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991.
Why do we continue to determine α‐glucosidase in human semen?* 总被引:2,自引:0,他引:2
992.
Purpose. To study the delivery efficiency of procaterol aerosols administered through the tracheal tube (ETT) with a metered-dose
inhaler (MDI) during apnea.
Methods. First, in a normal room air environment (at ambient temperatures of 24° to 26°C), we measured the amount of aerosol delivered
through the ETT by comparing the weight of a 2-l bottle before and after firing the MDI directly into the 15-mm adapter of
the ETT. The distal half of the ETT was inserted in the bottle. This procedure was repeated using five different ETTs with
an internal diameter of 4–8.5 mm. The delivery efficiency was obtained by dividing the amount of aerosol delivered through
the ETT by the total aerosol output per MDI puff. Next, we investigated whether the connector attached to the 15-mm ETT adapter
could reduce the delivery, by repeating the same procedure with 4-mm and 5-mm ETTs. Finally, we compared the efficiencies
of aerosol delivery through the 5-mm ETT and the 7.5-mm ETT in a normal room air environment with results obtained under a
humidified condition (100% humid air at 37°C).
Results. The percentages of aerosol delivered through the ETTs in a normal room air environment were 40%–60%, except for the 4-mm
ETT, for which the percentage was 32.7% ± 6.6% (P < 0.05 vs that with the 5-mm ETT or the 6-mm ETT). A connector attached to the 15-mm ETT adapter significantly decreased the delivery
efficiencies (19.0% ± 5.8% vs 32.7% ± 6.6% with the 4-mm ETT, 24.6% ± 11.8% vs 51.7% ± 10.8% in the 5-mm ETT) when compared with those without a connector. The delivery efficiencies under the humidified
condition in the 5-mm ETT and the 7.5-mm ETT were 65.5% (P < 0.05) and 89.8% of those in the normal room air environment, respectively.
Conclusion. The efficiency of delivery of procaterol aerosol through the ETTs was unexpectedly high (approximately half of the total
aerosol output per MDI puff in the 5-mm to 8.5-mm ETTs, and one third of the total aerosol output per MDI puff in the 4-mm
ETT). A connector attached to the 15-mm ETT adapter noticeably decreased the delivery efficiency. In the smaller-sized ETT,
delivery efficiency was significantly lower under the humidified condition than in the normal room air environment.
Received: September 28, 2001 / Accepted: June 24, 2002
Address correspondence to: T. Takaya 相似文献
993.
Laparoscopic management of common bile duct stones: transcystic approach and choledochotomy 总被引:25,自引:0,他引:25
Tokumura H Umezawa A Cao H Sakamoto N Imaoka Y Ouchi A Yamamoto K 《Journal of Hepato-Biliary-Pancreatic Surgery》2002,9(2):206-212
The purpose of this study was to review our experience with laparoscopic common bile duct (CBD) exploration by the transcystic
approach and choledochotomy. We selected the transcystic approach for patients whose CBD stones were less than five in number
and smaller than 9 mm in diameter, and whose CBD was less than 15 mm in diameter on cholangiograms. Among 217 patients with
CBD stones treated laparoscopically, the transcystic approach was performed successfully in 91 of 104 patients in whom it
was attempted (87.5%). The other 126 patients underwent laparoscopic choledochotomy, followed by ductal closure with transcystic
drainage in 59, T-tube drainage in 46, primary ductal closure in 19, and choledochoduodenostomy in 1. Choledochotomy was converted
to open surgery in only 1 patient. The transcystic approach was associated with shorter hospital stay and less morbidity than
choledochotomy. However, choledochotomy also had an acceptably low rate of complications. Bile leaks occurred more frequently
in those with primary ductal closure than in those with transcystic drainage or T-tube drainage. Residual stones were found
in 2 patients with the transcystic approach and in 10 with choledochotomy. The residual stones were removed through the T-tube
tract by choledochoscopy in 7 of these 10 patients. From these results we conclude that laparoscopic management of CBD stones
is feasible for almost all patients with CBD stones. It is considered to be safe and effective and has the advantage of being
a single-stage procedure.
Received: July 7, 2000 / Accepted: October 26, 2000 相似文献
994.
目的 了解妇幼卫生人员、婚检妇女和孕妇对孕前和孕早期服用叶酸预防神经管畸形的知识掌握程度及相关行为。 方法 根据不同的对象自行设计知识和行为调查问卷,由妇幼卫生人员、婚检妇女和孕妇自己填写,将结果进行x2检验和方差分析。 结果 76.7%(155/202)的妇幼卫生人员知道服用叶酸可以减少神经管畸形的发生,26.7%(54/202)的知道叶酸应当从孕前开始服用,仅有5.9%(12/202)的人知道叶酸每天摄入的适当量是0.4 mg-1 mg,34.7%(70/202)的妇幼卫生人员推荐的剂量大于1 mg;194名婚检妇女仅4人(2.1%)知道叶酸可以预防胎儿畸形,4人在服用叶酸增补剂,2人知道要从孕前服用;31.9%(67/210)的孕妇知道叶酸与神经管畸形的关系,16.2%(34/210)知道应从孕前服用,14.3%(30/210)孕妇在服用叶酸增补剂,仅4人(1.9%)真正从孕前开始服用。 结论 妇女增补叶酸预防神经管畸形的知识还没有得到很好的普及,叶酸的服用率低。建议培训妇幼人员(特别是县乡级人员)正确指导妇女应用叶酸的知识和能力,加大婚前教育宣传力度,增加服用叶酸预防神经管畸形知识的知晓率。 相似文献
995.
996.
M.J. Postma J. Londeman M. Veenstra L.T.W. de Jong-van den Berg H.E.K. de Walle 《Pharmacy World & Science》2002,24(1):8-11
Background: Supplementation of folic acid prior to and in the beginning of pregnancy may prevent neural tube defects (NTDs) in newborns – such as spina bifida – and possibly other congenital malformations.Objective: To estimate cost effectiveness of periconceptional supplementation of folic acid using pharmacoeconomic model calculation.Method: Probabilities for NTDs, risk reductions through periconceptional supplementation of folic acid and lifetime costs of care for children with spina bifida were estimated using Dutch registrations and international literature.Main outcome measure: Cost effectiveness was expressed in net costs per discounted lifeyear gained. Cost effectiveness was calculated in the baseline and in sensitivity analysis.Results: Estimated cost effectiveness of periconceptional supplementation of folic acid amounts to NLG 3900(D1800) in the base case. In sensitivity analysis cost effectiveness mostly remains below NLG 10.000(D4500).Conclusion: Periconceptional supplementation of folic acid shows a favorable cost effectiveness. From pharmacoeconomic point of view this justifies further stimulation of folicacid supplementation prior to pregnancy. This can be done through targeted education by healthcare workers, such as pharmacists. 相似文献
997.
PURPOSE: We determined whether testicular histology in men with spermatogenic failure due to nonobstructive azoospermia shows true Leydig cell hyperplasia. MATERIALS AND METHODS: Testicular biopsy specimens from 17 patients evaluated for infertility were retrospectively analyzed. Interstitial, tubular and Leydig cell volume were quantitatively evaluated. The total volume and number of Leydig cells per testicle were then calculated. RESULTS: In 10 patients with obstructive azoospermia testicular histology showed normal spermatogenic function, while 7 had nonobstructive azoospermia. Average testicular volume plus or minus standard deviation was significantly larger in those with obstructive versus nonobstructive azoospermia (18.0 +/- 7.0 versus 9.3 +/- 8.7 cc, p = 0.025). Interstitial versus tubular volume was 32% of the total testis in the obstructive and 63% in the nonobstructive groups (p = 0.003). Although Leydig cell volume was proportionally greater in men with nonobstructive versus obstructive azoospermia (13.3% versus 0.05%, p = 0.045), there was no significant difference in the average number of Leydig cells per testicle (3.96 x 10 and 6.17 x 10, respectively, p = 0.16). The average volume of individual Leydig cells was significantly greater in men with the nonobstructive condition (253.0 +/- 98.7 versus 174.0 +/- 57.7 microm., p = 0.045). CONCLUSIONS: These results suggest that men with nonobstructive azoospermia and those with normal spermatogenesis have an equivalent number of Leydig cells. However, the Leydig cells are hypertrophic and occupy a larger proportion of total testis volume in men with nonobstructive azoospermia. Therefore, patients with spermatogenic failure show Leydig cell hypertrophy but not hyperplasia. 相似文献
998.
Purpose
We studied the effect of varicocele ligation on Kruger strict morphology criteria and semen parameters in patients with infertility.Materials and Methods
A total of 90 patients diagnosed with varicoceles and a normal morphological sperm ratio of less than 14% were evaluated before and 6 months after varicocelectomy. Preoperatively and postoperatively sperm density, motility and morphology using Kruger strict criteria were analyzed. The Wilcoxon test was used to measure levels of statistical significance in all analyses.Results
Significant improvement in sperm concentration and motility was evident after varicocele ligation (p <0.0002 and <0.0001, respectively). Using the Kruger classification sperm morphology evaluation revealed a significant increase in the percent of normal forms, and of forms with head and acrosome defects (p <0.0001, <0.0014 and <0.0028, respectively). There were no concomitant changes in strict morphology in forms with mid piece and tail defects or immature forms (p >0.05). Of the 90 patients 18 (20%) achieved a successful full-term pregnancy, including 14 via natural cycle intercourse and 4 by intrauterine insemination.Conclusions
Surgical correction of varicocele was associated with significant improvement in density, motility and sperm morphology evaluated using the Kruger classification. 相似文献999.
Best practice policies for male infertility 总被引:8,自引:0,他引:8
1000.
Can varicocelectomy significantly change the way couples use assisted reproductive technologies? 总被引:4,自引:0,他引:4
Cayan S Erdemir F Ozbey I Turek PJ Kadioğlu A Tellaloğlu S 《The Journal of urology》2002,167(4):1749-1752
PURPOSE: We assessed how varicocelectomy alters semen quality in a large cohort of infertile men and determined whether it can change patient candidacy for assisted reproductive technology procedures. MATERIALS AND METHODS: A cohort of 540 infertile men with clinical palpable varicocele underwent microsurgical varicocelectomy and were followed more than 1 and 2 years postoperatively for alterations in semen quality and conception, respectively. Preoperatively and postoperatively the total motile sperm count was calculated in all semen analyses. Based on total motile sperm count values patients were divided into 4 groups according to the type of assisted reproductive technology for which they qualified, including 0 to 1.5 million or less (intracytoplasmic sperm injection candidates), 1.5 to 5 million or less (in vitro fertilization candidates), 5 to less than 20 million (intrauterine insemination candidates) and 20 million or greater sperm (spontaneous pregnancy candidates). Preoperative and postoperative semen quality was compared among individuals in these cohorts to determine the shifts in assisted reproductive technology care that are possible after varicolectomy. RESULTS: Mean patient age was 29.5 years (range 18 to 58). Microsurgical varicocelectomy was bilateral in 393 patients (73%), on the left side in 146 (27%) and on the right side in 1 (0.2%). A positive response to varicocelectomy, defined as a greater than 50% increase in total motile sperm count, was observed in 271 patients (50%). An overall spontaneous pregnancy rate of 36.6% was achieved after varicocelectomy with a mean time to conception of 7 months (range 1 to 19). Of preoperative in vitro fertilization and intracytoplasmic sperm injection candidates 31% became intrauterine insemination or spontaneous pregnancy candidates after varicolectomy. Of intrauterine insemination candidates 42% gained the potential for spontaneous pregnancy. CONCLUSIONS: Varicocelectomy has significant potential not only to obviate the need for assisted reproductive technology, but also to down stage or shift the level of assisted reproductive technology needed to bypass male factor infertility. 相似文献