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991.
The synthesis of (6R,5S,2RS)-6-amino-5-hydroxy-2-isobutyl-4-oxo-7- phenylheptanoic acid (9), a carbaanalogue of the aminopeptidase (AP) inhibitor bestatin (1) is described. This synthesis was carried out by a malonic ester alkylation with the suitably protected halomethyl ketone of (2S,3R)-AHPBA*), followed by a second alkylation with isobutyl bromide of the resulting 4-ketodiester, and subsequent decarboxylation and deprotection. The inhibitory potencies of the 1:1 diastereomeric mixture 9 against AP-B, AP-M and Leu-AP were approximately 10-fold lower than those of bestatin.  相似文献   
992.
A normal gonadal maturation with normal fertility are some of the major goals of long-term replacement therapy in adult males with Congenital Adrenal Hyperplasia (CAH). We describe here two young men, G.O. (case A, 23 years old) and S.S.(case B, 24 years old), both with a well defined diagnosis of CAH due to 21-hydroxylase deficiency classic homozygote form (21-CAH). In case A the diagnosis of the 21-CAH classic virilizing form was made at 3 years of age. The patient has undergone glucocorticoid therapy and is now 170 cm tall; all his hormonal findings are within the normal range. The semen analysis has shown a good fertility potential, with a slight modification when the patient decided to discontinue the therapy. In case B the diagnosis of the 21-CAH salt wasting form was performed at 9 days of age. The patient was initially treated with i.v. normal saline solution and a daily i.m. injection of hydrocortisone and, subsequently, with mineral and glucocorticoid replacement therapy po. A satisfactory adult stature (165 cm) was attained. The patient is still on therapy, with a good hormonal profile. The semen analysis has shown an apparently normal fertility. In conclusion, our experience in adult males with 21-CAH, who have been administered prompt and adequate replacement therapy, shows that these patients can attain normal quality of life, satisfactory growth and development, normal sexual maturation and activity, and adequate sperm fertilizing ability, thereby supporting the usefulness of continuing this therapy during adult age.  相似文献   
993.
994.
Placement of internal ureteral stents for internal urinary diversion and prevention of urological complications has been well established. However, indwelling stents have occasionally been associated with patient morbidity and intolerance. A total of 255 patients while the internal ureteral stent had been used were analyzed. The symptoms including urinary frequency (42.0%), hematuria (41.6%) and suprapubic pain (20.4%), loin pain (17.3%) and micturition pain (16.9%) accounted for the major complaints of the stent indwelling patients. The major complications, i.e. stent migration, heavy encrustation, pyelonephritis, fragmentation, intolerance and penetration of collecting structure, were occasionally observed. These complications increase secondary morbidity in patients. The double-J stents should be used carefully with regard to the prevention and treatment of untoward conditions as early as possible.  相似文献   
995.
Trained nurse practitioners can insert the contraceptive implant system Norplant. Courts may call on nurse practitioners to insert Norplant in poor women. Legislative and prosecutorial initiatives to coerce low-income women and female parolees to use contraceptives should not become law. Offering incentives to poor women is another form of involuntary fertility control. Eugenics and the sterilization campaign of the past form the basis for judicial and legislative initiatives to coerce women to accept Norplant. Providers have inserted Norplant in women from other countries without the women knowing the side effects. Often medical personnel do not remove Norplant when women request its removal. Nurses have historically played a public policy role in reproductive rights. They have promoted procreative rights through their roles as educators/counselors, advocators, empowerers, and practitioners. Nursing's power and expertise help protect against punitive government intrusion in reproductive rights and make sure that contraceptive breakthroughs (e.g., Norplant) strengthen procreative choices. They can guide the development of sound public policy. Norplant is not the answer to poverty, child abuse, or drug abuse. Nursing research can help policymakers become more responsive to the contraceptive and reproductive rights of everyone.  相似文献   
996.
Phase I and II activities were examined in six rodent hepatoma cell lines and compared with those of cultured rat hepatocytes both in basal conditions and after exposure to 5 microM methylcholanthrene, 2 mM phenobarbital, and 15 microM beta-naphtoflavone. The metabolic profile of testosterone was also studied. The highest aryl hydrocarbon hydroxylase and 7-ethoxycoumarin O-deethylase activities were found in MH1C1 cells. Comparable values for 7-ethoxyresorufin O-deethylase activity, ranging from 21.6 to 42.9 pmol/mg x min, were observed in the hepatocytes and hepatoma cells, except the HTC cells. In contrast, only Fao cells showed 7-pentoxyresorufin O-depentylase activity at levels similar to those of hepatocytes (6.2 +/- 1.0 and 7.4 +/- 1.2 pmol/mg x min, respectively). Rat hepatocytes actively hydroxylated p-nitrophenol, but this activity was not measurable in hepatoma cells. Glutathione transferase activity was maintained in all the hepatoma cell lines at similar levels to those found in hepatocytes (684 +/- 56 nmol/mg x min). The seven hydroxylated metabolites of testosterone produced by cultured hepatocytes were negligible in hepatoma cells. Exposure of cells to inducers revealed that aryl hydrocarbon hydroxylase activity was mainly increased after treatment with 3-methylcholanthrene and beta-naphtoflavone, and the highest values were found in rat hepatocytes followed by MH1C1 and Fao cells. 3-Methylcholanthrene and naphtoflavone treatment also resulted in a marked increase in 7-ethoxyresorufin O-deethylase activity in hepatocytes as well as in H4IIC3, McA-Rh7777, MH1C1, and Fao cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
997.
BACKGROUND: Preclinical study and human patch tests indicate polyolprepolymer-2 may reduce cutaneous tretinoin-induced irritation. OBJECTIVE: This study compared the clinical efficacy and safety of a 0.025% tretinoin cream containing polyolprepolymer-2 and its vehicle to a commercially-available 0.025% tretinoin cream. METHODS: In this 12-week multicenter, double-blind, parallel group study in patients with mild to moderate acne, objective lesion counts and the investigators' global evaluations evaluated efficacy. Subjective evaluations of skin irritation were used to study safety. RESULTS: A total of 271 patients were enrolled. The active treatments demonstrated comparable efficacy that was statistically significantly greater than that of the vehicle. Safety evaluations of cutaneous and noncutaneous adverse events also indicated comparable results of the active treatments. CONCLUSION: The commercially-available 0.025% tretinoin cream and the 0.025% tretinoin cream containing polyolprepolymer-2 demonstrated comparable efficacy and safety.  相似文献   
998.
Chlorpromazine (CPZ) has been previously shown to protect against endotoxin [lipopolysaccharide (LPS)] lethality and inhibit the release of tumour necrosis factor in vivo. We investigated at the cellular level whether this was due to direct inhibition of tumour necrosis factor-alpha (TNF-alpha) synthesis, using LPS-stimulated THP-1 human monocytic leukemia cells. We also studied the effect of CPZ on human TNF-alpha action by assessing TNF-alpha cytotoxicity on mouse fibrosarcoma L929 cells. CPZ (1-100 microM) inhibited TNF-alpha production in THP-1 cells in a dose dependent manner by a maximum of 80%. This effect was comparable to that of two well-known inhibitory drugs, dexamethasone and cyclicAMP. Inhibition was also evident at the mRNA level. On the other hand CPZ (10-25 microM) also inhibited TNF-alpha activity: in fact it reduced the cytotoxicity of TNF-alpha on L929 cells (EC50 was increased four times) and could provide protection even as a post-treatment. CPZ inhibited TNF-induced apoptosis in L929 cells, as detected by analysis of nuclear morphology. However, since we showed that apoptosis was very limited, and was not the main mode of cell death in our conditions, this could not explain the overall protection. Since CPZ did not interfere with either the oligomerization state of TNF-alpha or its receptor binding, our data suggest that it reduced cytotoxicity by inhibiting some steps in the TNF-alpha signalling pathways.  相似文献   
999.
1000.
Trauma, dissociation, and somatization: a self-psychological perspective   总被引:1,自引:0,他引:1  
Surgeon-interpreted diagnostic ultrasound has become the preferred screening test and often the definitive test for the diagnosis of arterial stenosis, aneurysm, and venous thrombosis. As a modality for surveillance, its noninvasive quality makes it particularly appealing as the test of choice to screen patients for abdominal aortic aneurysms or to perform follow-up examinations on those patients with a carotid endartectomy or in situ bypass grafts. The increasing reliance on intraoperative duplex imaging of vascular procedures demands that the surgeon learn the skills to perform the studies without a technologist or radiologist to interpret the examination.  相似文献   
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