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751.
Leventon  GS; Kulkarni  SS; White  RA; Zander  AR 《Blood》1986,68(5):1003-1007
Ways of accelerating recovery of the mucous membrane immune system in lethally irradiated mice following syngeneic bone marrow transplantation were studied over a 35-day period by quantification of jejunal intraepithelial lymphocytes (IELs) and lamina propria plasma cells. Recovery after a low bone marrow dose allowing 100% animal survival (LBM) was compared with a high (five times minimal) dose (HBM), or a minimal dose augmented with equal numbers of buffy coat cells (LBM + BC) or small gut mucosal lymphocytes (LBM + GL). The maximal decline and subsequent peak repopulation of IELs were: LBM, days 7 through 14, peaking suboptimally by day 28; HBM, day 14, peaking suboptimally but higher than LBM by day 35; LBM + BC, days 11 through 14, peaking at control levels by day 35; and LBM + GL, day 7, peaking at control levels by day 28. The IEL decline was most severe with LBM and HBM treatment and least with LBM + GL. All transplant groups experienced maximal plasma cell decline by day 7. LBM had the most severe depletion, and LBM + GL had the least. Recovery to control levels for the LBM, HBM, LBM + BC and LBM + GL groups occurred by days 28, 21, 21, and 14, respectively. In all instances, greater than 95% of the plasma cells were IgA positive.  相似文献   
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753.
Over the past 6 years, the authors evaluated 300 patients with hepatoma as part of phase 1 and 2 treatment protocol trials. Analysis of the available clinical data and radiographic studies revealed 22 patients (7.3%) with skeletal metastases demonstrated by radiography, computed tomography (CT), and/or nuclear scintigraphy. The plain film appearance of skeletal metastases from hepatoma was osteolytic in all cases. CT scanning best demonstrated the expansile, destructive nature of these metastases, which were often associated with large, bulky soft-tissue masses. Skeletal metastases from hepatomas demonstrated increased radiotracer uptake on standard bone scans and were gallium avid, similar to the hepatoma itself. In addition, they could be targeted therapeutically with I-131 antiferritin immunoglobulin. The most frequent sites of skeletal metastases were the ribs, spine, femur, pelvis, and humerus. An initial symptom in ten patients was skeletal pain corresponding to the osseous metastases. In five patients, pathologic fractures of the proximal femur or humerus developed and required total hip replacement or open-reduction internal fixation. Patients with long-standing cirrhosis or known hepatocellular carcinoma who also have skeletal symptoms should be evaluated for possible osseous metastases.  相似文献   
754.
目的:为了了解叶绿素衍生物(CPD4)口服后在膀胱粘膜内含量变化的状况,以便为临床应用提供实验依据。方法:13条实验犬分为3个不同剂量组,应用荧光检测法作服药后不同时段膀胱粘膜CPD4含量的测定。结果:CPD4用于实验犬的合适剂量是100mg/kg,明显低于此值将显著影响组织的吸收,从而降低光动力作用。在禁食组中,组织内吸收的最高峰值出现在服药后2h,而进食组却推迟出现在服药后6 ̄12h。结论:为  相似文献   
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756.
张力  张丹参  张士善 《药学学报》1991,26(6):411-414
采用侧脑室微最注射法证明,谷氯酸受体哑型激动剂红藻氨酸(KA)可依剂量性地升高大鼠血压和加快心率。预先给予GABA合成抑制剂氮基脲140 mg/kg ip或GABA拮抗剂印防己毒1 mg/kg iv均可明显增强KA的作用;而GABA转氨酶抑制剂氨氧乙酸25μg/rat icv明显减弱KA的作用。结果表明,脑内GABA能神经元功能受抑,KA的中枢性心血管效应增强。从而推测,脑内GABA能神经元与谷氯酸能神经元之间相互制约,共同参与中枢性调节心血管的活动。  相似文献   
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759.
Huang  CH; Reid  ME; Xie  SS; Blumenfeld  OO 《Blood》1996,87(9):3942-3947
The Wright (Wra/Wrb) blood group polymorphism is defined by an allelic change (Lys658Glu) in the band 3 protein; nevertheless, the Wrb antigen apparently requires glycophorin A (GPA) for surface presentation. To gain insight into the structural basis for this protein-protein interaction and delineate its relationship with Wrb antigen expression, we investigated GPA and band 3 sequence polymorphisms occurring in rare humans and nonhuman primates. The lack of GPA or amino acid residues 59 through 71 of GPA results in the absence of Wrb from human red blood cells (RBCs) exhibiting the MkMk, En(a-), or MiV phenotype. However, the SAT homozygous cells carried a Glu658 form of band 3 and a hybrid glycophorin with the entire GPA extramembrane domain from residues 1 through 71, yet expressed no Wrb antigen. This finding suggests that formation of the Wrb antigenic structure is dependent on protein folding and that the transmembrane junction of GPA is important in maintaining the required conformation. Comparative analyses of GPA and band 3 homologues led to the identification in the interacting regions of conserved and dispensable amino acid residues that correlated with the Wrb positive or negative status on nonhuman primates. In particular, the chimpanzee RBCs cells expressed Wrb and the Glu658 form of band 3, which is identical to humans, but their GPA contained the Gly rather than Arg residue at position 61. Taken together, the results suggest that (1) Arg61 of GPA and the proposed Arg61-Glu658 charge pair are not crucial for Wrb antigen exhibition and (2) the role of GPA for interaction with band 3, including Glu658, probably involves a number of amino acid residues located in the alpha-helical region and transmembrane junction.  相似文献   
760.
Untreated neoplasms of the neck (tumors of the oropharynx, supraglottic area, carotid body, and thyroid, in addition to malignant lymphadenopathy) were evaluated in 23 patients with magnetic resonance (MR) imaging. The results were compared with computed tomographic (CT) scans in 20 patients. Contrast between tumor and fat was best on relatively T1-weighted images (500/30-35 [TR msec/TE msec]), whereas separation of tumor and muscle was best with relatively T2-weighted pulse sequences (1,500/90). Balanced images (1,500/30-35) provided best overall image quality and best demonstrated vascular anatomy. MR imaging was usually superior to CT in showing the relationship of tumor mass to muscle. MR imaging and contrast material-enhanced CT were equivalent in most patients in defining vascular anatomy, but MR imaging was superior when intravenous contrast material was not administered. However, CT was more helpful in showing bone and cartilage anatomy, and in some patients CT also was better in showing airway abnormalities. Despite these limitations, MR imaging is a promising imaging technique for studying neoplasms of the neck.  相似文献   
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