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51.
BACKGROUND: Few data are available regarding pneumococcal peritonitis. We studied the clinical characteristics of intra-abdominal infections caused by Streptococcus pneumoniae and its prognosis in relation to antibiotic resistance. METHODS: We reviewed all cases of culture-proved pneumococcal peritonitis. Patients with liver cirrhosis and primary pneumococcal peritonitis were compared with patients with Escherichia coli peritonitis. RESULTS: Between January 1, 1979, and December 31, 1998, we identified 45 cases of primary pneumococcal peritonitis in patients with cirrhosis and 19 cases of secondary (or tertiary) pneumococcal peritonitis. Patients with cirrhosis and primary pneumococcal peritonitis vs those with primary E coli peritonitis had more frequent community-acquired infection, 73% vs 47%; pneumonia, 36% vs 2%; and bacteremia, 76% vs 33%; and higher attributable mortality (early mortality), 27% vs 9% (P<.05 for all). Secondary (or tertiary) pneumococcal peritonitis was associated with upper or lower gastrointestinal tract diseases; in most cases, the infection appeared after surgery. A hematogenous spread of S pneumoniae from a respiratory tract infection might be the most important origin of peritonitis; also, S pneumoniae might directly reach the gastrointestinal tract favored by endoscopic procedures or hypochlorhydria. There was an increased prevalence of penicillin and cephalosporin resistance up to 30.7% and 17.0%, respectively, although it was not associated with increased mortality rates. CONCLUSIONS: Primary pneumococcal peritonitis in patients with cirrhosis more often spread hematogenously from the respiratory tract and was associated with early mortality. In secondary (and tertiary) pneumococcal peritonitis, a transient gastrointestinal tract colonization and inoculation during surgery might be the most important mechanisms. Current levels of resistance were not associated with increased mortality rates.  相似文献   
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Somatostatin-like immunofluorescence occurs in the hypothalamus and neurohypophysis of three euryhaline teleosts: tilapia, killifish, and mudsucker. This immunofluorescence was eliminated by incubating the primary antibody with excess somatostatin or somatostatin-28 but not with urotensin II, a partial analogue of somatostatin. In all three fishes, the strongest reaction was seen in the proximal pars distalis and parts of the pars intermedia. Strongly fluorescing processes from cells of the preoptic nucleus extend toward the pituitary. Distinct fluorescence was also associated with the neurohypophysis penetrating into the rostral pars distalis in the tilapia but not in the killifish or mudsucker. In the tilapia, an extensive network of immunofluorescent fibers and small cells were present in the anterior dorsolateral telencephalon, in addition to a moderately fluorescing group of cells anterolateral to the preoptic nucleus. A small area of diffuse fluorescence was also seen in the anterior dorsolateral midbrain tegmentum. Previous physiological studies have implicated somatostatin as a regulator of prolactin cell activity in tilapia. The present study demonstrates the route by which somatostatin may be delivered to the rostral pars distalis to inhibit prolactin secretion.  相似文献   
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In order to assess the effects of free or resin-bound bile acids on colonic topography, adult rats were surgically provided with an indwelling infusion catheter in the proximal cecum, which exited at the neck behind the head. Conscious, unrestrained rats were allowed chowad libitum and were administered 1 ml of an infusion mixture twice daily for five days. The infusion mixtures included either carrier saline, 100 mg cholestyramine, 165 μmol mixed bile acids, or the bile acids bound to cholestyramine. Additional groups of rats were fed defined diets with and without 2% cholestyramine. Compared to fed controls, colonic infusions of saline had little effect on colon topography. Infusions of 100 mg of cholestyramine in saline twice each day did cause some apparent damage to surface morphology of the colon, but not to the extent observed during feeding of the resin as 2% of the diet. In contrast, extensive surface damage of the colon was observed by twice daily infusions of either 165 μmol of an equimolar mixture of cholic, deoxycholic, and chenodeoxycholic acids, or by the bile acids mixed previously with the ion-exchange resin. The data suggest that topographical damage of the colon observed during feeding of bile acid-sequestering resins is in large part due to increased concentrations of either bound or unbound bile acids in the large bowel.  相似文献   
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Haemophilus parasuis is a colonizer of healthy piglets and the etiological agent of Glässer''s disease. Differences in virulence among strains of H. parasuis have been widely observed. In order to explore the host-pathogen interaction, snatch-farrowed colostrum-deprived piglets were intranasally infected with 4 strains of H. parasuis: reference virulent strain Nagasaki, reference nonvirulent strain SW114, field strain IT29205 (from a systemic lesion and virulent in a previous challenge), and field strain F9 (from the nasal cavity of a healthy piglet). At different times after infection, two animals of each group were euthanized and alveolar macrophages were analyzed for the expression of CD163, CD172a, SLA I (swine histocompatibility leukocyte antigen I), SLA II, sialoadhesin (or CD169), and CD14. At 1 day postinfection (dpi), virulent strains induced reduced expression of CD163, SLA II, and CD172a on the surfaces of the macrophages, while nonvirulent strains induced increased expression of CD163, both compared to noninfected controls. At 2 dpi, the pattern switched into a strong expression of CD172a, CD163, and sialoadhesin by the virulent strains, which was followed by a steep increase in interleukin 8 (IL-8) and soluble CD163 in serum at 3 to 4 dpi. The early increase in surface expression of CD163 induced by nonvirulent strains went along with higher levels of IL-8 in serum than those induced by virulent strains in the first 2 days of infection. Alpha interferon (IFN-α) induction was observed only in animals infected with nonvirulent strains. Overall, these results are compatible with a delay in macrophage activation by virulent strains, which may be critical for disease production.  相似文献   
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Cervical artery dissection (CeAD) is a frequent cause of stroke among young patients. It is unclear how many CeADs occur asymptomatically or cause subtle and unspecific clinical symptoms. We hypothesize that CeAD remains often unrecognized. Accordingly, the incidence of CeAD might be higher and the stroke risk lower than generally assumed. Lack of CeAD-indicating clinical symptoms is regarded as the main cause of missed diagnoses. We further hypothesize that underrepresentation of asymptomatic and oligosymptomatic patients in CeAD studies may have biased the association between ischemia and local symptoms in CeAD patients as well as the associations of CeAD with risk factors or co-morbidities. We finally hypothesize that symptomatic CeAD may be preceded by an initial asymptomatic phase. According to this final hypothesis, the time of onset of CeAD should be considered uncertain. The issue of unrecognized CeAD is relevant, as it may affect the associations between CeAD and putative risk factors. Furthermore, the existence of clinically silent CeADs may explain why recurrent and familial CeAD have been rarely observed.  相似文献   
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Acute gastroenteritis (AGE) is a leading cause of disease worldwide. The aim of this prospective observational study is to describe the epidemiology of AGE in closed and semi-closed institutions in Catalonia. In 2017, 151 outbreaks were reported; 30.5% occurred in closed and semi-closed institutions; 71.7% caused by norovirus (NoV) (1532) cases. Person-to-person transmission accounted for 75.8% of NoV outbreaks vs 46.1% in non-NoV outbreaks (p?<?0.001). Attack rate for NoV outbreaks was 33.1% vs 14.3% for non-NoV outbreaks (RR?=?2.3; 95%CI: 2.0–2.7). The high number of affected underscores prompt and intense preventive measures to avoid the extension and perpetuation of outbreaks in these settings.

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