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排序方式: 共有846条查询结果,搜索用时 15 毫秒
21.
Zhao P Cao J Zhao LJ Qin ZL Ke JS Pan W Ren H Yu JG Qi ZT 《第二军医大学学报》2006,27(5):506-506
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein. 相似文献
22.
Interruption of the contrast column during inspiration can lead to non‐diagnostic CT pulmonary angiograms. The importance of this artefact will increase with more CT studies being performed for pulmonary embolism on multidetector row CT. We describe here an instance of such an artefact and discuss its aetiology. 相似文献
23.
We report a case of an assisted pregnancy in an asymptomatic woman who was found to have an extrauterine mass on ultrasound and MRI. This complex mass had equivocal imaging features and was found to be a ruptured ovarian ectopic pregnancy at surgery. This case illustrates that vigilance is required regarding the possibility of coexisting ectopic and intrauterine pregnancy following assisted conception, even in entirely asymptomatic cases. 相似文献
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Mary Molewyk Doornbos Gail Landheer Zandee Barbara Timmermans Jesse Moes Joleen DeGroot Megan DeMaagd-Rodriguez Julia Smit-Scholman Molly Zietse Emily Heitsch Morgan Quist 《Archives of Psychiatric Nursing》2018,32(4):524-529
Depression and anxiety are mental health issues that disproportionately affect urban, ethnically diverse, impoverished women. Using community based participatory research and in the context of long-term partnerships between a nursing department and underserved neighborhoods that are predominately Black, Hispanic, and White respectively, supportive/educative groups were offered. The study employed a quasi-experimental, nonequivalent comparison group pretest-posttest design. Seventy-two women aged 17–88?years participated. Repeated measures ANOVA indicated a significant increase in knowledge for self-care for depression and anxiety and a significant decrease in anxiety and depression symptomatology from before to after the group sessions. 相似文献
26.
Wolfgang Schoels MD David Steinhaus MD W. Ben Johnson MD Gilles OHara MD Joerg O. Schwab MD Inge Jenniskens MSc Paul J. DeGroot MS Feng Tang PhD Erhard Helmling MD EnTrust Clinical Study Investigators 《Heart rhythm》2007,4(7):879-885
BACKGROUND: Previous studies in implantable cardioverter-defibrillator (ICD) patients demonstrated the efficacy and safety of antitachycardia pacing (ATP) for rapid ventricular tachycardias (VT). To prevent shock delay in case of ATP failure, a new feature (ATP during charging) was developed to deliver ATP for rapid VT while charging for shock. OBJECTIVE: The purpose of this study was to determine the efficacy and safety of this new feature. METHODS: In a prospective, nonrandomized trial, patients with standard ICD indication received an EnTrust ICD. VT and ventricular fibrillation (VF) episodes were reviewed for appropriate detection, ATP success, rhythm acceleration, and related symptoms. RESULTS: In 421 implanted patients, 116 VF episodes occurred in 37 patients. Eighty-four (72%) episodes received ATP during or before charging. ATP prevented a shock in 58 (69%) of 84 episodes in 15 patients. ATP stopped significantly more monomorphic (77%) than polymorphic VTs (44%, P = .05). Five (6%) episodes accelerated after ATP but were terminated by the backup shock(s). No symptoms were related to ATP during charging. In four patients, 38 charges were saved by delivering ATP before charging. Of 98 induced VF episodes, 28% were successfully terminated by ATP versus 69% for spontaneous episodes (P <.01). CONCLUSION: Most VTs detected in the VF zone can be painlessly terminated by ATP delivered during charging, with a low risk of acceleration or symptoms. ATP before charging allows delivery of two ATP attempts before shock in the same time that would otherwise be required to deliver only one ATP plus a shock. It also offers potential battery energy savings. 相似文献
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28.
Gardine CA Gentile F Pellegrini C Giallauria F Torelli G Kouki T DeGroot L 《Journal of endocrinological investigation》2003,26(4):294-300
Oral tolerance is the mechanism by which the immune system remains unresponsive to orally administered soluble antigens. Mice immunized with human TG (hTG), resulting in the induction of experimental autoimmune thyroiditis (EAT), provide an ideal in vivo system in which to examine oral tolerance to hTG. In the present study, we characterize epitopes of hTG that are capable of inducing oral tolerance. hTG is a large homodimeric protein, 660 Kd. The limited proteolysis of hTG using trypsin (TR) generates several smaller fragments of hTG ranging in size from 29 Kd to 145 Kd. Using hTG fragments h1TR (residues 1-521), h4bisTR (residues 2513-2713), h6TR (residues 522-1626), and h7TR (residues 1627-2512), prepared from both iodine rich and iodine poor hTG, we investigated the ability of these fragments to induce oral tolerance. The oral administration of iodine rich h6TR or h7TR suppresses hTG specific immune responses in a manner similar to whole hTG. In contrast, the oral administration of iodine rich h1TR or h4bisTR exacerbates hTG specific immune responses. Unlike iodine rich h1TR or h4bisTR, the oral administration of iodine poor h1TR or h4bisTR fails to augment hTG specific immune responses. In fact, h4bisTR suppresses hTG specific immune responses. These results indicate that hTG contains multiple epitopes that differentially affect oral tolerization. Tolerogenic epitopes reside within fragments h6TR and h7TR. The removal of iodine, and presumably hormone, from h4bisTR converts an immunogenic epitope to a tolerogenic epitope. 相似文献
29.
Compensated low-dose 131I therapy of Graves' disease 总被引:1,自引:0,他引:1
To minimize the high rate of residual thyrotoxicosis encountered in low-dose 131I therapy of Graves' disease, we have treated 62 patients with a low-dose 131I protocol that includes a compensation for thyroid size. Dose varied between 40 muCi retained/g for glands of normal size to 100 muCi/g for glands of 100 g or greater. Mean dose was 51.9 muCi/g. At 1 year after therapy, 66.1% of subjects were euthyroid, 9.7% hypothyroid, and 24.2% hyperthyroid, a significant improvement (P less than 0.01) over our previous experience using 50 muCi/g independent of gland size. Several factors, other than 131I dose, which might influence the outcome of therapy, were investigated. Initial free thyroxine index observed before therapy was found to have prognostic significance. Hypothyroidism developed only in patients having an initial free thyroxine index of 22.5 or less (about 2.5 times the upper limit of normal in our laboratory). 相似文献
30.
Chen AC Temple MM Ng DM Verzijl N DeGroot J TeKoppele JM Sah RL 《Arthritis and rheumatism》2002,46(12):3212-3217
OBJECTIVE: To determine whether increasing advanced glycation end products (AGEs) in bovine articular cartilage to levels present in aged human cartilage modulates the tensile biomechanical properties of the tissue. METHODS: Adult bovine articular cartilage samples were incubated in a buffer solution with ribose to induce the formation of AGEs or in a control solution. Portions of cartilage samples were assayed for biochemical indices of AGEs and tested to assess their tensile biomechanical properties, including stiffness, strength, and elongation at failure. RESULTS: Ribose treatment of cartilage induced increases in tissue fluorescence, absorbance, and pentosidine content (P < 0.001 for each comparison) by amounts similar to those that occur during aging in humans. Ribose treatment of cartilage also induced an increase in dynamic modulus (60% increase) and strength (35% increase), and a decrease (25% decrease) in strain (P < 0.001 for each comparison). CONCLUSION: The concomitant increase in AGEs and alteration of tensile properties of cartilage after ribose treatment suggest that aging-associated changes in AGEs have functional consequences for this tissue. The AGE-associated increases in strength and stiffness of cartilage may be beneficial by counteracting the decreases in these properties that are associated with degeneration. Conversely, the AGE-associated decrease in failure length, or increase in brittleness, together with increased stiffness may predispose cartilage to increased stress concentration, fracture, and aging-associated biomechanical dysfunction. 相似文献