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21.
It is well recognized that the ability to cryopreserve unfertilizedhuman oocytes would make a significant contribution to infertilitytreatment. However, despite considerable interest, very fewsuccessful pregnancies have arisen from cryopreserved oocytesafter thawing, insemination and transfer of the subsequent embryo.The reasons for this lack of progress may well result from adearth of information on how the various biophysical changesduring a cryopreservation regimen affect human oocyte function.Recently, fundamental studies on the effects of cooling, membranepermeability, cryoprotectant addition and ice formation havebeen performed on human oocytes by a number of groups, and theseform the basis of the current review. It is likely that successfulhuman oocyte cryopreservation will only follow once these factorsare fully understood, but the existing base of knowledge shouldprovide a platform for further improvements in the techniquescurrently employed. 相似文献
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KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
25.
Involvement of nitric oxide in angiogenic activities of vascular endothelial growth factor isoforms 总被引:1,自引:0,他引:1
Józkowicz A Dulak J Nigisch A Funovics P Weigel G Polterauer P Huk I Malinski T 《Growth factors (Chur, Switzerland)》2004,22(1):19-28
We compared effects of vascular endothelial growth factor-121 (VEGF121) and vascular endothelial growth factor-165 (VEGF165) on generation of NO in HUVEC and the involvement of NO in VEGF121- and VEGF165-induced angiogenesis. VEGF stimulated synthesis of NO within seconds, reaching peak concentrations of 450 +/- 25 and 180 +/- 15 nmol/l for VEGF121, and VEGF165, respectively. The VEGF121 increased NO production for about 40 s while VEGF165-stimulated NO release lasted only for about 20 s. Accordingly, cGMP elevation was stronger in VEGF121- than in VEGF165-treated cells. The VEGF121 was a very weak mitogen but strong chemoattractant for HUVEC, whereas VEGF165 potently induced both cell proliferation and migration. NO appeared to be involved in the endothelial migration and morphogenesis but not in the proliferation. NO was also a permissive molecule for VEGF121- but not for VEGF165-induced capillary sprouting in spheroid culture. In conclusion, VEGF121 is a stronger stimulator of endothelial nitric oxide synthase (eNOS) activity, and angiogenic potential of VEGF121 is more reliant on NO contribution. 相似文献
26.
E. K. Reddy L. Krishnan S. Giri R. G. Evans W. K. Mebust J. W. Weigel 《Journal of the National Medical Association》1993,85(2):109-112
From 1975 to 1982, 205 patients with local prostate cancer were treated at the radiation oncology department, the University of Kansas Medical Center, Kansas City, Kansas. Patients'' median age was 73 years. All of the patients were staged according to American Urologic staging criteria. Twenty-eight patients had stage A2 cancer, 91 patients had stage B cancer, and 86 patients had stage C cancer. All patients were treated using megavoltage radiation (dosage range: 6000 cGy to 7100 cGy). The follow-up period ranged from a minimum of 8 years to a maximum of 15 years (median: 9.4 years). The clinical local control was 96% for stage A2, 94% for stage B, and 90% for stage C disease. The overall and disease-free survival rates were 71% and 60%, respectively. Fourteen patients developed moderate complications with one patient (0.5%) requiring surgical intervention. The local control and survival rates reported in this study are comparable with surgical results, suggesting that external beam irradiation in prostate cancer is safe and effective. 相似文献
27.
Ziegan Joseph B. Weigel Bernd Salomon Franz-V. 《International journal of legal medicine》1985,94(4):289-299
Zusammenfassung Die Myophosphorylasereaktion (MPR) zeigt bei der malignen Hyperthermie (MH) charakteristische Veränderungen, die in Minutenschnelle entstehen: 1.) eine allgemein stark abgeschwächte Reaktion, 2.) zahlreiche negativ reagierende Fasern, 3.) häufig fleck- und/oder streifenförmig abgeschwächt oder negativ reagierende und streifenförmig verstärkt reagierende Faserabschnitte mit relativ engen Sarkomerenabständen (Zeichen der Hyperkontraktion). Diese morphologischen Befunde mit den kennzeichnenden Streifenfasern sind offenbar für das MH-Syndrom spezifisch! Wichtig ist, daß die derart veränderten Muskelfasern in der Regel bei den anderen Färbungen und Reaktionen unauffällig sind.Wir sahen diese pathologische MPR bei 5 verstorbenen Patienten, einmal unabhängig von einer Anästhesie nach einem Marsch, und bei 19 Schweinen, davon 18mal nach dem Halothantest und einmal bei einem Versuchstier mit gesicherter MH. Sie fehlte bei Schweinen mit negativer Halothanreaktivität und vor dem Halothantest und bei vielen, sehr verschiedenen gesunden und kranken Kontroll- und Vergleichsfällen aus dem bioptischen und autoptischen Untersuchungsgut. Die MPR erlaubt den sicheren Nachweis einer inszenierten oder abgelaufenen MH und damit eine Aufklärung rätselhafter oder scheinbar klarer Todesfälle während oder nach der Narkose oder allgemein nach Streß (human stress syndrome), von denen sicher viele der klinischen Aufmerksamkeit und den üblichen morphologischen Untersuchungsmethoden entgehen. Sie ist nicht geeignet, potentielle Opfer zu erkennen.Mit Unterstützung des Ministeriums f. Gesundheitswesen (HFR Schwangerschaft und frühkindliche Entwicklung, FR Genetische Defekte). Auszugsweise vorgetragen auf dem IV. Internationalen Myologie-Kolloquium in Jena 1984 相似文献
28.
D Wertlieb C Weigel T Springer M Feldstein 《The American journal of orthopsychiatry》1987,57(2):234-245
Data on 158 children, six and nine years old, are analyzed for the relationship between stress and behavior. Undesirable life events and intense "hassles" were particularly correlated with behavioral symptoms. Statistically, temperament appears to moderate this influence but, lacking appreciable variance of symptoms in the models including these interaction effects, the more parsimonious main-effects concept may be more useful. 相似文献
29.
Subjective tinnitus is a common problem with many etiologies. Objective tinnitus, in which the sound is perceived by both the patient and the examiner, is less common. Objective tinnitus of the vascular type, in which a pulse synchronous bruit is heard by an independent observer, is frequently related to an underlying arterial or arteriovenous malformation, most commonly a dural arteriovenous fistula (DAVF) involving the transverse and sigmoid sinuses. The remaining cases are usually termed "essential" vascular tinnitus, and are presumed to have a venous etiology. In these cases, the audible noise is generally assumed to be produced within the sino-jugular connection, or within an enlarged jugular bulb. We present four documented cases of objective pulse synchronous tinnitus due to focal narrowing (acquired and developmental) of the mid-portion of the transverse dural sinus. In all cases, a bruit was audible directly over a focal constriction in the sinus, demonstrated by cerebral angiography or direct catheter venography. In one case, selective venography revealed a distensible sinus narrowing, associated with a jet of contrast marking fast flow within a developmental sinus segmentation. In another case, a loud pulse synchronous bruit was heard directly over a focal transverse sinus stenosis, which was detected by angiography at the site of a vascular surgical clip. In this case, magnetic resonance (MR) falsely predicted sinus occlusion. In two other cases, an audible bruit was also heard directly overlying a narrowed transverse sinus, seen in the venous phase of angiography. Transverse sinus stenosis is an unappreciated cause of objective pulsatile tinnitus, and we believe that this mechanism may underlie many cases of "essential" or venous etiology tinnitus not otherwise anatomically explained. Non-invasive testing, computed tomography (CT) and MR and non-directed angiography may overlook it. Conventional catheter arteriography or venography should be performed in such cases, with attention to the dural sinuses, if other tests fail to define the anatomic basis of the audible bruit. 相似文献
30.
Surgical management of symptomatic spinal metastases. Postoperative outcome and quality of life 总被引:8,自引:0,他引:8
STUDY DESIGN: Eighty-six surgical interventions in 76 consecutive patients with symptomatic spinal metastases were reviewed retrospectively. OBJECTIVES: To evaluate the postoperative outcome and quality of life of patients surgically treated for symptomatic spinal metastases. SUMMARY OF BACKGROUND DATA: The standard surgical treatment for patients with symptomatic spinal metastases is anterior spinal cord decompression with stabilization. However, because therapy is only palliative, satisfactory quality of life and high patient acceptance are essential. METHODS: The medical records of all patients were reviewed retrospectively. Furthermore, all surviving patients or the next of kin of deceased patients were interviewed by telephone, and the family doctors or the care-providing physicians of external institutions were contacted. RESULTS: First-choice surgical treatment was anterior spinal cord decompression with stabilization. Postoperative mean survival was 13.1 months, and mean time at home after spinal surgery was 11.1 months. Neurologic improvement with regard to Frankel classification was observed in 58% of the patients, and 93% were able to walk postoperatively. Pain relief was noted in 89%. Overall, 67% of the patients achieved moderate or good general health as shown by the Karnofsky Index, and 80% were satisfied or very satisfied with the surgical intervention. Moreover, 19% of the surgical interventions were associated with complications, local tumor recurrence developed in 22% of the patients, and paraplegia ultimately developed in 18% of patients. CONCLUSIONS: Surgical management of symptomatic spinal metastases, in particular anterior decompression, is of benefit in most metastatic lesions in terms of satisfactory postoperative outcome and quality of life. However, in patients with melanoma or lung carcinoma, the authors advocate spinal surgery only in very exceptional cases. 相似文献