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61.
Studies on removal of malathion from water by means of activated charcoal   总被引:1,自引:0,他引:1  
The utility of activated charcoal for the removal of malathion from saline waters has been explored. The adsorption capacity of charcoal for malathion has been found to be 117 mg g-1. Adsorption follows the Freundlich adsorption isotherms, the value of k and 1/n for charcoal being 1.6 and 0.60, respectively. Malathion can be eluted with methanol or ethanolic potassium hydroxide.  相似文献   
62.
A case of an odontogenic tumor which invaded the intracranial space from the mandible is reported. Judging from the radiographic images it was similar to a malignant tumor. The patient died 17 years after the first visit. According to the final pathological diagnosis, it was malignant odontogenic mixed tumor of low grade which did not belong to any of the WHO classification.  相似文献   
63.
A new axial skin flap based on the middle cutaneous branch of the medial plantar artery was evaluated in 33 fresh cadaver legs. The vascular pedicle of the skin flap is based on the middle cutaneous artery, its venae comitantes, and segments of the great saphenous vein, if necessary. The middle cutaneous artery is the largest cutaneous branch, arising from the medial plantar artery 2.5 cm distal to its origin. The diameter of its origin is 1.2 mm, and its pedicle is 2 cm long. The midline of the flap runs from the first web space to the heel tip. The upper and lower borders of the flap are 3 to 4 cm on either side of this line. The upper border is medial to the extensor hallucis tendon, and the lower border is medial to the abductor hallucis. Distally, the border begins 2 cm proximal to the metatarsalphalangeal joint; proximally, the border is at the middle of the medial malleolus. The flap diameter can be up to 8 × 12 cm. The middle cutaneous branch of the medial plantar artery was found in all cadaver specimens, except for one with a common trunk. The new flap design leaves the major blood supply to the foot and the plantar aponeurosis intact. It is easy to harvest and may be used either as an island flap or free flap. © 1995 Wiley-Liss, Inc.  相似文献   
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Unattached fractions of the radon progeny 218Po and 214Pb, size distributions for both unattached 218Po and 214Pb, and attached 214Pb and 214Bi, along with condensation nuclei (aerosol-particle concentrations), were measured in the open air of the city of El-Minia, Egypt. The measurements were performed with a wire-screen diffusion battery and a low-pressure Berner cascade impactor using standard methodologies. The results for parameters of derived distributions demonstrate that the distributions for the former (unattached 218Po and 214Pb) are nearly similar. The diffusion equivalent diameters (df) of 218Po and 214Pb were determined to be 1.4 and 1.55 nm with relative geometric standard deviations (σg) of 1.65 and 2.1, respectively. The latter distributions (attached 214Pb and 214Bi) are nearly identical. Most of the activities were associated with the aerosol particles of the accumulation mode. The mean activity median aerodynamic diameters (AMAD) of 214Pb and 214Bi have the same value of 380 nm but the relative geometric standard deviation of the log-normal distribution of 214Pb shows a broader activity distribution than 214Bi (σg = 2.2 for 214Pb and σg = 2.05 for 214Bi).  相似文献   
66.
The condensation reactions of hippuric acid and its furyl derivative with salicylaldehydes or that of salicylhippuric acid analogues with furaldehyde led to the corresponding oxazoles. These were subsequently treated with hydrazine hydrate, hydroxylamine or subjected to alkaline hydrolysis to yield new o-hydroxyaryl or salicyl containing derivatives. 5-Substituted salicylanilides were treated with piperidine and formaldehyde in a Mannich type reaction affording the corresponding 3-(N-piperidinomethyl) salicylanilides. It was noticed that the presence of an electron donating group in position 3 in the salicylanilide moiety decreases the molluscicidal activity.  相似文献   
67.
Both clinical and experimental investigations have shown that maternal hyperthermia during critical stages of embryo development can induce malformations in the offspring. Studies of the effect of heat stress on the placental functions are limited to the ewes, but that on microscopic structure is unknown. In the present study, rats were exposed to 41 or 42 degrees C for 1 h on gestation day (GD) 9. The controls were sham treated. Fetuses and placentas were collected on GD 20. Intrauterine growth retardation (IUGR) and several craniofacial malformations were observed in the fetuses of the heat-treated group. The placentas of the 42 degrees C group were significantly lighter in weight than those of the control. Light microscopy (LM) revealed thickening, hyalinization and occasional lymphocytic infiltration of the decidua basalis. Giant cells were prominent and glycogen cells had degenerated, leaving behind large cysts in the basal (spongy) zone. Best's carmine stain with or without diastase indicated the reduction in number and degeneration of glycogen cells and cyst formation. The labyrinthine zone was relatively thin in comparison to that of the controls. Perivascular fibrosis and paucity of vascularization were other features of the placentas of the hyperthermia group. Electron microscopy (EM) revealed lipid droplet accumulation in the trophoblast, the presence of myelin bodies and an increased production of collagen in the basal zone. Perivascular fibrosis appeared to have contributed to placental barrier thickening. EM also revealed accumulation of glycogen and lipid droplets in the trophoblasts and fibrin secretion into the extracellular space of the labyrinthine zone. These data suggest that placental pathology possibly contributes to fetal growth retardation in maternally heat-stressed rat fetuses.  相似文献   
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A 24-year-old man presented with a 24-hour history of pain and numbness in his left arm. The patient's clinical presentation of peripheral embolism was corroborated by angiography. Echocardiographic study showed masses in both right and left atria. Pathologic specimen from the embolus confirmed the diagnosis of aspergillosis.  相似文献   
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