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91.
In a recent series of studies, we demonstrated that stress in humans and animals, with resultant sympathetic nerve strain, induces severe granulocytosis, because granulocytes carry adrenergic receptors on the surface. Because activated granulocytes produce free radicals and superoxides, they sometimes induce tissue damage if the stress is too strong or continuous. Human neonates are also known to show high levels of granulocytes in the peripheral blood. In this study, we investigated whether such neonatal granulocytosis are a stress-associated response at birth. Both human and mouse materials, before and after birth, were used. The number of leukocytes in the blood, as well as some other factors in the serum, were measured. Although levels of granulocytes were found to be low in fetal humans and mice, they increased sharply after birth. In parallel with this postpartal granulocytosis, transaminases in sera increased transiently. In reference to results of a transient elevation in the levels of catecholamines at birth in mice, all these phenomena resemble stress-associated responses. Indeed, fatty liver and hematopoietic destruction in the liver were also observed in mice and humans. At this time, the production of inducible nitric oxide synthase (iNOS) by granulocytes in the liver was evident. These results suggest that neonatal granulocytosis is a postpartum event which results from various stresses (e.g., oxygen stress) at birth. This event may be responsible for such well-known neonatal phenomena as the termination of fetal hematopoiesis in the liver and as neonatal jaundice.  相似文献   
92.
We performed an anterior spinal fusion using a vascularized fibular bone graft combined with posterior fusion for a patient with severe cervical kyphosis due to neurofibromatosis. The kyphosis was corrected from 85 degrees preoperatively to 38 degrees postoperatively. A vascularized fibular bone graft is a useful surgical procedure in selected patients to obtain successful bony union.  相似文献   
93.
A retrospective study of 155 patients with submucosal gastric carcinoma compared the clinicopathologic features with mucosal and muscularis proprial gastric carcinoma. Fifty-seven percent of the patients presented with gastrointestinal symptoms, whereas 36.1% had been detected by mass screening. The incidence of curative resection, lymph node metastasis, and complications were 96.1, 20.6, and 14.8%, respectively. Two patients died of sepsis and pulmonary infarction 30 days post-operatively. Five patients died of recurrent gastric cancer 1-5 years postresection. The overall 5-year survival rate was 90.2%. Recurrence patterns, histologic type, lymph node metastasis, lymphatic and venous infiltration, and growth pattern were similar to those of muscularis proprial carcinoma rather than mucosal carcinoma. Therefore, curative gastrectomy with extended lymphadenectomy (D2) may be feasible for submucosal carcinoma of the stomach.  相似文献   
94.
95.
High mobility bottom-gate poly-Si thin film transistors (TFTs) have been successfully fabricated on a hard glass substrate using XeCl excimer laser annealing and ion doping techniques. The authors used an a-Si:H film which is deposited by a plasma-enhanced chemical vapor deposition (PECVD) as a precursor film, and then they crystallized the a-Si film by XeCl excimer laser annealing. The maximum field effect mobility and grain size obtained were 200 cm2/V-s (n-channel), and 250 nm, respectively. The poly-Si TFTs showed excellent transfer characteristics, and an ON/OFF current ratio of over 106 was obtained. Successful control of the threshold voltage within 4 V using an ion doping technique is also demonstrated  相似文献   
96.
Abstract: This paper proposes a method for formulation and quantification of human subjective evaluations and uncertain numerical values by using multiple hyperplanes based on the results of questionnaires distributed to structural designers that are composed of four questions about structural design and planning, i.e., ( Q 1) structural damage , ( Q 2) structural economy in a macroscopic sense , ( Q 3) structural safety, and ( Q 4) opening patterns in facade. In this paper, some hyperplanes in multidimensional spaces are used as a method to identify fuzzy relations (states) in intelligent fuzzy networks for seismic structural planning. A genetic algorithm is employed as a search method for optimal formulations and is proved to be very effective as a method for such an identification.  相似文献   
97.
Mutations in the presenilin genes PS1 and PS2 cause the most common form of early-onset familial Alzheimer's disease. The influence of PS1 mutations on the generation of endogenous intracellular amyloid beta-protein (A beta) species was assessed using a highly sensitive immunoblotting technique with inducible mouse neuroblastoma (Neuro 2a) cell lines expressing the human wild-type (wt) or mutated PS1 (M146L or delta exon 10). The induction of mutated PS1 increased the intracellular levels of two distinct A beta species ending at residue 42 that were likely to be A beta1-42 and its N-terminally truncated variant(s) A beta x-42. The induction of mutated PS1 resulted in a higher level of intracellular A beta1-42 than of intracellular A beta x-42, whereas extracellular levels of A beta1-42 and A beta x-42 were increased proportionally. In addition, the intracellular generation of these A beta42 species in wt and mutated PS1-induced cells was completely blocked by brefeldin A, whereas it exhibited differential sensitivities to monensin: the increased accumulation of intracellular A beta x-42 versus inhibition of intracellular A beta1-42 generation. These data strongly suggest that A beta x-42 is generated in a proximal Golgi, whereas A beta1-42 is generated in a distal Golgi and/or a post-Golgi compartment. Thus, it appears that PS1 mutations enhance the degree of 42-specific gamma-secretase cleavage that occurs in the normal beta-amyloid precursor protein processing pathway (a) in the endoplasmic reticulum or the early Golgi apparatus prior to beta-secretase cleavage or (b) in the distinct sites where A beta x-42 and A beta1-42 are generated.  相似文献   
98.
The vertebrate opsins have been classified into four major phylogenetic groups. One of them, a short wavelength-sensitive (SWS) opsin group, is further divided into two subgroups, SWS-I and SWS-II, having the wavelengths of maximal absorption of about 420 and 450 nm, respectively. Here we report the DNA sequences of the SWS-I and SWS-II genes from the lizard Anolis carolinensis. The shorter wavelengths of absorption by the two SWS subgroup opsins seem to be achieved by different sets of amino acid replacements in the transmembrane regions.  相似文献   
99.
Peptidylarginine deiminase (PAD) is the enzyme responsible for converting protein-bound arginine residues to citrulline. It has recently been shown that a number of epidermal proteins, including filaggrin, trichohyalin, and keratins, are deiminated by the action of PAD, suggesting a possible role for protein deimination during the final stages of epidermal differentiation. We report here a novel PAD substrate found during the course of identifying deiminated proteins in cultured rat epidermal keratinocytes. We found that a 70-kD protein localized to the periphery of the nucleus was preferentially deiminated after ionomycin treatment in the presence of 2 mM calcium and was associated with apoptotic events in these cells. Furthermore, we discovered that the deimination of nuclear protein could be induced by transfection of a PAD cDNA into rat epidermal keratinocytes. These data suggest that PAD may act on the 70-kD nuclear protein to induce disassembly of the nuclear lamina and promote apoptosis during terminal epidermal differentiation.  相似文献   
100.
In the reconstructive procedure of the anterior cruciate ligament (ACL), the relationship was investigated between the orientation of the drill holes from the isometric points and the deformity in the ligament graft. We first investigated, by numerical analysis, the optimal orientation of the drill holes for minimal deformation. Secondly, we experimentally by using eight fresh cadaveric knees, measured the relationship between the orientation of the drill holes and the bending angle in the grafts. The optimal orientation of the drill hole in the femur was found to be tilted 20 degrees laterally in the coronal plane and 23 degrees anteriorly in the sagittal plane. In the tibia, the drill hole should be directed 24 degrees medially and 50 degrees anteriorly from the isometric point. The numerically analysed bending angle corresponded well to the results from the experimental study. The deformation in the graft on the femoral side was larger than that on the tibial side. Therefore, the orientation of the femoral drill hole was concluded to be more important than the orientation of the tibial drill hole.  相似文献   
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