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991.
Experience with the 'skew flap' below-knee amputation 总被引:3,自引:0,他引:3
A review of 353 lower limb amputations over the last 7 years has been performed to assess the results of the skew flap myoplastic below-knee amputation which was introduced in April 1983 because of reported advantages in terms of wound healing and earlier ambulation. Comparing the first 3 1/2 year period with the second, the total number of amputations decreased by 31 per cent. The number of above-knee amputations remained similar in the two periods (82,62), whilst the number of Gritti-Stokes amputations fell from 79 to 21 (0.001 greater than P greater than 0.01). The proportion of below-knee (BK) amputations increased from 50 (23.7 per cent) to 59 (41.5 per cent) (0.01 greater than P greater than 0.025). The groups were comparable in terms of previous vascular surgery and co-existing medical conditions. The time to full stump healing was significantly shorter in the skew flap group compared with the earlier Burgess type BK amputation (P = 0.001), and there was a trend to fewer stump failures in the skew flap group. We therefore feel that the skew flap amputation gives superior results to the Burgess BK amputation in terms of healing and a lower complication rate, allowing a higher proportion of BK amputations to be performed. A prospective randomized trial of the two techniques is in hand to determine the accuracy of this hypothesis. 相似文献
992.
Ambient light affects pulse oximeters 总被引:1,自引:0,他引:1
993.
Topical analgesia for relief of post-circumcision pain 总被引:1,自引:0,他引:1
994.
N.B.SIMPSON 《The British journal of dermatology》1987,117(1):43-47
Sebum excretion rate was measured by a photometric technique. We demonstrated a high correlation between sebum excretion rates on the left and right sides of the upper back and between back and forehead skin. Sebum excretion rate measurements overlying an open comedone (blackhead) were significantly lower than those obtained from normal skin. This observation demonstrates a functional obstruction to the outflow of sebum and would suggest that the lack of involvement of open comedones in inflammatory acne is not because of the maintenance of a free flow of sebum. 相似文献
995.
J M Battagel 《Dental update》1987,14(3):119-20, 123-4
996.
Three evaluation instruments (global, check-list, and criterion referenced) were used by experienced and inexperienced examiners to evaluate dental sealant end products on 40 extracted teeth. Intra- and interexaminer reliabilities were measured. Experienced examiners achieved higher intrarater reliabilities with all three evaluation instruments than did inexperienced examiners. The highest intraexaminer agreement for all examiners occurred with use of the global evaluation. The highest interexaminer reliability was achieved with the second use of the criterion-referenced evaluation by the experienced examiner. Interexaminer reliability was improved for both types of examiners with the criterion-referenced evaluation. 相似文献
997.
A 65-year-old man with spontaneous rupture of the esophagus survived with a direct suture of the esophagus 15 hours after the onset of symptoms. Endoscopic examination of the esophagus was especially of great help in determining the surgical procedure in this patient, and we want to stress the importance of prompt diagnosis and immediate surgery for this disease. 相似文献
998.
K el-Ghomari J W Gorrod 《European journal of drug metabolism and pharmacokinetics》1987,12(4):253-258
Biological oxidation of 2,4-diamino-6-substituted pyrimidines have been studied using hepatic microsomes from various mammalian species. The nature of the enzyme(s) involved in the oxidation has been elucidated using various enzyme inhibitors and inducing agents. The 3-N-oxides were formed with 6-piperidino-, 6-diethylamino-, 6-methyl-, and 6-chloro-substituted 2,4-diaminopyrimidines: no evidence of 1-N-oxide formation was obtained. With the 6-hydroxy-, 6-amino-, and unsubstituted 2,4-diaminopyrimidines and melamine, no N-oxidative metabolite was detected. The differences in N-oxide formation was discussed in terms of the effect of substituents on tautomerism and electron distribution. The N-oxygenation was mediated via a cytochrome P450 dependent system. 相似文献
999.
Clinical and hormonal effects of chronic gonadotropin-releasing hormone agonist treatment in polycystic ovarian disease 总被引:1,自引:0,他引:1
K Steingold D De Ziegler M Cedars D R Meldrum J K Lu H L Judd R J Chang 《The Journal of clinical endocrinology and metabolism》1987,65(4):773-778
Previously, we reported that short term administration of a highly potent GnRH agonist (GnRHa) for 1 month to patients with polycystic ovarian disease (PCO) resulted in complete suppression of ovarian steroidogenesis without measurable effects on adrenal steroid production. This new study was designed to evaluate the effects of long term GnRHa administration in PCO patients with respect to their hormone secretion patterns and clinical responses. Eight PCO patients and 10 ovulatory women with endometriosis were treated daily with sc injections of [D-His6-(imBzl]),Pro9-NEt]GnRH (GnRHa; 100 micrograms) for 6 months. Their results were compared to hormone values in 8 women who had undergone bilateral oophorectomies. In response to GnRHa, PCO and ovulatory women had rises of serum LH at 1 month, after which it gradually declined to baseline. In both groups FSH secretion was suppressed throughout treatment. Serum estradiol, estrone, progesterone, 17-hydroxyprogesterone, androstenedione, and testosterone levels markedly decreased to values found in oophorectomized women by 1 month and remained low thereafter. In contrast, serum pregnenolone and 17-hydroxypregnenolone were partially suppressed, and dehydroepiandrosterone, dehydroepiandrosterone sulfate, and cortisol levels did not change. Clinically, hyperplastic endometrial histology in three PCO patients reverted to an inactive pattern, and proliferative endometrium in two other PCO patients became inactive in one and did not change in the other. Regression of proliferative endometrial histology occurred in all ovulatory women. Vaginal bleeding occurred in all women studied during the first month of GnRHa administration, after which all but one PCO patient became amenorrheic. Hot flashes were noted by all ovulatory women and by four of eight PCO patients. All PCO patients noted subjective reduction of skin oiliness, and five had decreased hair growth. We conclude that in premenopausal women: 1) chronic GnRHa administration results in apparently complete persistent suppression of ovarian steroid secretion; 2) adrenal steroid secretion is not influenced directly or indirectly; and 3) its use may be helpful in the treatment of endometrial hyperplasia and ovarian androgen excess in women with PCO. 相似文献
1000.
N Ogata 《Brain research》1987,403(2):225-233
The action of gamma-aminobutyric acid (GABA) in the supraoptic nucleus was investigated using guinea pig brain slices. GABA produced a membrane depolarization accompanied by a decrease in the input resistance. The action of GABA was concentration-dependent throughout a wide range of concentrations (10(-7)-10(-3) M). In none of the cells examined, a membrane hyperpolarization was observed. The reversal potential for the depolarization induced by GABA was about 25 mV positive to the resting membrane potential. The amplitude of the GABA-induced depolarization was increased to 1.5 X the control by reducing the external Cl- from 134.2 mM to 10.2 mM. The action of GABA was readily antagonized by relatively low concentrations of bicuculline (10(-5) M). The action of GABA in the hippocampus or in the anterior hypothalamus was markedly different from that in the supraoptic nucleus, i.e. GABA produced both depolarizing and hyperpolarizing responses in the hippocampus and consistently a hyperpolarization in the anterior hypothalamus. The depolarizing but not the hyperpolarizing response in the hippocampus was selectively blocked by picrotoxin (2 X 10(-5) M) or by bicuculline (10(-5) M). The depolarizing component was dependent on the external Cl- concentration and had a reversal potential similar to that of the depolarization induced by GABA in the supraoptic nucleus. The hyperpolarizing component was resistant to bicuculline and had a reversal potential about 30 mV negative to the resting membrane potential.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献