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PubMed1998

Facile Reduction of Tungsten Halides with Nonconventional, Mild Reductants. 2. Four Convenient, High-Yield Solid-State Syntheses of the Hexatungsten Dodecachloride Cluster W(6)Cl(12) and Cluster Acid (H(3)O)(2)[W(6)(&mgr;(3)-Cl)(8)Cl(6)](OH(2))(x)(), Including New Cation-Assisted Ternary Routes.

Tungsten hexachloride was reduced by Hg or Bi at moderately low temperatures ( approximately 350 degrees C) to afford good yields (Hg, 73%; Bi, 85%) of W(6)Cl(12) after conversion of the reduction product to the chloro acid (H(3)O)(2)[W(6)(&mgr;(3)-Cl)(8)Cl(6)](OH(2))(x)(), recrystallization, and thermolysis in vacuo. Antimony was a less effective reductant because of the lower yield of chloro acid (31%) and the substantial quantities of insoluble byproducts found after HCl workup. The yield of (H(3)O)(2)[W(6)(&mgr;(3)-Cl)(8)Cl(6)](OH(2))(x)() from WCl(6) reduction by Sb improved dramatically to 79% with added KCl, while LiCl reduced the yield to only traces. In Bi reduction of WCl(6), the yield of (H(3)O)(2)[W(6)(&mgr;(3)-Cl)(8)Cl(6)](OH(2))(x)() decreased from 86 to 49% upon addition of NaCl, whereas added KCl had no effect on the yield. The Hg-, Bi-, Sb/KCl-, and Bi/KCl-based routes offer substantial experimental advantages over published methods for preparation of (H(3)O)(2)[W(6)(&mgr;(3)-Cl)(8)Cl(6)](OH(2))(x)() and W(6)Cl(12).

Journal Article↗
PubMed2001

Coriander spice oil: effects of fruit crushing and distillation time on yield and composition.

Crushing intensity and distillation time were evaluated for their effects on the oil yield and composition of steam-distilled essential oil from fruits of Coriandrum sativum var. microcarpum L. A comparison of oils produced by laboratory- and pilot-scale stills showed that the two still types gave comparable yields and oil composition. The laboratory still was then used to compare oil yields and compositions from fruits crushed at three different intensities, at intervals during a distillation period of 60 min. Both crushing intensity and distillation time had significant (P< 0.05) effects on the yield and composition of the oil. The maximum oil yield was less from the light-crushed fruits, but the rate of oil recovery was significantly P < 0.05) higher. From the light-crushed fruits, 95% of the maximum yield was extracted in 22.5 min compared with 32 and 39 min for the standard and heavy-crushed fruits, respectively. The effect of crushing intensity on oil composition was most pronounced on the low-boiling-point a-pinene and on the higher-boiling-point geranyl acetate. Crushing had little effect on linalool content, but distillation time could be manipulated to alter the linalool content of the oil.

Acyclic Monoterpenes↗
PubMed2005

Hydrated electron yields in the heavy ion radiolysis of water.

Experimental measurements coupled with Monte Carlo track simulations have been used to examine the yields of hydrated electrons in the radiolysis of water with protons, helium ions, and carbon ions. Glycylglycine, in concentrations ranging from 10(-4) to 1 M, was employed as a scavenger and the production of the ammonium cation used as a probe of hydrated electron yields from about 2 ns to 20 mus. Monte Carlo track simulations employing diffusion-kinetic calculations of product yields are found to reproduce experimental observations satisfactorily. Model details are used to elucidate the heavy ion track physics and chemistry. Comparison of the heavy ion results with those found in gamma radiolysis shows intratrack reactions are significant on the nanosecond to microsecond time scale as the ion track relaxes, and that a constant (escape) yield is never attained on this time scale. Numerical interpolation techniques are used to obtain both track average and track segment yields for use in practical applications or comparison with other models. The model results give the first hints that initial ( approximately 5 ps) hydrated electron yields, and possibly other water decomposition products, are dependent on the type and energy of the incident radiation.

Letter↗
PubMed2006

Kinetic and product yield study of the heterogeneous gas-surface reaction of anthracene and ozone.

Little quantitative information exists regarding the products of the heterogeneous reaction of polycyclic aromatic hydrocarbons (PAHs) and ozone. We have, therefore, performed the first quantitative study investigating the kinetics and products of the heterogeneous gas-surface reaction of anthracene and ozone as a function of ozone concentration and relative humidity (RH). The reaction exhibited pseudo-first-order kinetics for anthracene loss under dry conditions (RH < 1%) and the pseudo-first-order rate coefficients displayed a Langmuir-Hinshelwood dependence on the gas-phase ozone concentration, which yielded the following fitting parameters: the equilibrium constant for ozone adsorption, K(O3) = (2.8 +/- 0.9) x 10(-15) cm3 and the maximum pseudo-first-order rate coefficient, k(I)max = (6.4 +/- 1.8) x 10(-3) s(-1). The kinetics were unchanged when experiments were performed at approximately 50% and 60% RH. In the product study, a nonlinear dependence, similar to a Langmuir adsorption plot, of the anthraquinone product yield as a function of ozone concentration was observed and resulted in the following fitting parameters: K(O3) = (3.4 +/- 1.5) x 10(-15) cm3 and the maximum anthraquinone yield, ANQmax % = 30 +/- 18%. Experiments performed under higher relative humidity conditions ( approximately 50% and 60% RH) revealed that the anthraquinone yield was unaffected by the presence of gas-phase water. It is noteworthy that both the anthracene loss kinetics and the anthraquinone yields have a similar dependence on the degree of ozone partitioning to the surface. This can be understood in terms of a mechanism whereby the rate-determining steps for anthracene loss and anthraquinone formation are both driven by the amounts of ozone adsorbed on the surface. Our results suggest that at atmospherically relevant ozone concentrations (100 ppb) the anthraquinone yield from the ozonolysis of anthracene under dry and high relative humidity conditions would be less than 1%.

Air↗
PubMed2004

Photophysics on surfaces: determination of absolute fluorescence quantum yields from reflectance spectra.

A method for the calculation of absolute fluorescence quantum yields for dyes attached to solid particles based on reflectance measurements is reported. The same procedure allows calculation of true reflectance spectra (free of fluorescence) for highly fluorescent materials as well. Samples ofcresyl violet were immobilized by adsorption on microgranular cellulose in the concentration range 4.5 x 10(-9) to 3.8 x 10(-6) mol g(-1). Diffuse and total reflectance spectra were recorded with and without insertion of an optical absorption filter between the output of the integrating sphere of a reflectance spectrometer and the photodetector in order to block fluorescence partially. From these data, the relative emission spectrum of the dye, the filter transmission spectrum, and the detector sensitivity, true reflectances and absolute fluorescence quantum yields were recovered. Observed fluorescence quantum yields, affected by dye aggregation and inner filter effects, were concentration and wavelength dependent, ranging approximately between 0.1 and 0.6. The analysis of remission function spectra showed that dye aggregation is negligible up to a concentration of 1.41 x 10(-7) mol g(-1). Fluorescence data were corrected for reemission and reabsorption using a suitable model [Lagorio, M. G.; Dicelio, L. E.; Litter, M. I.; San Roman, E. J. Chem. Soc., Faraday Trans. 1998, 94, 419]. Application of this model to samples showing no aggregation yielded a wavelength-independent true fluorescence quantum yield of 0.60 +/- 0.05, similar to values found in solution. The usage of cresyl violet as a reference for the evaluation of fluorescence quantum yields for weakly fluorescing samples in the solid phase is discussed.

Journal Article↗
PubMed2000

Effect of environmental factors and of the proportion of Holstein blood on the milk yield and lactation length of crossbred dairy cattle on smallholder farms in north-east Tanzania.

A study was carried out on the lactation performance of crossbred dairy cattle in a smallholder farming system in north-east Tanzania. Data were collected from the records for 6 years and the factors considered were district, proportion of Holsteins, season of calving, year of calving and herd size. The data were considered separately for animals with a single lactation record. The least-square means for first lactation length and yield were 331 days (SD 77.0) and 2332 L (SD 283.0), respectively, while for cows with data on more than one lactation record the yield was 2477 L (SD 840.1) in 324 days (SD 74.0). First lactation yield was significantly affected by year of calving. For repeated records, the lactation yield was significantly affected by district, proportion of Holsteins and herd size, while lactation length was significantly affected by district and herd size. The calculated repeatabilities for lactation yield and length were 0.27 and 0.12, respectively. For the pooled data, the correlation between lactation length and yield gave r = 0.569 (p < 0.0001).

Animals↗
PubMed1998

Yield, protein, and oil quality of soybean genotypes selected for tofu production.

The soyfood industry prefers some soybean [(Glycine max L. (Merr.)] cultivars over others based on chemical constituents, physical traits, and processing quality of the seed. However, soybean cultivars possessing the combination of desirable agronomic traits and biochemical characteristics that enhance the quality of soyfoods have not been identified in the USA. Thus, this research was conducted with the objective of determining yield, seed protein, and fatty acid composition of soybean genotypes selected for tofu production. Twelve soybean genotypes were planted in plots arranged in a randomized complete block design with four replications at the Agricultural Research Station, Fort Valley State University, Georgia, USA during 1994 and 1995. Seed yield ranged from 1.6 to 3.0 metric tons/ha. The protein content varied between 314.2 and 480.7 g/kg seed. Both BARC-8 and BARC-9 had significantly higher protein content than other genotypes. These two genotypes also showed significant year by genotype interactions for some fatty acids. V71-370 had the highest oleic acid concentration and a high ratio (0.92) of monounsaturated to polyunsaturated fatty acids. The concentration of linoleic and linolenic acids ranged from 406.5 to 531.0 and 37.1 to 63.0 g/kg oil, respectively. Seed yield was correlated with biomass, harvest index, and filled pods per m2. In this study, V71-370 was found to be relatively superior in oil quality with fatty acid composition desirable for human consumption. The significant variation for seed yield and biochemical characteristics observed among the few genotypes examined in this study indicates the potential for breeding high yielding soybean cultivars suitable for soyfoods. Therefore, there is a need for evaluation of soybean germplasm for agronomic traits that contribute to seed yield and biochemical characteristics including fatty acid profiles that enhance soyfood quality before initiating development of suitable cultivars for tofu.

Fatty Acids↗
PubMed2002

Assessing effects of ambient ozone on injury and yield of bean with ethylenediurea (EDU): three years of plant monitoring at four sites in The Netherlands.

EDU (ethylenediurea) and non-EDU-treated bean plants (Phaseolus vulgaris L. cv. Lit) were exposed to ambient air at four rural sites in The Netherlands during the growing seasons of 1994 through 1996 to investigate the responses to ambient ozone. Ozone-induced foliar injury was observed each year and differences in injury between sites depended on year. On average, injury amounted to 27% in 1994, to 8% in 1995 and to 1% in 1996. Injury increased with increasing ozone exposure (AOT40) and the estimated AOT40 value corresponding with 5% injury was circa 3650 nl l(-1) h ozone. The highest ozone levels accumulated at each site for five consecutive days before injury exceeded the proposed short-term critical level for injury development. EDU reduced injury and its protective effect was positively related to the injury intensity in non-EDU-treated plants. Yield of green marketable pods (intermediate harvest) and mature pods (final harvest) was generally reduced in non-EDU-treated plants compared to EDU-treated plants and differences in yield reduction between harvests varied between years. The yield of mature pods was reduced in 1994 and 1996 while the yield of green pods was reduced in 1995 by ozone only. Since yield reduction was not correlated with AOT40. the EDU method was not valid to determine an ozone exposure-yield reponse relationship for bean.

Air Pollutants↗
PubMed2003

Improved islet yields from Macaca nemestrina and marginal human pancreata after two-layer method preservation and endogenous trypsin inhibition.

We tested whether two-layer method (TLM) pancreas preservation and trypsin inhibition (Pefabloc) during processing allows longer preservation while retaining or improving viable islet recovery. Non-marginal primate (Macaca nemestrina) and marginal human (ischemic or preservation-injured) pancreata were processed with a research-oriented pan technique (Seattle method). Organs were processed upon arrival (+/- Pefabloc), or after TLM or University of Wisconsin solution (UW) preservation (+ Pefabloc). Islet yield, viability, and function were assessed. Pefabloc increased M. nemestrina islet yields from 9696 +/- 1749 IE/g to 15 822 +/- 1332 IE/g (p < 0.01). Two-layer method preservation (< 6 h) further increased yields, to 23 769 +/- 2773 IE/g (vs. + Pefabloc; p < 0.01). Similarly, Pefabloc increased marginal human islet yields from 2473 +/- 472 IE/g to 4723 +/- 1006 IE/g (p < 0.04). This increase was maintained after lengthy TLM preservation (> 30 h; 4801 +/- 1066 IE/g). We also tested the applicability of TLM preservation (23.5 +/- 3.2 h) to the processing of marginal human pancreata by the Edmonton/Immune Tolerance Network clinical protocol. Islet yield and function approached published results of pancreata processed 4.8 +/- 0.8 h after organ recovery (p = 0.06). Pefabloc, and TLM vs. UW preservation, prolonged the tolerable interval between organ recovery and islet isolation. Islet yield, viability, and functionality improved from both marginal and nonmarginal pancreata.

Animals↗
PubMed2026

Grain protein and yield stability study in rainfed durum wheat RILs.

Developing durum wheat cultivars with stable grain yield across diverse environments remains a key breeding objective. This study evaluated 118 recombinant inbred lines (RILs) derived from a cross between the drought-adapted cultivar 'Zardak' (Triticum durum) and the landrace 'Iran-249' (T. turanicum) with desirable seed characteristics, across four heterogeneous rainfed environments in Italy and Iran. The assessment focused on grain yield (GY) and grain protein content (GPC) stability. Combined analysis of variance revealed significant (p&#x2009;<&#x2009;0.01) effects for genotype, environment, and their interaction for both traits. Line ZD-050 showed the highest GY (3.91 t ha&#x207b;&#xb9;), while ZD-032 had the highest GPC (14.27%). Stability analysis using parametric and non-parametric methods, along with AMMI and GGE biplot modeling, identified ZD-050 as among the most promising genotypes according to yield-integrating and dynamic-stability approaches. This line showed high grain yield in methods such as the Superiority Index and Kang's rank-sum, although stability rankings differed across the used methods. This line maintained superior yield, demonstrated broad adaptability across environments, and had moderate protein levels, identifying it as an optimal candidate for breeding programs targeting yield stability and wide adaptation under rainfed conditions.

Triticum↗
PubMed2002

Screening panoramic radiography of new adult patients: diagnostic yield when combined with bitewing radiography and identification of selection criteria.

OBJECTIVES: To measure the radiological diagnostic yield on screening panoramic radiographs taken of new adult patients and to identify selection criteria for panoramic radiography of new adult patients. DESIGN: Survey of 1,817 consecutive panoramic radiographs taken as 'routine' on new patients with statistical analysis of clinical and radiological findings. SETTING: All radiographs were obtained from 41 general dental practitioners (GDPs). The GDPs provided the clinical information about the patient obtained by history and examination. Collection of material occurred in 1998/1999. MATERIALS AND METHODS: Two dental radiologists recorded the radiological findings on each of 1,817 panoramic radiographs by consensus. Those findings that would have been identified from bilateral posterior bitewing radiographs of each patient were then excluded to give modified figures for radiological findings. MAIN OUTCOME MEASURES: Indices of diagnostic yield were devised and calculated for each radiograph from the data on radiological findings. Total diagnostic yield (DY) and modified diagnostic yield (MDY), after exclusion of findings identifiable on bitewing radiographs, were both calculated. Clinical indicators of a high MDY were identified using stepwise multiple regression analysis. RESULTS: MDY was 0 for 17% of the radiographs (all patients) and 23% of the radiographs when the asymptomatic group were considered. The clinical variables for which the significance was high (p < 0.001) were: increasing number of teeth with clinical suspicion of periapical pathology, presence of partially erupted teeth, increasing number of clinically evident carious lesions, partially dentate status and presence of crowns. CONCLUSION: Taking posterior bitewing radiographs of new adult patients would reduce the diagnostic yield identified solely by panoramic radiography. Using clinical factors derived from the history and examination as radiographic selection criteria modestly improves the odds of achieving a high diagnostic yield from panoramic radiography.

Adult↗
PubMed2006

Quantum yields for OH production in the photodissociation of HNO(3) at 248 and 308 nm and H(2)O(2) at 308 and 320 nm.

The quantum yields for OH formation from the photolysis of HNO(3) were measured to be (0.88 +/- 0.09) at 248 and (1.05 +/- 0.29) at 308 nm and of H(2)O(2) to be (1.93 +/- 0.39) at 308 and (1.96 +/- 0.50) at 320 nm. The quoted uncertainties are at the 95% confidence level and include estimated systematic uncertainties. OH radicals were produced using pulsed laser photolysis and monitored using pulsed laser-induced fluorescence. Quantum yields were measured relative to the OH quantum yields from a reference system. The measured quantum yields at 248 nm are in agreement with previous direct determinations. The quantum yield values at 308 and 320 nm are the first direct quantum yield measurements at these wavelengths and confirm the values currently recommended for atmospheric model calculations. Rate coefficients (at 298 K) for the OH + H(2)O(2) and OH + HNO(3) + M (in 100 Torr of N(2)) reactions were measured during this study to be (1.99 +/- 0.16) x 10(-12) cm(3) molecule(-1) s(-1) and (1.44 +/- 0.12) x 10(-13) cm(3) molecule(-1) s(-1), respectively.

Hydrogen Peroxide↗
PubMed2002

Osmolyte accumulation: can it really help increase crop yield under drought conditions?

Osmolyte accumulation (OA) is frequently cited as a key putative mechanism for increasing yields of crops subjected to drought conditions. The hypothesis is that OA results in a number of benefits that sustain cell and tissue activity under water-deficit conditions. It has been proposed as an effective tolerance mechanism for water deficits, which could be enhanced in crops by traditional plant breeding, marker-assisted selection or genetic engineering, to generate drought-tolerant crops. However, field studies examining the association between OA and crop yield have tended to show no consistent benefit. The few, often-cited, investigations with positive associations were obtained under severe water deficits with extremely low yields or conditions with special water-supply scenarios when much of the benefit is plant survival. Under conditions where water deficits threaten crop survival, yields are so low that even large fractional yield gains offer little practical benefit to growers. Indeed, the often-cited benefit of turgor maintenance in cells is likely to result in crop behaviour that is exactly opposite to what is beneficial to crops. The one clear mechanism identified in this review for beneficial yield responses to OA is in the maintenance of root development in order to reach water that may be available deeper in the soil profile.

Journal Article↗
PubMed2000

Diagnostic yield of bronchoscopic sampling methods in bronchial carcinoma.

OBJECTIVES: The aim was to study the yield of malignant or suspicious cells from bronchoalveolar lavage (BAL), endobronchial biopsy (BX) and endobronchial brushing (BR) specimens obtained at bronchoscopy. METHODOLOGY: We prospectively followed up all patients who had undergone bronchoscopy and studied those with subsequent diagnosis of bronchial carcinoma at a tertiary referral centre. Bronchoalveolar lavage, BX and BR were performed, sequentially whenever possible, by one pulmonologist. The parameters assessed were age, gender, macroscopic bronchoscopic findings, TNM staging, radiological findings, histological typing, and diagnostic yield from BAL, BX, and BR. RESULTS: One hundred patients (31 females, 69 males; mean age +/- SD, 61.8+/-12.7 years; range 32-81 years) were studied between 1995 and 1997. Of these, BAL, BX and BR were performed on 100, 64 and 37 cases which yielded diagnostic specimens for bronchial carcinoma in 69, 78.1, and 62.2% of cases, respectively (P > 0.05). Diagnostic specimens were therefore obtained in 69,50, and 23% of the entire patient cohort from BAL, BX, and BR, respectively (P < 0.001). The diagnostic yield of BAL was independent of patient age, gender, site of lesion, TNM staging, histological typing and macroscopic bronchoscopic findings. Addition of BX, BR and postbronchoscopic sputum sampling to BAL only increased the yield of diagnostic specimens for bronchial carcinoma by 7, 0, and 4%, respectively. CONCLUSION: Bronchoalveolar lavage is a highly effective sampling method to obtain cytological evidence for bronchial carcinoma. The diagnostic yield for BAL is independent of tumour or other clinical characteristics. Further studies should be performed to confirm these important and clinically relevant findings.

Adult↗
PubMed2000

Immunomagnetic selection of CD34+ cells: factors influencing component purity and yield.

BACKGROUND: In immunomagnetic selection of CD34+ cells from HPC transplants, not all factors that affect yield and purity of CD34+ cells are known. METHODS: Forty-three consecutive procedures of immunomagnetic selection of CD34+ cells from peripheral blood HPCs and bone marrow harvests (autologous harvests, n = 27; allogeneic harvests; n=16) were performed by use of a cell selection system (Isolex 300i, Baxter Immunotherapy). The composition of the starting component and the subsets of CD34+ cells were analyzed for correlation with the yield and purity of the final component. RESULTS: The mean purity of the final components was 84.3 percent (range, 27-99%), and the mean yield was 51.4 percent (range, 9.4-80. 4%). Partial regression analysis showed that, among the factors correlating with purity and/or yield, the RBC volume in the starting fraction had the highest predictive impact on the purity and yield of CD34+ cells, even after the exclusion of procedures using bone marrow harvests as an HPC source (beta coefficient, -0.704; p = 0. 001). CONCLUSION: The use of the Isolex 300i system allows efficient recovery of CD34+ cells in routine selection procedures. The volume of RBCs in the starting component should be minimized to ensure a high yield and purity of the final component.

Antigens, CD34↗
PubMedDate not supplied

Excretion rate of progesterone in milk and faeces in lactating dairy cows with two levels of milk yield.

This study was conducted to measure the effect of the level of daily milk yield on the excretion rate of progesterone (P4) in milk and faeces in high-producing (HP) and low-producing (LP) lactating dairy cows. A GnRH-agonist was implanted to block endogenous production of P4. A CIDR device was inserted into the vagina and left in place for 11 days. The average and peak milk yields were greater in HP cows (P < 0.0001). Mean plasma concentrations of P4 were also similar in both groups (P = 0.44), even though the average mass of P4 delivered from a CIDR device was higher with HP cows (P = 0.02). Average milk P4 concentration was similar in both groups (P = 0.81), so that average daily excretion of P4 in the milk was greater with HP cows (P = 0.05). The concentrations (P = 0.83) and daily yields (P = 0.4) of total faecal progesterone metabolites were not affected by level of milk yield. These data show that the concentrations of plasma and milk P4, and the concentration and yield of P4 metabolites are not affected by the levels of daily milk yield.

Administration, Intravaginal↗
PubMed2006

Yield of advanced adenoma and cancer based on polyp size detected at screening flexible sigmoidoscopy.

BACKGROUND & AIMS: Observational screening of the colon with subsequent referral for colonoscopy raises questions about the threshold of polyp size that necessitates referral. To examine the yield at colonoscopy when a given size lesion is observed, we assessed the yield of advanced adenoma and cancer at colonoscopy based on the size of the abnormality detected at flexible sigmoidoscopy (FSG). METHODS: We used data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, a randomized, controlled, community-based study of FSG. RESULTS: Subsequent colonoscopy was performed on 10,850 subjects (60.4% male; mean age, 62.9 years) with a polyp visualized on screening FSG. For women with a polyp 0.5-0.9 cm on FSG (n = 1426), the yield in the distal colon on colonoscopy was 0.6% for cancer (number needed to screen [NNS] = 166) and 14.5% for advanced adenoma (NNS = 7). In men (n = 2183), the yield was 0.7% (NNS = 142) for cancer and 15.9% (NNS = 6) for advanced adenoma. Among persons with polyps 0.5-0.9 cm identified on FSG, 5.5% (198/3609) had distal advanced adenomas that measured <1.0 cm but had villous histology or high-grade dysplasia, and 9.9% (357/3609) had adenomas > or =1 cm. CONCLUSIONS: The yield for a distal advanced adenomatous lesion when a polyp 0.5-0.9 cm is observed at FSG is substantial and is due to the presence of advanced histology in polyps <1 cm and to detection of polyps that measure > or =1.0 cm on colonoscopy. Establishing thresholds for observation versus evaluation will require careful assessment of the overall yield.

Adenoma↗
PubMed1988

Diagnostic yield of the autopsy in a university hospital and a community hospital.

To determine the extent to which autopsies yield unexpected findings that are relevant to the patient's death and whether cases with a high yield of such findings can be identified selectively, we studied a total of 233 autopsies at a university hospital and at a community hospital. The rates at which autopsies detected major unexpected findings whose premortem diagnosis would probably have improved survival were 11 percent at the university hospital and 12 percent at the community hospital. Major unexpected findings whose premortem diagnosis would not have prolonged survival were found in another 12 and 21 percent of cases, respectively. Pulmonary embolism and fungal infections in immuno-compromised hosts were the most common major unexpected findings. Neither we nor the patients' physicians were able to identify from the clinical data the autopsies likely to have high yields. Furthermore, the physicians' estimates of an autopsy's expected yield were similar for patients evaluated by autopsy and for matched patients who were not. We conclude that the autopsy continues to yield clinically relevant findings at a high level and that it is not currently possible to predict which cases will have high yields. Autopsies are vital to ensure the quality of medical care, and autopsy rates must be increased substantially if this role is to be fully realized.

Adolescent↗