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81.
"Ondol" is a Korean unique heating system. It is a specific radiant floor heating system using combustion heat of briquette or timber in Korea. Such traditional "Ondol" is changed to radiant heating system with pipe-coil embedded in the floor or slab. This study has contributed to the understandings of the transient behaviours of Ondol-heated floor panels and enclosure exposed to this type of heating system. The result is that the water supply temperature had a large effect on the rate of increase in floor surface and room air temperature. But, in spite of a higher water supply temperature, the heat flow rate was not increased considerably. The shallow pipe embedding depths, of course, result in a low heat flow rate.  相似文献   
82.
In summer 1991 an outbreak of a Salmonella enteritidis epidemic involving about 600 cases of gastroenteritis occurred at one of the leading pharmaceutical companies in southwestern Germany. The main source was a cold fruit soup, in addition Salmonella were isolated from meat strips and a curd cheese which were used for a salad dressing. A total of 2300 contaminated food portions were served resulting in an attack rate of about 25%. The possible origin could have been an asymptomatic Salmonella-positive member of the kitchen personnel who was the only one who was involved with the preparation of all the incriminated foods. A further spread of the epidemic and especially the possible contamination of pharmaceuticals was avoided by the timely and adequate reaction of the company's occupational medical service. This case exemplifies how classical crisis management, "increased initiative on one's own for prevention of infections in all areas of food processing" (Steuer) and finally the cooperation of the company with different institutions of the public health authorities contribute to the control of such a catastrophic scenario.  相似文献   
83.
Analysis of the S-phase fractions (SPF) measured by in vitro thymidine labeling, morphological appearances, and estrogen receptor (ER) assays of primary invasive breast carcinomas demonstrated several interrelationships. Lobular, mucinous, tubular, and adenocystic carcinomas consistently had low SPF and were usually positive for ER. The same was true for the carcinomas of no special histologic type [the not otherwise specified (NOS) group of E. R. Fisher including "infiltrating ductal" and undifferentiated carcinomas] with minimal anaplasia. Medullary, atypical medullary, and morphologically unclassifiable carcinomas with marked nuclear anaplasia nearly always had high SPF and were usually negative for ER. High SPF was associated with advanced stages of carcinoma initially or with early recurrence following mastectomy.  相似文献   
84.
The serum of some patients with insulin-resistant "diabetes" contains antibodies that bind to and block the cell membrane receptors for insulin. In this report, we have characterized the effects of the antireceptor antibodies on the interaction of (125)I-insulin with its receptor on the human lymphoblastoid cell line IM-9. Up to 95% of specific insulin binding can be inhibited by pretreatment of the cells with these immunoglobulins. The onset of the inhibitory effect is time- and temperature-dependent, and the effect is reversed extremely slowly if the cells are suspended in a large excess of antibody-free buffer. These features of antibody binding can be easily distinguished from those for insulin binding to its receptor. The inhibitory effect of the antibodies can be reversed by exposure of the cells to conditions known to elute surface immunoglobulins. The three antireceptor sera studied appear to alter the insulin-receptor interaction in different ways. Two antisera markedly reduce receptor affinity through combined effects on the insulin association and dissociation rates, and, additionally, have smaller effects on available receptor number. A third antiserum primarily affects available receptor number and has little effect on receptor affinity. All three antisera inhibit the capacity of insulin to promote negatively cooperative site-site interactions among insulin receptors. The data suggest that these autoantibodies to the insulin receptor bind to different determinants on the receptor and may therefore be useful as unique probes of insulin receptor structure and function.  相似文献   
85.
An ab initio restricted Hartree-Fock calculation utilising the standard 6-31G basis set was used to calculate total energies after PM3 calculations of energy-optimised geometries for the five-membered alumino-silicate framework rings cluster for a total of ten T sites. Calculations have shown that in the absence of protons or other ions, the most favourable sites for 1A1, 2A1 and 3A1 substitution of Si are the T6, T1 and T9 sites respectively. With more Al atoms replacing Si in a cluster, T-O bond lengths and T-O-T angles show lengthening and sharpening trends respectively, which indicates that the structure is distorted to a more relaxed symmetry with Obr atoms moving outwards. The calculated bond lengths and angles have been shown to match the values observed in previous studies, including those for a four-membered alumino-silicate single ring cluster. Based on the optimised five-membered alumino-silicate framework rings model, a further ab initio HF calculation has been conducted on ring breakage for releasing Al(Q3) and Si(Q3) centres to form T(OH)4 and HOT(OM)3 tetrahedra under local and highly alkaline environment. The obtained results suggest that Al(Q3) compared with Si(Q3) breaks more readily with the exothermal reaction enthalpy being in excess of -244.4 kJ/mol, while the most reactive Si(Q3) centre shows an exothermal reaction enthalpy of only -33.8 kJ/mol. This indicates that Al dissolves in preference to Si in local environment. The dissolution mechanism of the five-membered Al-Si framework rings model in highly alkaline solutions has been suggested to be composed of an ion-pairing reaction and an interaction between the remaining broken ring cluster triple bond TOH and MOH.  相似文献   
86.
Self expandable stents were placed percutaneously in 105 patients with malignant biliary obstruction. Stent diameter was 1 cm; length, 3.5-10.5 cm. Of the 60 patients with common bile duct obstruction, 50 died 0.2-12 months (median 3 months) after stent insertion. Two patients developed recurrent jaundice and cholangitis after 6 and 12 months, respectively. One patient underwent reintervention. Ten patients, one after a successful reintervention, were alive without jaundice 1-8 months (median 5 months) after stent placement. Of the 45 patients with hilar lesions, 26 died 0.7-18 months (median 5 months) after stent placement, five of them with signs of cholangitis. Nineteen are alive 1-21 months (median 7 months) afterwards. Reinterventions were carried out in 13 patients (29%). The most common cause of stent malfunction was tumour overgrowth. Stent-related complications were seen in three patients.  相似文献   
87.
Exposure of mammalian cells to ultraviolet (UV) light elicits a cellular response and can also lead to apoptotic cell death. In this report, we show that a 36-kDa myelin basic protein (MBP) kinase detected by an in-gel kinase assay can be dramatically activated during the early stages of UV irradiation-triggered apoptosis of A431 cells. Immunoblot analysis revealed that this 36-kDa MBP kinase could be recognized by an antibody against the C-terminal regions of a family of p21Cdc42/Rac-activated kinases (PAKs). By using this antibody and a PAK2-specific antibody against the N-terminal region of PAK2 as studying tools, we further demonstrated that UV irradiation caused cleavage of PAK2 to generate a 36-kDa C-terminal catalytic fragment and a 30-kDa N-terminal fragment in A431 cells. The appearance of the 36-kDa C-terminal catalytic fragment of PAK2 matched exactly with the activation of the 36-kDa MBP kinase in A431 cells upon UV irradiation. In addition, UV irradiation also led to activation of CPP32/caspase-3, but not ICH-1L/caspase-2 and ICE/caspase-1, in A431 cells and the kinetics of activation of CPP32/caspase-3 appeared to correlate well with that of DNA fragmentation and of cleavage/activation of PAK2, respectively. Moreover, blockage of activation of CPP32/caspase-3 by pretreating the cells with two specific tetrapeptidic inhibitors for caspases (Ac-DEVD-cho and Ac-YVAD-cmk) could significantly attenuate the extent of cleavage/activation of PAK2 induced by UV irradiation. Collectively, the results demonstrate that cleavage and activation of PAK2 can be induced during the early stages of UV irradiation-triggered apoptosis and indicate the involvement of CPP32/caspase-3 in this process.  相似文献   
88.
89.
Preparative gel electrophoresis was used to separate and purify extracellular, capsular and lipopolysaccharides (EPSs, CPSs, and LPSs, respectively) from crude bacterial extracts. The procedure effectively separates CPS from LPSs. In addition discreet size ranges of these various polysaccharides can be isolated. The 'rough' (R-type), 'smooth' (S-type), and 'semi-smooth' LPSs were separated from one another. In addition different size classes of 'semi-smooth', or S-type LPS, can be separated. This procedure was demonstrated for diverse bacterial species, including the soil bacteria Rhizobium fredii, and the enteric bacterial species, Salmonella enteritidis and Proteus mirabilis. In the latter case, it was also possible to separate capsular polysaccharide from its lipid-bound form.  相似文献   
90.
Using a directed forgetting task, the authors tested in 2 experiments the hypothesis that repressors would be superior to controls in forgetting negative experimental material. Consistent with previous studies, there was an overall directed forgetting effect, with significantly more to-be-remembered material recalled than to-be-forgotten (TBF) material. In both experiments, repressors forgot more negatively valenced words in the TBF set than did nonrepressors, suggesting that repressors have an enhanced capability for using retrieval inhibition. The data offer preliminary support for a cognitive account of repressors' deficits in recalling negative autobiographical memories.  相似文献   
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