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31.
M Gagner A Pomp BT Heniford D Pharand A Lacroix 《Canadian Metallurgical Quarterly》1997,226(3):238-46; discussion 246-7
One hundred consecutive laparoscopic adrenal procedures for a variety of endocrine disorders were reviewed. There was no mortality, morbidity was 12%, and conversions was 3%. During follow-up, none had recurrence of hormonal excess. Laparoscopic adrenalectomy is the procedure of choice for adrenal removal except in carcinoma or masses > 15 cm. OBJECTIVE: The authors evaluate the effectiveness of laparoscopic adrenalectomy for a variety of endocrine disorders. SUMMARY BACKGROUND DATA: Since the first laparoscopic adrenalectomy was performed in 1992, this approach quickly has been adopted, and increasing numbers are being reported. However, the follow-up period has been too short to evaluate the completeness of these operations. METHODS: One hundred consecutive laparoscopic adrenal procedures from January 1992 until November 1996 were reviewed and followed for adequacy of resection. RESULTS: Eighty-eight patients underwent 97 adrenalectomies and biopsies. The mean age was 46 years (range, 17-84 years). Indications were pheochromocytomas (n = 25), aldosterone-producing adenomas (n = 21), nonfunctional adenomas (n = 20), cortisol-producing adenomas (n = 13), Cushing's disease (n = 8), and others (n = 13). Fifty-five patients had previous abdominal surgery. Mean operative time was 123 minutes (range, 80-360 minutes), and estimated blood loss was 70 mL (range, 20-1300 mL). There was no mortality, and morbidity was encountered in 12% of patients, including three patients in whom venous thrombosis developed with two sustaining pulmonary emboli. During pheochromocytoma removal, hypertension occurred in 56% of patients and hypotension in 52%. There were three conversions to open surgery. The average length of stay has decreased from 3 days (range, 2-19 days) in the first 3 years to 2.4 days (range, 1-6 days) over the past 16 months. During follow-up (range, 1-44 months), two patients had renovascular hypertension and none had recurrence of hormonal excess. CONCLUSION: Laparoscopic adrenalectomy is safe, effective, and decreases hospital stay and wound complications. Prior abdominal surgery is not a contraindication. Pheochromocytomas can be resected safely laparoscopically despite blood pressure variations. Venous thrombosis prophylaxis is mandatory. The laparoscopic approach is the procedure of choice for adrenalectomy except in the case of invasive carcinoma or masses > 15 cm. 相似文献
32.
MU Ferreira Q Liu M Kimura BT Ndawi K Tanabe F Kawamoto 《Canadian Metallurgical Quarterly》1998,84(6):1286-1289
Allelic diversity in the merozoite surface protein-1 (MSP-1) of Plasmodium falciparum, a major malaria vaccine candidate, was examined in clinical isolates from holoendemic northern Tanzania. The variable blocks 2, 4a, 4b, 6, and 10 of the MSP-1 gene were typed by allelic type-specific polymerase chain reaction. Twenty-four possible MSP-1 gene types were defined as unique combinations of allelic types detected in each variable block. Thirteen gene types were identified, and 187 P. falciparum populations were fully typed among 79 isolates. In contrast with recent findings in Vietnam, we were unable to detect nonrandom associations between allelic types in the typed variable blocks. Most patients (60%) harbored more than 1 genetically distinct parasite population (average: 2.37 populations per isolate) and, in 1 patient, 6 different versions of this single-copy gene were found. Statistical analysis suggests that parasites carrying different MSP-1 gene types are not independently distributed in the host population. The epidemiological consequences of these findings are discussed. 相似文献
33.
EA Dean-Nystrom BT Bosworth HW Moon AD O'Brien 《Canadian Metallurgical Quarterly》1998,66(9):4560-4563
Enterohemorrhagic Escherichia coli (EHEC) strains require intimin to induce attaching and effacing (A/E) lesions in newborn piglets. Infection of newborn calves with intimin-positive or intimin-negative EHEC O157:H7 demonstrated that intimin is needed for colonization, A/E lesions, and disease in cattle. These results suggest that experiments to determine if intimin-based vaccines reduce O157:H7 levels in cattle are warranted. 相似文献
34.
35.
Age-dependent MRI-detected lesions at early stages of transient global ischemia in rat brain 总被引:2,自引:0,他引:2
Canese R Lorenzini P Fortuna S Volpe MT Giannini M Podo F Michalek H 《Magma (New York, N.Y.)》2004,17(3-6):109-116
Although ischemic stroke has higher incidence and severity in aged than in young humans, the age factor is generally neglected in ischemia animal models. This study was aimed at comparing age-dependent effects at early stages of transient global cerebral ischemia (TGCI) in rats. TGCI was induced in two groups of rats (3–6 and 20–24 months old, respectively) by exposure to 15% oxygen and 15 min occlusion of the two common carotid arteries. Brains were analysed in vivo by MRI–apparent diffusion coefficient (ADC) and T2 maps–at 1–3 h post-TGCI and in vitro by histochemical examination of triphenyltetrazolium chloride (TTC)-stained slices. At 1–3 h post-TGCI, a higher incidence of lesions was found in aged than in young rats especially in the hippocampus and cortex (occipital plus parietal) but not in the thalamus. The lesioned regions showed lower ADC values in aged than in younger rats. The most substantial ADC decreases were associated with enhanced spin-spin relaxation and lower TTC staining. The different responses of the two age groups support the use of aged animals for investigations on different ischemia models. Our model of brain ischemia appears appropriate for further studies including drug effects. 相似文献
36.
G. Volpe R. Santoleri M. Ribera d'Alcalà F. D'Ortenzio 《Remote sensing of environment》2007,107(4):625-638
In this paper, uncertainties in the retrieval of satellite surface chlorophyll concentrations in the Mediterranean Sea have been evaluated using both regional and global ocean colour algorithms. The rationale for this effort was to define the most suitable ocean colour algorithm for the reprocessing of the entire SeaWiFS archive over the Mediterranean region where standard algorithms were demonstrated to be inappropriate. Using a large dataset of coincident in situ chlorophyll and optical measurements, covering most of the trophic regimes of the basin, we validated two existing regional algorithms [Bricaud, A., E. Bosc, and D. Antoine, 2002. Algal biomass and sea surface temperature in the Mediterranean Basin — Intercomparison of data from various satellite sensors, and implications for primary production estimates. Remote Sensing of Environment, 81(2-3), 163-178.; D'Ortenzio, F., S. Marullo, M. Ragni, M. R. d'Alcala and R. Santoleri, 2002. Validation of empirical SeaWiFS algorithms for chlorophyll-alpha retrieval in the Mediterranean Sea — A case study for oligotrophic seas. Remote Sensing of Environment, 82(1), 79-94.] and the global algorithm OC4v4 used for standard NASA SeaWiFS products. The results of our analysis confirmed that the OC4v4 performs worse than the two existing regional algorithms. Nonetheless, these two regional algorithms do show uncertainties dependent on chlorophyll values. Then, we introduced a better tuned algorithm, the MedOC4. Using an independent set of in situ chlorophyll data, we quantified the uncertainties in SeaWiFS chlorophyll estimates using the existing and new regional algorithms. The results confirmed that MedOC4 is the best algorithm matching the requirement of unbiased satellite chlorophyll estimates and improving the percentage of the satellite uncertainty, and that the NASA standard chlorophyll products are affected by an uncertainty of the order of 100%. Moreover, the analysis suggests that the poor quality of the SeaWiFS chlorophyll in the Mediterranean is not due to the atmospheric correction term but to peculiarities in the optical properties of the water column. Finally the observed discrepancy between the global and the regional bio-optical algorithms has been discussed analysing the differences between the two in situ datasets used for tuning the algorithms (SeaBASS versus ours). The main results are that methodological differences in the two datasets cannot play a major role and the inherent bio-optical properties of the basin can explain the observed discrepancy. In particular the oligotrophic water of the Mediterranean Sea is less blue (30%) and greener (15%) than the global ocean. 相似文献
37.
Multisensory integrated expressive environments is a framework for mixed reality applications in the performing arts such as interactive dance, music, or video installations. MIEEs address the expressive aspects of nonverbal human communication. We present the multilayer conceptual framework of MIEEs, algorithms for expressive content analysis and processing, and MIEEs-based art applications. 相似文献
38.
JF Watchko MJ Daood GC Sieck JJ LaBella BT Ameredes AP Koretsky B Wieringa 《Canadian Metallurgical Quarterly》1997,82(5):1416-1423
Creatine kinase (CK) is an enzyme central to cellular high-energy phosphate metabolism in muscle. To characterize the physiological role of CK in respiratory muscle during dynamic contractions, we compared the force-velocity relationships, power, and work output characteristics of the diaphragm (Dia) from mice with combined myofibrillar and sarcomeric mitochondrial CK deficiency (CK[-/-]) with CK-sufficient controls (Ctl). Maximum velocity of shortening was significantly lower in CK[-/-] Dia (14.1 +/- 0.9 Lo/s, where Lo is optimal fiber length) compared with Ctl Dia (17.5 +/- 1.1 Lo/s) (P < 0.01). Maximum power was obtained at 0.4-0.5 tetanic force in both groups; absolute maximum power (2,293 +/- 138 W/m2) and work (201 +/- 9 J/m2) were lower in CK[-/-] Dia compared with Ctl Dia (2,744 +/- 146 W/m2 and 284 +/- 26 J/m2, respectively) (P < 0.05). The ability of CK[-/-] Dia to sustain shortening during repetitive isotonic activation (75 Hz, 330-ms duration repeated each second at 0.4 tetanic force load) was markedly impaired, with CK[-/-] Dia power and work declining to zero by 37 +/- 4 s, compared with 61 +/- 5 s in Ctl Dia. We conclude that combined myofibrillar and sarcomeric mitochondrial CK deficiency profoundly impairs Dia power and work output, underscoring the functional importance of CK during dynamic contractions in skeletal muscle. 相似文献
39.
Pierre-Nicolas Volpe Pierre Muret Franck Omnes Jocelyn Achard François Silva Ovidiu Brinza Alix Gicquel 《Diamond and Related Materials》2009,18(10):1205-1210
Several 65 μm thick epitaxial diamond films prepared on (100) Ib substrates by high power pulsed microwave plasma assisted chemical vapour deposition (HP-MPCVD) are studied as a function of surface treatments by cathodoluminescence (CL) and photoluminescence (PL) spectroscopies. They are either asgrown, or polished, or etched by a microwave oxygen plasma, or after applying subsequently the two last processes. In CL spectra, bands due to defects occur at 2.3 eV, 3.07 eV, 3.7 eV and 4.7 eV, the last one being specific of polished surfaces, with nearly no contrast in the luminescence image. A fundamental result consists in demonstrating that the defects induced by polishing can be removed by oxygen plasma etching. Additionally, in order to assess how luminescence spectra originate from a peculiar depth or not, a bevelled sample is studied. PL spectra are acquired on the sample side while CL spectra are measured at several points on the bevel top side till to the Ib substrate. Comparison of the two sets of result show that the H3 signal originates from the Ib substrate even if it is present in the CL spectra of the film. An analysis of the change in the intensity of the TO free exciton line, defect bands and H3 signal, along decreasing photon energies, as a function of the thickness of the remaining HP-PMPCVD film, is performed with the help of a model taking the diffusion of the unrecombined excitonic pairs and the re-excited photoluminescence into account. CL images recorded at specific wavelengths, which do not show inverted contrast, are also assessed. From these data, the exciton diffusion length is evaluated to 11 μm in the major part of the epitaxial layer except for the first 20 μm close to the Ib substrate where it decreases down to 2 μm. This study sheds light on the interpretation of luminescence spectra excited by an electron beam in undoped diamond layers. Defects bands due to damages induced by polishing and etching processes are also documented. 相似文献
40.
C. Fernández-Lorenzo D. Araújo J. Martín R. Alcántara J. Navas M.P. Villar M.P. Alegre P.N. Volpe F. Omnès E. Bustarret 《Diamond and Related Materials》2010,19(7-9):904-907
A homoepitaxial boron-doped diamond single layer is investigated by means of Fourier transformed infrared spectroscopy (FTIR) and cathodoluminescence (CL). Both techniques are shown to be complementary. µ-FTIR mapping allows to determine the location of active boron while CL allows discernability between passivation and compensation. Hydrogen incorporation during chemical vapour deposition (CVD) growth is revealed to passivate boron acceptors. The obtained results highlight that plasma etching can induce a dissociation of B–H centres. 相似文献