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61.
Summary The activity of intestinal isoenzyme of serum alkaline phosphatase was evaluated in 21 non-dialyzed patients with advanced renal failure and in 52 patients on regular hemodialysis. In patients without hepatopathy, a significant inverse correlation was found between the enzyme activity and serum calcium levels. Hepatopathy was the most significant variable influencing the enzyme activity in patients on dialysis. Secondary hyperparathyroidism and a decreased rate in enzyme elimination should be assessed for the above-normal activities of intestinal ALP in serum in chronic renal failure.  相似文献   
62.
Summary Adult rats fed 10 days a low starch-high fat diet were either adrenalectomized or sham-operated and force-fed the same diet another 5 days; 14 h before sacrifice, some animals were force-fed a sucrose diet. Activity of lactase, sucrase and maltase was increased in adrenalectomized and sham-operated rats.Supported by the National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland, USA (AM 27624).  相似文献   
63.
The domestication of cattle, sheep and goats had already taken place in the Near East by the eighth millennium bc. Although there would have been considerable economic and nutritional gains from using these animals for their milk and other products from living animals-that is, traction and wool-the first clear evidence for these appears much later, from the late fifth and fourth millennia bc. Hence, the timing and region in which milking was first practised remain unknown. Organic residues preserved in archaeological pottery have provided direct evidence for the use of milk in the fourth millennium in Britain, and in the sixth millennium in eastern Europe, based on the delta(13)C values of the major fatty acids of milk fat. Here we apply this approach to more than 2,200 pottery vessels from sites in the Near East and southeastern Europe dating from the fifth to the seventh millennia bc. We show that milk was in use by the seventh millennium; this is the earliest direct evidence to date. Milking was particularly important in northwestern Anatolia, pointing to regional differences linked with conditions more favourable to cattle compared to other regions, where sheep and goats were relatively common and milk use less important. The latter is supported by correlations between the fat type and animal bone evidence.  相似文献   
64.
Zusammenfassung Die Kathepsin D-Aktivität des kollagenolytischen Kathepsins und der Pz-Peptidase wurden während der Bildung des mittels s.c. Injektion von Terpentinol hervorgerufenen Granuloms bei Ratten verfolgt. Die Kathepsin D-Aktivität erreichte am 10. Tag ihren Höhepunkt, diejenige des kollagenolytischen Kathepsins und der Pz-Peptidase erst am 14. Tag. In dieser Phase ist die Kollagenkonzentration herabgesetzt, während sich eine ausgeprägte Resorption des Granuloms zeigt.  相似文献   
65.
We carried out whole-genome homozygosity mapping, gene expression analysis and DNA sequencing in individuals with isolated mitochondrial ATP synthase deficiency and identified disease-causing mutations in TMEM70. Complementation of the cell lines of these individuals with wild-type TMEM70 restored biogenesis and metabolic function of the enzyme complex. Our results show that TMEM70 is involved in mitochondrial ATP synthase biogenesis in higher eukaryotes.  相似文献   
66.
The terrestrial and lunar cratering rate is often assumed to have been nearly constant over the past 3 Gyr. Different lines of evidence, however, suggest that the impact flux from kilometre-sized bodies increased by at least a factor of two over the long-term average during the past approximately 100 Myr. Here we argue that this apparent surge was triggered by the catastrophic disruption of the parent body of the asteroid Baptistina, which we infer was a approximately 170-km-diameter body (carbonaceous-chondrite-like) that broke up 160(-20)+30Myr ago in the inner main asteroid belt. Fragments produced by the collision were slowly delivered by dynamical processes to orbits where they could strike the terrestrial planets. We find that this asteroid shower is the most likely source (>90 per cent probability) of the Chicxulub impactor that produced the Cretaceous/Tertiary (K/T) mass extinction event 65 Myr ago.  相似文献   
67.
Calcium (Ca2+) is an universal second messenger that regulates the most important activities of all eukaryotic cells. It is of critical importance to neurons as it participates in the transmission of the depolarizing signal and contributes to synaptic activity. Neurons have thus developed extensive and intricate Ca2+ signaling pathways to couple the Ca2+ signal to their biochemical machinery. Ca2+ influx into neurons occurs through plasma membrane receptors and voltage-dependent ion channels. The release of Ca2+ from the intracellular stores, such as the endoplasmic reticulum, by intracellular channels also contributes to the elevation of cytosolic Ca2+. Inside the cell, Ca2+ is controlled by the buffering action of cytosolic Ca2+-binding proteins and by its uptake and release by mitochondria. The uptake of Ca2+ in the mitochondrial matrix stimulates the citric acid cycle, thus enhancing ATP production and the removal of Ca2+ from the cytosol by the ATP-driven pumps in the endoplasmic reticulum and the plasma membrane. A Na+/Ca2+ exchanger in the plasma membrane also participates in the control of neuronal Ca2+. The impaired ability of neurons to maintain an adequate energy level may impact Ca2+ signaling: this occurs during aging and in neurodegenerative disease processes. The focus of this review is on neuronal Ca2+ signaling and its involvement in synaptic signaling processes, neuronal energy metabolism, and neurotransmission. The contribution of altered Ca2+ signaling in the most important neurological disorders will then be considered.  相似文献   
68.
Zusammenfassung Die Isolierung der Alkaloide Colchicin und N-Formyl-N-desacetylcolchicin ausKreysigia multiflora wird beschrieben.

The author wishes to thank Prof.A. R. Battersby, Liverpool, England, for the plant material.  相似文献   
69.
Summary The activity of intestinal isoenzyme of serum alkaline phosphatase was evaluated in 21 non-dialyzed patients with advanced renal failure and in 52 patients on regular hemodialysis. In patients without hepatopathy, a significant inverse correlation was found between the enzyme activity and serum calcium levels. Hepatopathy was the most significant variable influencing the enzyme activity in patients on dialysis. Secondary hyperparathyroidism and a decreased rate in enzyme elimination should be assessed for the above-normal activities of intestinal ALP in serum in chronic renal failure.  相似文献   
70.
Zusammenfassung Es wurden Interaktionen von Protamin mit vorher in Agar-Gel elektrophoretisch getrennten plasmatischen Eiweisskörpern untersucht. Neben der schon früher bekannten Interaktion mit Fibrinogen wurden auch solche mit beiden Klassen der plasmatischen Lipoproteine gefunden.  相似文献   
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