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991.
H. Matschiner F. Cotta R. Voigtlnder H. Schilling 《Advanced Synthesis \u0026amp; Catalysis》1977,319(4):561-567
Electrochemical Synthesis of 2, 2-Dichloroethenyl-dialkyl-phosphoric Acid Esters The reaction of O-1,2,2,2-tetrachloroethyl phosphorodichloridate 3 with alcohols or phenols gives symmetrical or unsymmetrical O, O-diorgano-O-1,2,2,2-tetrachloroethyl phosphates 2 , which can be reduced electrochemically. In this reaction two vicinal chlorine atoms are eliminated. This reaction results in compounds with high biological activity, especially as insecticides. The synthesis and the polarographic behaviour of various O, O-di-organo-O-1,2,2,2-tetrachloroethyl phosphates 2 as well as the preparative techniques of the electrochemical elimination of chlorine are described. 相似文献
992.
A Senagore WP Mazier MA Luchtefeld JM MacKeigan T Wengert 《Canadian Metallurgical Quarterly》1993,36(11):1042-1049
PURPOSE: Recently, laser technology has been advocated for the treatment of hemorrhoids. However, there has been little scientific evaluation of the use of the Nd:YAG laser for excisional treatment of hemorrhoidal disease. The purpose of this study was to perform a prospective randomized study of the Nd:YAG laser vs. scalpel excision, when performing a standard Ferguson-closed hemorrhoidectomy. METHODS: Patients presenting for internal-external hemorrhoidectomy were eligible for study. Hemorrhoidectomies were performed under epidural or caudal blocks. The standard Ferguson closed hemorrhoidectomy technique was used. Data evaluated included: age, sex, estimated blood loss, operative time, postoperative pain scores, postoperative analgesic use, wound healing, and time for return to work. Eighty-six patients were eligible for study (laser, N = 51; scalpel, N = 35). RESULTS: There were no significant differences between the groups, except for a greater degree of wound inflammation and dehiscence at the 10 day postoperative visit for the laser group (laser, 1.7 +/- .2; scalpel, 0.8 +/- .2; P < 0.05, t-test). The use of the Nd:YAG laser added $480 per case; as a result, the treatment cost for the laser group was $15,360 higher than that of the conventional group. CONCLUSION: The results indicate that there are no patient care advantages associated with the use of the Nd:YAG laser for excisional hemorrhoidectomy compared with scalpel excision. As new technology becomes available, surgeons must rigorously assess therapeutic efficacy and cost-benefit ratio before deciding to employ this technology for patient care. 相似文献
993.
1. Male rats given daily intraperitoneal injections of fluoxetine (10 mg/kg) were slower to escape foot shock by jumping a low barrier. 2. When switched to a shuttle task requiring two crosses to terminate shock, the FLU-treated animals failed to learn in 55 trials. 3. A second experiment found FLU-treated animals could learn a one-way avoidance response, but were significantly slower to learn than control animals. 4. FLU-treated animals were no different than controls on tests of sensory thresholds for foot shock or heat. 5. Tests of motor behaviors revealed no differences in latency to traverse a narrow beam to reach a goal box, however FLU-treated animals were less active in an open field. 6. Several hypotheses can account for these data, the most promising being that a central motivational system (fear) is less active in FLU-treated animals. 相似文献
994.
S Bhasin TW Storer N Berman KE Yarasheski B Clevenger J Phillips WP Lee TJ Bunnell R Casaburi 《Canadian Metallurgical Quarterly》1997,82(2):407-413
To test the hypotheses that plasma volume (PV) expansion 24 h after intense exercise is associated with reduced transcapillary escape rate of albumin (TERalb) and that local changes in transcapillary forces in the previously active tissues favor retention of protein in the vascular space, we measured PV, TERalb, plasma colloid osmotic pressure (COPp), interstitial fluid hydrostatic pressure (Pi), and colloid osmotic pressure in leg muscle and skin and capillary filtration coefficient (CFC) in the arm and leg in seven men and women before and 24 h after intense upright cycle ergometer exercise. Exercise expanded PV by 6.4% at 24 h (43.9 +/- 0.8 to 46.8 +/- 1.2 ml/kg, P < 0.05) and decreased total protein concentration (6.5 +/- 0.1 to 6.3 +/- 0.1 g/dl, P < 0.05) and COPp (26.1 +/- 0.8 to 24.3 +/- 0.9 mmHg, P < 0.05), although plasma albumin concentration was unchanged. TERalb tended to decline (8.4 +/- 0.5 to 6.5 +/- 0.7%/h, P = 0.11) and was correlated with the increase in PV (r = -0.69, P < 0.05). CFC increased in the leg (3.2 +/- 0.2 to 4.3 +/- 0.5 microl . 100 g-1 . min-1 . mmHg-1, P < 0. 05), and Pi showed a trend to increase in the leg muscle (2.8 +/- 0. 7 to 3.8 +/- 0.3 mmHg, P = 0.08). These data demonstrate that TERalb is associated with PV regulation and that local transcapillary forces in the leg muscle may favor retention of albumin in the vascular space after exercise. 相似文献
995.
J Lee PH Jones JE Trowell WP Whitear PF Williams 《Canadian Metallurgical Quarterly》1993,27(2):181-183
We report a case of disseminated histoplasmosis presenting with acute renal impairment due to adrenal insufficiency. The finding of bilateral adrenal gland enlargement on abdominal ultrasound examination led to a diagnostic CT-guided adrenal biopsy. Prolonged therapy with amphotericin and itraconazole resulted in a clinical cure, although the patient still requires adrenal replacement therapy. 相似文献
996.
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999.
Scheinberg N. Feria E. Barba J. Schilling D. 《Communications, IEEE Transactions on》1984,32(7):861-863
This paper describes a one-stage look-ahead algorithm for adaptive delta modulators. The algorithm does not require the calculation of two encoding paths nor does it require the decision circuitry to choose the optimum path. 相似文献
1000.
Basal and pentagastrin-stimulated peak acid outputs were determined in 21 subjects with chronic atrophic gastritis and 10 subjects with chronic superficial gastritis. All subjects were Caucasian. The histological diagnosis was based on multiple gastric biopsy specimens obtained through a fibregastroscope. Comparison of the results with those of a previously reported Caucasian control group show that the mean basal acid outputs of subjects with chronic (superficial) gastritis were significantly higher than that of controls and subjects with chronic atrophic gastritis. No significant difference was found in the mean peak acid outputs of controls and subjects with chronic atrophic gastritis or chronic (superficial) gastritis. 相似文献