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741.
742.
743.
Sixteen young women with hyperprolactinaemia and normal or equivocal sella in radiographs underwent computed tomography using a Siemens Somatom II. In all but one case an abnormality was found. The sella was full in seven and partially empty in nine. A tumour was visible in six of the full and in four of the partially empty sellae. All but one of the 10 tumours was unilateral, and in seven the pituitary stalk was deviated away from the tumour. After administration of intravenous contrast (Urografin) four tumours showed diffuse enhancement, four ring enhancement, and two enhanced less than adjacent normal pituitary tissue. Two of the tumours have been subsequently shown histologically to be prolactinomas. Prolactin response to thyrotrophin-releasing hormone predicted a tumour in seven out of eight with visible tumours but also in three out of four without visible tumours; using metoclopramide, a tumour was predicted in six out of seven with tumours, but again in three out of four without visible tumours. Such results question the value of dynamic tests for the discrimination of tumours. We conclude that practically all women with sustained hyperprolactinaemia and a normal or equivocal sella radiologically have pituitary disease.  相似文献   
744.
NB 《网络与信息》2007,21(2):32-33
网友提问酷睿2T5X X X的技术参数?T5600:2M B二级缓存,1.83G H z主频,667M H z前端总线,支持虚拟化技术;T5500:2M B二级缓存,1.66G H z主频,667M H z前端总线,不支持虚拟化技术;另外,最新推出的T5200是降频“缩水”版本,2M B二级缓存,1.6G H z主频,533M H z前端总线,不支持虚拟  相似文献   
745.
Cell-to-cell communication was characterized in prefusion chick embryo myoblast cultures, and it was determined that the prefusion myoblasts can interact via gap junctions, ionic coupling, and metabolic coupling. The biological relevance of this communication was supported by the detection of gap junctions between myoblasts in embryonic muscle. Communication was also examined in fusion-arrested cultures to determine its potential relationship to fusion competency. In cultures that were fusion arrested by treatment with either 1.8 mM ethyleneglycolbis-(beta-aminoethyl ether)N,N'-tetraacetic acid (EGTA), 3.3 X 10(-6) M 5-bromodeoxyuridine (BUdR), or 1 microgram/ml cycloheximide (CHX), both gap junctions and ionic coupling were present. Therefore, it is possible to conclude that cell communication is not a sufficient property by itself, to generate fusion between myob-asts. The potential role of communication in myogenesis is discusssed with respect to these observations.  相似文献   
746.
The ciliary activity of Ctenophore bolinopsis is inhibited by decreasing concentration of Mg2+ and increasing concentration of Ca2+ in the medium. The same changes in Mg2+ and Ca2+ concentration trigger muscle contractions and bioluminescence. Co2+ arrests the cilia beating in the rectangular position. An increase in Mg2+ concentration or decrease in Ca2+ concentration switch off the nervous inhibitory mechanisms of ciliary activity, suppress muscle contractions and bioluminescence. Ni2+ produces a similar effect, but the ciliary heating is only slightly accelerated, by the contrast to the effect of increased Mg2+ concentration. A Cl-free medium Mn2+ and tetrodotoxin in commonly used concentrations are of no effect on the systems studied. Experiments involving changes in K+ concentrations and administration of tetraethylammonium suggest that the resting potential in the examined cells may be due to K+ as the most permeant ion, and that K+-channels in the cell membrane may be voltage--controlled. The proposal about "biionic" (Ca2+/Mg2+) bioelectric control of a number of intracellular reactions is discussed.  相似文献   
747.
The effects of a new series of glutarimide compounds have been studied in acetylcholine induced auricular fibrillation in anaesthetized cats and epinephrine induced ventricular arrhythmmias in conscious pigeons. Some of the compounds showed varying degree of protective action against experimental arrhythmias. However these compounds were found to be less potent than quinidine. The mechanism of antiarrhythmic action has been discussed.  相似文献   
748.
The 5-year survival rates of 540 patients with carcinoma of the cervix and 186 with carcinoma of the corpus uteri were assessed in relation to the modal DNA values of the tumors. Patients with squamous cell cervical carcinomas had more favorable prognoses if the modes were near-triploid or hypotetraploid; however, these high-ploidy tumors included more stage III cases than did the tumors with near-diploid modes. Patients with near-diploid endometrial carcinomas has considerably more favorable prognosis than did patients with the minority of tumors at this site, who had high modes; this prognostic difference was only partly related to a higher proportion of poorly differentiated tumors in the high-ploidy group since, among the poorly differentiated tumors, individuals with near-diploid modes again had significantly better prognoses than those with high modes.  相似文献   
749.
NB 《网络与信息》2008,(5):52-53
眼下买笔记本的人是越来越多,这其中也不乏第一次接触笔记本电脑的新手和连电脑根本玩不转的菜鸟们.  相似文献   
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