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171.
S. Sunano T. Shimada K. Moriyama K. Shimamura 《Clinical and experimental pharmacology & physiology》1990,17(6):413-425
1. The time courses of the relaxation, induced by removal of extracellular Ca2+, of K-depolarized mesenteric artery preparations from stroke prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto rats (WKY) were compared. 2. The time course of the decline in extracellular Ca2+ was estimated from the time course of the relaxation and the concentration-response curve of K(+)-depolarized preparations to Ca2+. The time course of the decline in the intracellular free Ca2+ concentration was also estimated from the reported relation between Ca2+ concentration and the contraction of skinned vascular smooth muscle. 3. The time course of relaxation was exponential, the curve being made up of three components. The time course was slower in preparations from SHRSP, especially the first component of the relaxation curve. 4. The time courses of the decline in the intracellular and extracellular Ca2+ concentrations were also exponential, being made up of three components and were also slower in the preparation made from SHRSP. 5. The wall and muscle layer of the mesenteric arteries used in the present experiments were significantly thicker in the SHRSP preparations. 6. Calculation of the half relaxation time, based on the diffusion of Ca2+ across the blood vessel wall, suggested that the slower relaxation in preparations from SHRSP is due largely to the thicker muscle layer, although differences in Ca2+ sequestration by the smooth muscle cells may also be involved. 相似文献
172.
During a 9 month period, 50 consecutive children were evaluated by ultrasound to determine the size, location (mesenteric vs para-aortic), number, shape and texture of abdominal lymph nodes in a normal paediatric population. High resolution linear array transducers were used with graded compression. Nodes ranging from 10 to 20 mm were recorded in the majority of subjects. In all cases mesenteric lymph nodes were larger and more numerous than para-aortic nodes. Para-aortic lymph nodes were not seen in isolation. 相似文献
173.
M. Villaplana A. García Ayala M. P. García Hernández B. Agulleiro 《Anatomy and embryology》1996,193(5):441-452
The cell organization of the pituitary gland and the relationship between neurohypophysis and adenohypophysis in the early developmental stages of the gilthead sea bream, Sparus aurata, were studied by electron microscopy. In newly hatched larvae, the pituitary gland was embedded in the ventral floor of the diencephalon and separated from the hypothalamus by a continuous basal lamina. Elongated mesenchymal cells next to the ventral surface were observed. At this stage, there was no neurohypophysis and the adenohypophysis consisted of undifferentiated endocrine cells with small scarce secretory granules and a few stellate cells, with no distinctive zonation. An incipient neurohypophysis was present in 1-day-old larvae. The first evagination of the neurohypophysis into the adenohypophysis were observed in 2-day-old larvae and developed progressively with age, being deeper in the caudal zone. Two regions in the adenohypophysis, one anterior — the presumptive pars distalis — and one posterior — the presumptive pars intermedia — were found in 2-day-old larvae. Three regions (rostral and proximal pars distalis and pars intermedia) were clearly distinguishable in 4-day-old larvae. The ultrastructural features of the pituitary endocrine cells varied during gland differentiation, with the secretory granules gradually increasing in number and size, accompanying organelle development. Nevertheless, even in the oldest larvae studied (65 days), undifferentiated cells similar to those in the earliest stages were observed. The first blood vessels appeared in the neurohypophysis around 16 days after hatching. During early development, the pituitary gland progressively emerged from the ventral floor of the brain. By 16 days, the principal pattern of the pituitary gland architecture appeared to be established. 相似文献
174.
Juhani Trmnen Osmo Tervonen Antero Koivula Juhani Junila Ilkka Suramo 《Journal of magnetic resonance imaging : JMRI》1996,6(5):805-811
The purpose of this study was to explore systematically the effect of the imaging parameters changeable by the user in spin-echo (SE) imaging sequences to minimize image distortion when imaging joint prostheses. A titanium alloy hip joint prosthesis was studied at 1.0 T. The SE imaging parameters were bandwidth/pixel (BW/p), TE, strength of encoding gradients (matrix size), echo train length (ETL), and direction of phase and frequency encoding. The effect of ETL in rapid acquisition relaxation enhanced (RARE) sequences was also evaluated with a turbo-SE sequence using a different ETL with the same TR and an effective TE. It is concluded that an optimized image quality can be achieved in SE imaging by using a high bandwidth/pixel value (at least 130 Hz/pixel), a high resolution matrix (256–512), sequences with multiple refocusing, and a frequency-encoding axis parallel to the long axis of the prosthesis. The degree of distortion is reduced with this optimized technique. 相似文献
175.
Patients'attitudes to rectal drug administration 总被引:2,自引:0,他引:2
One hundred adult patients attending for day case surgery were surveyed by anonymous questionnaire in order to determine their attitudes to rectal drug administration. Fifty four patients did not want an analgesic drug (diclofenac sodium) administered rectally whilst under anaesthesia, all preferring to take it orally if available. Ninety eight patients thought that drugs administered per rectum should always be discussed with them beforehand and a few had very strong feelings about this route of administration. We suggest that prescribers of rectal diclofenac should always discuss it with patients pre-operatively. Whilst many are happy to have suppositories, some young patients are sensitive about this and prefer to take such medication by mouth. 相似文献
176.
第Ⅲ段肝管空肠吻合解除肝门部胆管恶性梗阻 总被引:6,自引:0,他引:6
肝门部胆管恶性梗阻的治疗仍然十分困难。若不解除胆道梗阻,病人很快因肝细胞功能衰竭而死亡。由于肿瘤在肝门部侵润性生长,直接经肝门的手术往往不可能实现。1980~1993年间,我们采用第Ⅲ段肝管空肠吻合术姑息治疗28例肝门部胆管恶性梗阻的黄疸病人。24例为肝门部胆管癌,2例为胆囊癌,2例为胃癌肝门部淋巴结转移。术后19例病人恢复顺利;5例发生并发症,4例病人手术后死亡。24例存活病人中,19例黄疸完全消退3月以上,手术有效率为79%。4例黄疸再次出现,2例因胆管炎需要入院治疗。作者认为:第Ⅲ段肝管空肠吻合术能有效解除不能切除的肝门部恶性肿瘤病人的胆道梗阻。 相似文献
177.
Influence of age on faecal carriage of P-fimbriated Escherichia coli and other gram-negative bacteria in hospitalized neonates 总被引:3,自引:0,他引:3
K. Tullus B. Fryklund B. Berglund G. Kllenius L. G. Burman 《The Journal of hospital infection》1988,11(4):349-356
The aerobic faecal flora of 953 infants aged over 5 days was studied on discharge from 22 neonatal wards in Swedish hospitals. Klebsiella/enterobacter was isolated from 74% of infants and dominated the aerobic gram-negative flora in 19 wards. Escherichia coli was carried by 42% and showed a slight dominance in two wards. Initially klebsiella/enterobacter dominated the flora but became increasingly mixed with and taken over by E. coli, carriage increasing from 21% in infants discharged after 5-7 days to 57% after 3 weeks or later. Among infants with E. coli, P-fimbriated strains were demonstrated in 23% (range 0-67) and were independent of age. Occasional clustering of such strains was observed in 3/22 wards during the study period. It is postulated that the general and local colonization patterns observed reflect differences between individual strains of E. coli and klebsiella in both their capacity for transmission and their persistence in the newborn gut. The role of P-fimbriae in intestinal colonization of neonates by E. coli was, however, not supported. 相似文献
178.
179.
应用同种动脉治疗主动脉根部病变 总被引:4,自引:0,他引:4
报告5例采用同种动脉(HAV)治疗5例主动脉根部病变(主动脉瓣狭窄1例,关闭不全4例)。男3例,女2例;年龄13~47岁。病因为细菌性心内膜炎2例(包括先天主动脉瓣二瓣化畸型1例),Marfan综合征2例,风湿性主动脉瓣关闭不全1例。术中采用同种主动脉全根置换3例(Bentall手术),其中1例用HAV上的二尖瓣前叶加宽主动脉瓣环(Manouguian手术),余2例用自体肺动脉移置主动脉根部,另取同种肺动脉做原位移置(Ross手术)。结果死亡1冽,4例存活,且无并发症发生。术后超声心动图提示主动脉根部良好,无主动脉瓣反流。随访2.5~3.5年疗效满意。 相似文献
180.
Janice F. Munro Debra Haire-Joshu Edwin B. Fisher H. James Wedner 《The Journal of asthma》1996,33(5):313-325
Low-income minority patients from East St. Louis, Illinois, a depressed midwestern urban city, who had visited acute care settings with asthma symptoms, participated in a focus group. Questions were constructed around the Health Belief Model to characterize participants' experiences in receiving asthma care, their confidence in long-term asthma self-management, barriers they perceived to managing their asthma, and recommendations they would make for improving asthma care in their community. Analysis of comments suggests an appreciable understanding of asthma triggers, limited coping behaviors for asthma symptoms, very limited practice of active asthma management, perception of the health care system as frequently insensitive to their needs or their knowledge of their own care, exchange of well-articulated information regarding how to deal with the system, and an apparent lack of awareness of any potential contribution of patient education or support system. 相似文献