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31.
Whereas water loss in land living animals occurs continuously, water intake takes place discontinuously. At the normal operating set point of plasma osmolality, urine is more concentrated than plasma due to secretion of vasopressin. Thus animals operate around a state of mild dehydration. As water loss occurs, the severity of dehydration and thirst increase in intensity and at some point water intake occurs. Sufficient water is consumed to return plasma osmolality to the normal operating set point. Food intake and water balance are interdependent as food provides the osmoles which determine obligatory renal solute excretion. When dry food with the same osmotic content was substituted for canned food (water content 74%), dogs increased water intake from 24.2 +/- 4.3 to 62.2 +/- 8.8 ml/kg. Urine output and urine osmolality were unchanged, as under conditions of normal hydration, near maximal urine concentration is achieved. Changing water intake is the only available variable to maintain water balance. During water deprivation, the major renal mechanism appears to be natriuresis. In rehydration, satiety mechanisms ensure appropriate water intake and renal sodium conservation restores sodium balance. 相似文献
32.
2%HPMC对兔眼内压及角膜内皮影响的实验研究 总被引:5,自引:0,他引:5
报导了2%羟丙基甲基纤维素(HPMC)、1%透明质酸钠(Na-HA)及平衡盐液(BSS)分别注入兔眼前房后,其眼内压、角膜内皮细胞数及内皮细胞形态的变化。证实自制2%HPMC 与进口1%Na-HA 性能基本相同,仅有一过性眼压升高,不损害角膜内皮,能在眼前节手术及人工晶体植入时有效地保护角膜内皮细胞。 相似文献
33.
目的采用电刺激大鼠上矢状窦(SSS)区硬脑膜,观察颈上交感神经节(SCG)摘除术前后在延髓和上颈段三叉神经脊束核一氧化氮合酶(NOS)阳性神经元数目的变化,以探讨交感神经系统在血管源性头痛(如偏头痛)涉及的伤害觉信息传递中的作用。方法以雄性SD大鼠(体重为220~250g)为实验对象,行颈上交感神经节摘除术后再手术暴露其SSS,然后电刺激SSS区硬脑膜,应用免疫组织化学染色技术,观察延髓和上颈段三叉神经脊束核NOS表达的变化。结果NOS免疫反应阳性神经元主要分布在三叉神经脊束核和上颈段脊髓的第Ⅰ、Ⅱ板层,双侧对称。假手术对照组、SCG摘除组每张切片的NOS阳性神经元数分别为150.2±10.3、223.0±11.6,SCG摘除组NOS阳性神经元数目较假手术对照组明显增加(P<0.05)。结论颈交感神经系统参与了头部血管源性疼痛(如偏头痛)中伤害性感觉信息导致的疼痛的产生、传导及调节过程。 相似文献
34.
35.
Takuya Onizuka M.D. Noriyoshi Sumiya M.D. Ryosuke Aoyama M.D. Yasuhiko Fukuya M.D. Takao Jinnai M.D. 《Aesthetic plastic surgery》1990,14(1):207-213
The results of repairing cleft lip by aesthetic plastic surgery are now excellent. However, the cleft lipnose deformity is still very difficult to repair with the present techniques. A technique that can repair the cleft lip-nose deformity with good results is presented. The technique is divided into three parts: Part I consists of nasal repair of the primary cleft lip. Part II is nasal reconstruction as a secondary operation with or without lip repair. For example, nasal reconstruction may be secondary to repair of deformities of the sill, rim, limen nasi, septum, or nasal bones. Part III is an aesthetic nasal operation such as rhinoplasty, mentoplasty, or zygomaplasty. 相似文献
36.
本文报道NIDDM患者在常规治疗的基础上加用钙剂和维生素D治疗后的钙代谢变化。糖尿病患者单纯用常规治疗控制血糖后,负钙平衡不能完全纠正,而加用钙剂和维生素D治疗后,负钙平衡能完全纠正,并且高于正常对照组平衡值(P<0.01)。说明钙剂加维生素D治疗对糖尿病性骨质疏松是有益的。 相似文献
37.
医院电子天平维护计量情况统计分析 总被引:1,自引:1,他引:0
电子天平具有体积小,功能齐全,操作简单,数值直观等优点,正为愈来愈多的医院、学校、科研单位所使用。本文结合我院五年中电子天平的使用、维护、计量情况,统计分析了其常见故障及电子天平使用中的注意事项。对保证医院电子天平使用过程的量值准确,提高临床诊断及科研水平有所帮助。 相似文献
38.
肺心病慢性呼吸性酸中毒合并代谢性酸碱失衡判断方法探讨(附80例次血气分析) 总被引:2,自引:0,他引:2
目的:对42例肺心病慢性呼吸性酸中毒患者的80例次血气测定结果。方法:用不同的酸碱图(卡)及代偿公式进行酸碱类型的初步差别分析。结果:结合临床表现、各种影响因素与治疗反应等作出综合判定。结论:比较二种判定的差异,并提出较为实用、可靠的判断建议,以助于复合型呼吸性酸碱失衡的临床诊断与处理。 相似文献
39.
A mature cystic teratoma in pineal region mimicking parietal encephalocele in a newborn 总被引:1,自引:0,他引:1
M. Kemali Baykaner Ertan Ergun Berker Cemil Pelin Bayik Hakan Emmez 《Child's nervous system》2007,23(5):573-576
Objective Teratoma is the most frequently encountered intracranial tumor at birth and constitutes 18–20% of all germ cell tumors. They
are usually located in pineal and suprasellar regions. The authors aim to report an extremely unusual presentation, location,
and appearance of a teratoma in a newborn.
Case report A soft tissue swelling in the vertex was detected in a 1-month-old girl. Neurological examination was normal. A big, cystic–solid
lesion beginning from pineal region and extending to the scalp was detected in magnetic resonance imaging. It is interesting
to note that cerebral venous angiography showed that the superior sagittal sinus (SSS) was divided into three branches at
the level of the lesion and they joined together distally. The tumor was excised totally. Histopathological examination revealed
the diagnosis of a mature cystic teratoma.
Conclusion A mature cystic teratoma mimicking parietal encephalocele is extremely rare. Germ cell tumors should be kept in mind in the
differential diagnosis of all midline lesions with unusual radiographic appearance. Cerebral venous angiography or MR angiography
must be performed for the diagnosis and the surgical planning in lesions located near SSS. 相似文献
40.
Friedrich Manz Hermann Kalhoff Thomas Remer 《Pediatric nephrology (Berlin, Germany)》1997,11(2):231-243
In early infancy, complex disorders of acid base metabolism are more frequent than in any other age group, with a predisposition
to metabolic acidosis due to an age-related low renal capacity for acid excretion and an unphysiologically high actual renal
acid load in nutrition with common formulas. Recently in preterm and small-for-gestational-age infants, persistent maximum
renal net acid excretion (NAE) with subnormal or normal blood acid base status, impaired weight gain, and adaptive hormonal
reactions have been observed. Incipient late metabolic acidosis is one example of a mixed disorder of acid base metabolism
with maximum renal NAE in early infancy. Alkali therapy is highly effective and can be realized both on an individual basis,
using urine pH screening as a diagnostic criterium for maximum renal acid stimulation, or on a general preventive level using
modified standard formula with a reduced actual renal NAE similar to that seen on alimentation with human milk. From an integrated
point of view, the low glomerular filtration rate and renal capacity for acid excretion beyond the developmental age of more
than 44 weeks, may well be interpreted as the result of a specific adaptation to breast feeding sparing energy, and thus an
evolutionary advantage for the survival of mother and child.
Received July 10, 1996; received in revised form and accepted October 7, 1996 相似文献