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1.
调查1988年3月~5月我院591例住院病例,发生96例次院内感染,总发病率16.2%。院内感染病原菌中,革蓝氏阴性杆菌占72.9%,革蓝氏阳性球菌占12.9%,念珠菌属占14.1%。院内感染病原菌的耐药性明显高于院外菌株。绿脓杆菌对庆大霉素和羧苄青霉素的耐药率分别为63.6%和54.5%。其它革蓝氏阴性杆菌院内株对常用抗生素如氨苄青霉素、羧苄青霉素、庆大霉素和妥布拉霉素的耐药率分别为82.5%、 67.5%、47.5%和45%。革蓝氏阳性球菌院内株的耐药性也很严重,表葡菌对多种半合成青霉素类、红霉素、复方新诺明甚至万古霉素的耐药率达60%以上。同时分离出耐甲氧西林金葡菌。  相似文献   
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OBJECTIVE: We compared early pulmonary (18)fluorodeoxyglucose ((18)FDG) uptake in infants who had very low birth weight with and without exposure to intrauterine inflammation by using positron emission tomography (PET). A secondary goal was to correlate (18)FDG uptake with later death or bronchopulmonary dysplasia. METHODS: Within 72 hours of birth, 22 singleton infants between 25 and 30 weeks of gestation had a thoracic PET scan after intravenous (18)FDG. Influx constants (K(i)) for (18)FDG were determined. Placental histology assessed exposure to intrauterine inflammation. RESULTS: Chorioamnionitis was found in 13 infants. Seven of these infants also had evidence of funisitis. No inflammation was detected in the remaining nine infants. Median (minimum, maximum) thoracic K(I) was 0.008 (0.006, 0.011) mL/min/mL in infants with funisitis, 0.006 (0.002, 0.008) in infants with chorioamnionitis only, and 0.006 (0.001, 0.015) in infants with no evidence of intrauterine inflammation (P=.16). No relation was found between K(i) and later death or bronchopulmonary dysplasia. Cord blood interleukin-6 was elevated in newborns with placental inflammation (P=.014). CONCLUSION: Early thoracic PET scanning for metabolically active inflammatory cells does not differ between infants with and without exposure to intrauterine inflammation. Evidence of early intrapulmonary sequestration of inflammatory cells in some infants without chorioamnionitis points to the complex etiology of postnatal inflammation.  相似文献   
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Short Time Exposure (STE) test is an easy in vitro eye irritation test that assesses cytotoxicity in SIRC cells (rabbit corneal cell line) following a 5 min dose treatment. To assess intra-laboratory reproducibility, medium control, three vehicles (saline, saline containing 5% (w/w) dimethyl sulfoxide, and mineral oil) and three standard chemicals (sodium lauryl sulfate, calcium thioglycolate, and Tween 80) were evaluated. Assessments were repeated 30 times for vehicles and 18 times for standard chemicals; resulting in almost the same cell viability and a low coefficient of variation value. In addition, the STE eye irritation rankings of three standard chemicals, as calculated on the cell viabilities in 5% and 0.05% solutions were in agreement in all tests. Based on these results, high intra-laboratory reproducibility was confirmed.In addition, the irritation category (irritant and non-irritant) was evaluated for 109 chemicals with STE test, globally harmonized system (GHS) classification, and European Union (EU) classification. The results of the evaluation found the STE classification to have an accuracy with GHS classification of 87% and with EU classification of 83%, which confirmed the excellent correspondence.The correspondence of STE rankings (1, 2, and 3) based on the prediction model by STE test with the eye irritation rankings by GHS (non-irritant, categories 2 and 1) and EU (non-irritant, R36, and R41) was 76% and 71%, respectively.Based on the above results, STE test was considered to be a promising alternative method for assessing eye irritation that has high intra-laboratory reproducibility as well as an excellent predictability of eye irritation.  相似文献   
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Rationale Conflicting results have been reported regarding the role of the nitric oxide (NO)–cyclic guanosine monophosphate (cGMP) pathway in the hippocampus on anxiety modulation. Objectives To investigate the effects of intrahippocampal injections of drugs that modify the NO–cGMP pathway in rats submitted to two animal models that are sensitive to anxiolytic drugs, the elevated plus-maze and the Vogel punished licking test. Materials and methods Male Wistar rats with cannulae aimed at the dentate gyrus of the dorsal hippocampus received microinjections of the NO synthase (NOS) inhibitors N G-nitro-L-arginine methyl ester (LNAME, 15–300 nmol/0.2 μl), N G-nitro-L-arginine (LNOARG, 50–300 nmol/0.2 μl), 7-nitroindazole (7NI, 10–100 nmol/0.2 μl), or the soluble guanylate cyclase inhibitor 1H-oxadiazolo-quinoxalin-1 one (ODQ, 10–100 nmol/0.2 μl), and were submitted to the elevated plus-maze. In a second group, the animals received 7NI, LNAME, or ODQ and were submitted to the Vogel punished licking test. To control for drug-induced changes in locomotor behavior, the animals were submitted to an open arena or to the Rota-rod test. Results All drugs increased the exploration of the open arms of the elevated plus-maze. They also increased the number of punished licks in the Vogel test, indicating an anxiolytic effect. The anxiolytic effect of LNAME was prevented by previous treatment with L-arginine (300 nmol/0.2 μl). Except for the lower dose of LNAME (15 nmol), administration of the NOS inhibitors or ODQ did not change exploratory activity in the open field nor cause any gross locomotor impairment in the Rota-rod test. Conclusion The results suggest that NO plays an anxiogenic role in the dentate gyrus of the dorsal hippocampus.  相似文献   
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Nitric oxide (NO) plays an important role in hippocampal long‐term potentiation (LTP), which is involved in memory processes. This led to the hypothesis that nitric oxide synthase (NOS) inhibitors will have disturbing effects on learning and memory. The aim of our study was to investigate the effects of the new selective neuronal and inducible NOS inhibitor 1‐ (2‐trifluoromethylphenyl) imidazole (TRIM) (10–50 mg/kg) on learning and memory and compare it to the nonselective NOS inhibitor 7‐NI (15–45 mg/kg) using different behavioral tests in Swiss mice, thus clarifying the role of neuronal NOS (nNOS) and endothelial NOS (eNOS) in cognitive processes. TRIM had no specific effect on either learning or memory parameters, while 7‐NI (30 mg/kg) disturbed spatial memory in the probe trial of the Morris water maze test, which was performed on the last day of the test. No differences between TRIM and the control groups were observed, while 7‐NI (30 and 45 mg/kg) significantly disturbed memory in the novel object recognition test. In the social transmission of food preference test, both TRIM (50 mg/kg) and 7‐NI (45 mg/kg) impaired hippocampal olfactory memory, but the total food consumption was also significantly decreased at these doses. In the passive avoidance test, TRIM did not disturb the performance, while memory impairment was observed, even with lower doses of 7‐NI. All of these results suggest that TRIM has no clear effect on cognitive impairment compared to 7‐NI and that inhibition of both nNOS and eNOS are necessary for the deterioration of memory processes.  相似文献   
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The lateral forebrain of zebra finches that comprises parts of the lateral nidopallium and parts of the lateral mesopallium is supposed to be involved in the storage and processing of visual information acquired by an early learning process called sexual imprinting. This information is later used to select an appropriate sexual partner for courtship behavior. Being involved in such a complicated behavioral task, the lateral nidopallium should be an integrative area receiving input from many other regions of the brain. Our experiments indeed show that the lateral nidopallium receives input from a variety of telencephalic regions including the primary and secondary areas of both visual pathways, the globus pallidus, the caudolateral nidopallium functionally comparable to the prefrontal cortex, the caudomedial nidopallium involved in song perception and storage of song-related memories, and some parts of the arcopallium. There are also a number of thalamic, mesencephalic, and brainstem efferents including the catecholaminergic locus coeruleus and the unspecific activating reticular formation. The spatial distribution of afferents suggests a compartmentalization of the lateral nidopallium into several subdivisions. Based on its connections, the lateral nidopallium should be considered as an area of higher order processing of visual information coming from the tectofugal and the thalamofugal visual pathways. Other sensory modalities and also motivational factors from a variety of brain areas are also integrated here. These findings support the idea of an involvement of the lateral nidopallium in imprinting and the control of courtship behavior.  相似文献   
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