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1.
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.
Familial Sneddon's syndrome 总被引:4,自引:0,他引:4
Alexander Lossos Tamir Ben-Hur Ziva Ben-Nariah Claes Enk Moshe Gomori Dov Soffer 《Journal of neurology》1995,242(3):164-168
We report the familial occurrence and apparent autosomal dominant inheritance of Sneddon's syndrome with variable clinical expression. The proband, a 40-year-old woman, presented with livedo reticularis and progressive neurological deterioration following a stroke. The diagnosis was confirmed by cerebral angiogram and skin biopsy, both showing the characteristic findings. Two of the patient's sisters were reported to have been similarly affected in the past. Her mother, two additional siblings and five of her seven children exhibited various vasospastic skin phenomena. Familial aggregation of this disorder may be common and a genetic basis may be involved in its pathogenesis. 相似文献
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新生儿和儿童乙肝免疫 总被引:3,自引:1,他引:2
陈仕珠 《世界华人消化杂志》2006,14(27):2708-2712
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
6.
This study was done to evaluate the surgical results and the impact on fertility potential of 3 methods of varicocele treatment. Consecutive varicocele patients with primary or secondary infertility were randomly assigned to 3 treatment groups. Of the patients 36 underwent percutaneous embolization, 55 high ligation of the internal spermatic vein and 28 transinguinal simultaneous ligation of the internal and external spermatic veins. The transinguinal ligation proved to be safe. There was no difference in pregnancy rates but the seminal variables showed a slight improvement with statistical significance only in the 2 open surgical methods. There were no surgical failures in the transinguinal group as opposed to the other 2 techniques. Transinguinal ligation of the internal and external spermatic veins may be recommended as the primary treatment for varicocele. This technique also seems to be the procedure of choice when repeat intervention is required for failure of high ligation or embolization. 相似文献
7.
I. Steiner G. Feir D. Soffer A. B. Pleet O. Abramsky 《Acta neurologica Scandinavica》1988,77(2):152-157
The causes and clinical features of chronic progressive myelopathy (CPM) were evaluated in a retrospective study of 107 patients. A special emphasis was put on those in whom no underlying cause for the myelopathy could be determined. Of 76 such, 39 (51%) had oligoclonal immunoglobulins (Ig) in the CSF and were therefore considered as possible MS, while the remainder, without oligoclonal Ig, were designated "myelopathy of unknown origin" (MUO). Our "possible MS" group was similar clinically to reported series of proven spinal MS, and it seems therefore, that the presence of oligoclonal Ig permits the recognition of a group of patients with myelopathy who might be at a greater risk for MS. Patients with MUO differed from possible MS patients in several clinical characteristics, but most significantly in disease course and levels of functional disability which were more benign in the former. Myelopathy in possible MS patients was also of a primary pyramidal and asymmetrical nature. It is therefore suggested that the segregation of patients with CPM of undetermined origin into 2 separate groups based on the presence or absence of oligoclonal Ig might be of prognostic significance. 相似文献
8.
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.相似文献
9.
Francesca Levi-Schaffer Naomi Riesel Dov Soffer Oded Abramsky Talma Brenner 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1991,15(2):173-184
The number and functional reactivity of peritoneal mast cells (MCs) were evaluated in rats with experimental allergic encephalomyelitis (EAE). Cells were counted following staining with toluidine blue and activation was measured by B-hexosaminidase (B-hex) release. The number of detectable MCs and their capacity to release B-hex decreased significantly by 40 and 65%, respectively, as compared with normal controls just prior to the onset of clinical signs. These values returned to normal on clinical recovery. Preliminary data on MC counts performed on histological sections of rat brains with EAE suggested a similar pattern of response, i.e., an early decrease prior to disease onset with subsequent normalization on recovery. In an attempt to modify the course of EAE, rats were treated with the MC stabilizing agent nedocromil or with the MC activating agent, compound 48/80. Nedocromil induced a slight delay in the onset of EAE, but only when administered at the time of EAE induction. Compound 48/80 did not seem to affect the clinical course of the disease. Our results suggest that MCs are involved in the pathogenesis of EAE and may contribute to the induction of the disease rather than to the effector phase and its clinical expression. 相似文献
10.
Shevach Friedler M.D. Arieh Raziel M.D. Yigal Soffer M.D. Deborah Strassburger Ph.D. Dafna Komarovsky B.Sc. Raphael Ron-El M.D. 《Fertility and sterility》1997,68(5):892-897
Objective: To compare the outcome of intracytoplasmic sperm injection (ICSI) with fresh and frozen-thawed testicular spermatozoa in patients with nonobstructive azoospermia.Design: Retrospective analysis of consecutive ICSI cycles.Setting: In Vitro Fertilization Unit, Assaf Harofeh Medical Center.Patient(s): Eighteen with nonobstructive azoospermia in whom testicular sperm was found after testicular sperm extraction.Intervention(s): Testicular sperm retrieval, cryopreservation, and ICSI with fresh or frozenthawed testicular spermatozoa.Main Outcome Measure(s): Two-pronuclear fertilization; embryo cleavage rates, mean number of embryos transferred per cycle, and their relative quality, embryo implantation, clinical pregnancy, and ongoing pregnancy rates (PRs) per ET.Result(s): No statistically significant differences were noted in all parameters examined between ICSI cycles with fresh or cryopreserved testicular spermatozoa from the same nine patients and comparing all ICSI cycles performed; with fresh (25 cycles) and thawed (14 cycles) testicular spermatozoa, respectively: two-pronuclear fertilization, 47% versus 44%; embryo cleavage rates, 94% versus 89%; implantation rates, 9% versus 11%; and clinical PR, 26% versus 27%. The delivery or ongoing PR using fresh sperm was better (21% versus 9%), but the difference did not reach statistical significance. The cumulative clinical PRs and ongoing PRs per testicular sperm extraction procedure were 36% and 24%, respectively.Conclusion(s): Testicular sperm cryopreservation using a simple freezing protocol is promising in patients with nonobstructive azoospermia augmenting the overall success achieved after surgical sperm retrieval. (Fertility Sterility 1997;68:892-7. C 1997 by American Society for Reproductive Medicine.) 相似文献