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51.
To evaluate the contribution of the splanchnic area to the carbohydrate abnormalities associated with chronic uremia, the splanchnic exchange of glucose and gluconeogenic substrates was quantitated basally and after an iv glucose load in nine uremic patients with impaired glucose tolerance and seven control subjects. In the basal state, blood glucose and splanchnic glucose production were similar in the two groups. During glucose infusion (33 mumol/kg.min for 90 min), blood glucose reached significantly higher levels in the uremic patients than in controls (P less than 0.02). Plasma insulin increased slightly more in uremic patients than in controls (P less than 0.05 at 15 min). Both basal and postglucose glucagon levels were 2- to 3-fold higher in uremic patients than in normal subjects (P less than 0.05-0.02). In both groups, splanchnic glucose balance switched from net output in the basal state (-9.4 +/- 0.5 and -8.0 +/- 1.1 mumol/kg.min in normals and uremics, respectively) to net uptake with glucose infusion. However, this response was less marked in the uremic patients than in normal subjects (P less than 0.05-0.02 at 30 and 90 min). The cumulative net splanchnic glucose balance over the 90-min study period was 538 +/- 55 mumol/kg in normal subjects and 279 +/- 89 in uremic subjects (P less than 0.05). A net splanchnic lactate uptake was present in the basal state in normal (4.2 +/- 0.5 mumol/kg.min) and uremic subjects (3.4 +/- 0.5). During glucose infusion, in normal subjects splanchnic lactate exchange switched to a net output (-4.0 +/- 1.6 mumol/kg.min), whereas in the uremic group it remained as a net uptake (1.1 +/- 0.7) throughout the study period. Splanchnic gluconeogenic amino acid uptake was similar in the two groups in the basal state (1.8 +/- 0.1 mumol/kg.min and 2.2 +/- 0.2 in normal and uremic subjects, respectively). Glucose infusion caused a marked fall in amino acid uptake by liver in normal subjects, whereas no change was observed in the uremic group (0.9 +/- 0.3 and 1.9 +/- 0.2 mumol/kg.min, respectively). Splanchnic glycerol uptake was not different in the two groups in the basal state (0.75 +/- 0.2 and 1.1 +/- 0.2 mumol/kg.min) and decreased to a similar extent during glucose infusion. We conclude the following. 1) In uremic patients with glucose intolerance but normal fasting glycemia, the splanchnic metabolism of glucose and gluconeogenic substrates is normal in the postabsorptive state.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
52.
Squamous cell carcinoma of the nail bed is a relatively uncommon tumour that may be diagnosed only after considerable delay. The first case presented is a 79-year-old man with a history of discomfort and discoloration affecting the right thumbnail of 3 years duration. The second case is a 70-year-old man who presented with a recurrent, offensive discharge from beneath the left thumbnail of 40 years duration. Clinical examination of the affected digits revealed minor nail abnormalities. The presence of tumour was fully apparent only after removal of the nail plate and inspection and biopsy of the nail bed. The cases demonstrate that subungual squamous cell carcinoma may present with prolonged symptoms and a deceptively benign appearance. The importance of consideration of the possibility of malignancy, removal of the nail plate for inspection of the nail bed and appropriate biopsy is emphasized.  相似文献   
53.
AIMS: To evaluate the effect of 10 day triple treatment on H pylori eradication and associated gastritis. METHODS: Fifty patients with H pylori positive non-ulcer dyspepsia were treated for 10 days with amoxicillin, tinidazole, and bismuth salts. Histological examination of the antral mucosa was performed before (T0), six weeks (T1), and six months (T2) after treatment. The new Sydney classification of gastritis was used, using a score from 0 to 3 to grade degree of inflammation, atrophy, activity (intraepithelial or lamina propria damage) and H pylori. RESULTS: At T0 all patients had chronic active gastritis. Lymphoid follicules were present in 12 cases. At T1 33 patients were H pylori negative: the score showed a decrease of activity (from 2.5 to 0.54). The result was confirmed at T2 (mean score 0.22). Inflammation decreased from 1.8 to 1.4 at T2. Only one case of follicular gastritis was observed. In H pylori positive patients the scores did not show significant modifications. CONCLUSIONS: Ten day triple treatment is effective in eradicating H pylori in 69% of cases, causing a decrease of the total score for gastritis. Activity, defined by polymorph infiltration, was promptly reduced when H pylori was eradicated. There was a trend to a reduction in inflammation, but atrophy was irreversible.  相似文献   
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Eur J Clin Invest 2012; 42 (10): 1068-1078 ABSTRACT: Background In many countries, the introduction of generic proton pump inhibitors (PPIs) onto the pharmaceutical market increased the phenomenon of therapeutic substitution in acid-related disorders (ARDs). Aim To investigate the treatment of ARDs in an Italian primary care setting from 2005 to 2008 by verifying: (i) dynamics of PPI prescribing; (ii) predictors of PPI switching; and (iii) healthcare resource consumption costs. Methods This was a retrospective cohort study of 102 general practitioners (GPs) who managed an average of 150?000 inhabitants in Naples. Multilevel logistic regression was used to assess the potential predictors of both PPI switching and termination. Primary care costs were expressed as the cost of ARD management per PPI user year. Results The percentage of PPI users with ARD increased from 5·5% (2005) to 7·0% (2008) (P?相似文献   
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Random styrene‐ethylene copolymers have been synthesized by the hydrogenation of styrene‐butadiene copolymers. The samples were characterized by 13C NMR spectroscopy, X‐ray powder diffraction, thermal analysis, and Fourier transform IR (FTIR) spectroscopy. In the 13C NMR spectra, the resonance of the methylene carbon next to a methine bearing a phenyl group presents splitting due to its diastereotopic positions with respect to the phenyl substituents of the second and third inserted styrene units. A definitive assignment of the resonances of the SEES sequences (S = styrene, E = ethylene) was obtained by synthesis of a suitable model compound: 5,10‐diphenyl‐pentadecane. X‐ray powder diffraction and thermal analysis show that these samples are amorphous. This is probably due to the shortness of the ethylene and styrene sequences in the copolymers. DSC thermograms show a single glass transition, at a intermediate temperature, between the Tg values of polystyrene and polyethylene, depending on the styrene content in the chain. FTIR spectra indicate the presence of styrene sequences in an isotactic arrangement.

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We examined if rat myometrial cells in culture generate nitric oxide (NO) and express various isoforms of NO synthase (NOS). Myometrial cells isolated from rats on day 18 of gestation were incubated with various stimulators and inhibitors of NOS for 24 and 48 h, and NO production was evaluated by measuring nitrites in the media and NOS proteins in the cell lysates. NO was produced by myometrial cells and its production inhibited by N(G)-methyl-L-arginine (L-NMMA). This inhibition was reversed by L-arginine (3 mM). Interleukin-1beta (IL- 1beta) significantly stimulated NO production, in a dose-dependent manner. The IL-1beta-stimulated NO production was inhibited by the NOS inhibitor, L-NMMA, whose effects were reversed by L-arginine. Abundant NOS III protein was detectable in freshly isolated myometrial cells, and this was maintained in culture in the presence of fetal bovine serum (FBS; 10%). In the absence of FBS, NOS III levels decreased significantly (by 90%) within 24 h. In contrast, NOS I and NOS II proteins were undetectable in freshly isolated muscle cells and in cells cultured without IL-1beta. However, NOS II protein in these cells was induced by IL-1beta. Thus, NO is produced by myometrial cells through the NOS III isoform, and the myometrial NO may be important in maintaining uterine quiescence during pregnancy.   相似文献   
60.
This study analyses the influence of female and male patient age and human menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and live birth rates with ovulation stimulation using HMG in combination with intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI treatment cycles in 184 patients carried out at a university fertility centre were analysed in a retrospective fashion. The main outcomes measured were clinical pregnancy rates and live birth rates. Increased female partner age (> or = 35) and male partner age (> or = 40) were found to negatively influence pregnancy rates with HMG/ IUI therapy. In addition, this study demonstrated a critical threshold of HMG requirements beyond which pregnancy did not occur. No pregnancies occurred in treatment cycles requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular maturity, irrespective of patient age. In conclusion, female partner age, male partner age, and HMG requirements all significantly influence pregnancy rates with HMG/IUI therapy.   相似文献   
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