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121.
海洋丝状真菌转化石油烃的研究   总被引:8,自引:0,他引:8  
研究从湄洲湾海域分离的4株丝状真菌MF1,MF2,MF3,MF4的生长特性及去除油污的过程,观察在温度26℃,初始油浓度在3g/l,培养12d的过程中培养液的变化,分析培养液的pH值及原油的去除率与时间的关系,结果表明,丝状真菌去除原油的[过程是生物吸附与生物降解相结合的生物转化过程,比较革兰氏阴性细菌与丝状真菌细胞壁组成,结构,得出海洋微生物的脱油作用与其细胞壁有直接的关系。  相似文献   
122.
A prospective study was conducted on 374 patients with urinary lithiasis, aiming to analyze the participation of oxalate in the lithogenesis and composition of the calcium oxalate calculi, alone or associated to other factors. METHODOLOGY: Metabolic urinary study of the patient and analysis of calculi with infrared spectrography and optical microscopy. RESULTS: 26.3% patients had hyperoxaluria and 77.5% of the calculi contain calcium oxalate; these are 167 cases of calcium oxalate, 110 of oxalate and calcium phosphate and 13 cases of mixed calcium oxalate and uric acid lithiasis. 43.4% patients with pure monohydrate calcium oxalate calculi have hypercalciuria, 22.6% hyperoxaluria and 19% hyperuricosuria. Dihydrated calcium oxalate calculi are related to high hypercalciuria in 65% cases and to significant hyperoxaluria in 35% cases. 45% patients present a single lithogenic factor, either hypercalciuria (49.6%), hyperoxaluria (20.6%), hyperuricosuria (13.74%), hypocitraturia (9%), urinary infection (1.5%), A.T.R. (2.25%) or acid oliguria (3%).  相似文献   
123.
This paper describes a rapid, specific and sensitive multiresidue method for the routine analysis of several classes of pesticides used for the treatment of apples and pears, involving a rapid extraction procedure at pH 4.5 with a mixture of acetone-dichloromethane-hexane (50:20:30, v/v/v) and gas chromatography coupled to mass-selective detection, in order to achieve quantitative analysis down to their respective maximum residue limit. Extraction recoveries were between 55 and 98%. Limits of detection and limits of quantitation ranged respectively, from 0.01 to 0.05 mg/kg and from 0.02 to 0.1 mg/kg. Intra-assay relative standard deviation was less than 19% for all compounds. An excellent linearity was observed from these LOQs up to 500 mg/kg. Intermediate (inter-assay) precision and accuracy were satisfactory. The method has been applied to many fruit samples intended for commercialisation.  相似文献   
124.
125.
BACKGROUND/PURPOSE: The development of thoracoscopic surgery has made many procedures possible, including the treatment of mediastinal cysts in children. The authors report their experience with this procedure between 1992 and 1997. METHODS: Surgery was performed on 22 children aged from 1 month to 9 years (median, 27 months), weighing 5 to 49 kg (median, 12.5 kg). Diagnosis was made by antenatal ultrasound scan in six cases (27%), with a chest x-ray performed for respiratory symptoms in 14 cases, and with a chest x-ray performed for positive tuberculin intradermoreaction in two cases. Decision to resect the cyst was determined by thoracoscopy in 21 of the 22 cases, and by open surgery in one case only (subcarinal compressive cyst with left lung distension and a mediastinal shift). RESULTS: Eighteen of the 21 (86%) cases were treated successfully by thoracoscopy. In three cases of bronchogenic cysts, we performed an associated thoracotomy because the dissection was too difficult and dangerous. In three cases, a small part of a common wall between the cyst and the bronchus was not removed. The pathological diagnosis was bronchogenic cysts in 15 cases (71%), pleuropericardiat cysts in three cases (14%), esophageal duplication in two cases (10%), and cystic hygroma in one case (5%). Two postoperative complications were observed: one esophageal wound and a case of recurrent pneumothorax after chest tube removal. Patients were discharged after 2 to 11 days (median, 3 days). Follow-up was uneventful. CONCLUSIONS: Treatment of mediastinal cyst by thoracoscopy is feasible in most cases. Compressive cysts with lung distension and mediastinal shift remain a contraindication. If the cysts have a common wall with the bronchus or esophagus, or if they are subcarinal, the dissection may be difficult and dangerous, and thoracotomy may be preferable.  相似文献   
126.
BACKGROUND: Nightshade plants (Solanaceae) have been utilized as hallucinogenic drugs since antiquity in nearly every culture. The Solanaceae alkaloids, atropine and scopolamine, were the active substances in ointment of witches and medieval anesthetics, and in modern poisons. They are still currently used as hallucinogenic drugs. In poisonings, a dosage- and substance-dependent clinical picture occurs, with central and peripheral symptoms. Hallucinations are predominant in the middle dose range, which explains the drugs' earlier utilization for religious and prophetic purposes. Respiratory depression and arrest at high doses confirm the use of scopolamine as a lethal poison. Despite this, the nightshade alkaloids were utilized in clinical medicine in the 19th century. This is an overview of the cultural history of the nightshade alkaloids.  相似文献   
127.
PURPOSE: To evaluate the effectiveness, predictability, and safety of clear lens extraction to correct extreme myopia. SETTING: Clinica de Nuestra Se?ora de la Concepción, Fundación Jiménez Díaz, Madrid, Spain. METHODS: This retrospective study comprised 26 eyes of 17 highly myopic patients who had clear lens extraction and implantation of a negative-power posterior chamber intraocular lens (IOL). The IOL power was calculated using the SRK/T formula. Analyzed were visual and refractive results and intraoperative and postoperative complications. Follow-up was at least 12 months in all cases. RESULTS: Uncorrected visual acuity improved in all cases, with 80.77% of eyes achieving 20/100 or better and 42.30%, 20/40 or better. Best spectacle-corrected visual acuity (BSCVA) improved in 23 eyes (88.46%). The percentage of eyes achieving a BSCVA of 20/100 or better increased from 73.07% preoperatively to 92.30% postoperatively and the percentage achieving 20/40 or better, from 23.07 to 73.07%. Of the 26 eyes, 76.91% were within 1.00 diopter (D) of refractive error and 96.16% were within 2.00 D. No intraoperative complications occurred. Although postoperatively 3 eyes (11.53%) developed choroidal detachment and 5 (19.23%) had an intraocular pressure greater than 25 mm Hg, all had a favorable outcome. Four eyes (15.38%) developed posterior capsule opacification and had a neodymium:YAG laser posterior capsulotomy 6 months postoperatively. No retinal detachments were observed. CONCLUSION: Clear lens extraction with negative-power IOL implantation using the SRK/T formula had good effectiveness, acceptable predictability, and a low morbidity in eyes with extreme myopia over a short follow-up. A longer follow-up with more cases is needed to assess the safety of the procedure.  相似文献   
128.
An enantioselective synthesis of the (1'S,2'R)-dimethylheptyl cannabinoid side chain has been developed and employed in the synthesis of 11-hydroxy-(1'S,2'R)-dimethylheptyl-delta 8-THC (3). Pharmacology, in vivo and in vitro, indicate (3) to be one of the most potent traditional cannabinoids known.  相似文献   
129.
Delta opioid peptide [D-Ala2,D-leu5]enkephalin (DADLE) can prolong organ preservation and increases myocardial tolerance to ischemia. Our study examined the protective property of DADLE against methamphetamine- (METH) induced dopaminergic terminal damage in the central nervous system. Because the neurotoxicity of METH involves reactive oxygen species, we also examined if DADLE might be an antioxidative agent in vitro. DADLE at 2 and 4 mg/kg (i.p.), given 30 min before each METH administration (5 or 10 mg/kg, i.p., four injections in a day at 2-hr intervals), dose-dependently blocked the METH-induced long-term dopamine transporter loss. The opioid antagonist naltrexone blocked this action of DADLE in both aspects of striata but tends not to affect the effects of DADLE in the nucleus accumbens. DADLE did not alter changes in body temperature induced by METH. The reduction of striatal dopaminergic content and tyrosine hydroxylase activity caused by METH, however, were not blocked by DADLE. In vitro, DADLE was approximately equipotent to glutathione in inhibiting both superoxide anion formation induced by xanthine oxidase and hydroxyl radical formation evoked by ferrous/citrate complex. DADLE was only slightly less potent than glutathione in inhibiting the iron/ascorbate-induced brain lipid peroxidation. These results suggest that DADLE can protect the terminal membranes of dopaminergic neurons against METH-induced insult but not the loss of dopaminergic content and tyrosine hydroxylase activity and that this action of DADLE might involve opioid receptors as well as the sequestration of free radical.  相似文献   
130.
This experiment consisted of the following treatment-breed groups: 1) White crossbred gilts, 2) White crossbred gilts treated with progesterone (200 mg/d in corn oil given on d 2 and 3 after estrus), and 3) Chinese Meishan gilts. Pregnant and nonpregnant gilts (n=3 to 6) from each treatment-breed combination were assigned to be slaughtered on d 10, 11, 12, 13, and 15. At slaughter each uterine horn was flushed with 20 mL of minimal essential medium. Uterine flushings were assayed for total protein, acid phosphatase, uteroferrin, retinol-binding protein, and oxytocin. Uterine flush total protein was increased by progesterone treatment, was unaffected by pregnancy status, and was less in Meishans. Similar patterns were found for retinol binding protein and uteroferrin, except that uteroferrin was greater in pregnant than in nonpregnant gilts. Oxytocin was greater in pregnant than in nonpregnant gilts, was not influenced by progesterone treatment, and was similar in Meishan and in White crossbred gilts. These results indicate that the conceptus does not influence secretion of either total protein or retinol binding protein during pregnancy and that the onset of secretion of these uterine proteins may be controlled by progesterone. The presence of the conceptus is associated with increased uteroferrin and oxytocin production. The decreased secretion of uterine proteins in Meishan gilts may partially explain the slower embryonic development that has been reported for this breed.  相似文献   
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