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111.
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Serum complement levels were assayed in 26 patients with disseminated cancer, who received immunotherapy with infusion of C. parvum. Complement activation, indicated by the consumption of C3 or C4 or both, was found in 46% of the patients. Serum samples showed direct correlation between decreased C3 and conversion of C3 proactivator, whereas such conversion did not occur when C4 alone was decreased. It is concluded that the bypass (properdin) pathway was activated in patients in whom C3 consumption was detected, while the classical (C1) pathway was activated in the patients with C4 consumption unaccompanied by C3 decrease. Direct correlation was observed between delayed cutaneous hypersensitivity reactions to recall antigens and the incidence of C. parvum-associated complement activation.  相似文献   
113.
X-ray diffraction patterns from human arterial specimens containing atherosclerotic fatty streak lesions exhibited a single sharp reflection, corresponding to a structural spacing of about 35 A. Specimens without lesions did not. When specimens with fatty streaks were heated, an order-to-disorder phase transition was revealed by the disappearance of the sharp reflection. The transition was thermally reversible and its temperature varied from aorta to aorta over a range from 28 degrees to 42 degrees C. Since cholesteryl ester droplets are a major component of fatty streaks, comparison studies were made of the diffraction behavior from pure cholesteryl esters. We found that the diffraction patterns of the fatty streak material could be accounted for by the organization of the cholesteryl esters into a liquid-crystalline smectic phase that melts from the smectic to a less ordered phase upon heating. When combined with the conclusions of others from polarized light microscopy, our study shows that a droplet in the smectic phase has well-defined concentric layers of lipid molecules. In each layer, the long axes of the molecules have a net radial orientation with respect to the droplet, but the side-to-side organization is disordered. We suggest that the accessibility of portions of the lipids for specific binding to enzymes or transport proteins may be restricted when they are in the smectic state, and that exchange of lipids with surrounding membranes or other potential binding sites may likewise be inhibited. The restriction in the smectic phase should be greater than in the less ordered phases that exist at higher temperatures.  相似文献   
114.
Replacement of a long segment of esophagus for esophageal atresia or severe stenosis remains a special problem in children. The following studies were designed to test the hypothesis that a section of small bowel without serosa could survive as a free autologous transplant to replace part of the mediastinal esophagus. Laparotomy was performed in 20 adult cats, a loop of small bowel was resected and an end-to-end jejunojejunostomy was completed. The serosa of the resected bowel was removed and the mucosa-muscularis graft was used to replace a segment of the middle esophagus that was resected via a right thoracotomy. The interposed graft was entirely wrapped with adjacent skeletal muscle flaps. Postoperative studies include barium swallow and cine esophagograms, histology and blood vessel casts. Results are presented which show anatomical and functional survival of 16 grafts without blood vessel anastomoses or intrinsic vascular pedicles.  相似文献   
115.
A method for the isolation of polytene nuclei from salivary glands cells of the Diptera Rhynchosciara americana is described. The stage-specific morphological pattern of the chromosome is maintained during the isolation. The isolated nuclei show two distinct RNA polymerase activities, namely I and II, characterized on the basis of ionic requirements and alpha-amanitin sensitivity. Studies of the product under the incubation conditions show that the system allows the synthesis of high-molecular weight RNA, beside a low molecular weight peak which may comprise pre-4S and 5S RNAs. Autoradiographic studies carried out in the presence or absence of the toxin alpha-amanitin showed that micronucleoli contain products of RNA polymerase type I activity (ribosomal RNA) and that the DNA puffs are engaged in alpha-amanitin sensitive RNA synthesis and thus are sites of polymerase type II activity.  相似文献   
116.
In order to determine whether the basal hypothalamus or the pituitary (or both) is the likely locus of action of the tuberoinfundibular (TI) dopamine neurons, these regions were examined for dopamine and neuroleptic receptors. High affinity receptors for haloperidol and dopamine were found in the rat pituitary while none were detected in rat basal hypothalamus. The relative ability of two neuroleptics, chlorpromazine and haloperidol, to displace (3H)haloperidol from the receptor in monkey pituitary is similar to that for rat striatum. The lack of receptors capable of binding (3H)haloperidol or (3H)dopamine in the basal hypothalamus strongly suggests that the TI neurons do not produce postsynaptic effects in this region. The pituitary receptors for (3H)haloperidol and (3H)dopamine have the characteristics of a functional system. The presence of neuroleptic/dopamine receptors in the pituitary and lack of such receptors in the basal hypothalamus supports the hypothesis that dopamine may act directly as a prolactin release inhibiting factor (PIF) rather than releasing PIF from adjacent nerve terminals in the median eminence.  相似文献   
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118.
In the 4 studied patients presenting with an Halasz's syndrome, the disease was complicated since the neonatal period by pulmonary arterial hypertension and heart failure. Three out of the 4 infants rapidly died, one after pneumonectomy. The fourth is surviving and benefitted solely from medical cardiotonic treatment. The pathogenesis of early pulmonary arterial hypertension in Halasz's syndrome is complex. The possibly associated cardiac malformations, the persistance of fetal obstructive hypertension due to the increase of the flow in the left pulmonary artery, the left to right shunt induced by the abnormal venous return and predominantly by the systemic blood supply to the right lung, are responsible, at various degrees, for pulmonary hypertension. Among surgical procedures to be proposed, the simple ligation of abnormal arteries which take their origin from the aorta seems to be preferable to pneumonectomy.  相似文献   
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120.
The influence of 0, 50, 500 or 5,000 ppm supplemental Zn on productive characteristics, weight change, and serum and organ mineral concentrations of 60 crossbred and purebred Yorkshire gilts was evaluated. Gilts were fed their respective treatment from 30 kg body weight until the completion of two parities. Sows fed 5,000 ppm supplemental Zn weighed significantly less than sows from the other treatments when killed. Serum alkaline phosphatase activity was higher for the sows fed the highest level of Zn in all replications at 10 and 14 mo of age than for sows from the other treatments. Sows fed 0, 50 or 500 ppm had lower serum Zn and higher serum Cu concentrations than sows fed 5,000 ppm Zn at 10 and 14 mo of age. The number of pigs farrowed (total and live) and birth weight were not affected by dam's dietary treatment. However, sows receiving no additional Zn had a higher number of abnormal pigs/litter than sows on the other treatments. Sows fed 5,000 ppm additional Zn weaned fewer pigs that weighed less at weaning than sows on the other treatments. The concentration of Zn in the sow's liver increased significantly and liver Cu decreased as dietary level of Zn increased. Sows receiving 5,000 ppm Zn had lower hepatic Fe stores compared with sows receiving 500 ppm Zn. Elevated renal Cu and Zn concentrations were found in sows fed the highest level of Zn supplementation. The Zn concentration was higher and the Cu concentration lower in the aorta of sows fed 5,000 ppm Zn compared with sows fed 0 or 50 ppm additional Zn. Incidence of osteochondrosis was higher in sows supplemented with 5,000 ppm Zn than for sows from the other treatments.  相似文献   
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