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991.
992.
993.
BackgroundRecent studies have suggested that allergic rhinitis is closely related to bronchial asthma, reflecting the "one airway-one disease" hypothesis. It is unclear if the effects of pranlukast, a leukotriene-receptor antagonist, are consistent with this hypothesis.ObjectiveThe goal of the study was to determine if pranlukast has effects on the upper and lower airways through a comparison of the effects of fexofenadine and pranlukast on airway hyperresponsiveness in non-asthmatic patients with cedar pollinosis before the Japanese cedar pollen season and during the peak pollen season.MethodsPatients received fexofenadine hydrochloride plus oral mequitazine (fexofenadine group) or pranlukast hydrate plus oral mequitazine (pranlukast group) as an initial treatment. Subsequent changes in airway responsiveness to acetylcholine were measured.ResultsAmong patients in whom coughing developed during the peak pollen season, airway responsiveness significantly increased in the fexofenadine group. In the pranlukast group, airway responsiveness did not increase significantly, regardless of the presence or absence of coughing.ConclusionsThe results indicate that pranlukast hydrate inhibits airway hyperresponsiveness in non-asthmatic patients with Japanese cedar pollinosis. In turn, this suggests that cysteinyl leukotrienes have a role in increased airway responsiveness.  相似文献   
994.
We present herein a case of a patient who was clinically diagnosed as having a granulocyte-colony stimulating factor (G-CSF)-producing tumor on the basis of the close correlation of the hematological parameters with the tumor status and his high serum G-CSF level. A 76-year-old male patient underwent transthoracic radical esophagectomy for advanced carcinoma of the lower esophagus. His leukocyte count and serum G-CSF level were markedly high at 24 260/μl and 134 pg/ml, respectively, before the operation. By immunohistochemical staining of the resected tumor, focal but obvious expression of G-CSF was demonstrated in the cytoplasm of cancer cells, and neutrophilic infiltration was histologically observed in adjacent struma of the tumor invasion front. After surgery, the leukocyte count decreased to a nearly normal level but increased again when the disease recurred in the pleura and lymph nodes 5 months later. Although palliative chemoradiotherapy decreased the leukocyte count to a normal level transiently, leukocyte count again markedly increased when metastatic disease occurred. The leukocyte count reached 78 060/μl the day before the patient died.  相似文献   
995.
The incidence of multidrug-resistant Pseudomonas aeruginosa (MDRPA) and metallo-beta-lactamase (MBL)-producing P. aeruginosa has increased worldwide. The treatment options are limited for infectious diseases caused by these two organisms. The use of colistin has been of recent interest in cases involving both types. We report the case of a 74-year-old man with acute myeloid leukemia who was successfully treated with intravenous colistin for maxillary sinusitis and orbital cellulites due to MBL-producing MDRPA during neutropenia, and then for pneumonia caused by the bacteria after the recovery of neutrophil counts.  相似文献   
996.
997.
Atomic force microscopy of native human metaphase chromosomes in a liquid   总被引:1,自引:0,他引:1  
The present study introduces a method for obtaining three-dimensional images of native (i.e., unfixed) chromosomes by atomic force microscopy (AFM) in a liquid. Human metaphase chromosomes were isolated from a human lymphoblast-like cell line, K562, by the hexylene glycol procedure according to Wray and Stubble- field (1970), adsorbed on a silane-coated glass slide, and observed in a dynamic force mode (i.e., intermittent contact mode) of AFM in a hexylene buffer solution. In adequate operating conditions, the shape of chromosomes with paired chromatids was clearly and three-dimensionally observed by AFM. At high magnification, globular or fibrous structures about 50 nm thick could be found on the surface of each chromaid, implying that chromatin fibers were strongly wound or twisted in the chromatid. Thus, AFM imaging enabled the direct visualization of native chromosomes in a liquid at high resolution--which is comparable with that of scanning electron microscopy--and can serve to analyze the mechanism of chromosome condensation and separation in relation to the structure of chromosomes.  相似文献   
998.
To investigate the long-term effects of c-src deficiency on skeletal and dental tissues, we examined the lower jaws and long bones of c-src gene knockout (c-src KO) mice by histological and histochemical methods. Numerous multinucleated osteoclasts were distributed throughout the mandible in 5-wk-old c-src KO mice, but by 14 wk they had almost completely disappeared from the alveolar bone, leaving tartrate-resistant acid phosphatase (TRAP)-positive layers along the bone surface. Deposition of osteopontin-positive mineralized tissue, reminiscent of acellular afibrillar cementum (AAC), was confirmed along the TRAP-positive bone surface at 14 wk. The layer progressively thickened up to 21 months. A comparable mineralized layer was noted along the trabeculae of long bones as thickened cement lines. In the periostin-rich areas of jaw bones, but not in the long bones, portions of AAC-like mineralized layers were often replaced with and/or covered by acellular extrinsic fiber cementum (AEFC)-like tissue. These data suggest that the deposition of AAC-like mineralized tissue is a general phenomenon that may occur along inert or slowly remodeling bone surfaces under conditions characterized by reduced bone-resorbing activity, whereas the induction of AEFC-like tissue seems to be associated with the expression of certain molecules that are particularly abundant in the microenvironment of the periodontal ligament.  相似文献   
999.
We investigated whether natriuretic peptide (NP) acts as an endogenous antipyretic inside and/or outside the blood-brain barrier in rats made febrile by systemic administration of bacterial endotoxin (lipopolysaccharide; LPS). Intravenous (i.v.) injection of LPS induced a triphasic fever, the second phase of which was significantly enhanced by an i.v. injection of the NP receptor (A-type and B-type) antagonist HS-142-1, a glucose-caproic acid polymer. In contrast, the same antagonist (i.v.) had no effect on the fever induced by i.v. injection of interleukin (IL)-1beta. An i.v. administration of HS-142-1 enhanced the LPS (i.v.)-induced IL-1beta response in the rat spleen. An i.v. treatment with atrial NP (ANP) significantly attenuated the second phase of the LPS-induced fever. On the other hand, i.c.v. injection of the above-mentioned NP receptor antagonist resulted in an augmentation of the third phase of the fever induced by i.v. administration of LPS, the same phase that was attenuated by ANP given i.c.v. When given intracerebro-ventricularly (i.c.v.), the antagonist had no effect on the fever induced by i.v. IL-1beta. Finally, the fever induced by i.c.v. injection of LPS was not affected even by an i.c.v. administration of the antagonist. These results suggest that the production of pyrogenic cytokines (such as IL-1beta) that follows i.v. LPS injection may be inhibited by NP acting outside the blood-brain barrier, leading to an inhibition of the fever. In contrast, inside the blood-brain barrier NP may inhibit cytokine-independent mechanisms present within the rat brain that mediate LPS (i.v.)-induced fever.  相似文献   
1000.
Porous linear-polymer penetrating networks (semi-IPNs) were prepared by the radical polymerization of acrylic acid (AAc) inside porous poly(N-isopropylacrylamide) hydrogels with "nano-sized tract networks (nano-tracts)." The deswelling behavior was investigated by measuring the time course of the swelling ratio change of the semi-IPNs just after the temperature or pH was changed. Although the incorporation of PAAc linear chains into the PNIPAAm hydrogel networks should facilitate deswelling, nonporous semi-IPNs showed only a slow thermoresponse under low pH conditions, and a slow pH-response under a high temperature. On the other hand, the porous semi-IPNs showed a rapid deswelling in response to either a change in pH or temperature, regardless of the environment, presumably due to the nano-tracts through which the water was rapidly released from the hydrogel without any interference by network shrinking. The novel network design of these nano-tracted semi-IPNs may be useful for high performance, dual molecule-release functions.  相似文献   
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