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31.
In 148 patients with impingement lesion type I or type II, we performed an arthroscopic subacromial decompression (ASD). 122 patients ran a follow up one to three years post-operatively. All patients were pre- and postoperatively documented by a 100 point shoulder score. The mean score was 57.9 (+/- 11.5) preoperatively. Postoperatively there was a significant increase to 80.7 (+/- 17.9) (p < 0.05). 15% of the patients with a postoperative score less than 70 points were determined as failures. Patients with a preoperative pain history of more than one year had a significantly worse result (79.1 +/- 8.4) compared to those patients with a preoperative course less than one year (88.8 +/- 11.6) (p < 0.05). Other significant factors were the patient's age, and calcific tendinitis, whereas sex, preoperative range of motion, muscle atrophy, and degeneration of the acromioclavicular joint did not significantly influence the result. Our results after ASD in patients with subacromial pathology without a rupture of the rotator cuff are encouraging. Therefore, ASD seems to be a reasonable alternative to open acromioplasty.  相似文献   
32.
Atherosclerosis was induced in 20 Hanford miniature swine. Subsequently, one iliac artery lesion in each of 16 pigs was stented with either a self-expanding (8 pigs) or a balloon-expanded (8 pigs) stent. Immediately after stent placement, 4 animals in each group were taken off the atherogenic diet and continued on normal chow for the remainder of the study. Four months after stents were placed, atherosclerosis and the mural changes associated with the stent were more clearly evident in the arteries of the pigs continued on the atherogenic diet. These pigs also exhibited significantly more neointimal proliferation. In addition, the arteries containing the balloon-expanded stents showed more extensive and complex intimal changes when compared with arteries with self-expanding stents. Although both stent designs were equally effective in maintaining vascular patency, the balloon-expanded stent was more traumatic to the vessel wall which resulted in a significantly greater neointimal thickness.  相似文献   
33.
In this, the second of a three-part series of articles in which we propose steps towards a comprehensive strategy for the control of HIV infection, we consider controversies relating to screening for HIV, the indications for and desirability of mandatory testing of certain groups at risk, and the place of voluntary testing in the control of HIV transmission and infection. Key recommendations are that mandatory testing of donors of blood and other vital tissues, patients on haemodialysis and haemodialysis unit staff is justified, and that children put up for adoption may require testing. We make further recommendations regarding HIV testing as a prerequisite for life insurance and recommend that voluntary testing be offered, supported by adequate pre- and post-test counselling. We consider that all health care workers should accept as their moral obligation the care and management of HIV-infected individuals, and that they should be adequately educated and skilled in such work. These recommendations were reached largely by consensus, although there were occasions when individual authors condoned recommendations with which they did not personally agree.  相似文献   
34.
Agomelatine and its therapeutic potential in the depressed patient   总被引:1,自引:1,他引:0       下载免费PDF全文
Despite advances in understanding potential disease mechanisms and in developing novel therapeutic approaches to the treatment of major depressive disorder, the disease continues to carry an enormous personal, social, and economic burden. Agomelatine represents an important opportunity to advance the treatment of depression. It is a melatonergic (MT1 and MT2) agonist and serotonergic (5HT2C) antagonist. Evidence from animal models of depression, complements emerging clinical data. In a dose range of 25–50 mg daily, agomelatine is an effective antidepressant with a very favorable side-effect profile. In particular, sleep restorative action in the absence of sedation and minimal effect on sexual function suggests that agomelatine represents a worthwhile treatment alternative for patients with major depressive disorder.  相似文献   
35.
Oxygen free radicals (OFR) are implicated in thepathogenesis of stress, chemically induced gastriclesions, and gastrointestinal injury. Theconcentration-dependent scavenging abilities of bismuthsubsalicylate (SBS), colloidal bismuth subcitrate (CBS), andselected OFR scavengers, including superoxide dismutase(SOD), catalase, mannitol, and allopurinol were examinedagainst biochemically or chemically generated superoxide anion, hydroxyl radical, andhypochlorite radical plus hypochlorous acid based on achemiluminescence assay. Furthermore, both gastric (GM)and intestinal mucosa (IM) were individually exposed in vitro to these free radical generatingsystems, and the concentration-dependent protectiveabilities of SBS and CBS against lipid peroxidation (LP)were compared with selected OFR scavengers. In addition, 24-hr fasted rats were orally treated with thenecrotizing agents 0.6 M HCl, 0.2 M NaOH, 80% ethanol,and aspirin (200 mg/kg). The extent of tissue injury inthe GM and IM was determined by assessing LP, DNA fragmentation, and membrane microviscosity.Dose- and time-dependent in vivo protective abilities ofCBS (100 mg/kg) and SBS (15 mg/kg) were also assessed.Following incubations with superoxide anion and hydroxyl radical generating systems in thepresence of 125 mg SBS/liter, approximately 47% and 61%inhibitions were observed in the chemiluminescenceresponse, respectively, while 48% and 46% inhibitions were observed with 125 mg CBS/liter. SBS andCBS exerted similar abilities towards hypochloriteradical plus hypochlorous acid. Approx. 3.1- and3.7-fold increases in LP were observed in the GM and IMof rats following oral administration of 0.6 MHCl. Pretreatment of the rats with SBS and CBS decreased0.6 M HCl-induced LP in the GM by approx. 39% and 27%,respectively, with similar decreases in LP in the IM. SBS exhibited better protectiveabilities towards 0.6 M HCl and 0.2 m NaOH-induced GMand IM injury as compared to CBS. SBS and CBS providedsimilar protection towards 80% ethanol-induced gastric injury, while CBS exerted a superior protectiveability towards aspirin-induced gastric injury. Theresults demonstrate that both SBS and CBS can scavengereactive oxygen species and prevent tissue damage produced by OFR.  相似文献   
36.
Congenital lipoid adrenal hyperplasia (lipoid CAH) is the most severe form of CAH in which the synthesis of all gonadal and adrenal cortical steroids is markedly impaired. We report here the clinical, endocrinological, and molecular analyses of two unrelated Japanese kindreds of 46,XX subjects affected with lipoid CAH who manifested spontaneous puberty. Phenotypic female infants with 46,XX karyotypes were diagnosed with lipoid CAH as newborns based on a clinical history of failure to thrive, hyperpigmentation, hyponatremia, hyperkalemia, and low basal values of serum cortisol and urinary 17-hydroxycorticosteroid and 17-ketosteroid. These patients responded to treatment with glucocorticoid and 9alpha-fludrocortisone. Spontaneous thelarche occurred in association with increased serum estradiol levels at the age of 10 and 11 yr, respectively. Pubic hair developed at the age of 12 yr 11 mo in one subject and menarche was at the age of 12 yr in both cases. Both subjects reported periodic menstrual bleeding and subsequently developed polycystic ovaries. To investigate the molecular basis of the steroidogenic lesion in these patients, the StAR gene was characterized by PCR and direct DNA sequence analyses. DNA sequence analysis revealed that one patient is homozygous for the Gln 258 Stop mutation in exon 7 and that the other patient is a compound heterozygote with the Gln 258 Stop mutation and a single A deletion at codon 238 in the other allele causing a frame-shift, which renders the StAR protein nonfunctional. These findings demonstrate that ovarian steroidogenesis can be spared to some extent through puberty when the StAR gene product is inactive. This is in marked contrast to the early onset of severe defects in testicular and adrenocortical steroidogenesis which are characteristics of this disease.  相似文献   
37.
Strauss  BS 《Carcinogenesis》1997,18(8):1445-1452
Published data on TP53 mutations can be used to examine the question of whether generalized hypermutability is a necessary condition for tumorigenesis. Although individual mutations do play an etiologic role in tumor formation, the evidence so far does not make it necessary to assume a general mutability. Silent and multiple mutations in the TP53 data set indicate that a special hypermutability process operates on this gene during the generation of tumors. The percentage of silent p53 mutations observed (3%) is at least 20 times greater than would be expected and indicates hypermutability for this gene. The greater proportion of silent mutations among multiple p53 mutations (10%) indicates that the mutations occur nonselectively. The presence of silent mutations implies that not all mutations observed in tumors have an etiologic role. Analysis of the distribution of tumors with two, three, four and more p53 mutations suggests that mutations in some tumors occur in clusters possibly as a result of 'stuttering' in DNA synthesis. It is argued that the most likely alternative explanations of the data, polymorphism and/or a selective role for silent mutations, are not correct. It remains possible that the hypermutability process is restricted to particular genes or to regions of the genome as, for example, in antibody production. There is a surprising paucity of data on human polymorphism and nucleotide diversity which makes the analysis difficult.   相似文献   
38.
New iodinated radiological contrast media, which are safer but much more expensive than the conventional ones, have been introduced. Since the financial implications are considerable a compromise between cost and safety is inevitable. It is therefore recommended that, at present, the conventional media be used routinely and the new media be reserved for potentially painful examinations and for patients at higher risk. Should a question of wrongfulness or negligence concerning the use of contrast media be considered by our courts, they will undoubtedly be influenced by what is considered 'common practice' and 'accepted practice' within a medical specialty and that may be co-determined by socio-economic considerations.  相似文献   
39.
To assess physiological and psychological states accompanying anabolic-androgenic steroid use, male weight lifters 1) were interviewed regarding their physical training and the patterns and effects of any drug use; 2) completed a written physical and medical history questionnaire, a Profile of Mood States questionnaire, and the Buss-Durkee Hostility Inventory; and 3) were physically examined, including a blood sample and urinalysis. Subjects were divided into current anabolic-androgenic steroid users (N = 12), previous users (N = 14), and nonusers (N = 24). Current and previous users reported the following changes associated with anabolic-androgenic steroid use: increases in enthusiasm, aggression, and irritability; changes in insomnia, muscle size, muscle strength and density; faster recovery from workouts and injuries; and changes in libido. We were unable to confirm these interview and physical and medical history questionnaire responses using standardized and well-accepted psychological inventories. There were no significant differences among groups for any Profile of Moods factor, total mood disturbance, total Buss-Durkee Hostility Inventory score, or any subscale. For current users, there were no significant correlations between either total weekly drug dose or length of time on the current cycle of anabolic-androgenic steroids and any individual scale of the Profile of Mood States, Buss-Durkee Hostility Inventory, Profile of Mood States total mood disturbance, or composite Buss-Durkee Hostility Inventory score. Furthermore, anabolic-androgenic steroid users did not differ in their responses on these inventories from nonusers or from general population norms.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
40.
Insulin-like growth factor I (IGF-I) synergistically amplified the stimulatory effect of low density lipoprotein (LDL) on progesterone biosynthesis by primary cultures of swine ovarian cells. The mechanisms subserving this facilitative interaction included the following. IGF-I's synergism with LDL was associated with a decrease in the mean half-maximally stimulatory concentration of LDL from 20-3.5 micrograms/ml. IGF-I increased by 3- to 6-fold the number of specific high affinity LDL receptors on ovarian cells, with no change in apparent binding affinity. IGF-I augmented by 3- and 18-fold the maximal rates of [125I]iodo-LDL internalization and degradation, respectively, without altering half-maximally effective concentrations of LDL supporting these processes. IGF-I increased by 2- to 2.5-fold the total mass of free and esterified cholesterol contained in granulosa cells. IGF-I stimulated the intracellular accumulation of free [3H]cholesterol and [3H]cholesteryl ester from exogenous [3H]cholesteryl linoleate-labeled LDL, and amplified [3H]progesterone secretion by granulosa cells exposed to this source of lipoprotein-borne sterol. These actions of IGF-I were demonstrated at 30- to 100-fold lower concentrations of IGF-I than insulin. We conclude that IGF-I and LDL synergistically enhance progesterone biosynthesis by ovarian cells. This synergism occurs in part via mechanisms that regulate the effectual delivery of lipoprotein-borne cholesterol substrate into cellular sterol pools that participate in steroid hormone biosynthesis.  相似文献   
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