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PubMed2005

Observation of biological samples using a scanning microwave microscope.

We present the application of a scanning microwave microscope technique to biological samples. Since dielectric properties of most biological samples originate mainly from the water they contain, we were able to obtain microscope images of biological samples by our scanning microwave microscope technique. As a model system, we have measured the electrical properties of water in the microwave region. The high dielectric constant and the large loss tangent of water were verified. Furthermore, we have measured the properties of water with differing amounts of sodium chloride concentration ranging from de-ionized water to the saturated solution. We have observed a significant change in the resonant frequency and Q value of the resonator as a function of sodium chloride concentration. The concentration dependence of the signals shows that our scanning microwave microscope technique can be useful for investigating the local electric behavior of biological samples with a simple model of ionic conduction.

Microscopy, Scanning Probe↗
PubMed2004

Microwave-superheated Vics Vapo Rub: an ocular public health danger.

PURPOSE: To report a case of a microwave-oven superheated petroleum-based liquid causing severe chemical and thermal ocular burns treated successfully with amniotic membrane transplantation. DESIGN: Observational case report. METHODS: Retrospective review of clinical case. RESULTS: A 77-year-old woman sustained a severe combined chemical and thermal burn from microwave-heated Vicks Vapo-Rub requiring amniotic membrane transplant, with subsequent development of phacomorphic glaucoma, requiring cataract extraction, and bullous keratopathy, requiring penetrating keratoplasty. CONCLUSIONS: As microwave oven use becomes more commonplace, the risk of superheating liquids becomes an increasingly significant ocular danger. Continued efforts to educate the public about safe microwave use is necessary. Additionally, amniotic membrane transplantation was found to be effective in managing a combined chemical and thermal ocular burn.

Aged↗
PubMed2003

Microwave radiation can alter protein conformation without bulk heating.

Exposure to microwave radiation enhances the aggregation of bovine serum albumin in vitro in a time- and temperature-dependent manner. Microwave radiation also promotes amyloid fibril formation by bovine insulin at 60 degrees C. These alterations in protein conformation are not accompanied by measurable temperature changes, consistent with estimates from field modelling of the specific absorbed radiation (15-20 mW kg(-1)). Limited denaturation of cellular proteins could explain our previous observation that modest heat-shock responses are induced by microwave exposure in Caenorhabditis elegans. We also show that heat-shock responses both to heat and microwaves are suppressed after RNA interference ablating heat-shock factor function.

Amyloid↗
PubMedDate not supplied

Randomized comparison of endoscopic microwave coagulation and endoscopic sclerosis in the treatment of bleeding peptic ulcers.

We conducted a prospective randomized trial to evaluate the effectiveness and safety of endoscopic microwave coagulation in comparison to endoscopic sclerosis in the treatment of peptic ulcer bleeding. Over 15 months 127 ulcer-bleeding patients with an actively bleeding vessel (N = 21), a non-bleeding vessel (N = 53), oozing hemorrhage (N = 25), or an adherent clot (N = 28) in the ulcer base were randomly assigned during endoscopy to receive treatment with endoscopic sclerosis or with microwave coagulation. There were no significant differences in effectiveness between endoscopic sclerosis and microwave coagulation in any of the assessed parameters: the percentage of patients with major recurrent hemorrhage (5 vs. 12), the percentage who needed emergency surgery (5 vs. 9), the mean (+/- SD) transfusion requirements (0.32 +/- 0.89 vs. 0.78 +/- 1.65), the mean number of hospital days (10.3 +/- 3.5 vs. 10.7 +/- 4.1), and the number of deaths due to bleeding (0 vs. 2) were similar in both groups. No case of perforation occurred in either group. The data suggest that microwave coagulation is as effective and safe as endoscopic sclerosis in the treatment of bleeding peptic ulcers.

Aged↗
PubMed2000

Analytical-scale microwave-assisted extraction.

Microwave-assisted extraction (MAE) is a process of using microwave energy to heat solvents in contact with a sample in order to partition analytes from the sample matrix into the solvent. The ability to rapidly heat the sample solvent mixture is inherent to MAE and the main advantage of this technique. By using closed vessels the extraction can be performed at elevated temperatures accelerating the mass transfer of target compounds from the sample matrix. A typical extraction procedure takes 15-30 min and uses small solvent volumes in the range of 10-30 ml. These volumes are about 10 times smaller than volumes used by conventional extraction techniques. In addition, sample throughput is increased as several samples can be extracted simultaneously. In most cases recoveries of analytes and reproducibility are improved compared to conventional techniques, as shown in several applications. This review gives a brief theoretical background of microwave heating and the basic principles of using microwave energy for extraction. It also attempts to summarize all studies performed on closed-vessel MAE until now. The influences of parameters such as solvent choice, solvent volume, temperature, time and matrix characteristics (including water content) are discussed.

Chemistry Techniques, Analytical↗
PubMed2003

Gas chromatographic-mass spectrometric study of the oil fractions produced by microwave-assisted pyrolysis of different sewage sludges.

The pyrolysis of sewage sludge was studied in a microwave oven using graphite as microwave absorber. The pyrolysis temperature ranged from 800 to 1000 degrees C depending on the type of sewage sludge. A conventional electrical furnace was also employed in order to compare the results obtained with both methods. The pyrolysis oils were trapped in a series of condensers and their characteristics such as elemental analysis and calorific value were determined and compared with those of the initial sludge. The oil composition was analyzed by GC-MS. The oils from the microwave oven had n-alkanes and 1-alkenes, aromatic compounds, ranging from benzene derivatives to polycyclic aromatic hydrocarbons (PAHs), nitrogenated compounds, long chain aliphatic carboxylic acids, ketones and esters and also monoterpenes and steroids. The oil from the electric oven was composed basically of PAHs such as naphthalene, acenapthylene, phenanthrene, fluoranthene, benzo[a]anthracene, benzofluoranthenes, benzopyrenes, indenepyrene, benzo[ghi]perylene, and anthanthrene. In contrast, these compounds were not produced in the case of microwave-assisted pyrolysis.

Gas Chromatography-Mass Spectrometry↗
PubMed1998

Tolerability of high energy transurethral microwave thermotherapy with topical urethral anesthesia: results of a prospective, randomized, single-blinded clinical trial.

PURPOSE: We determine the tolerability of high energy transurethral microwave thermotherapy with topical urethral anesthesia alone without supplementary systemic sedoanalgesia. MATERIALS AND METHODS: A total of 45 patients with symptomatic benign prostatic hyperplasia were randomized to high energy transurethral microwave thermotherapy using either topical urethral anesthesia alone (topical anesthesia group) or topical anesthesia with adjunctive intravenous sedoanalgesia (sedoanalgesia group). Pain was evaluated sequentially by means of a 0 to 10 visual analog scale score. Posttreatment followup included determinations of International Prostate Symptom Score, peak flow rate, post-void residual urine, and quality of life score at 6 and 12 weeks. RESULTS: Upon commencement of microwave treatment mean visual analog scale score was 1.3 (95% confidence interval [CI], 1.0 to 1.7) in the sedoanalgesia group and 1.4 (95% CI, 1.0 to 1.9) in the topical anesthesia group. During therapy visual analog scale score increased to a peak at 30 minutes of 2.0 (95% CI, 1.6 to 2.4) and 2.2 (95% CI, 1.7 to 2.6) in the sedoanalgesia and topical anesthesia groups, respectively. Thereafter, visual analog scale score continuously declined, falling to 0.1 (95% CI, 0.0 to 0.2) and 0.2 (95% CI, 0.0 to 0.3) in the 2 respective groups by 1 hour following conclusion of the treatment period. There was no statistically significant difference between the groups in the treatment profile of visual analog scale scores (p = 0.701). Significant posttreatment improvements were demonstrated in International Prostate Symptom Score, peak flow rate, post-void residual urine and quality of life scores but there were no significant differences between the groups in the magnitude of improvement in these outcome measures. CONCLUSIONS: High energy transurethral microwave thermotherapy is well tolerated by patients under topical anesthesia alone and, therefore, can be administered in the outpatient setting without potent medications that necessitate intensive patient monitoring, pose risks for side effects and add to treatment costs.

Aged↗
PubMed2001

Interstitial microwave thermal therapy for prostate cancer: method of treatment and results of a phase I/II trial.

PURPOSE: Interstitial microwave thermal therapy is experimental treatment for prostate cancer with the goal of curing disease, while causing fewer complications than standard treatment options. We present a method for delivering interstitial microwave thermal therapy using microwave radiating helical antennae inserted percutaneously under transrectal ultrasound guidance. We report the results of a trial of this method in 25 patients in whom primary external beam radiation therapy had previously failed. This patient group currently has limited curative options that are associated with a high complication rate. However, these recurrent tumors often remain localized to the prostate, and so they may be amenable to localized therapy. MATERIALS AND METHODS: Patients with proved prostatic adenocarcinoma were candidates for treatment when prostate specific antigen (PSA) was 15 ng./ml. or less and prostate volume was 50 cc. or less. Followup included PSA measurement, digital rectal examination, urinalysis, and documentation of adverse events at 4, 8, 12 and 24 weeks. Sextant biopsy was performed at week 24. The procedure involved the insertion of 5 antennae percutaneously through a modified brachytherapy template. The antenna arrangement was determined based on computer simulated predictions of temperature throughout the prostate. The prostate was dissected away from the rectum by an injection of sterile saline to provide a thermal barrier that protected the rectum from thermal damage. Temperatures were monitored using interstitial mapping thermistor probes that were also inserted through the template. A minimum peripheral target temperature of 55C but less than 70C was maintained for 15 to 20 minutes, while the urethra, rectum and hydrodissection space remained below 42C. The urethra and rectum were actively cooled in addition to hydrodissection. RESULTS: Peripheral target temperatures of 55C were achieved. The urethra and rectum remained at a safe temperature. The procedure, including setup and treatment, required approximately 2.5 hours of operating room time. At 24 weeks the PSA nadir was 0.5 ng./ml. or less in 52% of patients and 0.51 to 4 ng./ml. was achieved in an additional 40%. The negative biopsy rate at 24 weeks was 64%, assuming that 3 patients lost to followup would have had positive results. No major complications were observed and in most cases minor complications resolved within 3 months. CONCLUSIONS: Interstitial microwave thermal therapy for prostate cancer was developed to heat the prostate safely to a cytotoxic temperature. Experience with 25 patients in whom external beam radiation therapy for prostate cancer had failed indicates that the treatment is safe. Although our series indicates that this therapy may be effective, further studies and longer followup are required in larger patient groups to confirm the potential role of this therapy as an option for recurrent and primary prostate cancer.

Aged↗
PubMed2002

Microwave-induced pyrolysis of sewage sludge.

This paper describes a new method for pyrolyzing sewage sludge using a microwave furnace. It was found that if just the raw wet sludge is treated in the microwave, only drying of the sample takes place. However, if the sludge is mixed with a small amount of a suitable microwave absorber (such as the char produced in the pyrolysis itself) temperatures of up to 900 degrees C can be achieved, so that pyrolysis takes place rather than drying. Microwave treatments were also compared with those carried out in a conventional electric furnace, as well as the characteristics of their respective carbonaceous solid residues.

Electricity↗
PubMed2003

Study of factors affecting on the extraction efficiency of polycyclic aromatic hydrocarbons from soils using open-vessel focused microwave-assisted extraction.

As part of an evaluation of focused microwave-assisted extraction (FMAE) using an open-vessel system, the effects of matrix, moisture content, ageing, and solvent have been studied on the extraction efficiency of polycyclic aromatic hydrocarbons (PAHs) from spiked soils. PAHs were spiked onto three different uncontaminated air dried and originally wet soil matrices with 1- and 20-day ageing periods. Solvents used were hexane-acetone (1:1), cyclohexane-acetone (1:1) and dichloromethane. FMAE only required a small amount of solvent (20 ml) and short extraction time (10 min) in the open cell under 90 W of microwave power. The results revealed that the extraction efficiency strongly depends on the nature of soil matrix; moisture content may enhance the recoveries of PAHs for many cases; and, the influence of the type of solvent is not significant. A comparison between microwave extraction and 16-h Soxhlet extraction has been made on spiked soils. It evidenced that the microwave method under ambient pressure is a suitable alternative to Soxhlet method for the analysis of PAHs in soils. For the evaluation of the developed FMAE method, three reference materials were used. The PAHs recovered from three reference materials were in a good agreement with reference values.

Chemistry Techniques, Analytical↗
PubMed1995

Effects of trypsinization and microwave treatment on lectin labelling of microglial cells in paraffin-embedded sections from pre- and postnatal bovine brains.

The effects of microwave heat treatment on lectin histochemical staining of microglial cells with Griffonia simplicifolia B4 isolectin (GSA I-B4) and Ricinus communis agglutinin-I (RCA-I) in paraffin-embedded pre- and postnatal bovine brain tissue fixed in two different fixatives (Bouin's fluid and 4% neutral buffered formaldehyde) were examined, and the results compared with lectin labelling obtained in untreated and trypsinized serial sections. The results indicate that lectin labelling of bovine microglial cells depends on the kind of lectin applied, the fixative used for tissue preservation, the isotype of microglia to be labelled, and the pretreatment of tissue sections. In brain tissue fixed in Bouin's fluid, GSA I-B4 staining of both microglial isotypes, i.e., amoeboid and ramified microglial cells, was achieved without trypsinization. Staining of sections with RCA-I, however, yielded negative results both on untreated and on trypsinized sections. These findings suggest that species-specific differences in the density of binding sites accessible to GSA I-B4 and RCA-I, respectively, may exist. Pretreatment of sections by microwave irradiation had different effects depending on the lectin and fixative used and on the microglial isotype to be stained. Microwave heat treatment of sections prior to incubation with RCA-I enabled the labelling of amoeboid and ramified microglial cells. The latter cell type, however, was exclusively stained in brain tissue fixed in Bouin's fluid. With GSA I-B4, exclusively the labelling of ramified microglial cells in sections fixed in Bouin's fluid was improved. It is assumed that by microwave pretreatment of sections from bovine brain the access of both lectins to their receptors, i.e., D-galactose residues on microglial cells, may be facilitated.

Animals↗
PubMed1998

Contrasting heating patterns and efficiency of the Prostatron and Targis microwave antennae for thermal treatment of benign prostatic hyperplasia.

OBJECTIVES: To determine the design and performance characteristics of two microwave antennae for use in thermal treatment of benign prostatic hyperplasia. METHODS: Prostatron and Targis antennae were subjected to detailed physical examination and measurement. The heating patterns generated by these two types of antennae were characterized in detail using tissue-equivalent phantoms. Measurements of return loss as a function of frequency were conducted to evaluate the capacity of the antennae for impedance matching. Percent reflected power was calculated from the return loss results to provide a relative measure of potential for efficient delivery of thermal energy. RESULTS: The Prostatron antenna was found to be a monopole design consisting of a coaxial cable with a 3.3-cm length of inner conductor exposed at the tip. The Targis antenna was observed to be a dipole design with a 2.8-cm helical coil attached through a ground connection and a tap point to a coaxial cable. The heating pattern of the Targis antenna was symmetric; that of the Prostatron was asymmetric with substantial back heating along the catheter axis in the direction of the microwave power source. The mean extension of the 30 degrees C isotherm in the direction of the power source with the Prostatron antenna (71.5 mm; 95% confidence interval [CI], 63.4 to 79.6 mm) was 55% greater (P < 0.0005) than that with the Targis antenna (46.0 mm; 95% CI, 38.2 to 53.8 mm). Return loss with the Targis antenna declined sharply to a relative minimum value of -32.9 dB (95% CI, -73.8 to 8.0 dB) at 915 MHz, providing evidence of this antenna's capacity for impedance matching; little change was observed with the Prostatron in return loss over a frequency range 100 MHz above and below this antenna's standard operating frequency of 1296 MHz. The mean reflected power of the Targis antenna (0.4%; 95% CI, 0.0% to 1.4%) was lower by more than 20-fold (P = 0.036) than that of the Prostatron antenna (11.0%; 95% CI, 3.4% to 18.7%); thus, the potential for efficient operation was greater with the Targis than the Prostatron antenna. CONCLUSIONS: The Targis microwave antenna was found to provide a more targeted heating pattern and have a capacity for more efficient thermal energy delivery than the Prostatron antenna. These differences observed in vitro could potentially translate into clinical advantages in vivo, such as improved tolerability of microwave treatment, reduced risk of complications, greater thermoablative efficacy, and scalability.

Diathermy↗
PubMed1999

Does transurethral microwave thermotherapy have a different effect on prostate cancer than on benign or hyperplastic tissue?

OBJECTIVES: Transurethral microwave thermotherapy is useful for the treatment of benign prostatic hyperplasia, but its effect on cancer is not documented. We analyzed the pathologic changes occurring after microwave thermotherapy in whole mount radical prostatectomy specimens from patients with cancer. METHODS: Nine patients scheduled for radical prostatectomy for clinically localized prostate cancer were treated with transurethral microwave thermotherapy (Urologix Targis System). Patients ranged in age from 64 to 72 years (mean 68). Seven patients underwent prostatectomy 4 to 90 hours after thermotherapy, and 2 other patients underwent prostatectomy 12 months after thermotherapy. Whole mount totally embedded prostates were mapped for necrosis and cancer, and the volume of each was measured by the grid method. RESULTS: Pathologic stages were T2a (n = 4), T2b (n = 4), and T3b (n = 1). The prostates from patients who underwent radical prostatectomy within 4 to 90 hours of thermotherapy had a mean prostate weight of 47.4 g (range 19.5 to 70.3). Each consistently showed hemorrhagic necrosis and tissue devitalization without significant inflammation. Necrosis involved contiguous areas of benign epithelium, stroma, and cancer without skip areas. The mean volume of necrosis was 8.8 cc (range 1.4 to 17.8), and the mean percentage of the prostate involved by necrosis was 22% (range 3% to 39%). The necrosis was symmetric around the urethra in 6 of 7 cases. Urethral dilation was observed in 3 patients, and the mean maximum radial distance of necrotic tissue was 1.4 cm (range 0.6 to 1.8). Necrotic change was noted in 80% to 100% of the volume of cancer in 4 cases, 40% to 60% in 2 cases, and 5% in 1 case. The prostates from the 2 patients who underwent radical prostatectomy 12 months after thermotherapy had a mean weight of 88 g (55 and 121 g, respectively). Each showed periurethral fibrosis, nonspecific chronic inflammation, and squamous metaplasia of the urothelium. The mean volume of necrosis remaining was 0.2 cc. The mean percentage of the prostate involved by necrosis 1 year after thermotherapy was less than 1%. There was some reabsorption of dead tissue. The mean maximum radial distance of the necrotic tissue was 0.4 cm (0.2 and 0.7 cm, respectively). The prostatic urethra had viable and partially denuded urothelium in all cases. CONCLUSIONS: Microwave thermotherapy is clinically useful for ablation of benign prostate and cancer contiguous to the urethra, resulting in hemorrhagic necrosis with minimal damage to the urethra. There was no apparent differential morphologic sensitivity of benign prostatic tissue, hyperplastic tissue, or cancer to thermotherapy.

Aged↗
PubMed2000

Pretreatment prostate-specific antigen as an outcome predictor of targeted transurethral microwave thermotherapy.

OBJECTIVES: To evaluate pretreatment serum prostate-specific antigen (PSA) as an outcome predictor of targeted microwave thermotherapy. METHODS: Seventy-one patients with lower urinary tract symptoms of benign prostatic hyperplasia underwent targeted transurethral microwave thermotherapy using the Targis system. Outcomes 12 months after treatment were evaluated by the International Prostate Symptom Score (IPSS), peak urinary flow rate (Qmax), and quality-of-life (QOL) score. The ability of PSA to predict outcomes was evaluated by linear and logistic regression and receiver operating characteristic curve analysis. RESULTS: Higher pretreatment PSA levels were significantly predictive of an absolute IPSS change of -7.5 or less for patients with moderate baseline symptoms or - 15 or less for those with severe baseline symptoms; an absolute Qmax change of 5 mL/s or greater; an absolute QOL score change of -3 or less; an IPSS at 12 months of 7 or less; a Qmax at 12 months of greater than 12 mL/s; and a QOL score at 12 months of 1 or less. Nevertheless, even without taking pretreatment PSA into account, most patients benefitted substantially from targeted microwave thermotherapy. Thus, 74%, 71%, and 79% of all eligible patients improved 50% or more in IPSS, Qmax, and QOL score, respectively, at 12 months compared with baseline. No significant association between PSA and either prostate or transition zone volume could be demonstrated. CONCLUSIONS: Most patients benefit substantially from targeted microwave thermotherapy. However, higher PSA levels are significantly predictive of more favorable outcomes. This association may reflect patient-to-patient differences in the relative abundance of PSA-producing epithelial cells in the transition zone of the prostate.

Aged↗
PubMed1996

Temperature-correlated histopathologic changes following microwave thermoablation of obstructive tissue in patients with benign prostatic hyperplasia.

OBJECTIVES: To determine the intraprostatic pathologic changes following accurately measured doses of transurethral microwave thermal energy in patients with benign prostatic hyperplasia. METHODS: Eight patients scheduled for prostate surgery were treated for approximately 1 hour without anesthesia using a newly designed microwave treatment catheter that allows a close impedance match to prostate tissue and concentrates thermal energy preferentially in the anterior and lateral prostate gland. Interstitial, urethral, and rectal temperatures were continuously measured using a novel stereotactic thermal mapping technique. Serial sections of prostate tissue harvested during subsequent surgery were evaluated pathologically with prostate mapping. RESULTS: Microwave treatment resulted in marked and continuous intraprostate temperature elevation, while urethral and rectal temperatures remained low. Peak intraprostate temperatures in individual patients reached as high as 80 degrees C. Mean temperature reached a maximum of 54 degrees C at a radial distance of approximately 0.5 cm from the urethra and remained 45 degrees C or higher up to a distance of 1.6 cm. The predominant pathologic findings were uniform hemorrhagic necrosis and tissue devitalization without significant inflammation. The mean distance from the urethra to the viable-necrotic tissue border was 1.6 +/- 0.2 cm (range, 0.5 to 2.5). At this border, no more than 1 mm in thickness, temperature averaged 45.7 +/- 0.6 degrees C, and there was a suggestion that pure stromal nodules were more resistant to thermal injury. CONCLUSIONS: Microwave treatment can destroy obstructive prostate tissue while maintaining innocuous urethral and rectal temperatures. Temperatures of 45 degrees C or higher for approximately 1 hour cause uniform thermoablation of prostate tissue.

Body Temperature↗
PubMed1992

Microwave-stimulated chemical fixation of whole eyes.

BACKGROUND: Microwave-stimulated chemical fixation has been used successfully to rapidly prepare nonocular tissue for processing and paraffin embedding. METHOD: This same technique was adapted to fix whole eyes using a common domestic microwave oven. Histologic sections were compared with sections from globes that were fixed in a traditional manner. RESULTS: Histologic sections and histochemical and immunohistochemical staining of eyes treated with microwave-stimulated chemical fixation in 10% neutral-buffered formalin were comparable in quality to eyes fixed in 10% neutral-buffered formalin at room temperature for 48 hours. CONCLUSION: Because microwave irradiation accelerates the most time-consuming part of preparing whole eyes for light microscopy, the technique enhances laboratory efficiency. The technique is particularly well suited for ensuring adequate fixation of globes when histologic diagnosis is needed in less than 48 hours.

Animals↗
PubMed2003

Does microwaving enhance the Golgi methods? A quantitative analysis of disparate staining patterns in the cerebral cortex.

As a family of techniques, the Golgi methods have long been used for studying the morphology and structure of the central nervous system. Due to their capricious nature, many modifications have been employed to improve the reliability and quality of the technique, including the recent addition of microwave energy. In the present study, we evaluated the effectiveness of adding microwave energy to two Golgi methods: the Golgi-Cox method and the rapid Golgi method. These methods were selected for their widespread use in animal research and human postmortem studies. Control tissue was compared to tissue exposed to microwave energy for varying lengths of time during the chromating step of both methods. As assessed by stereological cell counts and qualitative observation, the addition of microwave energy improved the quality of the impregnations and the number of labeled profiles in both methods up to a specific limit of exposure. Surprisingly, increases in the number of profiles were often the result of increased non-neuronal staining at the expense of neuronal staining. This result appears to be due to the fact that different classes of labeled profiles displayed distinct staining time courses.

Animals↗
PubMed1997

Microwave fixation of rabies specimens for fluorescent antibody testing.

An adaptation of the conventional procedure for fixation of brain impressions prior to rabies testing was developed using a microwave oven to fix slides in less than 1 min. A total of 2394 routine specimens were examined to evaluate the efficacy of microwave fixation of brain impressions as an aid to shortening the turnaround time for reporting. Slides were fixed for 55-60 s in a standard household microwave oven at 50%, power using phosphate buffered saline supplemented with 3% Tween 20 as a fixative medium. They were then stained using the standard rabies immunofluorescent staining procedure with minor modifications. This process potentially could allow results to be reported to submitters within 1.5 h after specimens arrive in the laboratory. Microwave fixation was in complete agreement with conventional acetone fixation for detection of positive rabies specimens.

Animals↗