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41.
PURPOSE: We determine the effect of long-term suppression of dihydrotestosterone with finasteride, a specific type II 5alpha-reductase inhibitor, on bone mineral density. MATERIALS AND METHODS: As part of a large (3,040 cases) 4-year, double-blind, placebo controlled trial designed to assess the long-term effects of finasteride in men with benign prostatic hyperplasia, 157 men 46 to 76 years old who were randomized to receive either 5 mg. finasteride or placebo underwent dual energy x-ray absorptiometry of the lumbar spine at baseline and at years 2, 3 and 4. RESULTS: Of 117 patients who had a baseline measurement and at least 1 additional measurement during the study baseline mean plus or minus standard deviation bone mineral density values were 1.12 +/- 0.17 gm./cm.2 in the finasteride group (63) and 1.10 +/- 0.17 gm./cm.2 in the placebo group (54). After 4 years bone mineral density was not different between treatment groups (finasteride 1.14 +/- 0.17 gm./cm.2 and placebo 1.13 +/- 0.18 gm./cm.2). Similar results were obtained for the 33 finasteride and 25 placebo treated patients who completed the study with year 4 bone mineral density measurements. CONCLUSIONS: These data demonstrate that long-term inhibition of type II 5alpha-reductase with finasteride does not adversely affect bone mineral density.  相似文献   
42.
There is a paucity of data regarding sexuality among nursing home residents. The aim of the present study was to evaluate sexual attitudes in a group of independent residents in a large urban nursing home. Ten items covering different aspects of sexual attitude were scored by two board certified psychiatrists following a semistructured interview. The study was undertaken at a large 1,200-bed nursing home providing services to both healthy independent elderly as well as geriatric patients. Subjects were 31 volunteers: 15 men and 16 women (mean age: 82.4 and 74.1 years, respectively), who consented to participate. Participants were cognitively intact and living independently at the nursing home. Exclusion criteria were: a) current major psychiatric morbidity, b) drug or alcohol abuse, c) Geriatric Depression Scale (short version) score 5, and d) Clinical Dementia Rating >0. A hierarchy of basic functions was constructed wherein each function was graded on a 5-point Likert-like scale reflecting its endorsed importance. The majority (23/31) felt that sexuality should be openly discussed with the elderly by health professionals. Twenty-one of 31 expressed willingness to receive medical consultation and treatment for sexual dysfunction as needed and 20/31 expressed a similar attitude if their partner so needed. The hierarchy of needs was rated by the participants (men and women, respectively) as follows: Mood (4.4; 4.3), Memory (4.2; 4.2), Sleep (3.8; 3.9), Sex (3.5; 2.8), and Appetite (2.8; 2.6). Sex is graded as moderately important among nursing home residents, more so in males. The majority of residents expressed positive attitudes towards open discussion of sexual matters and willingness to accept therapeutic interventions when needed.  相似文献   
43.
Suicide is a major public health problem with advancing age being one of the factors associated with increased risk. It has been suggested that most DSM axis-I disorders contribute to increased suicidal risk while dementia is one of the few exceptions. We conducted a 10-year retrospective analysis of all elderly patients suffering from dementia admitted to a large urban mental health center. Between 1991 and 2000 there were 1,551 admissions to our center who were 65 years or older. Of these, 341 were diagnosed (DSM-IV criteria) as suffering from dementia and 215/341 as suffering from Alzheimer's disease (AD). Sixteen AD patients (7.4% of all AD patients) were admitted immediately following a suicide attempt. The control group consisted of the next admission of an elderly AD patient matched for age and gender. The index group (suicidal patients) differed from controls in Clinical Dementia Rating scores (p = 0.017) and higher frequency of previous suicide attempts (p = 0.022). Lifetime psychopathology was not associated with higher rates of suicide attempts (p = 0.068). Physicians should be aware that suicide attempts are not rare in elderly AD patients. Higher level of daily functioning and previous suicide attempts are associated with increased suicidal risk.  相似文献   
44.
45.
The present study describes a new in vivo animal model that enables the detection of cerebrospinal fluid (CSF) leakage after dural injury. A polyethylene catheter (PE 10) was inserted into the subarachnoid space in the lumbar area by a simple surgical procedure and a radioactive isotope Tc99m Macroaggregated Albumin (Tc99m MAA) was injected into the CSF. In the experimental group, a standardised dural puncture was performed in the cervical area. The accumulation of the isotope in the gauze placed over the dural puncture and viewed by a gamma camera as a spot of concentrated radioactivity, was indicative of CSF leakage. In a second group of animals with intact cervical dura the absence of leakage was presented as a picture of sporadic background radioactivity. To demonstrate the effectiveness of the model in detection of invisible leakage, blood was applied over the cervical dural defect in another group of animals and CSF leakage was assessed by the above mentioned isotope detection method. This in vivo model may be used for evaluation of the sealing properties of various materials under physiological and metabolic processes in living tissue.  相似文献   
46.
47.
BACKGROUND AND OBJECTIVE: To compare the results of combined pars plana vitrectomy and cataract extraction with intraocular lens implantation by phacoemulsification versus manual extracapsular cataract extraction through a sclerocorneal tunnel. PATIENTS AND METHODS: Retrospective chart review of all patients who underwent combined pars plana vitrectomy with intraocular lens implantation and phacoemulsification or extracapsular cataract extraction through a sclerocorneal tunnel between March 1992 and July 2002. RESULTS: Fifty-four eyes of 51 patients were evaluated. Mean age was 69.68 +/- 9.11 years, and mean follow-up was 9 months. Phacoemulsification was performed in 35 cases (64%) and manual extraction in 19 cases (36%). Visual acuity improved from mean logarithm of the minimal angle of resolution 1.69 +/- 0.54 before surgery to 1.22 +/- 0.76 after surgery. There was a greater improvement of visual acuity in the phacoemulsification group (0.59 +/- 0.67) than in the extracapsular cataract extraction group (0.22 +/- 0.68) (P = .06). Final visual acuity was correlated to the vitreoretinal pathology. Ultrasound biomicroscopy showed well-positioned foldable or rigid intraocular lens in the bag or in the sulcus. CONCLUSION: Combined cataract extraction by phacoemulsification or extracapsular cataract extraction through sclerocorneal tunnel and pars plana vitrectomy are safe and effective procedures.  相似文献   
48.
BACKGROUND AND OBJECTIVE: To report the outcome of combined verteporfin photodynamic therapy (PDT) and intravitreal triamcinolone acetonide (IVTA) for the treatment of choroidal neovascularization (CNV) with serous pigment epithelium detachment (PED) due to age-related macular degeneration (AMD). PATIENTS AND METHODS: The files of all consecutive patients with CNV and serous PED who received PDT and IVTA either primarily (primary treatment group) or following previous unsuccessful PDT (secondary treatment group) were reviewed for visual and angiographic results. RESULTS: Ten patients (11 eyes) were included. Mean number of PDT sessions was 3.18; 8 eyes received one IVTA injection and 3 eyes received two IVTA injections. Thirty-six percent of patients retained their initial visual acuity after a mean follow-up of 15.3 months. Loss of 3 or more Snellen lines was noted in 2 of 3 eyes in the primary treatment group and 5 of 8 eyes in the secondary treatment group. Increased intraocular pressure developed in 3 patients and was controlled by topical medications. CONCLUSIONS: Although combined PDT and IVTA may be considered for CNV with serous PED in patients with poor prognosis with PDT alone, the regimen as administered in this small series was not beneficial. Further studies are required to determine whether alternate sequences, timing, or doses would yield a better outcome.  相似文献   
49.
Burkitt's-lymphoma (BL) lines which have maintained in vitro the tumor-cell phenotype (group-1 BLs) are poor antigen- presenting cells (APC), in spite of a relatively high surface expression of MHC class II. In order to investigate the mechanism of this deficiency, we have compared group-1 BL lines, their sub-lines which have progressed in vitro towards an LCL-like phenotype (group-III BL), and EBV-transformed lymphoblastoid cell lines (LCLs), for their ability to bind and process tetanus toxoid (TT). The uptake and internalization of 125I-labelled TT was equivalent in the 3 cell types. Only LCLs and group-III BL lines were able to process the IT,as shown by the identification of discrete proteolytic products after separation of whole-cell extracts in tricine-SDS-polyacrylamide gels, and by the recovery of TCA-soluble radioactivity in the culture supernatant. Processing of TT was induced by expression of the EBV- encoded membrane protein LMPI in transfected group-I BLs. The present findings suggest that the inability of group-I BLs to act as APC is due to their failure to process exogenous antigens. This function appears to be related to phenotypic properties that can be modulated by the expression of LMPI.  相似文献   
50.
Apoptosis induction of human myeloid leukemic cells by ultrasound exposure   总被引:50,自引:0,他引:50  
Therapeutic ultrasound (ULS) and the resulting cavitation process has been shown to induce irreversible cell damage. In this study, we wanted to further investigate the mechanism of ULS-induced cell death and to determine whether apoptosis is involved. High intensity focused pulsed ULS sonication at a frequency of 750 KHz was delivered to HL-60, K562, U937, and M1/2 leukemia cell line cultures. ULS exposure used with induction of transient cavitation in the focal area was delivered with an intensity level of 103.7 W/cm2 and 54.6 W/cm2 spatial-peak temporal-average intensity. As a control, ULS of lower intensity was delivered at 22.4 W/cm2 spatial-peak temporal-average intensity, presumably without generation of cavitation. Our results indicated that DNA damage induced by ULS cavitation did not involve generation of free radicals in the culture media. Morphological alterations observed in cells after exposure to ULS included: cell shrinkage, membrane blebbing, chromatin condensation, nuclear fragmentation, and apoptotic body formation. Apoptotic cells were evaluated by fluorescence microscopy and detected using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, which identifies DNA breaks, and by the leakage of phosphatidylserine from the inner to the outer side of the membrane layer of treated cells. Some bioeffects induced on sonicated HL-60 cells, such as inhibition of cell proliferation, DNA repair, and cell-dependent apoptosis, were found to be similar to those produced by gamma-irradiation. Thus, much of the cell damage induced by therapeutic ULS in leukemia cells surviving ULS exposure appears to occur through an apoptotic mechanism.  相似文献   
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