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31.
Schwarzer JU Fiedler K v Hertwig I Krüsmann G Würfel W Schleyer M Mühlen B Pickl U Löchner-Ernst D 《Urologia internationalis》2003,70(2):119-123
INTRODUCTION: Male infertility caused by azoospermia due to non-reconstructable obstruction or non-obstructive azoospermia can be treated by microsurgical epididymal aspiration (MESA) or testicular sperm extraction (TESE) followed by an intracytoplasmatic spermatozoa injection (ICSI). MATERIAL AND METHODS: From 9/93 to 6/01, we carried out 1,025 ICSI procedures with aspirated epididymal or testicular sperms in 684 cases. 163 ICSI cycles were performed with epididymal sperms and 862 ICSI cycles with testicular sperms or spermatids. The TESE was carried out by open biopsy, frequently in a multilocular technique. The aspirated spermatozoas were used after cryopreservation (frozen) or immediately after aspiration (fresh). RESULTS: 538 patients had obstructive azoospermia or ejaculation failure. In 487 cases the underlying cause of azoospermia was an impaired spermatogenesis, following maldescensus testis, chemotherapy, radiotherapy, or caused by Sertoli-cell-only syndrome, a genetic disorder or an unknown etiology. The transfer rates, pregnancy rates and birth rates per ICSI cycle showed no statistically significant differences between testicular and epididymal sperms in the cases of seminal obstruction (28% average birth rates in both cases). However, highly significant was the difference in birth rates with regard to the underlying cause of infertility. In contrast, in treating non-obstructive azoospermia we observed a birth rate of 19% per cycle. In all patient groups the birth rate with fresh spermatozoas did not differ from those with cryopreserved spermatozoa. 40% of patients after multilocular TESE showed clinical signs of testicular lesion. CONCLUSION: The underlying cause of azoospermia is the most important factor for the outcome of ICSI using epididymal and testicular sperms. In cases of non-obstructive azoospermia, the pregnancy rate is low compared with the results in cases of obstructive azoospermia. There is no difference between fresh and cryopreserved sperms. TESE with ICSI is the most efficient treatment of azoospermia caused by hypergonadotropic hypogonadism. The morbidity of the TESE procedure is highly relevant and must be considered if this technique is indicated. 相似文献
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The Internet, an increasingly pervasive part of our culture, has vastly increased the rate at which information is disseminated. Unfortunately, a substantial portion of medical information on the Internet is false or misleading. Realizing this, many patients would like their physicians to help guide their online searches for medical information, but most physicians do not feel comfortable enough with the Internet to provide this service. A recent poll by Cyberdialogue (2000) found that 70% of all patients would like their physicians to recommend a health care web site for their condition, but that only 4% of patients receive such a recommendation. In recommending medical web sites, physicians need to consider the quality of the web site, the quality of the content, and especially the ethics of the site. The most important ethical standard a web site must meet is the clear separation of its editorial comment from promotional material. Patients do not have enough knowledge to distinguish unbiased information from information designed to push a product or service. There are organizations such as the Health on the Net Foundation and the E-Health Code of Ethics that have established clear quality and ethical criteria, but very few resources exist for these organizations to use in policing the sites that claim to adhere to their criteria. The National Institutes of Health recently started a consumer web site (www.medlineplus.gov) that takes web sites that adhere to their stringent criteria and places them on their web site, thus ensuring proper compliance. Patient education from sources other than face-to-face contact with a physician should be seen as an adjunct to the medical practice of physicians, and not as competition. Information is a form of therapy, and should lead to better referrals, more realistic outcome expectations, better treatment compliance, and better outcomes. As long as patients are referred to information that is unbiased, well-written, and not proprietary, their decision making should be enhanced, bringing them into the decision-making loop. This allows the patient to be much more involved with his or her care. As the medical profession changes from a "gatekeeper" model to a patient choice model, patient education will take on a much greater role. 相似文献
33.
Assumed oxygen consumption frequently results in large errors in the determination of cardiac output
Fakler U Pauli C Hennig M Sebening W Hess J 《The Journal of thoracic and cardiovascular surgery》2005,130(2):272-276
OBJECTIVE: We sought to investigate the differences in assumed and measured oxygen consumption values for the determination of cardiac output by using the Fick principle in a pediatric population with congenital heart disease. METHODS: The patient population consisted of 143 patients with a mean age of 11.3 years (age range, 2 days to 23.8 years) undergoing cardiac catheterization during general anesthesia and with mechanical ventilation. Oxygen consumption was measured with a standard commercial analyzing system (Deltatrac II; Datex, Engstr?m, Helsinki, Finland). Assumed oxygen consumption values were calculated according to the formulas of Krovetz and Goldbloom and LaFarge and Miettinen. Comparisons between measurements and assumptions were performed by Bland-Altman plots. Two-sided paired t tests were used to assess a difference of the assumed and measured values. RESULTS: The range of measured oxygen consumption values was between 55.2 and 249 mL . min -1 . m -2 . The Krovetz-Goldbloom formula led to systematically larger values compared with the measured values (P = .0001; mean difference of -53.3 mL . min -1 . m -2 ; 95% confidence interval, -56.7 to -49.8 mL . min -1 . m -2 ). The use of the LaFarge-Miettinen formula tends to overestimate oxygen consumption (P = .0037; mean difference of -15.9 mL . min -1 . m -2 ; 95% confidence interval, -26.5 to -5.4 mL . min -1 . m -2 ). A similarly poor agreement was found when analyzing a subgroup of 25 patients with Fontan-type circulation. CONCLUSION: The use of assumed instead of measured oxygen consumption values introduces large errors in the determination of cardiac output. 相似文献
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Differential enhancement of collagen crosslink excretion in cases of osteosarcoma and chondrosarcoma
Açil Y Springer I Behrens P Ullrich KP Hedderich J Bruns J 《Journal of cancer research and clinical oncology》2003,129(10):583-588
Hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP) are markers of collagen absorption and LP is specific for collagen type I in bone. In the present study we evaluated the concentration of HP and LP in urine of patients with osteosarcoma (n=20; age range 16–49 years) and chondrosarcoma (n=15; age range 18–70 years). The values were compared with those obtained from 74 healthy controls (age range 16–83 years). The range and upper limit of normal values (HPmax and LPmax) were measured in our control group. High performance liquid chromatography (HPLC) was used to determine concentrations of HP and LP (nmol/mmol creatinine). The average urinary HP concentrations were significantly increased in patients with osteosarcoma (p=0.001) and chondrosarcoma (p<0.001), whereas HP remained within the normal range in approximately half of the patients. The average urinary LP concentrations were not increased in osteosarcoma and chondrosarcoma patients as compared with the control group. Further studies in a large group of patients are necessary to evaluate whether HP might be a valuable marker of prognosis, and if its urinary concentration can be correlated to tumour burden. 相似文献
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Extracorporeal CO2 removal as bridge to lung transplantation in life‐threatening hypercapnia 下载免费PDF全文
Peter Schellongowski Katharina Riss Thomas Staudinger Roman Ullrich Claus G. Krenn Christian Sitzwohl Andja Bojic Philipp Wohlfarth Wolfgang R. Sperr Werner Rabitsch Clemens Aigner Shahrokh Taghavi Peter Jaksch Walter Klepetko György Lang 《Transplant international》2015,28(3):297-304
In patients awaiting lung transplantation (LTX), adequate gas exchange may not be sufficiently achieved by mechanical ventilation alone if acute respiratory decompensation arises. We report on 20 patients with life‐threatening hypercapnia who received extracorporeal CO2 removal (ECCO2‐R) by means of the interventional lung assist (ILA®, Novalung) as bridge to LTX. The most common underlying diagnoses were bronchiolitis obliterans syndrome, cystic fibrosis, and idiopathic pulmonary fibrosis, respectively. The type of ILA was pumpless arteriovenous or pump‐driven venovenous (ILA activve®, Novalung) in 10 patients each. ILA bridging was initiated in 15 invasively ventilated and five noninvasively ventilated patients, of whom one had to be intubated prior to LTX. Hypercapnia and acidosis were effectively corrected in all patients within the first 12 h of ILA therapy: PaCO2 declined from 109 (70–146) to 57 (45–64) mmHg, P < 0.0001; pH increased from 7.20 (7.06–7.28) to 7.39 (7.35–7.49), P < 0.0001. Four patients were switched to extracorporeal membrane oxygenation due to progressive hypoxia or circulatory failure. Nineteen patients (95%) were successfully transplanted. Hospital and 1‐year survival was 75 and 72%, respectively. Bridging to LTX with ECCO2‐R delivered by arteriovenous pumpless or venovenous pump‐driven ILA is feasible and associated with high transplantation and survival rates. 相似文献
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