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71.
Bengt Robertson 《Virchows Archiv : an international journal of pathology》1968,344(3):230-242
Summary Microangiographic and histological studies, including serial sectioning, were carried out on the lungs of seven autopsy cases of transposition of the great arteries associated with interventricular septum defect. In five of the cases other cardiovascular abnormalities were also present — valvular pulmonary stenosis, pulmonary and systemic venous anomalies, atrial septal defect and coarctation of the aorta. The ages of the subjects varied from four days to 11 months. Tortuosity of the intralobular pulmonary arteries was observed in three subjects. The number, size and course of the pulmobronchial arteries were normal. A few arterial bronchopulmonary anastomoses (diameter range 50–350 µ) were demonstrated in two subjects. The diameter range of the main bronchial arteries in the aorta-injected specimens was within normal limits. The number of bronchopulmonary arteries was moderately increased in two of the older subjects. The systemic-artery supply of the pulmonary parenchyma, however, was not as prominent as in infants of the same age with isolated transposition of the great arteries.
This investigation has been supported by grants from the Swedish National Association against Heart and Chest Diseases, Karolinska Institutes Reservationsanslag, Carin Tryggers fond, and Stiftelsen Therese och Johan Anderssons Minne. 相似文献
Das intrapulmonale, arterielle Gefäßmuster bei Kindern mit Transposition der großen Arterien und Ventrikelseptumdefekt
Zusammenfassung Bei 7 Obduktionsfällen mit Transposition der großen Arterien und Ventrikelseptumdefekt wurden mikroangiographische und histologische Untersuchungen (einschl. Serienschnittstudien) der Lunge durchgeführt. Bei 5 Fällen lagen auch andere kardiovaskuläre Mißbildungen vor: Pulmonalklappenstenose, Venenanomalien, Vorhofseptumdefekte und Coarctatio aortae. Das Alter der Fälle betrug 4 Tage bis 11 Monate. Abnorm gewundene intralobuläre Pulmonalarterienäste wurden bei 3 Fällen beobachtet. Pulmobronchialarterien kamen in normaler Anzahl vor und zeigten keine Abweichungen hinsichtlich Größe oder Verlauf. Eine geringere Anzahl arterieller, bronchopulmonaler Anastomosen (Lumen 50–350 µ) wurde bei 2 der untersuchten Fälle beobachtet. Das Lumen der Hauptäste der Bronchialarterien war normal. Bei 2 der älteren Fälle war die Zahl der Bronchopulmonalarterien mäßig erhöht. Die Bronchialarterien des Lungenparenchyms zeigten jedoch keine so starke Vergrößerung und reiche Verästelung wie bei gleichaltrigen Fällen mit isolierter Transposition der großen Arterien.
This investigation has been supported by grants from the Swedish National Association against Heart and Chest Diseases, Karolinska Institutes Reservationsanslag, Carin Tryggers fond, and Stiftelsen Therese och Johan Anderssons Minne. 相似文献
72.
Accumulation of surfactant protein D in human pulmonary alveolar proteinosis. 总被引:6,自引:0,他引:6
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Surfactant protein D (SP-D) is a collagenous calcium-dependent carbohydrate-binding protein that is structurally related to the serum mannose-binding proteins and pulmonary surfactant protein A. SP-D was initially characterized as a biosynthetic product of freshly isolated rat type II cells and first purified in chemical amounts from bronchoalveolar lavage of rats with silica-induced alveolar lipoproteinosis. The present studies describe the characterization of human SP-D isolated from therapeutic bronchoalveolar lavage of patients with pulmonary alveolar proteinosis. Human proteinosis SP-D was extracted from the 10,000 x g pellet of bronchoalveolar lavage with 100 mmol/L glucose or ethylenediamine tetraacetic acid, and specifically bound to and eluted from maltosyl-agarose. The protein cross-reacted with monospecific antibodies to rat SP-D by enzyme-linked immunosorbent assay and immunoblot and eluted near the position of rat SP-D on reverse-phase high performance liquid chromatography. When chromatographed on 4% agarose (A-15M) in the presence of ethylenediamine tetraacetic acid, the solubilized human proteinosis SP-D eluted near the void volume and earlier than rat SP-D dodecamers or human SP-D multimers in the lavage supernatant. Two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting of proteins in the lavage pellet with antibodies to the carbohydrate-binding domain of proteinosis human SP-D demonstrated covalently cross-linked multimers of SP-D monomers (43 kd, reduced) and multimers of trimeric components stabilized by disulfide and non-disulfide bonds. These studies describe the isolation and biochemical characterization of human SP-D and demonstrate the abnormal accumulation of this protein in the air spaces of patients with alveolar proteinosis. 相似文献
73.
Micropuncture experiments were performed on intact and remnant kidneys of male Sprague-Dawley rats before and after angiotensin converting enzyme inhibition with captopril (0.5 mg kg-1 iv). Partially nephrectomized rats were studied at 2 and 8 weeks post-surgery before the development of systemic hypertension. At 2 weeks, nephrectomized rats had a numerically higher tubular stop-flow pressure than controls (43 +/- 2 mmHg vs. 38 +/- 2 mmHg; P = 0.08) and a higher post- to pre-glomerular resistance ratio (Re/Ra) (0.40 +/- 0.03 vs. 0.31 +/- 0.03; P = 0.08). At 8 weeks, stop-flow pressure and post- to pre-glomerular resistance ratios were similar in remnant and intact kidneys. Captopril had no effect on stop-flow pressure in 2 week post-surgery nephrectomized rats or either control group, but it increased stop-flow pressure in 8 week post-surgery nephrectomized rats (40 +/- 2 to 44 +/- 2 mmHg, P = 0.04). This increase in stop-flow pressure was associated with an increase in the post- to pre-glomerular resistance ratio (0.33 +/- 0.02-0.42 +/- 0.02, P = 0.009). Stop-flow pressure was positively correlated with the post- to pre-glomerular resistance ratio in 2-week post-surgery nephrectomized rats and their respective controls when combined (r = 0.89, P = 0.0001) and 8-week post-surgery nephrectomized rats and their respective controls combined (r = 0.78, P = 0.0001). Stop-flow pressure was not significantly correlated with mean arterial pressures or welling-point pressures in these groups.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
74.
Ulf Malmqvist Anders Arner Bengt Uvelius 《Pflügers Archiv : European journal of physiology》1991,419(3-4):230-234
The lactate dehydrogenase (LDH) activity and isoform distribution of LDH were investigated in tissue samples from the rat portal vein, aorta and urinary bladder. In addition, samples were obtained from hypertrophic urinary bladder. The total LDH activity per unit smooth muscle volume was higher in the urinary bladder compared to that in portal vein and aorta. Five LDH isoforms, reflecting different combinations of the two polypeptide chains denoted H and M, could be separated by agarose gel electrophoresis. The aorta contained more of the H form compared to the portal vein and urinary bladder. This difference suggests that the aorta, which is a slow smooth muscle, is more adapted for aerobic metabolism than the faster muscles of portal vein and urinary bladder. In the hypertrophic urinary bladder a shift in LDH isoform pattern towards less of the H form was found, which correlates with a better maintenance of contraction in anoxia in this type of hypertrophic smooth muscle. 相似文献
75.
In a study of immunotherapy 41 children with seasonal rhinoconjunctivitis due to deciduous tree pollen allergy were monitored by means of symptom scoring, patient self-evaluation, conjunctival provocation tests and lymphocyte proliferation in vitro to the allergen. The lymphocyte responsiveness to birch pollen decreased significantly during the first year of immunotherapy. However, neither the lymphocyte responsiveness before treatment nor changes in lymphocyte reactivity during the immunotherapy correlated with the clinical efficacy of the therapy as evaluated by changes in symptom scores, self-evaluation or conjunctival provocation test changes in the individual patients. The results indicate the lymphocyte responsiveness to an allergen cannot be used to select patients for immunotherapy, i.e. to predict whether a patient would benefit from immunotherapy or not, or to evaluate the effects of immunotherapy after beginning the treatment. However, lymphocyte proliferation response to an allergen indicates clinical sensitivity. 相似文献
76.
Bengt Y. Nilsson 《Acta physiologica (Oxford, England)》1968,74(3):348-358
Contractions of the pilomotor muscles of individual carpal tactile sinus hairs in the cat were studied by simultaneous recording of the movement of a single hair by means of a capacitance meter, and of the electrical activity during the muscle contraction, as recorded by an external metal microelectrode. Single shock stimulation of the nerve gave rise to a twitch contraction, whereas repetitive stimulation caused summation of contractions at frequencies higher than 0.2/sec and fusion at frequencies of 1/sec or more. The electrical response consisted of a slow potential and a superimposed spike. These components were both shown to be dependent on the stimulus strength and to be facilitated on repetitive stimulation. At stimulus frequencies higher than 3/sec the spike gradually declined in amplitude and was substituted by a rhythmic oscillation at the same rate as the stimulus. Even when no spike was recorded the contraction was sustained. Comparisons are made between the electrical activity elicited in the pilomotor muscles and the junction potentials and spikes recorded in other types of smooth muscle. 相似文献
77.
BACKGROUND: Different studies have presented conflicting results concerning the effect of menopause on lipid levels. AIMS: To describe the serum lipid profile and the prevalence of hyperlipidemia in women aged 50-60 and the perceived relation to endogenous and exogenous hormones and age. METHODS: Out of a total population of 10,766 women aged 50-59 years, 6908 (64%) participated in a health assessment program, including a lipid profile evaluation. The women were grouped according to hormonal status into pre-menopausal (PM), post-menopausal without hormone replacement therapy (PM0) (HRT) and post-menopausal with hormone replacement therapy (PMT). Age groups used were 50-54, 55-59 and >60 years. RESULTS: Serum cholesterol and triglycerides increased significantly by age in PM0 (P < 0.0001) and triglycerides also in PMT (P < 0.0001). Serum high-density lipoprotein cholesterol (HDL) levels decreased significantly by age in PMT (P = 0.002) and low-density lipoprotein cholesterol (LDL) increased in PM0 (P < 0.0001) and PMT (P = 0.007). The co-prevalence of levels of cholesterol >7 and triglycerides >2 mmol/l decreased by age in PM, but increased by age in PM0 and PMT. The prevalence of high-risk lipid levels and the prevalence of coexisting additional two metabolic risk factors were higher in the PM0 compared to the PMT group. The prevalence of serum triglycerides >1.5 and serum cholesterol >5 mmol/l were increasing by age in each of the hormonal groups. CONCLUSIONS: These data suggest that loss of endogenous sex steroids contribute substantially to an increased atherogenic lipid profile. Hormone replacement therapy may partly reverse these differences. 相似文献
78.
Nodi Dehvari Ola Isacsson Bengt WinbladAngel Cedazo-Minguez Richard F. Cowburn 《Neuroscience letters》2008
Presenilin (PS1 and PS2) mutations cause early-onset familial Alzheimer's disease (AD). In addition to affecting β-amyloid precursor protein (APP) processing and Aβ generation, PSs regulate a number of signaling pathways. We previously showed that PSs regulate both phospholipase C (PLC) and protein kinase C (PKC) α and γ activities. We also reported that PS double knockout mouse embryonic fibroblasts (MEFs) have reduced levels of PKCα and enhanced levels of PKCδ. Here, we determined whether the PS modulation of PLC/PKC has consequences for extracellular regulated kinase (Erk) signaling. Erk has been suggested to be important in AD pathology by modulating APP processing and tau phosphorylation. We found that knocking out PS1 or PS2 alone resulted in increased Erk activity and that this effect could be reversed by the PKCα inhibitor Gö6976. We also found that Erk activity following either PLC or PKC stimulation was significantly lower in PS double knockout cells and that treatment with the PKC activator phorbol 12,13-dibutyrate (PdBu) down-regulated total-Erk levels in all cells except PS double knockouts. These results demonstrate that PSs regulate Erk activity through a PKCα dependent pathway and that disruption of PLC/PKC signaling in the absence of both PS1 and PS2 results in lower downstream activation of Erk. 相似文献
79.
R. Sten K. Lossius A.A. Persson J.O.G Karlsson 《Acta physiologica (Oxford, England)》2001,171(1):29-35
Mechanisms mediating endothelium‐dependent vasodilation were investigated in femoral artery rings from <2‐day‐old (newborn) and 2‐week‐old piglets. Based on previous results we hypothesized an age difference in the relative contribution of nitric oxide(NO)‐cyclic 3′,5′‐guanosine monophosphate (cGMP) and K+ channel‐activation to acetylcholine (ACh)‐induced vasodilation. Changes in vascular tone were studied in organ baths in the absence or presence of NO synthase(NOS) inhibition or K+ channel blockade and the intra‐arterial accumulation of cGMP in response to ACh was measured with radioimmunoassay (RIA). In control experiments, relaxant responses to ACh were equal in the two age groups. In the presence of the NOS‐inhibitors N G‐monomethyl‐L ‐arginine acetate (L ‐NMMA; 100 μM ) or NG‐nitro‐L ‐arginine (L ‐NOARG; 1–100 μM ), however, relaxation was significantly more reduced in femoral artery rings from 2‐week‐old than from newborn, with lower pD2 values in the older age group. Inhibition of large (BKCa) conductance calcium‐sensitive K+ channels with tetraethylammonium chloride (TEA; 1 mM ), gave a significant rightward shift in the concentration‐response curves to ACh which was of the same magnitude in both age groups. The ACh‐induced vasodilation was abolished in both age groups by high K+ (20 mM ) in combination with L ‐NOARG (100 μM ). The relative increase in cGMP levels after addition of ACh (10 nM ) was significantly larger in rings from newborn compared with 2‐week‐old piglets (12‐ vs. four‐fold). In summary, sensitivity to NOS inhibition increased with age while the effect of K+ channel blockade with TEA was the same in femoral artery rings from newborn to 2‐week‐old piglets. Lower sensitivity to NOS inhibition and a larger increase in cGMP in response to ACh could indicate a higher efficacy of the NO/cGMP pathway in this vessel in the newborn piglet. 相似文献
80.
ErjefÄlt ersson Gustafsson Korsgren Sonmark & Persson 《Clinical and experimental allergy》1998,28(8):1013-1020