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61.
62.
乳酸中毒和pH对狗肺血管张力和气体交换功能影响的实验研究 总被引:1,自引:0,他引:1
急性代谢性酸中毒对狗血管张力和气体交换功能的影响进行了研究。当滴入乳酸或盐酸造成急性代谢性酸中毒(pH7.00)时,可引起肺血管收缩,肺动脉压力明显升高,血氧饱和度下降,并且乳酸和盐酸引起的酸中毒对肺动脉平均压影响程度相似,提示肺血管收缩和肺动脉压升高的程度与血中pH值下降关系密切,而与此时血中乳酸水平的高低无关。 相似文献
63.
The aim of our study was to determine the possible pathophysiological mechanisms of hypophosphataemia in a group of 127 patients admitted to hospital for alcohol-related causes. Blood and fresh urine specimens were taken to determine acid-base and electrolyte parameters. Thirty-seven patients (29.1%) had hypophosphataemia (serum phosphorus <0.77 mmol/l) with a range of serum phosphorus of 0.32-0.74 mmol/l. In 17 hypophosphataemic patients inappropriate phosphaturia (FEP04 >20%, TmPO4/GFR<0.80 mmol/l) was evident, possibly due to hypomagnesaemia, metabolic acidosis, metabolic alkalosis, or a proximal tubular defect in phosphate transport. The causes of hypophosphataemia in the remaining 20 patients were alcohol withdrawal syndrome, respiratory alkalosis and diarrhoea. Patients with hypophosphataemia were more often found to have hypomagnesaemia and respiratory alkalosis than normophosphataemic patients. In conclusion, hypophosphataemia is frequently observed in alcoholic patients due to various pathophysiological mechanisms, such as inappropriate phosphaturia, increased phosphorus entry into cells and increased gastrointestinal loss of phosphate. 相似文献
64.
A histologically visible representation of the fingers and palm in primate area 3b and its immutability following long-term deafferentations 总被引:1,自引:1,他引:0
An isomorph of the glabrous hand is visible in primary somato-sensory
cortex (area 3b) of owl monkeys in brain sections cut parallel to the
surface and stained for myelin. A mediolateral row of five ovals, separated
by myelin-light septa, represents digits and corresponds precisely with
cortical sites activated by light touch on individual digits in
microelectrode recordings. A number of caudal ovals relate to pads of the
palm. A more distinct septum separates the hand from the more lateral face
representation. Within the face representation, two large myelin-dense
ovals can be identified that are activated by the upper or lower face in a
caudo-rostral sequence. Accidental finger loss or dorsal column section,
deafferentations that result in reorganization of the physiological map in
area 3b, do not alter the morphological map. The proportions for each digit
and palm in the morphological map do not vary across normal and
deafferented animals. Similar isomorphs were also seen in area 3b of
squirrel and macaque monkeys. We conclude that the anatomical isomorph for
the body surface representation in area 3b is a reliable reflection of
normal cortical organization and may be a common feature of the primate
area 3b. The isomorph can provide a reference in studies of somatotopic
reorganization.
相似文献
65.
Continuous wave Doppler echocardiography after surgical repair of coarctation of the aorta
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Objective—To find how closely pressure gradients across the aortic arch derived from Doppler echocardiography reflect gradients measured by catheter after surgical repair of coarctation of the aorta.Design—Pressure drop across the aortic arch was measured simultaneously by continuous wave Doppler and double lumen catheter in 20 patients with repaired coarctation of the aorta.Results—The peak pressure drop estimated by Doppler was almost invariably higher than the peak to peak gradient measured by catheter, as might be expected. Wide variation was seen between the Doppler measured pressure drop and instantaneous peak gradient measured by catheter, ranging from +22 to −17 mm Hg. The reasons for these differences are unclear but are probably related to a combination of complex flow dynamics in the aortic arch, difficulty in closely aligning the Doppler beam with flow, and inability to measure flow velocity immediately proximal to the site of the surgical repair with continuous wave Doppler.Conclusions—Continuous wave Doppler echocardiography may significantly overestimate or underestimate the pressure drop after repair of coarctation and it should be interpreted with caution in individual patients. Catheterisation with angiography remains the reference standard for assessment of surgical repair of the aortic arch. 相似文献
66.
Cyclic vomiting syndrome in South-East Asian children 总被引:3,自引:0,他引:3
67.
Magnetic resonance (MR) imaging, correlated with anatomic sections, was used to characterize the progressive and regressive changes in the nucleus pulposus in neonates. The spines of five fetuses and five full-term infants between 16 and 40 weeks old were studied. In anatomic sections, the nucleus pulposus was sharply demarcated from the anulus fibrosus, Sharpey fibers were conspicuous, and a plate of primitive notochord was evident in the equator of the disk. On long repetition time (TR)/long echo time (TE) or long TR/short TE MR images, Sharpey fibers (low signal intensity) and notochord (low signal intensity) could be differentiated from the high-signal-intensity nucleus pulposus and anulus fibrosus. The major differences between the fetal and infant spines were the amount of notochord in the disk and ossification in the vertebral body. 相似文献
68.
A L Nwoku 《International journal of oral surgery》1979,8(4):271-275
Although the probability of ankylosis following injury of the temporomandibular joint is small, patients, especially children with temporomandibular joint ankylosis, are greatly handicapped. Of the 42 cases of ankylosis seen in our clinic, six occurred in the adult, and 36 in children under 14 years of age. Treatment in all cases was surgical, and the results were beneficial, although the greatest difficulty in the treatment had been the early recurrence of ankylosis. Based on our experience, osteoarthrotomy for temporomandibular joint ankylosis in children has been advocated. 相似文献
69.
70.
KC Han-Ching Wang Chun-Wei Tseng Han-You Lin I-Tung Chen Ya-Hui Chen Yi-Min Chen Tzong-Yueh Chen Huey-Lang Yang 《Developmental and comparative immunology》2010,34(1):49-58
In this study, we used real-time PCR to simultaneously monitor the responses of 12 key genes of the shrimp innate immune system in Litopenaeus vannamei after challenge with Vibrio harveyi. In the proPO activating system, we found that proPO was up-regulated (3.3× control at 36 hpi). The hemolymph clotting genes transglutaminase (TGase) and clotting protein were also up-regulated, as were 5 genes in the antimicrobial peptide system (ALF, Crustin, Lyz, PEN2 and PEN4), with only PEN3 showing no significant changes. In the antioxidant defense system, SOD was slightly elevated while GPx was substantially down-regulated. In the pattern recognition receptor system, at 24 hpi, the Toll gene (LvToll) showed the highest relative increase in expression level of all the investigated genes (15× greater than the sterile seawater control). In the second part of this study, when LvToll was knocked down by RNAi silencing, there was no effect on either survival rates or bacterial number in unchallenged shrimp. There was also no difference in mortality rates between control shrimp and LvToll-silenced shrimp when these two groups were challenged with a viral pathogen (white spot syndrome virus; WSSV). However, when LvToll-silenced shrimp were challenged by V. harveyi, there was a significant increase in mortality and bacterial CFU counts. We note that the increase in bacterial CFU count occurred even though treatment with EGFP dsRNA had the opposite effect of reducing the CFU counts. We conclude that LvToll is an important factor in the shrimp innate immune response to acute V. harveyi infection, but not to WSSV. 相似文献