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61.
A 61-year-old male was hospitalized for subarachnoid hemorrhage. Cerebral angiography revealed a small left vertebral-posterior inferior cerebellar artery aneurysm, 5 mm to the right of the midline and in the lower third level of the clivus--the so-called "no man's land." It was felt that surgery through the lateral suboccipital approach would likely result in neurological deficits, since the aneurysm would be obscured by the tortuous parent artery or the basilar artery. Therefore, the transoral transclival approach was undertaken and the aneurysm was successfully obliterated. Postoperatively, the patient developed transient right hemiparesis and mild meningitis without evidence of liquorrhea, but fully recovered with conservative management. Certain specific sites of aneurysms, as well as excessive tortuosity of the parent artery, are considered to be indications for the transoral transclival approach. Meningitis is the most worrisome complication of this approach, and mortality is high. Effective preventative measures, which were taken in this case, include tight closure of the dura mater and the pharyngeal mucous membrane, use of the smallest possible clip, and continuous cerebrospinal fluid drainage.  相似文献   
62.
Key words  intractable pain - celiac plexus neurolysis - ultrasonography  相似文献   
63.
Collapsin response mediating protein-2 (CRMP2) has been identified as an intracellular protein mediating Semaphorin3A (Sema3A), a repulsive guidance molecule. In this study, we demonstrate that cyclin-dependent kinase 5 (Cdk5) and glycogen synthase kinase 3beta (GSK3beta) plays a critical role in Sema3A signalling. In In vitro kinase assay, Cdk5 phosphorylated CRMP2 at Ser522, while GSK3beta did not induce any phosphorylation of CRMP2. Phosphorylation by GSK3beta was exclusively observed in Cdk5-phosphorylated CRMP2, but barely in CRMP2T509A. These results indicate that Cdk5 primarily phosphorylates CRMP2 at Ser522 and GSK3beta secondarily phosphorylates at Thr509. The dual-phosphorylated CRMP2, but not non-phosphorylated or single-phosphorylated CRMP2, is recognized with the antibody 3F4, which is highly reactive with the neurofibrillary tangles of Alzheimer's disease. 3F4 recognized the CRMP2 in the wild-type but not cdk5-/- mouse embryonic brain lysates. The phosphorylation of CRMP2 at Ser522 caused reduction of its affinity to tubulin. In dorsal root ganglion neurones, Sema3A stimulation enhanced the levels of the phosphorylated form of CRMP2 detected by 3F4. Over-expression of CRMP2 mutant substituting either Ser522 or Thr509 to Ala attenuates Sema3A-induced growth cone collapse response. These results suggest that the sequential phosphorylation of CRMP is an important process of Sema3A signalling and the same mechanism may have some relevance to the pathological aggregation of the microtubule-associated proteins.  相似文献   
64.
Amyloid enhancing factor (AEF) was extracted from spleens of mice that had received amyloidogenic stimulation. Sephacryl S 300 gel filtration of the crude AEF yielded five fractions, among which strong AEF activity was present in the first peak (Fl), and confirmed by an amyloid induction experiment. An anti AEF antiserum was obtained from a rabbit by immunization with Fl. This antibody reacted strongly with splenic polymorphonuclear leukocytes (PML) from mice given amyloidogenic stimulation, and weakly with those from normal untreated mice. Isoelectric focusing (IEF) analysis of both Fl and sera from mice given amyloidogenic stimulation was performed. A single band was observed on IEF analysis of Fl, whereas many bands were seen on IEF analysis of the sera. After the substances in the gel had been transferred to nitrocellulose membranes by capillary blotting, the membranes were made to react with the anti-AEF antiserum. The results suggested that AEF is a high molecular-weight substance derived from PML and increases in the serum at the time of, or shortly prior to, amyloid deposition in the spleen. Acta Pathol Jpn 39: 349∼355, 1989.  相似文献   
65.
We used proteins in rat lung lavage fluid to successfully produce an antiserum against Clara cell secretory products. When used with the immunoperoxidase method, the antiserum specifically stained cells of the bronchiolar lining, which are morphologically consistent with Clara cells, as well as a few columnar cells in the bronchial and tracheal mucosa. B-5-fixed lung tissue furthermore demonstrated the immunoreactive layer over the bronchiolar epithelium. The alveolar and bronchial lining layers, on the other hand, were not immunoreactive, although a trace of granular immunoreactivity was seen in the latter. It was suggested that Clara cells produce and secrete some proteinaceous materials, which are mainly localized in the bronchiolar area after secretion and are seldom transferred into the alveolar lining layer. Our antibody cross-reacted with the Clara cells of mice, but not with those of hamsters, guinea pigs, rabbits, dogs, cats, monkeys, and man. The high degree of specificity of this antisera to Clara cells in formalin-fixed materials should make it a valuable tool for identifying Clara cell change in non-neoplastic lung pathology and in obtaining some insights into cell origin in neoplastic diseases.  相似文献   
66.
The effects of chronic administration of phenytoin, a common anticonvulsive drug, on immune responses were studied in mice. Anti-keyhole limpet haemocyanin (KLH) IgE antibody response after KLH-immunization was enhanced in phenytoin-treated mice. Proliferative responses of spleen cells induced with KLH, concanavalin A (ConA), lipopolysaccharide and anti-CD3 antibody were reduced in phenytoin-treated mice. Accessory function of spleen adherent cells on ConA-induced T cell proliferative response was reduced in phenytoin-treated mice. KLH-induced IL-4 production of spleen cells was enhanced, while IFN-gamma production was reduced in phenytoin-treated mice. In addition, production of IL-1 alpha, but not IL-6 and IL-12 by spleen adherent cells from phenytoin-treated mice was reduced. Natural killer cell activity was reduced in phenytoin-treated mice. These results suggest that phenytoin treatment preferentially induces a Th2 type response. We also observed that plasma ACTH and corticosterone levels were increased in phenytoin-treated mice, and speculated that phenytoin might act directly and indirectly, through HPA axis activation, on the immune system to modulate Th1/Th2 balance.  相似文献   
67.
Effects of dietary iodine on chemical induction of thyroid carcinoma   总被引:1,自引:0,他引:1  
Effects of dietary iodine on the induction of thyroid carcinoma using N-nitrosobis(2-hydroxypropyl)amine (BHP) were studied. Male Wistar rats were fed with an iodine-adequate diet (IAD group), an iodine-rich diet (IRD group) and an iodine-deficient diet (IDD group), respectively, until the time of sacrifice. From the 2nd experimental month, animals were injected with BHP once a week for 10 weeks. In the IAD and IRD groups, benign nodules and papillary carcinoma were found. The incidence of rats with benign nodules was 100% in both groups and animals with papillary carcinoma in the IAD and IRD groups comprised 33% and 29%, respectively. The area of the thyroid gland occupied by nodular lesions was much narrower in the IRD group than in the IAD group. In the IDD group, the thyroid showed marked enlargement due to multiple nodular proliferation of follicle cells. The incidence of rats with carcinoma was 100%, and not only papillary but also follicular carcinoma and one pulmonary metastasis were found. As the iodine content of the diet decreased, the nodular lesions increased in width and number, and the incidence of carcinoma in rats became higher. These effects of dietary iodine are probably related to the goitrogenic and/or promoting effects of TSH.  相似文献   
68.
Agarose for a bioartificial pancreas.   总被引:8,自引:0,他引:8  
Islets were encapsulated into 5% concentration agarose microbeads. The effect of microencapsulation on islet allograft survivals was determined using a streptozotocin-induced diabetic (STZ) mouse and a nonobese diabetic (NOD) mouse as recipients. All five STZ BALB/c mice receiving microencapsulated islets (C57BL/6) maintained normoglycemia indefinitely. When NOD mice were used as recipients of the bioartificial pancreas, four of five grafts (islets from C3H/He) functioned for more than 80 d. Two of five NOD mice maintained normoglycemia until animals were sacrificed at 102 and 192 postoperative d. Microbeads made of commercially available agarose can effectively prolong alloislets functioning in the STZ-diabetic mouse and even in the NOD mouse (animal model of human type I diabetes) without the use of any immunosuppressive drug.  相似文献   
69.
The genetic polymorphism of orosomucoid (ORM) and alpha-2-HS-glycoprotein (AHSG) were studied in Thai, Sri Lankan and Paraguayan populations using isoelectric focusing. Gene frequencies in these populations were compared with those in other populations. Four new ORM variants were detected:ORM1 * 15 in Thai,ORM1 * 16 in Paraguayan,ORM2 * 21 andORM2 * 22 in Sri Lankan.  相似文献   
70.
Guinea pig IgE antibodies to ovalbumin or mite were measured by enzyme-linked immunosorbent assay (ELISA), and the levels of IgE antibodies to mite were compared with titers of passive cutaneous anaphylaxis (PCA). The results of ELISA were highly reproducible when the assays were done in the same microtiter plate and on the same day. The levels of IgE antibodies to mite determined by ELISA correlated well with the PCA titers (n = 29, r = 0.70, p less than 0.001). The measurement of IgE antibodies by ELISA saved much time in comparison with PCA which needs at least 7 days for getting results.  相似文献   
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