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91.
ML Kaptein C de Putter GL de Lange PA Blijdorp 《Canadian Metallurgical Quarterly》1998,56(12):1376-80; discussion 1380-1
PURPOSE: This retrospective study investigated the survival of dental implants placed in the maxilla after composite grafting of the sinus and an average of 55 months of loading. PATIENTS AND METHODS: Maxillary sinuses of 88 patients were grafted with autogenous cancellous bone combined with dense hydroxyapatite particles. After an average healing period of 3.4 months, hydroxyapatite-coated titanium endosseous implants were placed. A total of 388 implants were placed in grafted sinus floors, and 82 were placed in onlay grafted nonsinus position in the canine region. The implants were loaded with overdentures and fixed bridges 4 months (mean) after implantation, with a follow-up for a mean of 55 months. RESULTS: The cumulative implant survival was calculated according to the Kaplan-Meier method. Implant survival from the time of loading was 89% in full reconstructed cases and 90% in partially edentulous cases. The overall cumulative implant survival rate, including the loss in the surgical stage, was 82%. CONCLUSION: Implant loss in composite grafted maxillae after 70 months of follow-up was similar to loss in nongrafted maxillae. 相似文献
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93.
LM Kelley JP Walker GL Wing PA Raskauskas CL Schepens 《Canadian Metallurgical Quarterly》1997,28(7):565-569
BACKGROUND AND OBJECTIVE: The goal was to utilize ultrasound-guided cryotherapy as an immediate, low-risk, noninvasive, precise method of treating retinal tears obscured by vitreous hemorrhage. PATIENTS AND METHODS: Eleven patients with sudden onset of vitreous hemorrhage were referred for diagnosis and management. Ophthalmoscopy with scleral depression was unsuccessful at localizing peripheral retinal tears, and all of the patients were examined with ultrasound using the techniques of standardized echography. The cryoprobe was positioned for cryotherapy using both transverse and longitudinal B-scan approaches following the indentation of the globe as it appeared on the oscilloscope. RESULTS: On follow-up examination after the vitreous hemorrhage cleared, 10 of the 11 tears were examined by ophthalmoscopy and were thought to have been adequately treated. One patient had a retinal detachment after remaining stable for 3 months. Two patients were treated with laser to enhance the cryotherapy seal. One patient was observed by another physician and underwent vitrectomy due to vitreous hemorrhage that persisted 2 months following cryotherapy. After vitrectomy, the physician reported a successful cryotherapy reaction at the treated tear. One final patient in the series required vitrectomy and scleral buckle before the hemorrhage had cleared, and the treatment did not appear to be complete. CONCLUSION: Ultrasound-guided cryotherapy provides a noninvasive, inexpensive treatment alternative for retinal tears obscured by vitreous hemorrhage. 相似文献
94.
J Keane MK Balcewicz-Sablinska HG Remold GL Chupp BB Meek MJ Fenton H Kornfeld 《Canadian Metallurgical Quarterly》1997,65(1):298-304
The effect of Mycobacterium tuberculosis infection on the viability of healthy (control) human alveolar macrophages was evaluated by staining with ethidium homodimer and calcein to discriminate live from dead cells. Infection with M. tuberculosis H37Ra or H37Rv increased macrophage mortality at 6 days from the control level of 3.8% +/- 0.7% to 28.7% +/- 6.9% or 12.6% +/- 3.1%, respectively (P < 0.001 for comparisons of all conditions). A role for tumor necrosis factor alpha (TNF-alpha) in the M. tuberculosis-induced cytolysis of alveolar macrophages was demonstrated by increased cytotoxicity following the addition of exogenous TNF-alpha to the cultures and by enhancement of macrophage survival when M. tuberculosis-infected alveolar macrophages were treated with pentoxifylline or anti-TNF-alpha antibody. The cytolytic mechanism was determined to be apoptosis by the demonstration of a characteristic internucleosomal ladder of genomic DNA by agarose gel electrophoresis, by finding nuclear fragmentation and condensation by electron microscopy, and by in situ terminal transferase-mediated nick end labeling of fragmented DNA in alveolar macrophages infected with M. tuberculosis in vitro. The latter technique was employed to reveal extensive apoptosis within caseating granulomas from lung tissue samples from clinical tuberculosis cases. The induction of apoptosis in alveolar macrophages by M. tuberculosis may play a role in the macrophage-pathogen interaction of tuberculosis in vivo. 相似文献
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The development of cross-tolerance to an analgesic effect has been observed between a mu-receptor agonist, heroin, and a delta-receptor agonist, Met2-Pro5-enkephalinamide. Repeated treatments with heroin twice a day for 4 days resulted in a decreased nociceptive effect to enkephalin on day 5. The enkephalin dose-response line was shifted to the right, considered a sign of the development of cross-tolerance. Peripheral treatment with oxytocin blocked the development of heroin-enkephalin cross-tolerance. A similar effect was observed after intracerebroventricular administration of oxytocin, supporting our assumption that oxytocin blocks the development of heroin-enkephalin cross-tolerance via CNS mechanisms. 相似文献
97.
Membrane transporter proteins are encoded by numerous genes that can be classified into several superfamilies, on the basis of sequence identity and biological function. Prominent examples include facilitative transporters, the secondary active symporters and antiporters driven by ion gradients, and active ABC (ATP binding cassette) transporters involved in multiple-drug resistance and targeting of antigenic peptides to MHC Class I molecules. Transported substrates range from nutrients and ions to a broad variety of drugs, peptides and proteins. Deleterious mutations of transporter genes may lead to genetic diseases or loss of cell viability. Transporter structure, function and regulation, genetic factors, and pharmaceutical implications are summarized in this review. 相似文献
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99.
A Aliotta M Pompili GL Rapaccini I De Vitis S Caputo A Cedrone A Grattagliano G Gasbarrini 《Canadian Metallurgical Quarterly》1997,16(2):85-91; quiz 93-4
We studied, by means of Doppler ultrasonography, the blood flow in the superior mesenteric artery in 12 untreated patients with celiac disease (nontropical sprue) and in 15 healthy controls; peak systolic velocity, end diastolic velocity, mean velocity, flow volume, and resistive index were measured in the fasting state and at regular intervals after ingestion of 0.5 liter of water containing 50 g of saccharose. Under fasting conditions, celiac patients showed peak systolic velocity, end diastolic velocity, mean velocity, and flow volume values significantly higher than those of normal subjects, whereas resistive index was significantly lower. After saccharose ingestion these parameters showed greater variations in normal subjects than in celiac patients. Fasting end diastolic velocity turned out to be the best parameter to distinguish celiac patients from healthy subjects. Doppler ultrasonography of the superior mesenteric artery could discriminate between normal subjects and celiac patients with overt disease. However, these data need further confirmation given the limited sample that we studied; moreover, the capability of this technique in distinguishing nontropical sprue from other gastrointestinal diseases that cause increasing splanchnic flow remains to be ascertained. 相似文献
100.
BA Larsson A N?rstmo C Guthenberg GL Olsson P Danielsson L Hagenfeldt G Elander A Larsson 《Canadian Metallurgical Quarterly》1997,94(49):4625-4628
All newborns in Sweden are screened for phenylketonuria (PKU), among other things, blood usually being sampled by heel lancing. Because it is unnecessarily painful, however, this form of sampling in newborns has recently been questioned. There is reason to recommend sampling from a dorsal hand vein as the method of choice for PKU screening purposes. 相似文献