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31.
32.
The effect of the hepatic energy status on the development of posttraumatic jaundice (PTJ) was studied to clarify the mechanism of PTJ. Fifty-four patients with severe torso injury who were expected to develop PTJ on admission with an average Injury Severity Score of 27 were selected for this study. They were retrospectively divided into three groups according to their maximum bilirubin concentration by day 10: group H, 12 patients with marked elevation of serum bilirubin (>8 g/dl); group L, 23 with mild bilirubinemia (2–8 g/dl); and group N, 19 with no bilirubinemia (<2 g/dl). Group H patients, in whom trauma-related shock was severe and prolonged, developed severe hyperbilirubinemia, and their arterial ketone body ratio (AKBR), which reflects the hepatic mitochondrial redox state and is closely correlated to its energy production, was significantly lower throughout the first week. In contrast, the AKBR increased to an above normal level, indicating enhanced energy production in groups N and L. The serum direct/total bilirubin was also higher in group H. The abnormal hepatic energy metabolism is considered to have reduced the excretion of conjugated bilirubin from the hepatocytes into the bile canaliculi, which is a process that has to proceed against the bilirubin concentration gradient. The subsequent diffusion of the accumulated water-soluble conjugated bilirubin in hepatocytes into the blood is thus considered to be one of the causes of PTJ.  相似文献   
33.
Effects of adrenergic alpha-1-blocking agent, prazosin, in the treatment of detrusor external-sphincter dyssynergia (DSD) were evaluated in both experimental and clinical aspects. Experimentally, in the urethral pressure profile in dogs, the maximum urethral closing pressure was depressed after intravenous injection of 1 mg prazosin. When experimental DSD was obtained in dogs by stimulating electrically the unilateral 2nd sacral root, intra-venous injection of 1 mg prazosin inhibited contraction of the external urethral sphincter. Clinically, 74 patients with DSD based on neurogenic bladder from cerebral vascular attack (CVA) (13 cases) and spinal cord injury (61 cases) were retrospectively surveyed in terms of therapeutical effects of prazosin for DSD. Spinal cord injury was subdivided to 4 groups for clinical evaluation; cervical cord injury (C) with complete paralysis, thoracic cord injury (Th) with complete paralysis, lumbar cord injury (L) with complete paralysis and spinal cord injury with incomplete paralysis. Patients with CVA and spinal cord injury with incomplete paralysis showed good response rates in subjective improvement, 69% and 60% respectively. However, those with spinal cord injury with complete paralysis showed a poor response (28% for C, 23% for Th and 14% for L). The amount of residual urine significantly decreased after treatment, in all the groups except that of lumbar cord injury with complete paralysis. In all the groups, however, even after the drug treatment the amount of residual urine ranged from 80 to 170 ml and the rates of needing clean intermittent catheterization unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
34.
The thermal conversion of 1 alpha-hydroxyprevitamin D3 (1 alpha-OH-previtamin D3) diacetate to 1 alpha-hydroxyvitamin D3 (1 alpha-OH-vitamin D3) diacetate was investigated in five solvents. The fraction of 1 alpha-OH-vitamin D3 diacetate was calculated from the HPLC peak areas (UV detection) of 1 alpha-OH-previtamin D3 diacetate and 1 alpha-OH-vitamin D3 diacetate. When 1 alpha-OH-previtamin D3 diacetate was dissolved in ethanol, benzene, toluene, isopropyl ether, or n-hexane, and heated at 60 degrees C, the yield of 1 alpha-OH-vitamin D3 diacetate increased during the first 4 h, and reached an equilibrium level after 8.5 h. Differences in the ratio of 1 alpha-OH-previtamin D3 diacetate to 1 alpha-OH-vitamin D3 diacetate at thermal equilibrium, and in the rate of the thermal isomerization were observed among these five solvents. Molecular mechanics (MM) calculations were performed in order to estimate solvent effects on conformation for 1 alpha-OH-previtamin D3 diacetate and 1 alpha-OH-vitamin D3 diacetate. The solvent effect was treated by specifying a dielectric constant representative of each of the three solvents: ethanol (polar), n-hexane (nonpolar), and benzene (aromatic). The dielectric constants used were 24.3 for ethanol, 1.5 for n-hexane, and 2.3 for benzene. It is suggested that the conformation of 1 alpha-OH-vitamin D3 diacetate is stabilized in polar solvent. However, the order of conformational stability when solvent effects are included in the calculations is: ethanol greater than benzene greater than n-hexane. This order does not follow the experimental results. The proton NMR chemical shifts of 1 alpha-OH-vitamin D3 diacetate are different in deuterated n-hexane, ethanol, and benzene. The downfield shift of the C-6 vinyl proton of 1 alpha-OH-vitamin D3 diacetate, when compared to the chemical shift in benzene, is 0.15 and 0.11 ppm relative to the chemical shift in n-hexane and ethanol, respectively, and that of the C-7 proton was 0.30 and 0.33 ppm, respectively. No significant proton shift of 1 alpha-OH-previtamin D3 diacetate is recorded in these three solvents. To account for the increased ratio of 1 alpha-OH-vitamin D3 diacetate to 1 alpha-OH-previtamin D3 diacetate ratio in benzene, we suggest that 1 alpha-OH-vitamin D3 diacetate may be stabilized via specific solute-solvent interactions in benzene.  相似文献   
35.
36.
Gliomatosis cerebri with good prognosis   总被引:4,自引:0,他引:4  
A 52-year-old man was admitted to our clinic with severe headache and bilateral papilledema. Magnetic resonance (MR) images on admission demonstrated diffuse swelling of the cerebral cortex without formation of a tumor mass. Biopsy revealed diffuse infiltration with neoplastic glial cells. After radiation and chemotherapy, the MR images returned to normal. The morphological and neurological features of the present case met the criteria for gliomatosis cerebri. However, this patient showed an unusually good response to radiation and chemotherapy.  相似文献   
37.
This paper describes a new class of reaction, group-transfer alternating copolymerization (GTAC), between 2-phenyl-1,3,2-dioxaphosphorinane ( 1 ) and trimethylsilyl 2-(acryloyloxy)ethanesulfonate ( 2 ). The copolymerization took place without any added catalyst and proceeded via quantitative trimethylsilyl group-transfer process to give a 1:1 alternating copolymer 3a having a ketene silyl acetal group in the main chain. Results of spectroscopy as well as alkaline hydrolysis and bromination of the copolymer confirmed the structure.  相似文献   
38.
Thoracic duct cyst in supraclavicular region.   总被引:1,自引:0,他引:1  
A 28-year-old female attended an outpatient clinic in October, 1989, because of a tumor in the left supraclavicular fossa, detected in a health examination. Following exploratory puncture of the tumor which yielded milky-white fluid, suggesting a cyst in the thoracic duct, she was admitted to our department. The cyst was unilocular measuring about 6 cm in diameter, and the fluid content was chyle-rich in lipids. Lymphography demonstrated a lymphatic structure adjacent to the lesion and scattered lymph vessels on the cyst surface. On November 16 the cyst was resected. A restiform structure was observed between the cyst and the thoracic duct, but the presence or absence of communication was unclear. The histological diagnosis was thoracic duct cyst. Thoracic duct cyst occurring in the cervical region is very rare. Our case may provide useful information as to its pathogenesis and the mode of retention of cyst fluid.  相似文献   
39.
The midportion of the anterior cruciate ligament (ACL) of rabbits was partially transected, and the effect of hyaluronan (HA) on its healing was determined. A 1% solution of HA (HA group) or physiological phosphate-buffered saline (control group) was administered intraarticularly, at 0.1 ml/kg body weight, once a week from 1 week after the operation. Two, 4, and 6 weeks after the initiation of HA administration, the ACLs were examined grossly, histologically and immunohistochemically. At 2 weeks, the lacerated portions were completely covered with scar-like tissue in both groups. These tissue areas were smaller in the HA group than in the control group. Histologically in the HA group, the regularity of collagen fibers (indicating the maturity of regenerated collagen fibers) had increased compared to findings in the control group, and the number of fibroblastic cells decreased gradually at a significantly faster rate. The number of inflammatory cells and blood vessels decreased gradually in both groups, with these values being lower in the HA group at each time point but not significantly so. Immunohistochemical examination of the repaired tissue revealed strong staining with anti-chondroitin sulfate proteoglycan antibody in the HA group 2 weeks after the first HA administration. The staining gradually became reduced, with the rate of reduction being faster in the HA group than in the control group. The stimulation of chondroitin sulfate proteoglycan production and the faster reduction of it in the HA group suggests that HA facilitated tissue repair and inhibited the formation of scar tissue.  相似文献   
40.
Using tension-recording methods, we compared the effects of acetylcholine (Ach) and carbachol on the bovine iris sphincter. The isolated muscle strips were mounted in a 0.2 ml organ bath, through which Krebs solution at 36 °C flowed continuously. There was a tenthousandfold difference in potency between carbachol and Ach in this tissue. Neostigmine or eserine, acetylcholinesterase (AchE) inhibitors, produced a larger contraction of the muscle than did Ach. Ach-induced contractions were potentiated by low doses of anti-AchEs and were inhibited by atropine.This in vitro study suggests that Ach and/or endogenous chemical agents may be spontaneously released from tissues and that AchE activities in this tissue strongly inhibit or mask the Ach action, probably in order to protect the nerve terminals from released Ach.  相似文献   
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