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981.
982.
Nadir Y?net?i Nevin Oru? A Omer Ozütemiz Kamil Kumanlioglu Gül Yüce Yücel Batur 《Experimental and toxicologic pathology》2002,54(3):197-201
BACKGROUND: Many interrelationships exist between the thyroid gland and the gastrointestinal tract. Several past and recent studies have shown that the thyroid gland profoundly influences the structure and function of the exocrine pancreas in the rat. In the present study we investigated the effect of methimazole (METZ), an antithyroid drug, on cerulein induced acute pancreatitis (AP) in rats. METHODS: Rats were divided into 3 groups (10-12 weeks age, 200-250 g weight, n: 10). Group B was made hypothyroid with methimazole 5 mg/kg daily for 10 days and the others were untreated euthyroid groups. After 10 days, acute pancreatitis was induced with four doses of 20 microg/kg body weight of cerulein administered s.c at hourly intervals in group A and B while the control group C was given 4 doses of I ml saline. Pancreas wet weight (mg), plasma amylase activity (IU/l) and pancreatic histology were used as endpoints to quantify the severity of the AP. RESULTS: Plasma tri-iodothyronine (T3) (ng/dl) and thyroxine (T4) (microg/dl) levels were significantly reduced after METZ treatment for 10 days (p < 0.01). METZ pretreatment reduced significantly the cerulein induced increase in pancreatic weight (1,205 +/- 12 mg in METZ treated AP group versus 1,617 +/- 14 mg in AP group, p < 0.05) and the rise in amylase activity (7,078 +/- 816 IU/l in METZ treated AP group versus 8,611 +/- 830 IU/l in AP group p < 0.05). CONCLUSION: METZ reduces the severity of cerulein induced AP in rats. This effect might be through its antithyroid property. 相似文献
983.
Polyamine metabolism in transient focal ischemia of rat brain. 总被引:4,自引:0,他引:4
Polyamine metabolism was studied in rat brains subjected to 30 min transient cerebral ischemia by measuring the activity of the key enzyme ornithine decarboxylase (ODC) and levels of the polyamines putrescine, spermidine and spermine. A transient increase in ODC activity was apparent after 4 h of recirculation in the ipsilateral cortex and striatum (P less than 0.05). Putrescine levels were significantly increased in the ipsilateral striatum after 4 h of recirculation, and after 24 h of recirculation in both the ipsilateral cortex and striatum. During ischemia spermidine levels were significantly reduced in the ipsilateral hemisphere and spermine levels in the ipsilateral cortex. It is suggested that during ischemia polyamines are released from neurons into the extracellular compartment and cleared into the blood. 相似文献
984.
C Joborn J Hetta F Niklasson J Rastad L Wide H Agren G Akerstr?m S Ljunghall 《Psychoneuroendocrinology》1991,16(4):311-322
Psychiatric disturbances are common in primary hyperparathyroidism (HPT), but their pathogenesis is essentially unknown. This study deals with cerebrospinal fluid (CSF) calcium homeostasis and its connection with parathyroid hormone (PTH), blood-brain barrier (BBB) function, and central monoamine and purine metabolites in patients with primary HPT. In 22 patients with primary HPT (serum calcium 2.85 +/- 0.21 mmol/l), the CSF concentrations of total and ionized calcium were higher (1.21 +/- 0.08 mmol/l, p less than 0.01, and 1.09 +/- 0.05 mmol/l, p less than 0.001, respectively) than in 11 normocalcemic reference subjects. The values correlated with serum calcium concentration (p less than 0.001) and CSF/serum albumin ratio, a measure of BBB permeability. The latter ratio was elevated in one-third of the patients with HPT, indicating BBB damage. CSF immunoreactive intact PTH was higher in the HPT patients than in the reference group (p less than 0.05), and serum and CSF PTH were positively correlated (p less than 0.05). The CSF levels of the monoamine metabolites 5-hydroxyindoleacetic acid (5HIAA) and homovanillic acid (HVA) were lower, and the level of urate in CSF was higher, in the HPT patients than in the reference subjects, while there were no consistent differences in CSF hypoxanthine or xanthine. CSF 5HIAA correlated inversely with CSF ionized calcium (r = -0.42, p = 0.02). After parathyroid surgery, CSF calcium and urate decreased significantly and CSF monoamine metabolites increased slightly. The decrease in CSF ionized calcium correlated with the alleviation of psychiatric symptoms. The results indicate the importance of increased CSF calcium concentrations in patients with primary HPT and suggest a relation between central calcium regulation and central turnover of monoamines. 相似文献
985.
In subtypes of schizophrenia and unipolar depression, both increased and decreased levels of platelet serotonin were found. Hyperserotonemia was usually observed in patients with psychotic features (i.e., in paranoid schizophrenia and psychotic depression). Hyposerotonemia, although less common than hyperserotonemia, was present in nonparanoid schizophrenia and nonpsychotic depression (i.e., in patients without psychotic symptoms). A sex difference in platelet monoamine oxidase activity was observed among healthy subjects, but not among schizophrenic patients. The activity of platelet monoamine oxidase in paranoid and nonparanoid schizophrenic patients did not differ from that in healthy subjects. The findings in this study suggest that biological differences between subtypes of unipolar depression or schizophrenia might depend upon the presence of psychotic symptoms. 相似文献
986.
B Lindel?f 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1989,40(1):4-7
Grenz rays (ultrasoft X-rays, Bucky rays) have been used in the treatment of benign skin disorders for more than 60 years. The mechanism of action, the clinical effect and the potential carcinogenic effect have remained largely unknown, and many of the reported studies are now obsolete. Recent studies of both the clinical and the basic characteristics of grenz rays have shown that the number of Langerhans' cells decreases in the human epidermis after treatment and that grenz rays can suppress the expression of nickel allergy in sensitive individuals. Also, very good results have been reported in the treatment of psoriasis of the scalp. A large-scale study involving more than 14,000 patients has shown that grenz ray therapy cannot be excluded as a risk factor in the development of non-melanoma skin tumors, but this risk factor is small and can virtually be disregarded when certain therapy recommendations are followed. This article is an attempt to summarize the present knowledge of grenz ray therapy. 相似文献
987.
Fine arterial branches on the superior surface of corpus callosum were investigated on 22 human brains under stereomicroscope. These branches were directed toward: 1. the upper surface of corpus callosum (3-6 branches, mean 8), 2. the depths of the sulcus corporis callosi (4-13 branches, mean 7), and 3. the cingulate gyrus (1-10 branches, mean 5). All the vessels composing the pericallosal pial plexus have a uniformed caliber of 0.9-0.6 mm at their origins, and 0.7-0.3 mm after branching. In 9 cases a longitudinal vessel within the stria longitudinalis medialis, connected with the pial plexus was found. Important details of morphology of this plexus and their significance are discussed. 相似文献
988.
H F D?ring 《Zeitschrift für Hautkrankheiten》1987,62(11):894-6, 899-900
In a biometrically controlled study on psoriatic patients, we investigated the efficacy and tolerability of bifonazole 1% plus urea 20% cream. In each of our ten patients, two lesions were treated over a period of 29 to 40 days (34 days on the average). Therapeutic results were not satisfying with lesions on extremities in comparison to those on head and body. On head and trunk, the size of the lesions amounted to 11.8 and 10.3 cm2, resp., before treatment, 2.8 and 4.3 cm2, resp., after therapy. On the extremities, we only noticed a reduction in size from 15.8 cm2 before to 13.8 cm2 after treatment. In total, the therapy was considered successful in 14 of the 20 lesions. Especially those four patients who predominantly showed lesions of the sebopsoriatic type were well-improved. Thus this therapy is particularly recommended in case of sebopsoriasis. 相似文献
989.
S R Schweinberger C Buse R B Freeman P W Sch?nle W Sommer 《Journal of clinical and experimental neuropsychology》1992,14(5):839-856
To clarify whether the impairment of right-brain-damaged (RBD) patients in face recognition is related to perceptual or mnestic processing stages, we tested unilaterally lesioned patients and controls in a Sternberg-type memory search task. Subjects had to memorize sets of 1, 2, or 3 faces (or, in a control condition, digits) and were then to recognize these memorized stimuli among new ones by speeded choice reactions. In this task, deficits in stimulus encoding and memory search should show up in increased intercepts and slopes, respectively, of the RT function over memory set size. A face-specific impairment of the RBD patient group, consisting in longer reaction times and higher error rates, was confirmed but could not be unequivocally attributed to either stimulus encoding or memory search. However, inspection of individual data suggested that (1) some RBD patients are virtually unimpaired in face recognition and (2) if impairment after right hemisphere damage is present, it may selectively affect either stimulus encoding or memory search. 相似文献
990.
The bond strength of porcelain fused to cast and wrought titanium surfaces was calculated from fracture loads in a 4-point bending test. Two different porcelain were applied (O'Hara and Duceratin). The surface of Ti-cast specimens was treated in two different ways to produce variations in the impurity level before porcelain veneering. Microhardness measurements as well as scanning electron microscopy with EDX analysis were conducted. The results showed no significant difference in bond strength between the two porcelains. Nor was any difference in bond capacity found between thoroughly blasted castings and wrought titanium. Significantly lower bond strengths were observed for lightly blasted specimens and for specimens treated with Gold bonding agent. Impurities in the surface region of the castings were found to be due to contact with the investment during solidification. This indicates that a thin surface layer (50-100 microns) of the casting should be removed before firing of the porcelain. 相似文献