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41.
OBJECTIVE: The authors investigated whether the transition from licit drug use to marijuana use is determined by particular risk factors, as specified by the gateway hypothesis. They also evaluated the accuracy of the "gateway sequence" (illicit drug use following licit drugs) for predicting a diagnosis of substance use disorder. METHOD: Boys who consumed licit drugs only (N=99), boys who consumed licit drugs and then transitioned to marijuana use (gateway sequence) (N=97), and boys who used marijuana before using licit substances (alternative sequence) (N=28) were prospectively studied from ages 10-12 years through 22 years to determine whether specific factors were associated with each drug use pattern. The groups were compared on 35 variables measuring psychological, family, peer, school, and neighborhood characteristics. In addition, the utility of the gateway and alternative sequences in predicting substance use disorder was compared to assess their clinical informativeness. RESULTS: Twenty-eight (22.4%) of the participants who used marijuana did not exhibit the gateway sequence, thereby demonstrating that this pattern is not invariant in drug-using youths. Among youths who did exhibit the gateway pattern, only delinquency was more strongly related to marijuana use than licit drug use. Specific risk factors associated with transition from licit to illicit drugs were not revealed. The alternative sequence had the same accuracy for predicting substance use disorder as the gateway sequence. CONCLUSIONS: Proneness to deviancy and drug availability in the neighborhood promote marijuana use. These findings support the common liability model of substance use behavior and substance use disorder.  相似文献   
42.
Aim This prospective study was conducted to compare changes in the health‐related quality of life (HRQoL) and religious practices of patients who underwent surgery for rectal cancer. Method We prospectively followed 93 Muslim patients after surgery for colorectal carcinoma: abdominoperineal excision (APE, n = 50), sphincter‐saving resection (LAR, n = 22) or anterior resection including sigmoid colectomy (AR, n = 21). The HRQoL was measured pre‐ and postoperatively at 15–18 months with the Medical Outcomes Study Short Form 36 Health Survey (SF‐36) and a modified version of the American Society of Colorectal Surgeons (ASCRS) Fecal Incontinence questionnaire. Life standards, including religious practice, were measured using the Ankara University Life Standard Questionnaire. Results No difference was detected in any SF‐36 Health Survey HRQoL domain among the groups, although there were differences within groups before and after surgery. The ASCRS Fecal Incontinence questionnaire scales of lifestyle, coping/behaviour and depression/self‐perception were similar in the APE and AR groups and were significantly worse than in the AR group (P ≤ 0.004). The embarrassment scale was worse in the APE than in the LAR and AR groups (P < 0.001). Religious worship (praying alone, praying in mosques, fasting during Ramadan and purifying alms) was not significantly different among the groups. Conclusion HRQoL measured by the SF‐36 questionnaire and religious practices were not significantly different after APE compared with AR. Ostomy support and pre‐ and postoperative health‐related and religious counselling may have had beneficial effects.  相似文献   
43.
Chest wall involvement is an uncommon manifestation of musculoskeletal tuberculosis. We present computed tomography and magnetic resonance imaging findings in a case with multifocal musculoskeletal tuberculosis presenting as a breast mass. These radiological modalities are not diagnostic without histopathological confirmation, but they are valuable guides to surgery in defining the extent of disease involvement. Received: 1 July 1998; Revision received: 8 October 1998; Accepted: 12 October 1998  相似文献   
44.
Free-radical generation and nitric oxide (NO) generation were detected in the rat bladder following acute bladder outlet obstruction (BOO), and the results were compared with those for vascular ischemia and reperfusion (I-R). Forty male Sprague Dawley rats were used. In the acute BOO plus I-R group (group 1), rats were catheterized with a 3-Fr catheter and an inflated balloon was positioned at the bladder neck. The bladder was overdistended after administration of Ringer solution and furosemide (12 mg/kg, each) for 60 min, and was then drained to allow reperfusion for 30 min. In the acute BOO plus nerve stimulation group (group 2), the pelvic nerve was stimulated in the distended bladder for 60 min (5 s every 5 min, 10 V/0.1 ms, 20 Hz). Pelvic nerve stimulation was performed in nonobstructed animals in group 3. In the I-R group (group 4), the distal aorta was occluded for 60 min followed by reperfusion for 30 min. Sham-operated animals served as the control group (group 5). At the end of the protocols, the levels of hydroxyl and superoxide radicals and NO levels were measured in the bladder tissues with luminol- and lucigenin-enhanced chemiluminescence methods. The results were compared by a one-way analysis of variance test. The levels of hydroxyl radicals were not significantly different between the study groups. In contrast, superoxide radicals and NO levels were significantly increased in both group 1 and group 4 compared with those in control animals (P < 0.05 for all comparisons). Superoxide radical generation in group 2 was comparable to the levels in group 1 (P > 0.05), whereas NO levels were substantially lower than in group 1 (P = 0.06). In summary, vascular I-R causes significant oxidative damage to the bladder. Acute BOO with overdistension of the bladder mimics the effects of true vascular I-R injury. The NO pathway has possibly a major role in I-R-induced bladder damage. Prolonged BOO may therefore significantly enhance the oxidative damage to the bladder and further accentuate the effects of generalized atherosclerotic processes in the elderly adult.  相似文献   
45.
46.
Objective To investigate whether stone dimension is a restrictive factor for ureterorenoscopic procedures. Materials and methods A group of 416 patients who had undergone ureterorenoscopic pneumatic lithotripsy (URS-PL) for lower ureteral stones between January 1999 and June 2006 in our clinic had been evaluated retrospectively. Two hundred and seventy (270, 64.9%) patients were men and 146 (35.1%) were women. The mean age of the patients was 36.61 (±12.43) years. Patients were grouped according to stone dimension; 193 patients with stones smaller than 1 cm being group 1 and 223 patients with stones ≥1 cm in dimension being group 2. Stone-free rate, operative time and rate of complications of the groups were compared. Pearson’s correlation test, χ2 test, Fischer’s exact test and Student’s t-test were used for the statistical analysis. The p value was accepted as being meaningful if p < 0.05. Results For group 1, the mean operative time was 39.19 (±18.33) min. Proximal stone migration in five and false passage formation in three patients was observed. Three patients were stone-free after a second session of URS-PL. The cumulative stone-free rate was 97.4% (188/193). For group 2, the mean operative time was 48.5 (±11.31) min. About 208 (93.27%) patients were stone-free after the first session and an additional eight patients became stone-free after the second session of URS-PL. False passage, ureteral perforation, ureteral avulsion and stricture were observed in four, six, one and one patients, respectively. No proximal stone migration was observed. The cumulative stone-free rate was 96.86% (216/223). Conclusions The effectiveness of ureterorenoscopy (URS) in the treatment of distal ureteral stones was independent of stone dimension. However, the operative time was longer and the rate of perforation was higher in stones with a diameter ≥1 cm. On the other hand, the migration rate was higher in stones <1 cm in diameter. Generally speaking, there was no meaningful effect of stone dimension on complication rates.  相似文献   
47.
Although, one out of every eight women has a risk of developing breast cancer, the reported incidence of breast carcinoma detection in reduction mammaplasty materials is rather low. To our knowledge, specimen radiography, which is used for breast biopsies has not been used for the assessment of breast reduction materials. We investigated the applicability of specimen radiography and its potential benefits in detection of the breast pathologies, especially malignancies in reduction mammaplasty materials. Forty patients scheduled for reduction mammaplasty operation were included. In all cases an inferior pedicle reduction technique was preferred and the radiographs of the resected breast tissues were taken immediately. The radiographs were evaluated for any possible pathologic appearance and all abnormal findings were marked. For the histopathologic evaluation, in addition to the random sampling of the pathologist, any marked areas were also microscopically examined. In two cases fibrocystic changes were found in radiographs and the same results were obtained in the histological examination. No false negative mammogram was seen. Specimen radiography, which is applicable for breast reduction materials is an easy and cheap method and does not cause any patient discomfort. It seems that the radiographs of reduction mammaplasty materials are useful to provide guidance to the pathologist during tissue sampling for microscopic examination especially when large amounts of breast tissue is excised.  相似文献   
48.
Patients with erectile dysfunction, who admitted to 4 different urological centres in Turkey were evaluated in terms of aetiological factors to establish the aetiology of erectile dysfunction in our population and compare it with the data derived from Western communities. After the history, physical examination, psychological evaluation and laboratory testing, a clinical diagnosis was established as primarily psychogenic, organic, or mixed aetiology. Mean patient age was 43.5 years (range 17 to 69), and 9 of the patients were unmarried. Of the patients 53 had vascular risk factors, and 10 reported a history of alcohol abuse. Eleven patients were using drugs that might interfere with the disorder. In this multicentral study of 115 impotent men, an organic cause was found in 43%, psychogenic in 47%, and mixed in 19%. Mean age of the overall patients was 43.48. When the ages of the patients with organic erectile dysfunction and those with psychogenic erectile dysfunction were compared, it was clearly seen that those with organic erectile dysfunction were much older (52.73 versus 33.02). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
49.
Treatment of humeral shaft non-unions by the Ilizarov method   总被引:3,自引:1,他引:3  
Thirty-five humeral shaft non-unions treated by the Ilizarov external fixator were studied after an average of 39 months. Bone union was achieved in all but one. The mean time to union was 5.5 months (range: 3-10 months). Major pin tract problems leading to removal of the Schanz screws occurred in three patients. A radial nerve palsy developed in three patients, two recovered spontaneously and one was treated with a triple tendon transfer.  相似文献   
50.
Management of Esophageal Perforation   总被引:12,自引:0,他引:12  
Despite recent advances in thoracic surgery, the management of esophageal perforation remains problematical and controversial. Thirty-one patients were treated for an esophageal perforation between 1986 and 1998. The esophageal perforation was iatrogenic in 25 cases, spontaneous in 2, traumatic in 2, and caused by a tumor and tuberculous lymphadenitis in 2 patients. There were 10 cervical, 19 thoracic, and 2 abdominal perforations. The interval from perforation to operation was less than 24 h in 12 patients and more than 24 h in 19 patients. The surgical procedures included a primary repair in 12 patients, a resection in 8, and conservative treatment with minor surgical approaches in 11. The mortality rate was 20% (4/20 patients) in the surgical treatment group and 45.5% (5/11 patients) in the conservative treatment with minor surgery group. The overall mortality was 29% (9/31 patients). The prognosis is thus concluded to depend on the cause and location of the perforation, the presence of underlying esophageal diseases, and the surgical procedure chosen. Received: October 12, 1999 / Accepted: May 30, 2000  相似文献   
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