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1.
The lymphatic bed has been studied in 141 hepatic preparations of the man, dog and white rat. Development of obturation in the common bile duct in the man and at modelling a similar process in the animals results in essential morphological adaptive-compensatory and destructive changes in the hepatic lymphatic bed. The adaptive-compensatory reconstruction is especially well seen at initial stages of the disease. It is manifested as a total dilatation of the bed, certain reserve elements get into work, the bed capacity increases. Then certain new structural units of the bed, collateral pathways develop. When the obturational process lasts long, certain destructive changes of the hepatic lymphatic bed elements take place. The change in the relief of endotheliocytes is their most characteristic sign. With increasing age of the patients the degree of the destructive rearrangements of the hepatic lymphatic bed increases. In the experiment carried out on the animals the lymphatic outflow from the thoracic duct is determined, being an indirect index of the hepatic lymph-forming function. An essential increase of the lymph volume, several times greater than in the control, gets from the duct into the venous bed. A connection is revealed between the morphological transformations of the bed components and its drainage function. The lymphatic bed of the liver performs also an active work concerning resorption and transport of bilirubin, its content in the organ rather increases, when the common bile duct is obturated.  相似文献   
2.
Entomological Review - In 2018, all the three species of the weevil genus Otiorhynchus Germ.: O. albidus Stierlin, O. asphaltinus Germar, and O. rotundus Marseul, first recorded from St. Petersburg...  相似文献   
3.
This study aimed to examine whether lung tissue extracellular matrix (ECM) hydrogels have protective effects on radiation-induced lung injury (RILI). The cytocompatibility and histocompatibility were tested for the obtained ECM-derived hydrogel. Sprague–Dawley rats were randomly divided into three groups (n = 18): control group (control); rats receiving irradiation and intratracheal injection of normal saline (IR + NS); and rats receiving irradiation and intratracheal injection of lung ECM-derived hydrogel (IR + ECM). The wet/dry weight ratio was used to evaluate the congestion and edema of the lungs. Histopathological analysis of lung tissues was performed using hemotoxylin and eosin staining and Masson's trichrome staining. Immunohistochemical staining and western blot analyses were carried out to determine the expression of epithelial–mesenchymal transition (EMT)-related proteins in lung tissues (E-cadherin, α-smooth muscle actin [α-SMA], and vimentin). In addition, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6), hydroxyproline, malondialdehyde (MDA), and superoxide dismutase (SOD) levels were also evaluated. The ECM-derived hydrogels had good cytocompatibility and histocompatibility. ECM-derived hydrogel treatment improved lung histopathology injury and pulmonary edema. Higher expression of E-cadherin and lower expression of vimentin and α-SMA were found in the IR + ECM group compared with those in the IR + NS group. Hydroxyproline levels were reduced by ECM-derived hydrogel treatment compared with those in the IR + NS group. Obvious increases of TNF-α, IL-6, and TGF-β1 were identified following irradiation. Marked reductions in MDA content and increases in SOD were induced by ECM-derived hydrogel treatment in rats after radiation. ECM-derived hydrogels were shown to protect against RILI, potentially by reducing EMT, inflammation, and oxidative damage.  相似文献   
4.
The effects of haloperidol, an antagonist of D2 dopamine receptors, on the functioning of Ca2+, K+, and Cl? ion channels in the membrane of Chara corallina cells and on the functional properties of their cytoskeleton was studied. Haloperidol blocked Ca2+ channels of the plasmalemma. In addition to bringing about a decrease in the amplitude of the calcium current, exposure to haloperidol decelerated the activation and inactivation of calcium channels. The effect of haloperidol was reversible; after it was removed, the characteristics of calcium current were restored. Haloperidol did not affect Ca2+-activated chloride channels. Haloperidol also inhibited microfilament-dependent motion of the cytoplasm. Cytoplasmic streaming was restored after haloperidol was removed from the extracellular solution. These results suggest that the concentration of free Ca2+ ions in the cytoplasm increases in the presence of haloperidol, and that Ca2+ channels of C. corallina plasmalemma possess specific binding sites both for dopamine receptors and for their antagonists.  相似文献   
5.
Kataev  B. M.  Dudko  R. Yu. 《Entomological Review》2019,99(6):844-852
Entomological Review - Harpalus hospes Sturm, 1818 is a predominantly Eastern Mediterranean species with three parapatric subspecies connected by the populations with intermediate characteristics...  相似文献   
6.

Introduction  

Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology.  相似文献   
7.

Background

Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.

Methods

We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.

Results

We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).

Conclusions

Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users.  相似文献   
8.
9.
Transient Ca2+ and Ca2+-dependent Cl- currents of plasmatic membranes of voltage-clamped Chara corallina freshwater alga cells were studied. Our earlier described method was used for rapid (approximately 10 ms) injection of Ca2+ ions into the cell during the deactivation period of calcium channels following their activation by a positive voltage pulse (injection by "tail" Ca2+ current). This procedure allowed one to determine the amplitude of the Ca2+ component, as well as the amplitude and kinetics of the submembrane Ca2+ concentration-dependent Cl- component for the transient current. Calculations based on the cell model allowing for Ca2+ diffusion, the Ca2+-buffering properties of the cytoplasm, and the nonlinear dependency of iCl on [Ca2+]cyt, as well as the presence of chloroplasts agreed well with the experimentally observed behavior of the transient current. The slow stage of the [Ca2+]cyt relaxation to the resting level (approximately 10(-7) M), related to the functioning of Ca2+-ATPases, was shown to take approximately 10(2) s. We assume this stage to determine the duration of the refractory period after the generation of action potential.  相似文献   
10.

Background

Due partly to physicians’ unawareness, many adults with Pompe disease are diagnosed with great delay. Besides, it is not well known which factors influence the rate of disease progression, and thus disease outcome. We delineated the specific clinical features of Pompe disease in adults, and mapped out the distribution and severity of muscle weakness, and the sequence of involvement of the individual muscle groups. Furthermore, we defined the natural disease course and identified prognostic factors for disease progression.

Methods

We conducted a single-center, prospective, observational study. Muscle strength (manual muscle testing, and hand-held dynamometry), muscle function (quick motor function test), and pulmonary function (forced vital capacity in sitting and supine positions) were assessed every 3–6 months and analyzed using repeated-measures ANOVA.

Results

Between October 2004 and August 2009, 94 patients aged between 25 and 75 years were included in the study. Although skeletal muscle weakness was typically distributed in a limb-girdle pattern, many patients had unfamiliar features such as ptosis (23%), bulbar weakness (28%), and scapular winging (33%). During follow-up (average 1.6 years, range 0.5-4.2 years), skeletal muscle strength deteriorated significantly (mean declines of ?1.3% point/year for manual muscle testing and of ?2.6% points/year for hand-held dynamometry; both p<0.001). Longer disease duration (>15 years) and pulmonary involvement (forced vital capacity in sitting position <80%) at study entry predicted faster decline. On average, forced vital capacity in supine position deteriorated by 1.3% points per year (p=0.02). Decline in pulmonary function was consistent across subgroups. Ten percent of patients declined unexpectedly fast.

Conclusions

Recognizing patterns of common and less familiar characteristics in adults with Pompe disease facilitates timely diagnosis. Longer disease duration and reduced pulmonary function stand out as predictors of rapid disease progression, and aid in deciding whether to initiate enzyme replacement therapy, or when.
  相似文献   
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