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11.
Giant or large intracranial aneurysms are the vascular neurosurgeon's greatest challenge. At our department, we have treated one hundred and thirty nine patients with giant or large intracranial aneurysms between 1975 and 2001. These included 37 partially thrombosed giant aneurysms. 75 aneurysms were giant (> 2.5 cm) and 64 were large aneurysms (2-2.5 cm). Three-dimensional computed tomography angiograms were performed in patients besides MRI angiography and digital subtraction angiography. These were found to be very valuable in the preoperative assessment of surgical anatomy of the aneurysm with respect to the branch arteries and perforators origin besides knowing the relations to the skull base. With our experience in surgical treatment of these 139 cases, we find that the basic technique is trapping and evacuation and not just clipping of the aneurysm neck but also reconstruction of the artery bearing the aneurysm, especially with wide-necked aneurysms. Use of multiple clipping, tandem clipping or dome clipping as per the intraoperative situation, is very helpful in dealing with giant aneurysms as also is the use of different types of clips like fenestrated clip with straight clip (combination clipping), booster clip, dome clips etc. While selecting surgical strategy for partially thrombosed giant aneurysm, securing the neck is most important. If the neck is too narrow to reconstruct, aneurysmectomy with anastomosis is one of the surgical strategies. An extracranial intracranial bypass should be considered in cases where clipping or parent artery ligation is expected to be associated with compromise of cerebral circulation.  相似文献   
12.
Between 1978 and 1988, 15 patients with gallbladder cancer and 2 patients with bile duct cancer were seen among 49 patients with anomalous union of the pancreaticobiliary ductal system. Radiographic findings revealed two types of this anomalous condition: one in which the pancreatic duct entered the common bile duct (type 1) and one in which the common bile duct entered the pancreatic duct (type 2). In gallbladder cancer, the common bile duct presented no dilatation, or in some patients, mild dilatation, and type-1 anomalous union was frequently found among these patients. In contrast, the two patients with bile duct cancer had cystic dilatation of the common bile duct and type-2 anomalous union. The bile amylase level, which was determined in seven patients, was extremely high in all the patients. Histopathologically, the tumors in most patients showed papillary to papillo-tubular proliferation in the mucosal layer while atypical epithelial hyperplasia was noted in the vicinity of the tumor area. These findings suggest that this congenital anomaly in both ducts results in a loss of the normal sphincteric mechanism of the duodenal papilla, and that chronic relapsing cholecystitis or cholangitis, caused by the reflux of pancreatic juice into the biliary tract, can induced progressive changes to atypical epithelial hyperplasia which may develop into carcinoma.  相似文献   
13.
Abstract: Two autopsied female sibling cases of sudanophilic leukodystrophy are reported. Case A and case B were the second and third of seven siblings, and a sister and a brother died from severe progressive neurological disease with similar symptoms. Consanguineous marriages were noted in the family of both cases through the past three generations. Case A gradually developed intellectual deterioration and tetraplegia at the age of 29, progressed to akinetic mutism within one year and thereafter survived for 14 years. Neuropathologically, a severe atrophy and degeneration were noted in the white matter of the whole cerebrum, sparing the subcortical U-fibers. Myelin and axons were severely damaged with peripheral astrocytic gliosis. Case B developed similar clinical symptoms at the age of 20 and survived for 7 years in the state of akinetic mutism. Similar postmortem findings as those of case A were found in the white matter of the cerebrum with formation of sudanophilic breakdown products and with thick fibrillary gliosis. The pyramidal tract was completely degenerated. There was no accumulation of abnormal lipid in the brains of both cases.  相似文献   
14.
Between January 1993 and December 2001, we employed percutaneous cardiopulmonary support (PCPS) in 35 patients. PCPS was used for postcardiotomy in 25 of these patients who could not be weaned from cardiopulmonary bypass (CPB) because of severe cardiogenic shock. In the other 10 patients, PCPS was used for a non-surgical disease. Twenty-nine patients (82.9%) were weaned from PCPS, and 28 (80.0%) survived. The other 7 patients (20.0%) died due to postoperative complications. The causes of death were multiple organ failure (MOF) due to wound bleeding, low cardiac output syndrome (LOS), myonephropathic metabolic syndrome (MNMS) with severe lower limbs ischemia, cerebrovascular accident (CVA), and sepsis. The first cause for the complications was postoperative sustained severe heart failure. To improve the survival rate, it was necessary to prevent bleeding and begin PCPS at an earlier stage.  相似文献   
15.
Quality control of laboratory testings has been markedly improved. However, the importance of preanalytical quality control seems to have been poorly recognized by most medical staff members. In order to improve the present preanalytical situation, a round table discussion on sampling and transportation was held together by doctors, nurses and laboratory staff to know the present situation and to recognize the current problems. It was stressed that better communication among medical staffs and also between medical staff and patients are essential to obtain more precise data.  相似文献   
16.
Summary A human glioma cell line (YKG1), which was positively identified for glial fibrillary acidic (GFA) and S-100 proteins, was established from a surgical specimen of a patient with glioblastoma. Chromosome analysis of the cells revealed a homogeneously staining region (HSR) on a marker chromosome. The assay for transforming growth factors (TGFs) in the conditioned medium of the cell line revealed that it contained high levels of - and -type TGFs, which might regulate the growth of glioblastoma and influence on the peritumoral tissues.  相似文献   
17.
Primrose syndrome is a congenital malformation syndrome characterized by intellectual disability, developmental delay, progressive muscle wasting, and ear lobe calcification. Mutations in the ZBTB20 gene have been established as being accountable for this syndrome. In this study, a novel de novo ZBTB20 mutation, NM_001164342.2:c.1945C>T (p.Leu649Phe), has been identified through whole exome sequencing (WES) in a female patient presenting a typical Primrose phenotype. Because the present patient exhibited recurrent otitis media, detailed immunological examinations were performed in this study and subnormal immunoglobulin levels were firstly identified in a Primrose patient. Anatomical anomaly of the inner ear has never been reported in this patient and WES data did not include any relevant variants causally linked with the immunologic defect. Thus, there is a possibility of a relation between an unclassified immunodeficiency with selective IgG2 deficiency and Primrose syndrome and this may be the reason of recurrent otitis media frequently observed in Primrose patients. Because subnormal levels of IgG2 in this patient might be caused by an unrelated and still uncharacterized genetic cause, further studies are required to prove the causal link between aberrant ZBTB20 function and immunodeficiency.  相似文献   
18.
TCR repertoire in early fetal mouse thymus   总被引:1,自引:0,他引:1  
We investigated the rearrangement and expression of TCR genesin mouse fetal thymus organ culture, a system that avoids subsequententry of hematopoietic precursor cells. The first observablerearranged TCR gene was homogeneous V2-J2, detectable as earlyas fetal day 11 (d11) in the thymic primordla. The productiveTCR was homogeneous V5-J1, first detectable in d13 thymocytes,followed by adult-type TCR (V4 and V7). Sequence analysis ofTCR revealed five types of V-J junctional sequences. In thevery early stage, a homogeneous V-J junction is generated viaa short homology sequence in the coding region (Type I), whilea short homology sequence in the P-nucleotlde rather than thecoding region is used in the following stage (Type II). In thelater embryonic stages, diverse V-J junctions are generatedby well-known mechanisms, such as P-nucleotide (Type III), N-regioninsertion (Type IV) or trimming of the coding ends (Type V).These findings suggest that the generation of homogeneous TCR (V2 and V5) in the early fetal stages is due to the intrinsicrearrangement mechanisms and is in stage specific manner.  相似文献   
19.
Ionic mechanisms and signal transduction underlying noradrenaline (NA)-induced depolarization in single smooth muscle cells of guinea-pig vas deferens were studied. NA caused depolarization followed by action potentials through activation of 1-adrenoceptors. In the presence of nifedipine, no action potential was generated, and the magnitude of the depolarization depended on the concentration of NA (0.1-100 micrometer). NA, through 1-adrenoceptor activation, reduced the magnitude of membrane currents in response to voltage ramp pulses from -90 to -30 mV in a concentration-dependent manner. The reversal potential of the current inhibited by NA changed proportionally to the change in the equilibrium potential of K+, suggesting that NA inhibited K+ channel activity. Treatment of cells with GDPS, an inhibitor of G proteins, or bisindolylmaleimide (BIM), a selective protein kinase C (PKC) inhibitor, prevented the NA inhibition of the currents. Application of 12-O-tetradecanoylphorbol 13-acetate (TPA), an activator of PKC, mimicked the effect of NA. It is suggested that in the smooth muscle of guinea-pig vas deferens, activation of 1-adrenoceptors and the subsequent activation of PKC led to inhibition of K+ currents, which is responsible for the depolarization induced by NA.  相似文献   
20.
We compared two sets of sex and age-specific reference intervals obtained from two large reference populations, one set calculated with data from 700,000 reference individuals by the nonlinear optimizing method of Ohgushi and Shibata and the other set calculated with data from 150,000 reference individuals from Shizuoka prefecture by the revised Hoffmann fitting method. Ten laboratory analytes used for health screening were compared. The sex- and age-specific reference intervals for total cholesterol, fasting blood sugar, uric acid, total protein, and albumin from the two large reference sample groups closely resembled each other, but reference intervals for the enzyme analytes aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and gamma-glutamyl transpeptidase only partly corresponded. Surprisingly, new information came from comparison of the sex- and age-specific reference intervals of alkaline phosphatase: low activities were observed in young females and higher activities were observed in older females. If a reference interval is used that does not take this observation into account, misdiagnosis of hyperthyroidism, which is frequently observed in young women, may result. Sex- and age-specific reference intervals should be used to interpret results of laboratory screening tests.  相似文献   
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