilia are required for numerous functions such as clearance of the airways and determination of left-right body asymmetry. Ependymal cells lining the brain ventricles also carry motile cilia, but their biological function has remained obscure. Here, we show that ependymal cilia generate a laminar flow of cerebrospinal fluid through the cerebral aqueduct, which we term as 'ependymal flow'. The axonemal dynein heavy chain gene Mdnah5 is specifically expressed in ependymal cells, and is essential for ultrastructural and functional integrity of ependymal cilia. In Mdnah5-mutant mice, lack of ependymal flow causes closure of the aqueduct and subsequent formation of triventricular hydrocephalus during early postnatal brain development. The higher incidence of aqueduct stenosis and hydrocephalus formation in patients with ciliary defects proves the relevance of this novel mechanism in humans.  相似文献   
106.
Melanin pigmentation in mammalian skin and its hormonal regulation   总被引:37,自引:0,他引:37  
Cutaneous melanin pigment plays a critical role in camouflage, mimicry, social communication, and protection against harmful effects of solar radiation. Melanogenesis is under complex regulatory control by multiple agents interacting via pathways activated by receptor-dependent and -independent mechanisms, in hormonal, auto-, para-, or intracrine fashion. Because of the multidirectional nature and heterogeneous character of the melanogenesis modifying agents, its controlling factors are not organized into simple linear sequences, but they interphase instead in a multidimensional network, with extensive functional overlapping with connections arranged both in series and in parallel. The most important positive regulator of melanogenesis is the MC1 receptor with its ligands melanocortins and ACTH, whereas among the negative regulators agouti protein stands out, determining intensity of melanogenesis and also the type of melanin synthesized. Within the context of the skin as a stress organ, melanogenic activity serves as a unique molecular sensor and transducer of noxious signals and as regulator of local homeostasis. In keeping with these multiple roles, melanogenesis is controlled by a highly structured system, active since early embryogenesis and capable of superselective functional regulation that may reach down to the cellular level represented by single melanocytes. Indeed, the significance of melanogenesis extends beyond the mere assignment of a color trait.  相似文献   
107.
The purpose of this study was to evaluate the clinical usefulness of a commercial ligase-based gene amplification method (LCxMycobacterium tuberculosis test; Abbott Laboratories, USA) for detection ofMycobacterium tuberculosis. The tuberculosis infection rate among clinical samples was 10.6%. The sensitivity, specificity, and positive and negative predictive values were 23.5%, 100%, 100%, and 91.7%, respectively, with the fluorochrome auramine stain; 32.4%, 100%, 100%, and 92.6%, respectively, with culture; and 76.5%, 95.8%, 68.4% and 97.2%, respectively, with the gene amplification method. When only samples from patients without current or previous treatment were studied, the sensitivity was 36.4% with the auramine stain, 63.6% with culture, and 100% with the gene amplification assay. The mean treatment time for culture-negative and assay-negative samples was greater than that of culture-negative and assay-positive samples. The LCxMycobacterium tuberculosis test is a sensitive method for detection and identification ofMycobacterium tuberculosis. It produces few false-positive results. However, as it can remain positive after the culture becomes negative, it is not recommended for evaluation of treatment efficiency.  相似文献   
108.
This paper reports the annual dynamics of wild rabbit fleas in a study site located in the Middle Ebro Valley, northeastern Spain. Fleas collected directly from wild rabbits included the species Spilopsyllus cuniculi (Dale), Xenopsylla cunicularis (Smit), Echidnophaga iberica (Ribeiro, Lucientes, Osácar, and Calvete), Caenopsylla laptevi (Beaucournu, Gil-Collado and Gilot), and Pulex irritans (L.). Monthly collections of adult and larval fleas made from within the first meter of selected burrow entrances also yielded fleas belonging to the same five species. Larval specimens of X. cunicularis, E. iberica, and C. laptevi were also found. Spilopsyllus cuniculi, a winter species that can only breed during the rabbit breeding season, was common on hosts from November to April. Xenopsylla cunicularis and E. iberica were summer species, whereas C. laptevi was abundant during the autumn and winter. Xenopsylla cunicularis and E. iberica larvae were found in burrows only during April and May, whereas those of C. laptevi were collected from October to January. The data suggested that X. cunicularis and E. iberica might diapause during the egg stage whereas C. laptevi diapauses during the pupal stage.  相似文献   
109.
The paper investigates the conformational stability of bovine serum albumin (BSA) and fibrinogen during 24-h incubation in turn with a linear silicone polymer (polydimethylsiloxane (PDMS)), with linear silicone oligomers (hexamethyldisiloxane and octamethyltrisiloxane) and with cyclic silicone oligomers (octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5)). Ten-fold and 100-fold excesses of siloxanes with respect to the proteins were used. Using fluorescence spectroscopy of tryptophan located in the domain of proteins and fluorescence of 8-anilino-1-naphthalenesulfonic acid (1,8-ANS), which interacts with hydrophobic domains of proteins, changes in the tertiary structure of the protein were recorded. The results demonstrated that BSA does not change its native form during 24-h incubation with siloxanes. In contrast, the tertiary structure of fibrinogen was found to be altered by both short-chain linear siloxanes: (hexamethyldisiloxane and octamethyltrisiloxane) and long-chain PDMS. The changes can be observed only at a 100-fold excess of siloxanes with respect to the protein. No conformational changes in fibrinogen exposed to cyclic siloxanes were observed.  相似文献   
110.
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