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991.
The effects of parathyroid hormone (PTH) on plasma and urinary adenosine 3',5'-monophosphate (cyclic AMP) levels were studied in normal subjects. Under basal conditions normal adults have plasma concentrations of cyclic AMP ranging from 10 to 25 nmoles/liter and excrete from 1.5 to 5 mumoles of cyclic AMP per g of urinary creatinine. About one-half to two-thirds of the cyclic AMP excreted in the urine is derived from the plasma by glomerular filtration, and the remainder is produced by the kidney. Renal production of cyclic AMP is partly under the control of PTH. It can be suppressed by infusions of calcium and stimulated by infusions of the calcium chelating agent, EDTA. Infusions of PTH in doses up to 10 mU/kg per min were associated with dose-related increases both in urinary cyclic AMP and phosphate. Infusions of PTH in doses ranging from 20 to 80 mU/kg per min did not lead to any further increase in phosphaturia but did lead to further marked increases in urinary cyclic AMP. A modest increase in plasma cyclic AMP was noted when PTH was infused at 40 mU/kg per min. Anephric patients failed to show appreciable increases in plasma cyclic AMP in response to large doses of PTH but did show expected increases in response to glucagon. Surgical removal of parathyroid adenomas from nine patients with primary hyperparathyroidism was invariably followed by a decrease in urinary cyclic AMP, PTH, in large doses, and calcium infusion produced up to 2-fold increases in the other known naturally occurring cyclic nucleotide, guanosine 3',5'-monophosphate (cyclic GMP).  相似文献   
992.

Objectives

Endometrial cancer remains a leading cause of death in women and therefore the development of new therapies is essential. The present study evaluated the effects of nimesulide alone, cisplatin alone, and combination of cisplatin and nimesulide on an Ishikawa cell line with respect to cytotoxicity and induction of apoptosis in vitro.

Study design

Ishikawa cells were treated with increasing doses of nimesulide alone, cisplatin alone, and a combination of cisplatin and nimesulide. Subsequently their effects on cytotoxicity were investigated by MTT assay, while apoptosis was investigated by DAPI and JC-1 staining and caspase-3 colorimetric assays.

Results

3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that nimesulide alone and combination of cisplatin and nimesulide have growth inhibitory effect on Ishikawa cells. Nimesulide alone and the combination of cisplatin and nimesulide induced apoptosis. Apoptosis induced by nimesulide might be related to caspase-3 activation.

Conclusions

These results suggest that nimesulide treatment is as effective as cisplatin treatment in Ishikawa cells. The combination of cisplatin and nimesulide treatment is more effective than cisplatin alone in Ishikawa cells.  相似文献   
993.
994.

Background  

This study was undertaken to assess the effect of antegrade placement of internal double-J catheters for patients who underwent open pyeloplasty for ureteropelvic junction (UPJ) obstruction.  相似文献   
995.
Eponym     
Scimitar syndrome is a rare congenital anomaly, characterized by partial or complete anomalous pulmonary venous drainage of the right or left lung into the inferior vena cava. The syndrome is commonly associated with hypoplasia of the right lung, pulmonary sequestration, persisting left superior vena cava, and dextroposition of the heart. The pathogenesis of the syndrome is unclear, but it seems to originate from a basic developmental disorder of the entire lung bud early in embryogenesis. Two main forms of scimitar syndrome have been described. Signs and symptoms can start during infancy (infantile form) or beyond (childhood/adult form). The infantile form generally presents within the first 2 months of life with tachypnea, recurrent pneumonia, failure to thrive, and signs of heart failure. The diagnosis of scimitar syndrome is usually made based on the characteristic chest X-ray films and can be confirmed by angiography; however, it is now done mostly by transthoracic or transesophageal echocardiography, noninvasive computed tomography, or magnetic resonance angiography. Fetal echocardiography using three-dimensional power Doppler imaging permits prenatal diagnosis. Most frequently, patients are asymptomatic in the absence of associated abnormalities and can be followed conservatively. For patients with congestive heart failure, repeated pneumonia, or pulmonary-to-systemic blood flow ratios greater than 1.5 and pulmonary hypertension, it is important to reroute the anomalous right pulmonary veins and repair the associated cardiac defects in order to avoid progression to right ventricular failure. The triad of respiratory distress, right lung hypoplasia, and dextroposition of the heart should alert the clinician to think of scimitar syndrome.  相似文献   
996.
997.
998.
Conclusion: Platelet-rich fibrin (PRF) membrane could be used successfully in the repair of tympanic membrane perforation and wound healing.

Objectives: To evaluate the effect of platelet-rich fibrin membrane in the repair of perforated tympanic membrane.

Methods: After otoscopic examination, a 3-mm perforation was made in the posterior quadrant of both tympanic membranes of 50 adult male Sprague-Dawley rats. Venous blood was withdrawn from the rats, then centrifuged. PRF was obtained in membrane form. The membrane was placed on the right tympanic membrane perforation. The perforations on the left side were left to spontaneously heal and, thus, formed the control group. Daily examinations were made of 20 rats and the time to healing of the tympanic membrane was recorded. The remaining 30 rats were separated into five groups of six, and histopathological examination was made. Evaluation was made in respect of the presence of oedema in the lamina propria, neovascularization, fibroblastic reaction, and inflammatory cells.

Results: The healing time of the tympanic membrane perforation was determined as mean 10.3?±?2.18 days in the study group applied with PRF and 17?±?2.40 days in the control group. Higher values in respect of fibrosis and neovascularization were obtained in the study group.  相似文献   
999.
Lower limits of protein needs in prematurely born neonates have not been adequately studied, yet providing protein in amounts maximizing accretion without excess is a goal in these infants' nutritional care. We hypothesized that with the use of amino acid oxidation methodology, it would be possible to define minimum protein requirement. Our objective was to investigate protein kinetics during short-term changes in protein intake by measurement of nitrogen balance and amino acid flux and oxidation using [(15)N]glycine, [(13)C]phenylalanine, and [(13)C]leucine tracers. Protein kinetics were examined in 21 preterm infants (gestational age: 29 +/- 3 wk; birth weight: 1091 +/- 324 g) at five protein intakes (1.0, 1.5, 2.0, 2.5, and 3.0 g x kg(-1) x d(-1)) with 1 d of adaptation to the test intakes. From nitrogen balance data, a protein need of 0.74 g x kg(-1 x -1) was estimated to achieve zero balance. For all three amino acids, flux and oxidation estimates were not different across protein intakes. Whole-body protein synthesis and breakdown estimates from [(15)N]ammonia data were 14.6 +/- 3.4 and 14.4 +/- 4.1 g x kg(-1) x d(-1), respectively. Glycine flux (680 +/- 168 micromol x kg(-1) x h(-1)) was greater than leucine flux (323 +/- 115 micromol x kg(-1) x h(-1)), which was greater than phenylalanine flux (84.3 +/- 35.2 micromol x kg(-1) x h(-1)). Leucine oxidation (36.7 +/- 15.6 micromol x kg(-1) x h(-1)) was also greater than phenylalanine oxidation (6.64 +/- 4.41 micromol x kg(-1) x h(-1)). Infants in our study were able to adapt to short-term changes in protein intake with little consequence to the overall whole-body protein economy, as measured by the three test amino acids.  相似文献   
1000.
The variable appearance of the left superior intercostal vein   总被引:1,自引:0,他引:1  
Ball  JB  Jr; Proto  AV 《Radiology》1982,144(3):445
  相似文献   
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