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1.
张旭东  郭树忠 《医学争鸣》2005,26(18):1716-1718
CTLA4-Ig是一种融合免疫球蛋白,可以选择性地阻断CD28与B7的信号传导通路,导致T细胞免疫失能,诱导对特异性抗原的免疫耐受. 本文介绍了其生物学特性、免疫诱导耐受机制及在异体移植方面的研究进展和局限性,其在异体移植方面展示了良好的应用前景.  相似文献   
2.
反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量   总被引:7,自引:0,他引:7  
倪坤仪  王建  陈健  郁建  屠树滋 《药学学报》1994,29(8):624-633
反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量倪坤仪,王建,陈健,郁建,屠树滋(中国药科大学210009)含牛黄的中成药种类很多,在医疗中具有广泛的用途。中药牛黄中主要成分为胆汁酸和胆红素。本文主要研究用HPLC法测定牛黄以及含牛黄中成药中胆汁酸的...  相似文献   
3.
新生儿和儿童乙肝免疫   总被引:3,自引:1,他引:2  
自1991年WHO提出将乙型肝炎病毒(HBV)疫苗纳入新生儿计划免疫以来,绝大多数国家新生儿HBV疫苗接种覆盖率平均在90%以上,婴儿HBV疫苗接种覆盖率为85%-99%.我国HBsAg携带率从10.19%下降到0.2%-3.2%.不同地区新生儿和儿童全程接种率、首针及时接种率、免疫覆盖率差异较大.对不同新生儿和儿童HB免疫尚需注意的问题如HBV疫苗接种程序和接种剂量,早产、低体质量儿的免疫接种,HBsAg阳性母亲子女的免疫接种和母乳喂养,抗-HBs保护时间和加强免疫问题.  相似文献   
4.
Summary The venous architecture in donor flaps was observed in 17 fresh cadavers by injection of latex or ink into the vessels or by making corrosion-cast specimens. The pattern of the veins resembles that of the arteries, with the difference that there is another set of venous trunks which do not accompany the arteries. Because these trunks are of larger caliber, they are the main drainage route for flaps. There are three types of drainage based on the anatomical architecture: 1) the superficial trunk is the main drainage path; 2) the deep trunk is the main path; 3) both superficial and deep veins are involved. These morphological considerations are the basis for selection of veins for anastomosis in microsurgery. The axial veins in temporal, frontal and facial flaps on the dorsum of the hand and the foot usually loosely accompany the axial arteries. The characteristics of these vascular pedicules should be studied in transplant operation.
Bases anatomiques du drainage veineux des lambeaux cutanés libres
Résumé Le drainage veineux des lambeaux cutanés libres a été étudié sur 17 cadavres frais par injection de latex ou d'encre dans les vaisseaux, ou en réalisant des moulages par injection-corrosion. La distribution des veines ressemble à celle des artères à la différence près qu'il existe des troncs veineux qui n'accompagnent pas les artères. Ces troncs ont un calibre plus important et représentent une voie de drainage principale pour les lambeaux. On peut individualiser trois types de drainages basés sur l'architecture veineuse : 1. Le tronc superficiel est la principale voie de drainage ; 2. le tronc profond est la principale voie; 3. les veines superficielles et profondes sont impliquées simultanément. Ces considérations morphologiques sont les bases de la sélection des axes veineux pour les anastomoses en micro-chirurgie. Les veines axiales au niveau temporal, frontal et facial et pour les lambeaux de la face dorsale de la main et du pied sont habituellement relativement éloignées du trajet artériel. Les caractéristiques de ces pédicules veineux doivent être précisées pour la réalisation des lambeaux.
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5.
Solitary fibrous tumours are infrequent neoplasms based in the pleura that are predominantly benign with malignant pathology and behaviour described in 10–36% of cases. Extrathoracic solitary fibrous tumours (ESFTs) have been considered separately to their intrathoracic counterparts and comprise a third of all solitary fibrous tumours. The extrathoracic location was identified as an adverse prognostic factor for local recurrence but not for metastatic disease. So far, there have not been any reports of solitary fibrous tumours demonstrating caval infiltration. We present a case of a benign ESFT infiltrating into the perirenal inferior vena cava. Together with extrauterine leiomyomas, ESFTs should also be considered as a differential diagnosis for the rare benign lesions invading the inferior vena cava.  相似文献   
6.
Bronchiectasis is a chronic debilitating condition characterized by abnormal dilated thick-walled bronchi. To investigate humoral immune function in bronchiectatic patients, this study was performed. Forty patients with established diagnosis of bronchiectasis, who were referred from two tertiary care pulmonology centers in Tehran, were investigated in this study. Immunoglobulin isotypes concentrations and IgG-subclasses were measured by nephelometry and enzyme-linked immunosorbent assay (ELISA) methods, respectively. All patients received unconjugated pneumococcal vaccine, and blood samples were taken before and 21 days after vaccination. Specific antibodies against whole pneumococcal antigens were measured using the ELISA method. Fifteen (37.5%) out of 40 patients were diagnosed to have defects in antibody mediated immunity including 5 (12.5%) patients with immunoglobulin class deficiency (2 with common variable immunodeficiency and 3 with IgA deficiency), 3 (7.5%) with IgG subclass deficiency and 7 (17.5%) patients had Specific antibody deficiency (SAD) against polysaccharide antigen despite normal levels of serum immunoglobulins and IgG subclasses. Our study along with several other studies confirmed that all patients with bronchiectasis should undergo thorough immunological evaluation in order to identify the presence of the underlying immunologic defect. This evaluation should include serum immunoglobulins, IgG subclasses concentrations and also determination of serum antibodies against pneumococcal antigens. Early diagnosis and appropriate treatment will prevent the subsequent complications and improve quality of life of affected individuals.  相似文献   
7.
8.
ABSTRACT. Free carnitine was significantly (p<0.001) reduced both in the ketotic (29.7±3.4 nmol/ml) and in the ketoacidotic (24.6±1.4 nmol/ml) groups when compared to controls (50.0±2.4 nmol/ml). At the same time, acylcarnitine values in the ketotic (21.2±2.4 nmol/ml) and ketoacidotic (25.4±2.3 nmol/ml) groups were significantly above the control value (4.71±0.6 nmol/ml). There was no significant difference between the two ketotic groups in carnitine derivatives. The abnormal distribution of plasma free and acylcarnitines could be reversed by insulin treatment. There was an inverse correlation between ketone body levels and free carnitine in the ketotic (r =-0.71, p<0.02) and ketoacidotic group (r =-0.71, p<0.05). However, there was no correlation between ketone bodies and acylcarnitine and between free carnitine and acylcarnitines. We concluded that the increased acylation was only partly responsible for the reduction of free carnitine in diabetic ketosis.  相似文献   
9.
Primary osteogenic sarcoma of the skull is an exceedingly rare condition. An adult male patient is described, who had a painless swelling in the right forehead that had rapidly enlarged in the previous 6 months. Radiological investigations showed a large destructive mass lesion involving the right side of the frontal bone with extension into the frontal sinus, causing marked extradural compression of brain parenchyma. Histopathological examination confirmed the lesion to be primary osteogenic sarcoma.  相似文献   
10.
The oxidation chemistry and biochemistry of the serotonergic neurotoxin 5,7-dihydroxytryptamine (1) has been studied under anaerobic and aerobic conditions in aqueous solution at physiological pH. Under anaerobic conditions, one-electron oxidants (ferricytochrome c, peroxidase/H2O2, ceruloplasmin, Cu2+) generate a radical intermediate. Dimerization of the C(6)-centered resonance form of this radical followed by secondary oxidations yields 3-(2-aminoethyl)-6-[3-(2-aminoethyl)-1,7-dihydro- 5-hydroxy-7-oxo-6H-indol-6-ylidene]-1-H-indole-5,7(4H,6H)-dione. Under aerobic conditions, molecular O2 attacks the C(4)-centered 1 radical to yield a hydroperoxy radical which decomposes to 5-hydroxytryptamine-4,7-dione (2). Autoxidation of 1 proceeds by primary attack by molecular O2 on a C(4)-centered carbanion to form a superoxide-radical complex. This rearranges to a C(4)-centered hydroperoxide which decomposes to 2. A C(6)-centered carbanion of 1 combines with 2 to give, ultimately, 6,6'-bi-5-hydroxytryptamine-4,7-dione (3). Trace concentrations of transition metal ions (Fe3+, Fe2+, Cu2+, Mn2+) catalyze the autoxidation of 1 by catalytic cycles in which a hydroperoxide intermediate plays key roles. A byproduct of the transition metal-catalyzed oxidation of 1 is superoxide, O2-. Because of its enormous basicity O2- facilitates deprotonation of 1. The C(4)-centered carbanion so produced is oxidized by molecular O2 or by the hydroperoxy radical (HO2) to give radical intermediates and thence 2 and 3. Mechanistic pathways leading to the various products of oxidation of 1 are proposed and the potential roles of oxidation reactions of the indolamine are related to its neurodegenerative properties.  相似文献   
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