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91.
ACTH release elicited by ether inhalation or ethervenesection and measured by changes in plasma corticosterone level was studied in rats at various time intervals after placing a complete or an anterolateral cut around the medial basal hypothalamus (MBH). There was no rise in 'resting' plasma corticosterone after acceptable isolations and, in 5 out out of 6 series of experiments, the complete or long anterolateral cuts prevented the rise in plasma corticosterone normally induced by ether stress. In contrast, ethervenesection elicited a significant increment of plasma corticosterone when the basal region of the lateral retrochiasmatic area (RCAL) was not completely transected. Possible reasons why these experiments failed to confirm previous findings are discussed. These results support the hypothesis that corticoliberin-containing fibers enter the MBH from outside and that most of these fibers run through the RCAL on their way towards the neurohemal regions of the infundibulum. 相似文献
92.
Plasma and pituitary GH content, in-vitro GH release and somatostatin-like immunoreactivity (SLI) in the stalk-median eminence were studied up to 7 days after making an anterolateral cut (ALC) around the medial-basal hypothalamus. Plasma GH concentration increased within 15 min to a very high level, then fell to a high level which was unchanged for several hours. The GH concentration then steadily decreased between days 2 and 7. The SLI content in the stalk-median eminence decreased to 3.5% of the control value within 3 days. The GH content of the anterior pituitary gland was 58.8% of the control value by 1 week after the operation but the in-vitro sensitivity to somatostatin of the GH cells failed to change. Pentobarbitone injection stimulated GH release in the sham-operated controls but decreased it in the rats with an ALC. These findings suggest that transection of somatostatin-containing fibres is followed by a rapid rise and a lasting high concentration of plasma GH which slowly returns towards lower levels in parallel with a marked depletion of pituitary GH content. In rats with transected somatostatin innervation of the median eminence, sodium pentobarbitone probably decreases GH secretion by depressing the secretion of GH-releasing hormone. 相似文献
93.
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95.
Continuous activation and deactivation of integrin CD11b/CD18 during de novo expression enables rolling neutrophils to immobilize on platelets 总被引:2,自引:3,他引:2
In an in vitro flow model, unstimulated neutrophils rolled steadily over a surface coated with platelets, until superfusion of the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (fMLP) caused a dose-dependent (10(-11) to 10(-7) mol/L) transition from rolling to stationary attachment in seconds, followed more slowly by neutrophil shape change and spreading on the surface, However, at low concentrations of Ca2+ and Mg2+ (0.1 mmol/L and 0.05 mmol/L, respectively, rather than physiologic 1 mmol/L and 0.5 mmol/L), neutrophils first halted but then started to roll again and to detach from the surface over 5 to 10 minutes. At the low cation concentration, stopping was largely inhibited by antibodies to the neutrophil integrins CD18 or CD11b, but not CD11a. When neutrophils were pretreated with antibodies to CD11b or CD18 in 1 mmol/L Ca2+ 0.5 mmol/L Mg2+, stopping was not prevented but delayed. However, if antibodies were also included with the superfused fMLP, stopping was inhibited, and detachment followed. This indicates that CD11b/CD18 was newly expressed during shape change and mediated the second phase of neutrophil immobilization and spreading in a cation-dependent manner. Prestimulated neutrophils also bound to platelets and spread, but immobilization was blocked if they were perfused with antibody to CD18 or CD11b or with low Ca2+ and Mg2+. Examining the cation-dependence further, it was evident that the presence of Mg2+ was essential for integrin-mediated adhesion and that the Mg2+ concentration determined whether immobilization could be maintained or was transient. Continuous superfusion of fMLP was also essential for maintenance of stable adhesion and spreading. Thus, activation of constitutive CD11b/CD18 rapidly and reversibly converted rolling to stationary attachment, whereas maintenance of adhesion and neutrophil spreading required continual expression of additional CD11b/CD18 that was only functional at physiologic Mg2+. Continual activation and deactivation of CD11b/CD18 during de novo expression could mediate immobilization and onward migration of neutrophils in vivo, and activated platelets appear capable of supporting this process as well as endothelial cells. 相似文献
96.
Péter Z Zala J Szabó O Telegdy L Horváth Z Makara M Schuller J 《Zeitschrift für Gastroenterologie》2000,38(10):821-825
OBJECTIVES: Little is known about the fungal colonization of the esophagus. Since alcoholic liver disease (ALD) patients are prone to fungal esophagitis, we have investigated the esophageal fungal colonization of this patient group. METHODS: One hundred consecutive ALD patients were enrolled in this prospective study. 22 patients with dyspeptic symptoms acted as controls. After taking an oropharyngeal swab, patients underwent an upper gastrointestinal endoscopy and surface material was obtained from the esophagus for direct smears and culture. RESULTS: In the ALD group pseudohyphae were found in 21.5% and yeast forms in 6.4% of the direct smears. The culture was positive in 40.8% of the ALD patients, the isolated strains were: 30 C. albicans, 2 C. kefyr, 2 C. krusei, 1 C. zeylanoides and in 3 cases the species could not be identified. 41.9% of ALD patients and 13.6% of control patients (p = 0.013) had fungi in their esophagus. Significantly more ALD patients had fungal esophagitis than in the control group (19.3% vs. 0%, p = 0.021), the rate of fungal colonization was also higher, but the difference was not significant (22.5% vs. 13.6%). A significantly higher rate of fungal esophagitis and esophageal colonization was found in patients with fungi in their oropharyngeal swabs (p = 0.00001). CONCLUSIONS: Fungal colonization of the esophagus is frequent in ALD patients. Its presence might have clinical significance in the case of liver transplantation. 相似文献
97.
A subject with HbG Philadelphia-HbH disease exhibited an unusually high alpha/beta synthesis ratio; when peripheral blood was tested in vitro on several occasions, ratios of 0.63 - 0.89 were obtained after incubations of 30-120 min. HbH amounted to 5%-8% of the circulating hemoglobin. Rapid destruction of excess newly synthesized beta-globin was demonstrated in kinetic and pulse-chase experiments. After 2 min of incubation, the alpha/beta synthesis ratio was 0.48; this figure rose to 0.89 by 30 min. The zero time alpha/beta ratio was estimated to be 0.35. The degradation of beta-chains was calculated to proceed at approximately one-half the rate of beta-globin synthesis; this result was confirmed by the loss of 50% of the specific activity in beta- chains during 9 min of a chase experiment following a 10-min radioactive pulse. The results suggest that efficient proteolysis may be responsible, in some blacks, for the low levels of excess beta- globin chains in HbH disease as well as for the mildness of the clinical disorder. 相似文献
98.
M Silengo E Belligni C Molinatto G Baldassare E Biamino N Chiesa O Zuffardi S Girirajan EE Eichler GB Ferrero 《Clinical genetics》2010,77(1):28-31
Silengo M, Belligni E, Molinatto C, Baldassare G, Biamino E, Chiesa N, Zuffardi O, Girirajan S, Eichler EE, Ferrero GB. Eyebrow anomalies as a diagnostic sign of genomic disorders. Microdeletions and microduplications in the human genome, termed genomic disorders, contribute to a high proportion of human multisystemic neurodevelopmental diseases and are detected by array‐based comparative genomic hybridization (aCGH). In general, most genomic disorders are associated with craniofacial and skeletal features and behavioural abnormalities, in addition to learning disability and developmental delay (LD/DD). Specifically, recognition of a characteristic ‘acial gestalt’ has been the key to distinguish one genomic disorder from the other. Here, we report our experience concerning the relevance of abnormal eyebrow pattern as a diagnostic indicator of specific genomic disorders. 相似文献
99.
Tjitske Hielkema Elisa G Hamer Heleen A Reinders-Messelink Carel GB Maathuis Arend F Bos Tineke Dirks Lily van Doormaal Johannes Verheijden Carla Vlaskamp Eline Lindeman Mijna Hadders-Algra 《BMC pediatrics》2010,10(1):1-8
Background
Bronchiolitis is the most common reason for admission of infants to hospital in developed countries. Fluid replacement therapy is required in about 30% of children admitted with bronchiolitis. There are currently two techniques of fluid replacement therapy that are used with the same frequency-intravenous (IV) or nasogastric (NG). The evidence to determine the optimum route of hydration therapy for infants with bronchiolitis is inadequate. This randomised trial will be the first to provide good quality evidence of whether nasogastric rehydration (NGR) offers benefits over intravenous rehydration (IVR) using the clinically relevant continuous outcome measure of duration of hospital admission.Methods/Design
A prospective randomised multi-centre trial in Australia and New Zealand where children between 2 and 12 months of age with bronchiolitis, needing non oral fluid replacement, are randomised to receive either intravenous (IV) or nasogastric (NG) rehydration. 750 patients admitted to participating hospitals will be recruited, and will be followed daily during the admission and by telephone 1 week after discharge. Patients with chronic respiratory, cardiac, or neurological disease; choanal atresia; needing IV fluid resuscitation; needing an IV for other reasons, and those requiring CPAP or ventilation are excluded. The primary endpoint is duration of hospital admission. Secondary outcomes are complications, need for ICU admission, parental satisfaction, and an economic evaluation. Results will be analysed using t-test for continuous data, and chi squared for categorical data. Non parametric data will be log transformed.Discussion
This trial will define the role of NGR and IVR in bronchiolitisTrail registration
The trial is registered with the Australian and New Zealand Clinical Trials Registry - ACTRN12605000033640 相似文献100.