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311.
312.
Recent studies have suggested that Lp(a) is implicated in the high incidence of coronary heart disease in diabetic subjects, but data are still controversial. We therefore studied the distribution of plasma Lp(a), assayed by radial immunodiffusion, in a group of 224 diabetics and compared them to 92 non diabetic controls. Besides plasma Lp(a), TG and glucose were evaluated in 16 insulin-requiring diabetic patients before and after 10 days of normoglycaemia. The distribution of plasma Lp(a), as usually skewed to the left, was not different either between diabetic subjects and controls or between Type 1 and Type 2 diabetic subjects. No significant correlation was observed between Lp(a) and glycaemic control expressed by HbA1c. The sequence of normoglycaemia did not affect plasma Lp(a), no significant correlation between the variations of glycaemia and Lp(a) levels and the variations of triglyceridaemia and Lp(a) levels were found. Thus our group of diabetic subjects has a similar distribution of Lp(a) to controls. Lp(a) concentrations do not seem to be affected by chronic hyperglycaemia or rapid normalisation of glycaemic levels. However there is a strong need of standardization of Lp(a) assay before any definitive conclusion. As we have so far no efficient treatment for lowering Lp(a) in daily clinical practice, the energetic care of other associated vascular risk factors is needed.  相似文献   
313.
Out of 162 workers exposed to chemicals in the manufacture of construction plastics an outpatient and inpatient examination revealed gastrointestinal problems in 84.3%, vegetative nervous disorders in 62.6% of the examinees. In a random sample of 47 workers high acid production occurred in 63.3% and erosions, ulcers, cicatrices in the stomach and duodenum in 45.2% of them. No HLA genetic predisposition to duodenal ulcer was reported. Histological findings on gastroduodenal mucosa biopsies were indicative of the dystrophy in the chief and lining cells of the gastric glands, epithelium and stroma with formation of the dark cells. The authors insist on consideration of the above facts in examination and treatment of workers exposed to chemicals at construction plastics plants.  相似文献   
314.
Male CF1 mice were more susceptible to acute infections of Trypanosoma cruzi than female mice as evidenced by significantly greater maximum mean parasitemia of approximately 8.9 times 10-6 per ml in males as compared to 1.5 times 10-6 per ml in females. Mortality was also greater in males (80 to 90% as compared to 28% in females). Ovariectomy of female mice made them more susceptible than unoperated female of similar age and stock to the Brazil strain of T. cruzi as indicated by maximum mean parasitemia of 10.9 times 10-6 per ml in the former and 7.5 times 10-6 in the latter. Mortality of the ovariectomized mice was as great as 90% in some experiments while that of unoperated controls nerve exceeded 30%. Parasitemia and mortality is castrated male mice were not significantly different from unoperated male mice infected with T. cruzi.  相似文献   
315.
The expression and ligand binding characteristics of sigma-receptors in human placental syncytiotrophoblast and choriocarcinoma cells were investigated using haloperidol as a ligand. Haloperidol bound to purified placental brush border membranes with high affinity; the apparent dissociation constant for the process was about 3 nM. These binding sites were not related to dopamine (D2) and serotonin (5-HT2) receptors nor to serotonin and norepinephrine transporters. The ligands of sigma-receptors [3.g. (+)-3-(3-hydroxyphenyl)N-(1-propyl)piperidine, 1,3-di-(2-tolyl)guanidine, clorgyline, rimcazole, and dexromethorphan] were very potent in competing with haloperidol for the binding sites. The binding sites were detected not only in the brush border membrane, but also in intracellular membranes. The rank order of potency of various sigma-receptor ligands to inhibit haloperidol binding indicated that placental sigma-receptors belong to the sigma 1 subtype. Cocaine and its analog RTI-55 [2 beta-carbomethoxy-3 beta-(4-iodophenyl-) tropane] inhibited the binding of haloperidol to placental membranes with appreciable potency. The steroid hormones, progesterone and testosterone, were also potent inhibitors, and the inhibition constant for progesterone was 0.3 microM, a concentration much smaller than that found in plasma during pregnancy. The inhibition was competitive. beta-Estradiol and a number of other steroids were relatively much weaker inhibitors than progesterone and testosterone. Phenytoin and neuropeptide-Y did not interact with sigma-receptors in placenta. The choriocarcinoma cell line JAR was also found to express sigma-receptors in the plasma membrane as well as in intracellular membranes. The characteristics of the receptors in this cell were qualitatively similar to those of the receptors in normal placenta, including subtype identity and interaction with cocaine and progesterone. Interestingly, however, all sigma-receptor ligands interacted with the receptors in the JAR cell with much higher affinity than with the receptors in normal placenta. It is concluded that the placental syncytiotrophoblast and choriocarcinoma cells express cocaine-sensitive sigma-receptors and that progesterone is most likely an endogenous ligand for these receptors.  相似文献   
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The authors report the data concerning the use of lymphography and thermography with the purpose of establishing the differential diagnosis in 42 patients with edema of the lower limbs of a different origin. A comparative estimation of different methods of the differential diagnosis indicated the advantages of infra-red thermography.  相似文献   
318.
Clinico-roentgenological and functional studies were carried out in 78 patients 2--12 years following segmental (42 patients) and lobar (3) pneumonectomies for tuberculosis. An analysis of the data obtained indicated that partial pneumonectomies within the boundaries of 1-5 segments per se fail to produce significant disorders in the ventilatory and gas metabolism function of the lung. 2-12 years after the operation the patients show considerable ventilatory reserves. Significant respiratory disorders are observed only in patients with postoperative complications and pathological changes in the lung, pleura and bronchi conditioned by tuberculosis and non-specific lung pathology.  相似文献   
319.
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