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101.
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The nocturnal serum of 13 nongrowth hormone deficient, hyposomatomedinemic short children and of 12 normal children of average height was analyzed by both polyclonal and biclonal radioimmunoassays. The biclonal/polyclonal ratio for immunochemical grade human growth hormone was 1.0, but for the nocturnal sera in both groups, this ratio was significantly less than 1.0 (range 0.5-1.2, average 0.7-0.8). The ratio did not differ significantly between the two groups of children.  相似文献   
104.
The diagnosis of necrotizing enterocolitis (NEC) in neonates may be made by clinical presentation, roentgenographic findings, or a combination of both. Diagnosis leads to immediate treatment including nasogastric suction, parenteral antibiotics, plasma, and close monitoring of clinical, roentgenographic, and laboratory findings. Occasionally, neither the clinical nor plain roentgenographic appearance of an infant allows the diagnosis of NEC to be made or excluded with confidence. In such infants portable isotonic metrizamide gastrointestinal (GI) series were used to help make the decision of whether to begin treatment for NEC or to continue feeding the patient. Of 15 patients examined, two exhibited signs of NEC and were successfully treated medically without GI (tract) sequelae. Twelve neonates had normal results of metrizamide GI series and ten were immediately fed with no GI complication. One of these 12 infants had feedings withheld for several days as a result of a positive blood culture. One infant with severe cardiac and pulmonary disease had profound adynamic ileus and could not be fed. We have found the metrizamide GI series to be a useful study in neonates suspected of having NEC.  相似文献   
105.
The short child with subnormal plasma somatomedin C   总被引:1,自引:0,他引:1  
In 59 male and 59 female healthy children of average stature between 7 and 10 yr old, the normal range of plasma somatomedin C was investigated. The 95% tolerance limits narrowed progressively when the child's plasma somatomedin C status was described by the mean of one, two, three, or four determinations at 6-wk intervals. The 95% tolerance limits were therefore based on the mean of four determinations. In 97 children, age 7 to 10, below the 3.0 percentile in height, 44 had an average plasma somatomedin C below the 2.5 percentile. Among these hyposomatomedinemic short children, 19 were partially or totally deficient in growth hormone, 20 had normal immunoreactive growth hormone responses to dopa, glucagon, and sleep (nongrowth hormone deficient), and five had borderline provocative tests. Both growth hormone deficient and nongrowth hormone deficient children showed significant linear growth responses to 6-month courses of human growth hormone (0.16 to 0.70 unit/kg/wk). The responses of the latter group were 50 to 90% as great as those of the former.  相似文献   
106.
Haemangiopericytoma of the nose and paranasal sinuses   总被引:1,自引:0,他引:1  
The uncertain course and rarity of haemangiopericytoma in the nose and paranasal sinuses has interested both pathologists and clinicians. This tumour arises from proliferation of pericytes which invest capillary endothelium. A benign course is more common in the nose and paranasal sinuses. The first nasal haemangiopericytoma was reported by Stout in 1949. Since then only twenty cases have been reported in the literature. We present three further cases.  相似文献   
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A case of posterior fossa hemangioblastoma simulating arachnoid cyst on imaging and peroperatively is presented. In vivo proton MR spectroscopy showed evidence of large lactate and resonance at 2.37 ppm not observed earlier in the cystic lesions, including arachnoid cyst. The demonstration of this resonance may help in characterization of these lesions that may be confused with arachnoid cysts on imaging and during surgery. Electronic Publication  相似文献   
109.
To increase the local concentration of tamoxifen in estrogen receptor (ER) positive breast cancer, we have developed and characterized nanoparticle formulation using poly(epsilon -caprolactone) (PCL). The nanoparticles were prepared by solvent displacement method using acetone-water system. Particle size analysis, scanning electron microscopy, zeta potential measurements, and differential scanning calorimetry (DSC) were used for nanoparticle characterization. Biodegradation studies were performed in the presence and absence of Pseudomonas lipase in phosphate-buffered saline (PBS, pH 7.4) at 37 degrees C. Tamoxifen loading over different concentrations was analyzed by high-performance liquid chromatography (HPLC) and the optimum loading concentration was determined. In vitro release studies were performed in 0.5% (w/v) sodium lauryl sulfate (SLS) containing PBS at 37 degrees C. Cellular uptake and distribution of fluorescent-labeled nanoparticles was examined in MCF-7 breast cancer cells. SEM micrographs and Coulter analysis showed nanoparticles with spherical shape and uniform size distribution (250-300 nm), respectively. Zeta potential analysis revealed a positive surface charge of +25 mV on the tamoxifen-loaded formulation. Being hydrophobic crystalline polyester, PCL did not degrade in PBS alone, but the degradation was enhanced by the presence of lipase. The maximum tamoxifen loading efficiency was 64%. Initial burst release of tamoxifen was observed, probably due to significant surface presence of the drug on the nanoparticles. A large fraction of the administered nanoparticle dose was taken up by MCF-7 cells through non-specific endocytosis. The nanoparticles were found in the perinuclear region after 1 h. Results of the study suggest that nanoparticle formulations of selective ER modulators, like tamoxifen, would provide increased therapeutic benefit by delivering the drug in the vicinity of the ER.  相似文献   
110.
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