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排序方式: 共有9953条查询结果,搜索用时 31 毫秒
991.
Semen quality and reproductive hormones before orchiectomy in men with testicular cancer. 总被引:2,自引:0,他引:2
P M Petersen N E Skakkebaek K Vistisen M R?rth A Giwercman 《Journal of clinical oncology》1999,17(3):941-947
PURPOSE: To obtain information about preorchiectomy gonadal function in patients with testicular germ cell cancer to improve the clinical management of fertility and other andrologic aspects in these men. PATIENTS AND METHODS: In group 1, a group of 83 consecutive patients with testicular germ cell cancer (TGCC) investigated before orchiectomy, semen analysis was carried out in 63 patients and hormonal investigations, including measurement of follicle-stimulating hormone, luteinizing hormone (LH), testosterone, estradiol, sex hormone-binding globulin (SHBG), inhibin B, and human chorionic gonadotropin (hCG), in 71 patients. Hormone levels in patients with elevated hCG (n = 41) were analyzed separately. To discriminate between general cancer effects and specific effects associated with TGCC, the same analyses were carried out in a group of 45 consecutive male patients with malignant lymphoma (group 2). Group 3 comprised 141 men employed in a Danish company who served as controls in the comparison of semen parameters. As a control group in hormone investigations, 193 men were selected randomly from the Danish National Personal Register to make up group 4. RESULTS: We found significantly lower sperm concentration (median, 15 x 10(6)/mL; range, 0 to 128 x 10(6)/mL) and total sperm count (median, 29 x 10(6)/mL; range, 0 to 589 x 10(6)) in patients with testicular cancer than in patients with malignant lymphomas (sperm concentration: median, 48 x 10(6)/mL; range, 0.04 to 250 x 10(6)/mL; sperm count: median, 146 x 10(6); range, 0.05 to 418 x 10(6)) (P < .001 and P < .001) and healthy men (sperm concentration: median, 48 x 10(6)/mL; range, 0 to 402 x 10(6)/mL; sperm count: median, 162 x 10(6); range, 0 to 1253 x 10(6)) (P < .001 and P < .001). FSH levels were increased in men with testicular cancer (median, 5.7 IU/L; range, 2.0 to 27 IU/L) compared with both men with malignant lymphomas (median, 3.3 IU/L; range, 1.01 to 12.0 IU/L) and healthy controls (median, 4.1 IU/L; range, 1.04 to 21 IU/L)(P = .001 and P = .007, respectively). Surprisingly, we found significantly lower LH in the group of men with TGCC (median, 3.6 IU/L; range, 1.12 to 11.9 IU/L) than in healthy men (median, 4.7 IU/L; range, 1.3 to 11.9 IU/L) (P = .01). We could not detect any differences between men with testicular cancer and men with malignant lymphomas and healthy men with regard to serum levels of testosterone, SHBG, and estradiol. Men with testicular cancer who had increased hCG levels had significantly lower LH and significantly higher testosterone and estradiol than those without detectable hCG levels. CONCLUSION: Spermatogenesis is already impaired in men with testicular cancer before orchiectomy. Neither local suppression of spermatogenesis by tumor pressure nor a general cancer effect seems to fully explain this impairment. The most likely explanation is preexisting impairment of spermatogenesis in the contralateral testis in men with testicular cancer. The question of whether also a pre-existing Leydig cell dysfunction is present in men with testicular cancer could not be answered in this study because the tumor seems to have a direct effect on the Leydig cells. Men with testicular cancer had low LH values as compared with controls. We speculate that increased intratesticular level of hCG also in men without measurable serum hCG may play a role by exerting LH-like effects on the Leydig cells, causing increased testosterone and estrogen levels and low LH values in the blood. 相似文献
992.
N Kjaergaard J F M?ller-Petersen F V Kristiansen P L Petersen S Ekelund P Skovbo 《Danish medical bulletin》1990,37(6):559-560
Xanthine and hypoxanthine are indicators of cellular hypoxia. The purpose of our study was to establish a reference range for the concentrations of xanthine and hypoxanthine in amniotic fluid. Of a total of 38 included in the investigation, 27 pregnant women were found to have low values for xanthine (less than 1.2 mumol/l) and hypoxanthine (less than 0.4 mumol/l). To our knowledge, this is the first attempt to define a reference range for xanthine and hypoxanthine concentration in amniotic fluid during pregnancy. 相似文献
993.
S M Essig W Mittenberg R S Petersen S Strauman J T Cooper 《Archives of clinical neuropsychology》2001,16(3):271-291
Members of the National Academy of Neuropsychology and the Association of Trial Lawyers of America were surveyed concerning current practices in forensic neuropsychology. The majority of neuropsychologists and attorneys reported that attorneys never observe neuropsychological testing. Attorneys reported receiving raw data in almost all of their brain injury cases, but neuropsychologists reported that they produce raw data in only a minority of their forensic cases. Similarly, fewer neuropsychologists than attorneys acknowledged that they are asked to provide information to assist the lawyer in preparing for the cross-examination of the opposition's expert or to prepare the plaintiff for the opposition's evaluation. Lawyers typically spend up to an hour preparing their clients for neuropsychological evaluations and commonly cover test content, detection of malingering, and brain injury symptoms. Other topics addressed include attorney influence on findings, fees and billing, board certification, use of technicians, and methods used to generate referrals or locate experts. Areas of agreement and divergence between the groups were identified and ethical issues raised by identified practices were examined. 相似文献
994.
Leesa Galatz Stefan Rothermich Kristin VanderPloeg Bryan Petersen Linda Sandell Stavros Thomopoulos 《Journal of orthopaedic research》2007,25(12):1621-1628
The adult healing response of the rotator cuff tendon‐to‐bone insertion site differs from the ordered process of insertion site development. Healing is characterized by disorganized scar and a lack of fibrocartilage formation, in contrast to the well organized fibrocartilaginous transition which forms during the normal development of the tendon‐to‐bone insertion. The purpose of this study was to localize the expression of a number of extracellular matrix and growth factor genes during insertion site development in order to guide future strategies for augmenting adult rotator cuff healing. The rotator cuff was morphologically distinct at 13.5 dpc (days postconception). Neo‐tendon was evident as a condensation of cells adjacent to bone. The interface between tendon and bone did not form into a mature fibrocartilaginous insertion until 21‐days postnatally, based upon the appearance of four distinct zones with a mineralized humeral head. Fibroblasts of the supraspinatus tendon expressed type I collagen at all timepoints. Type II collagen was first expressed by chondrocytes in the fibrocartilage and mineralized fibrocartilage at 7 days and persisted in the mineralized fibrocartilage at 56 days. Type X collagen was first expressed by the chondrocytes in the mineralized fibrocartilage at 14 days and persisted in the mineralized fibrocartilage at 56 days. A shift from TGF‐β3 to TGF‐β1 expression occurred at 15.5 dpc. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1621–1628, 2007 相似文献
995.
996.
We evaluated memory function in a group of 161 community-dwelling, cognitively normal individuals aged 62 to 100 years recruited as part of the Mayo Clinic Alzheimer's Disease Patient Registry. We used the Free and Cued Selective Reminding Test and the Rey Auditory Verbal Learning Test to evaluate two aspects of memory function thought to be sensitive to the effects of aging: learning (acquisition) and delayed recall (forgetting). The results were quite consistent and demonstrated that learning or acquisition performance declines uniformly with increasing age but is not related to education. Delayed recall or forgetting, however, remained relatively stable across age when adjusted for the amount of material initially learned. These findings are relevant for assessing normal memory function relative to the early impairments found in dementia and form a baseline against which memory performance can be assessed by the clinician. In particular, suspicion regarding a disorder of brain function affecting memory processes should be raised if learning performance declines more rapidly than expected or if delayed recall is impaired to any significant extent. 相似文献
997.
R C Petersen 《Postgraduate medicine》1992,92(8):141-148
Acute confusional state is a condition that is commonly encountered in many types of medical practice. Certain patients, especially the elderly, are vulnerable to the disorder, and recognition of this fact can help prevent the development or minimize the severity of the condition. Thorough history taking and evaluation often point to the underlying cause, and attention to general principles of environmental and pharmacologic management can minimize morbidity. 相似文献
998.
D Sherson H Nielsen J Frederiksen N Milman E Struve-Christensen B N Petersen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1992,100(5):408-414
Superoxide anion release (O2-) after stimulation with phorbol myristate acetate was measured in alveolar macrophages (AM) obtained by bronchoalveolar lavage and in blood monocytes from 47 patients with diffuse interstitial lung disease: idiopathic pulmonary fibrosis (N = 15), hypersensitivity pneumonitis (N = 7), pneumoconiosis (N = 6) and sarcoidosis (N = 19). Differential cell counts demonstrated a lymphocyte predominance in patients with hypersensitivity pneumonitis (HP) and sarcoidosis while the other groups had neutrophil predominance. No correlation between O2- activity in alveolar macrophages (AM) or blood monocytes (BM) compared to lung function (VC and diffusing capacity) could be demonstrated. Smoking pneumoconiotics had significantly decreased BM O2- release (1.25 +/- 0.25 (SEM) nmol/min/10(6) cells) and significantly increased AM/BM O2- ratios (2.04 +/- 0.26) compared to smokers with idiopathic pulmonary fibrosis (IPF) who had the following mean values: BM O2- release = 2.58 +/- 0.25 and AM/BM O2- ratio = 0.86 +/- 0.23. When matched for sex and smoking, a significantly increased AM/BM O2- ratio was seen among patients with HP (2.19 +/- 0.98) in comparison with patients who had sarcoidosis (0.40 +/- 0.18). Patients with either HP or pneumoconiosis had generally elevated AM O2- release and reduced BM O2- release. These results suggest that environmentally related interstitial lung disorders (HP and pneumoconiosis) may be associated with elevated AM O2- release relative to BM O2- release in comparison to non-environmentally related disorders (IPF or sarcoidosis). 相似文献
999.
Douglas B Nelson William R Jarvis William A Rutala Amy E Foxx-Orenstein Gerald Isenberg Georgia R Dash Carla J Alvarado Marilee Ball Joyce Griffin-Sobel Carol Petersen Kay A Ball Jerry Henderson Rachel L Stricof 《Infection control and hospital epidemiology》2003,24(7):532-537
Flexible gastrointestinal endoscopy is a valuable diagnostic and therapeutic tool for the care of patients with gastrointestinal and pancreaticobiliary disorders. Compliance with accepted guidelines for the reprocessing of gastrointestinal endoscopes between patients is critical to the safety and success of their use. When these guidelines are followed, pathogen transmission can be effectively prevented. Increased efforts and resources should be directed to improve compliance with these guidelines. Further research in the area of gastrointestinal endoscope reprocessing should be encouraged. The organizations that endorsed this guideline are committed to assisting the FDA and manufacturers in addressing critical infection control issues in gastrointestinal device reprocessing. 相似文献
1000.
Theodore J. Pysher Phillip R. Bach Amy Lowichik Mark D. Petersen Linda H. Shields 《Pediatric and developmental pathology》1999,2(5):446-453
Predefined multitest chemistry panels (PMCPs) have constituted a large proportion of laboratory tests and patient charges,
even in pediatric settings, despite the absence of documented clinical utility for PMCPs and the general availability of random
access analyzers that do not require predefined test combinations. We eliminated PMCPs in our tertiary children's hospital
but placed no other restrictions on ordering, and observed a 32.7% reduction in the number of automated chemistry tests ordered.
All 23 tests in the previous PMCPs showed a decline in utilization, >50% for 8 of the tests and 20–50% for 13 others, and
this change was sustained throughout an 8-month follow-up period. The total number of orders for one or more tests increased
by 8.2%, but the variety of combinations that were ordered increased by 280%. The most substantial changes included a decrease
in the number of orders for combinations of >15 tests, and increases in the number of orders for single tests and combinations
of 2 to 5 tests. Orders for combinations identical to all of the former PMCPs declined, with the exception of the 4-test electrolyte
panel. There was a marked decline in orders for a 7-test panel identical to the recently defined HCFA-AMA Basic Metabolic
Panel, and orders for combinations identical to the HCFA-AMA Liver Function and Extended Metabolic panels were vanishingly
rare and nonexistent, respectively. The calculated reduction in patient charges was much greater than actual cost savings,
but the reduction in total tests and increase in the variety of test combinations suggest that significant savings can be
realized if clinicians are encouraged to order only the tests or combinations they need without imposing procedural, financial,
and regulatory burdens.
Received June 30, 1998; accepted November 16, 1998. 相似文献