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1.
PURPOSE: To determine the improvement in pancreatic enhancement at helical computed tomography (CT) performed with an early delay after administration of contrast material compared with that performed with a standard delay. MATERIALS AND METHODS: Dual-phase helical CT of the abdomen was performed in 120 patients with a 150-mL bolus of contrast material infused at 5 mL/sec. Early and standard delayed scanning was performed beginning at 20 seconds and 49-71 seconds, respectively. Regions of interest were measured in the head, body, and tail of the pancreas in 92 patients. The difference in enhancement between early and standard delayed scanning was calculated. RESULTS: Mean pancreatic enhancement was 82 HU +/- 3 (standard error) with an early delay, whereas enhancement on standard delay scans was 62 HU +/- 2 (P < .001). An improvement in enhancement greater than 10 HU was attained in 66 of 92 cases (72%). CONCLUSION: Pancreatic enhancement at helical CT with an early delay after contrast material administration is often significantly greater than the enhancement seen with a standard delay when a monophasic, rapidly infused bolus of contrast material is used. 相似文献
2.
Tramadol hydrochloride is a centrally acting synthetic analgesic in widespread clinical use. Despite different degrees of opioid-like characteristics in preclinical tests, it is characterized by lack of full naloxone reversibility or naloxone-precipitated withdrawal in humans. To investigate this apparent discrepancy, the present study measured the affinity of tramadol (and its enantiomers) and an active O-desmethyl metabolite (M1) (and its enantiomers) to cloned human opioid receptors of the mu, delta and kappa type stably expressed in HN9.10 neuroblastoma cells. At mu sites, the Ki values for tramadol, its (+) and (-) enantiomers, M1, and its (+) and (-) enantiomers were 17000, 15700, 28800, 3190, 153 and 9680 nM, respectively, compared to 7.1 nM for morphine. These results are consistent with the suggestion of a non-opioid contribution to the clinical profile of tramadol. 相似文献
3.
Aged and young adults were tested by category cued recall after learning with category cues (CCR) or with item cues (ICR). CCR was about twice ICR for both aged and young adults. The aged recalled less than the young and did not benefit as much from greater encoding specificity and deeper processing in CCR. ICR and CCR were correlated, so that expected CCR can be predicted from ICR. The regression of CCR on ICR was linear for young adults, but was piecewise linear for the aged, showing that the relationship between ICR and CCR was not uniform for the aged adults. Lower than expected CCR by a subset of aged without clinical dementia may be a sign of preclinical dementia. 相似文献
4.
A patient who developed a mixed neuroendocrine carcinoma and adenocarcinoma at the site of a previous long-standing ileostomy is reported. The neuroendocrine features are documented by both ultrastructural and immunocytochemical findings. Carcinoma arising in an ileostomy site is rare but has been recorded in patients with long-standing ileostomies after colectomy for chronic inflammatory bowel disease, as in this patient. Neuroendocrine carcinoma developing in this setting apparently has not been described before, however. 相似文献
5.
Extracellular ATP has been reported to exert mitogenic and contractile effects on cultured renal mesangial cells (MCs). Since it is possible that these actions involve changes in the cAMP second messenger system, we examined the effect of extracellular nucleotides on the accumulation of cAMP in rat MCs. ATP, UTP and adenosine 5'-0-(3-thio)triphosphate (ATP gamma S) (100 microM) had no significant effects on baseline cAMP levels, but inhibited forskolin-stimulated accumulation of cAMP by 21-75% in the presence of the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX). Maximal inhibitory effects were observed at 100 microM of ATP gamma S with a threshold dose of 1 microM. ATP gamma S, ATP and UTP were the most potent inhibitors indicating stimulation of the P2u receptor. The P2x agonists adenosine 5'-(alpha, beta-methylene) triphosphate and adenosine 5'-(beta, gamma-methylene) triphosphate, and the P2y agonist 2-methylthio-ATP did not affect cAMP accumulation. Treatment with the P2 receptor antagonist suramin (200 microM) reduced the inhibition by 58%. The inhibitory effects of the nucleotides were significantly attenuated by preincubation with pertussis toxin (10-100 ng/ml). Inhibition of phospholipase C and protein kinase C did not prevent the inhibitory effect of the nucleotides. Inhibitors of forskolin-stimulated cAMP accumulation had different effects on DNA synthesis in cultured MCs as measured by 3H-thymidine uptake at 48 h: ATP, ATP gamma S and the inhibitor of adenylyl cyclase, SQ 22536, stimulated DNA synthesis in MCs, while UTP showed no significant mitogenic effect. Agents which increased baseline levels of intracellular cAMP (forskolin, IBMX, dibutyryl-cAMP) significantly diminished DNA synthesis in MCs. The results indicate that the P2u-purinergic receptor mediates inhibition of forskolin-induced cAMP accumulation which is likely due to inhibition of adenylyl cyclase. This effect appears to be partially mediated by PTX-sensitive G proteins. While the increase in cAMP accumulation is anti-mitogenic, inhibition of cAMP accumulation by P2u receptors is not correlated with MC growth control. Thus, additional mechanisms other than inhibition of cAMP accumulation by P2u receptors are likely to be involved in the mitogenesis of extracellular ATP. 相似文献
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8.
Basal cell carcinoma (BCC) is the most common type of skin cancer and the incidence of BCC is expected to rise, with increased demand on dermatology resources. Little is known of the effect on people's lives of having skin cancer. The aim of this study was to quantify the handicap caused gy basal cell carcinomas before and after therapy. Forty-four patients (22 males, mean age = 65 yrs, range = 35-81 yrs) with 48 BCCs were recruited and 37 patients completed the study. Each patient completed the UK Sickness Impact Profile (UKSIP) and the Dermatology Life Quality Index (DLQI) at the initial visit to the dermatology clinic, 1 week after treatment and 3 months after treatment. Lesions had been present for a mean of 25 months (range = 1-240 months), their mean diameter was 9.6mm (range = 3-35mm) and the sites were head and neck (79%), trunk (17%) and limbs (4%). There was no relationship between the quality of life score and size of lesion. Overall the scores at presentation were very low, rising 1 week after treatment and falling to below the initial scores at 3 months (mean UKSIP 0.4%, 0.7%, 0.13%; mean DLQI 5.3% 8.7%, 1.2%). BCCs cause little handicap. This may explain the delay in seeking medical attention and should be considered in planning public health education about BCCs. 相似文献
9.
RB Hudson 《Canadian Metallurgical Quarterly》1994,34(6):743-748
The analysis of genomic DNA fragment patterns has revealed as a powerful tool for strain discrimination in Staphylococcus aureus; for use as an epidemiological marker, stability during the course of an outbreak is an essential prerequisite. Genomic DNA fragment patterns (SmaI restriction, pulsed-field electrophoresis) of four different epidemic MRSA strains were compared along with intra- and interhospital and country-wide spread over more than 12 months in Germany. Strain I was isolated from infections in 8 hospitals. In one hospital a subclone arised which differed from the original strain by 4 fragments. Strain II was spread among 4 hospitals, isolates from three of these hospitals exhibited a variability of one to three fragments in the 150-200 kb range. Two hospitals in the Hannover-area were affected by strain III; in 17 isolates of this strain a variability up to three fragments was found in the 170-200 kb range. Strain IV was isolated from 19 cases of infections in 3 hospitals in Berlin. The fragment patterns were completely stable. When S. aureus strains are typed by genomic DNA fragment patterns, a variability in a definite range of molecular masses during the course of an epidemic should be taken into consideration. 相似文献
10.