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51.
Transcapillary Fluid Movements in Sympathectomized Intestine and Skin during Hemorrhagic Hypotension
Net transcapillary fluid exchange in skin tissue (paw) and small intestine was observed during a 90 min period of hemorrhagic hypotension at 50 mm Hg in the cat. Reflex fluid transfer was prevented by regional sympathectomy and α-adrenergic blockade. Early in hemorrhage, fluid absorption from the extravascular space occurred in both tissues, apparently caused by osmosis. The process was thus co-ordinated in time with a positive arterio-venous osmolar difference, in turn caused by a marked arterial hyperosmolality. Experimental arterial hyperosmolality of similar magnitude, created by i.v. infusion of hypertonic glucose in non-bled animals, led to transcapillary fluid absorption in both intestine and skin and at rates similar to those in bleeding. Regional hypotsionen per se caused no fluid absorption. Later in hemorrhage (> 30 min), plasma fluid moved into the extravascular space both in skin and intestine, apparently due to a gradual increase of capillary hydrostatic pressure. It is concluded that the arterial hyperosmolality during bleeding can cause transcapillary fluid absorption in intestinal and skin tissues, as previously shown for skeletal muscle (Järhult 1973). The hemodynamic significance of this process for plasma volume regulation in hemorrhage is, however, much greater in skeletal muscle than in intestine and skin, mainly due to the much larger total mass of the muscle tissue. 相似文献
52.
Serretti A Lorenzi C Mandelli L Cichon S Schumacher J Nöthen MM Rietschel M Tullius M Ohlraun S 《Neuroscience letters》2004,368(3):269-273
We previously reported an association of DRD4 exon 3 long alleles with delusional symptomatology, independently from psychiatric diagnoses [Am. J. Med. Genet. 105 (2001) 283; Psychiatry Res. 80 (1998) 129]. The aim of this investigation was to replicate these results in an independent sample from Germany. We studied 394 subjects, affected by bipolar disorder (n = 32), schizoaffective disorder (n = 45), and schizophrenia (n = 317). All affected subjects were evaluated using the Operational Criteria for Psychotic Illness (OPCRIT) checklist. DRD4 variants were not associated with symptomatology of major psychosis. Our present results, obtained in an independent German sample, did not confirm the association between DRD4 variants and delusional symptomatology. However it should be considered that the original sample included a much higher rate of mood disorders and this could partially explain the discrepancy. 相似文献
53.
Three males with Robertsonian translocations were found in a sample of 1115 males examined for military service. One was a 14/15 translocation, and two were 13/14 translocations. One was spontaneous and two familial. The segregation rate of the translocations did not deviate significantly from unity in the sibships where the mother was the carrier, whereas all five children had the translocation in the two sibships where the father was the carrier. There were no abortions and no aneuploid chromosome abnormalities in the progeny of carriers with D/D translocation. There were no indications of any association between the D/D translocations and physical or mental development. 相似文献
54.
Neuropsychological deficits were investigated with respect to regional distribution of cerebral atrophy as assessed by volumetric magnetic resonance imaging (MRI) in 50 patients with Alzheimer's dementia (AD; NINCDS-ADRDA criteria) and 20 healthy volunteers. When compared between groups, test performance of all investigated neuropsychological domains including declarative memory, language, praxia, psychomotor speed, as well as attention and concentration was significantly impaired. These deficits were differentially correlated with regional atrophic changes. In particular, volumes of the right amygdala-hippocampus complex correlated with declarative memory performance, whereas volumes of the left temporo-parietal regions correlated with performance in naming and praxia. Furthermore, left frontal lobe atrophy was associated with verbal fluency. Our data confirm the central role that medial temporal atrophy plays for declarative memory deficits in AD and indicate that additional changes in the parietal, temporal and frontal lobes are responsible for further neuropsychological deficits characteristic of this disorder. 相似文献
55.
Johannes Jrhult Jan Holmberg Jan Lundvall Stefan Mellander 《Acta physiologica (Oxford, England)》1976,97(4):470-475
Changes of the arterial plasma osmolality and of the glucose concentration were followed during a 30 min period of graded hemorrhagic hypotension (80, 50, and 30 mmHg) in the cat. Bleeding evoked a significant plasma hyperosmolality at all three hypotension levels and the responses were quantitatively related to the degree of hypotension. An approximate steady state increase in the arterial plasma osmolality was reached about 20 min after the start of the bleeding and it then averaged 8, 20, and 25 mOsm/kg H2O at 80, 50, and 30 mmHg, respectively. Bleeding also evoked an increase in the plasma glucose concentration, which almost entirely accounted for the observed hyperosmolality, especially at 80 and 50 mmHg. In late stages of hypotension at 30 mmHg, elevated plasma lactate and potassium concentrations contributed to the overall hyperosmolality. — Previous hemorrhagic hypotension experiments at 50 mmHg (Järhult 1975 b) have shown that hyperosmolality serves as an important regulator of the plasma and extracellular fluid volumes during bleeding. The present results indicate that such an osmolar compensatory mechanism is operating over wide ranges of hemorrhagic hypotension. 相似文献
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57.
Neuhann Florian Ginzel Sebastian Buess Michael Wolff Anna Kugler Sabine Schlanstedt Gnter Kossow Annelene Nieen Johannes Rping Stefan 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2022,65(9):853-862
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Schon in der frühen Phase der global sehr verschieden verlaufenden COVID-19-Pandemie zeigten sich Hinweise auf den Einfluss... 相似文献
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Thomas Scholzen Elmar Endl Claudia Wohlenberg Sjaak van der Sar Ian G Cowell Johannes Gerdes Prim B Singh 《The Journal of pathology》2002,196(2):135-144
The expression of the nuclear protein Ki-67 (pKi-67) is strictly correlated with cell proliferation. Because of this, anti-Ki-67 antibodies can be used as operational markers to estimate the growth fraction of human neoplasia in situ. For a variety of tumours, the assessment of pKi-67 expression has repeatedly been proven to be of prognostic value for survival and tumour recurrence, but no cellular function has yet been ascribed to the Ki-67 protein. This study shows that a C-terminal domain of pKi-67 (Kon21) is able to bind to all three members of the mammalian heterochromatin protein 1 (HP1) family in vitro and in vivo. This interaction can be manipulated in living cells, as evidenced by ectopic expression of GFP-tagged HP1 proteins in HeLa cells, which results in a dramatic relocalization of endogenous pKi-67. Taken together, the data presented in this study suggest a role for pKi-67 in the control of higher-order chromatin structure. 相似文献