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We have previously described a chicken heterophile antigenic determinant (CHAD-1) shared by Mycobacterium smegmatis and chicken tissues. We then demonstrated that CHAD-1 is present on several chicken glycoproteins and that its immunoreactive domains are highly branched asparagine-linked oligosaccharides terminating in N-acetylglucosamine residues. In the present study, we have shown that CHAD-1 is also expressed by mucin purified to homogeneity from a soluble mucus of chicken intestine. Another antigen found on chicken mucin is a chicken mucin-cross-reactive antigen (CMCRA). Antisera to this antigen were produced by immunization of rabbits with an enriched preparation of CHAD-1 isolated from the bursa of Fabricius. These antisera were absorbed with Mycobacterium smegmatis (to block the anti-CHAD-1 antibody) and with chicken serum, and then used for immunoperoxidase staining of chicken tissue sections for CMCRA. The latter antigen was detected in most medullary cells of the bursa, in epithelial cells and Hassal's corpuscles of the thymus, and in mucus-producing cells of the intestine, esophagus, trachea, and bronchi. Using Western immunoblot analysis, we demonstrated that CMCRA is expressed by a number of polypeptides extracted from bursal lymphoid cells. These polypeptides could not be detected in extracts of thymus, spleen, peripheral blood or bone marrow mononuclear cells.  相似文献   
23.
Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired chronic hemolytic anemia associated with an unusual susceptibility to hemolytic crisis, infection, and venous thrombosis which would be aggravated by a number of factors including surgery. We report a case of PNH undergoing percutaneous transluminal coronary angioplasty and discuss the corresponding perioperative management.  相似文献   
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PURPOSE: This study was an analysis of the soft and hard tissue changes of the facial profile after bilateral sagittal splitting osteotomy for mandibular setback of Taiwanese patients. PATIENTS AND METHODS: We collected pre- and postsurgical lateral cephalographs of 64 patients (28 males, 36 females) with skeletal Class III malocclusion who received combined orthodontic-surgical treatment with bilateral sagittal splitting osteotomy mandibular setback at Taipei Veterans General Hospital between 1994 and 2000. Nineteen cephalometric parameters of (14 linear, 4 angular, and the BS index) soft and hard tissues were measured at 1 week before treatment, and 2 months and 1 year after surgery, and analyzed by paired t test. RESULTS: Mean patient age was 20.0 +/- 1.6 years. The patients underwent an average of 7 mm mandibular setback at the osseous pogonion (Pog). Average setbacks at Pog and soft tissue pogonion (pog) were 5.54 mm and 4.85 mm, respectively, at 1 year after surgery. The setback ratio of Pog/pog was 1:0.88. The hard tissue relapse at Pog was 21% at 1 year after surgery. Improvement in prognathic profile was demonstrated by significant changes in the positions of Pog and pog, ANB angle, the distance from lower lip to esthetic line (E-L lip), and the BS index after surgery. However, compared with parameters obtained from a normal Taiwanese population, the cephalometric data of Pog, pog, and BS index still indicated mild prognathism. CONCLUSION: Although mandibular prognathism could be grossly improved by bilateral sagittal splitting osteotomy mandibular setback, a significant amount of relapse occurred within 1 year after surgery. The extent of the postoperatively preserved features showing mandibular prognathism should be a concern for both patients and physicians.  相似文献   
26.
Therapeutic limitations of argon laser trabeculoplasty.   总被引:3,自引:3,他引:0       下载免费PDF全文
Sixty-one patients (82 eyes) were studied after argon laser trabeculoplasty (ALT) to determine the lasting efficacy of such treatment. This investigation, now in its fourth year, was prospective, and the information derived was analysed with the aid of a computer. Success was defined as intraocular pressure (IOP) below baseline (22 mmHg). The mean follow-up time was 24.5 months, when the success rate was 74% compared with 75% at three months. Success declined to 45% at 42 months. No significant difference was noted when (a) first lasered eyes of all patients and those fellow eyes treated were analysed separately, (b) when right and left eyes were analysed separately, nor (c) when patients were divided into two treatment groups, (I) 100 burns at 1 W, and (II) 65 burns at 850 mW. Eight of 11 eyes showed progressive postlaser field loss despite below-baseline intraocular pressures. ALT is an alternative to carbonic anhydrase inhibitor therapy, with a success rate of 66.7% at two years. However, repeat ALT was successful in only 25% of patients seven months after treatment.  相似文献   
27.
(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine, HPMPC, and two HPMPC-related nucleoside analogs, (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine, HPMPA, and (2-phosphonylmethoxyethyl)guanine, PMEG, were evaluated for their antiviral activities against guinea pig cytomegalovirus (GPCMV) infection in guinea pig embryo (GPE) cells and human cytomegalovirus (HCMV) infection in human diploid fibroblast (MRC-5) cells. DHPG, 9-(1,3-dihydroxy-2-propoxymethyl)guanine, was used for comparison. The antiviral activity of HPMPC against GPCMV infection in vivo and its toxicity to Hartley guinea pigs were also evaluated. The 50% antiviral effective doses (ED50) of HPMPC, HPMPA, PMEG and DHPG against GPCMV infection in GPE cells were 0.22, 1.4, 0.07 and 62 microM, respectively; and against HCMV infection in MRC-5 cells, the ED50s were 0.51, 0.72, 0.01 and 17.5 microM, respectively. Their cytotoxic doses (CyD50) in GPE replicating cells were 84, 35, 1.4 and 700 microM, respectively and in MRC-5 cells were approximately 114, 31, 0.86 and 750 microM, respectively. Based on their calculated therapeutic indexes, HPMPC was the most potent and selective of the four compounds tested. In vivo, during acute infection, the spleen indexes of all infected animals that were treated with 1.25 to 5.0 mg/kg/day of HPMPC for 5 days were significantly reduced as compared with sham-treated animals. Virus infectivity titers in blood and various tissues of infected animals treated with HPMPC, 2.5 or 1.25 mg/kg/day were not significantly lower than those of the infected, sham-treated animals; with 5 mg/kg/day, infectivity titers in the blood, spleen, and salivary gland were significantly lower in HPMPC-treated than in sham-treated animals. However, HPMPC was toxic to guinea pigs especially at doses of 5 to 10 mg/kg/day. These data showed that HPMPC was highly active and selective in cultured guinea pig cells and human fibroblast cells against CMV infection but did not effectively inhibit GPCMV infection in guinea pigs at minimum toxic concentrations.  相似文献   
28.
路路通内酯的化学结构   总被引:4,自引:1,他引:3  
孙玉茹  孙友富 《药学学报》1996,31(6):437-440
用红外,质谱,1H,13CNMR和1H-13CCOLOC等光谱解析,确定了新化合物路路通内酯的结构为3-羰基-11α,12α-环氧-13β-氧-齐墩果-28β-酸-13,28-γ-内酯,命名为路路通内酯。  相似文献   
29.
抗hER合成肽单克隆抗体的制备与鉴定   总被引:1,自引:0,他引:1  
王振明 Hong.  T 《免疫学杂志》1997,13(4):263-265
用合成的人雌激素受体(hER)抗原决定簇多肽(氨基酸序列从151~165)与KLH的偶联物为抗原,免疫BALB/C小鼠,经鼠-鼠杂交,ELISA和免疫细胞化学法筛选,有限稀释克隆化,得到一株分泌抗hER合成肽的杂交瘤细胞株(2B12)。用ELISA法测定。该纯化抗体10ng/ml仍与抗原反应,其免疫球蛋白为IgG2a.k。与MCF-7乳腺癌细胞溶解蛋白的Westernblot分析,在分子量67kD  相似文献   
30.
A randomized trial was conducted to compare the efficacy and safety of fluconazole versus that of amphotericin B in the treatment of candidemia in non-neutropenic adults. Enrollment was stratified by disease severity (APACHE II score). Patients were randomized (1:1) to receive amphotericin B 0.6 mg/kg/day (cumulative dose 8 mg/kg) or fluconazole 800 mg intravenous loading dose, then 400 mg daily for four weeks (intravenous for at least 10 days). Patients were monitored for six months. A total of 106 patients were enrolled. A protocol amendment implemented midway through the trial required patients to be removed from the study and treated with amphotericin B if species identification indicated candidemia due toCandida glabrata orCandida krusei. Baseline characteristics were similar for the two groups; 103 patients (fluconazole, 50; amphotericin B, 53) met the major enrollment criteria. The intention-to-treat analysis indicated successful therapy in 50% of fluconazole recipients compared to 58% of the amphotericin B group (p=0.39; one-sided 95% Cl, –8 to 24%). The efficacy analysis included 84 patients (fluconazole, 42; amphotericin B, 42); successful outcomes were observed in 57% and 62% of cases in the fluconazole and amphotericin B groups, respectively (p=0.66: one-sided 95% Cl, –12 to 22%). The mortality at day 14 for the fluconazole group was 26% and for the amphotericin B group 21% (p=0.52; chi-square test) and remained similar throughout the course of follow-up. Drug-related adverse events were more frequent with amphotericin B than with fluconazole and prompted switching of therapy for two (4%) and zero cases, respectively. Fluconazole and amphotericin B were associated with similar clinical response rates and survival in the treatment of candidemia among non-neutropenic patients; however, drug-related adverse events were more frequent with amphotericin B.  相似文献   
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