Is vertebral body stenting in combination with CaP cement superior to kyphoplasty?

PURPOSE: In the evolution of the minimally invasive treatment of vertebral compression fractures, vertebral body stenting (VBS) was developed to reduce intraoperative and secondary loss of vertebral height. Particularly in combination with the usage of biodegradable cement, the influence of VBS on the rate of intraoperative complications and long-term outcome is unclear. The purpose of this study was to investigate the differences between balloon kyphoplasty (BKP) and VBS regarding their long-term clinical and radiological outcome in combination with calcium phosphate (CaP) application instead of polymethyl methacrylate (PMMA). METHODS: This retrospective study included 49 patients with fresh mono-segmental thoracolumbar fractures without neurological signs treated with VBS or BKP and CaP cement (Calcibone). The outcome was evaluated with the visual analogue pain scale (VAS), the Oswestry disability score (ODI), and radiologically assessed. RESULTS: In the course of the radiological follow-up, the VBS group showed statistically significant less vertebral height loss than the BKP group. However, with respect to VAS and ODI scores there were no statistically significant differences between the VBS and BKP group in the clinical follow-up. The rate of cement leakage was comparable in both groups. CONCLUSIONS: Both techniques facilitated good clinical results in combination with absorbable cement augmentation. In particular, the VBS enabled us to benefit from the advantages of the resorbable isothermic CaP cement with an improved radiological outcome in the long term compared to BKP. However, there was a mentionable loss of reduction in the follow-up in both groups compared to previously published data with PMMA cement. These slides can be retrieved under Electronic Supplementary Material.

Influence of gonadotrophin-induced first oestrus on gilt fertility.

The aim of this study was to determine the association between the oestrous response of pre-pubertal gilts to gonadotrophin injection or boar exposure and their subsequent farrowing rate and litter size. At 154 days of age, randomly selected pre-pubertal gilts received an intramuscular injection of 400 IU equine chorionic gonadotrophin plus 200 IU human chorionic gonadotrophin (PG600(®) ; Merck Animal Health; n = 181). From the remaining pool of animals not treated with hormones, the first gilts showing signs of oestrus were selected to act as controls (n = 201). Boar exposure began at 155 days of age for both groups, and gilts were bred at a weight of approximately 130 kg. Comparisons were made between PG600(®) -treated gilts exhibiting oestrus or not within 7 days post-injection (early and late responders, respectively) and control gilts exhibiting oestrus or not within 30 days after beginning of boar exposure (select and non-select control gilts, respectively). By 162 days, oestrus was detected in 67.5% of PG600(®) -treated gilts compared with 5.7% of control gilts (p < 0.0001). The proportion of animals observed in oestrus at least three times before breeding was greater for select control gilts compared with early and late responder PG600(®) -treated gilts (p ≤ 0.001). There were no significant differences in farrowing rate and litter size between the four treatment groups. These data indicate that PG600(®) is an effective tool to induce an earlier oestrus in gilts, that subsequent farrowing rate and born alive litter size compare favourably to that of select gilts and that gilts failing to respond promptly to hormonal stimulation do not exhibit compromised fertility.

Endosonographic elastography in the diagnosis of mediastinal lymph nodes.

BACKGROUND AND STUDY AIMS: Ultrasonographic elastography is a new technique for describing the mechanical properties of tissue during real-time ultrasonography. The aim of this study was to test the feasibility of this method in endosonography (EUS) of the dorsal mediastinum, and to compare the elastographic patterns of lymph nodes with results from EUS-guided fine-needle aspiration biopsy (FNAB). PATIENTS AND METHODS: 50 consecutive patients undergoing EUS-guided FNAB of at least one paraesophageal lymph node were included. Each of these targeted lymph nodes was examined also elastographically. The elastographic patterns were described and compared with the histologic results by a first examiner. The elastographic classification was subsequently further tested by two blinded reviewers. RESULTS: In total, 66 lymph nodes were examined; 37 lymph nodes revealed benign and 29 malignant tissue at the histologic evaluation. Good elastographic records were obtained for all lymph nodes. Of the 37 benign lymph nodes, 31 showed a homogeneous pattern of intermediate elasticity, whereas a dominance of hard tissue with variable patterns was found in 23 of 29 malignant lymph nodes. Applying these criteria, the accuracy range among the three examiners was between 81.8 % and 87.9 % for benign lymph nodes and between 84.6 % and 86.4 % for malignant ones. The interobserver agreement was excellent (kappa = 0.84). CONCLUSION: EUS elastography of mediastinal lymph nodes can be performed reliably. The results are good for a noninvasive technique, but they remain inferior to the success rate of EUS-guided FNAB. The method might occasionally be useful for targeting the most suitable lymph nodes for FNAB.

Evaluation of the optimal standardized ileal digestible tryptophan:lysine ratio in lactating sow diets.

Three hundred and fifteen primiparous and multiparous sows were evaluated in a study to determine the effect of standardized ileal digestible (SID) Trp:Lys ratio in lactating sow diets. Camborough sows (PIC USA, Hendersonville, TN) ranging from first parity to eighth parity were blocked by parity and randomly allotted to 1 of 4 experimental diets containing different levels of added L-Trp (0.006, 0.026, 0.045, and 0.064%, respectively) while soybean meal, 30% corn dried distiller's grain with solubles (DDGS), and L-Lys levels were held constant. The SID Lys level for the rations was 0.95% so that the SID Trp:Lys ratios were formulated to be 14, 16, 18, and 20%, respectively. All diets were formulated to have 3.2 Mcal ME/kg and to contain vitamins and minerals that exceeded NRC (1998) recommendations. Sows were fed twice a day with a Howema computerized feed system and were allowed a maximum intake (5.9 kg/d). Average daily feed intake had a tendency to be quadratically improved when the SID ratio was increased (5.11, 5.28, 5.24, 5.21 kg/d, P = 0.09). In addition, sow wean to estrus (6.71, 5.53, 5.58, 6.33, P < 0.02) was quadratically improved as SID Trp:Lys ratio increased. Percent of sows bred by 10 d (84.39, 90.82, 90.28, 90.61) was not linearly (P = 0.25) or quadratically (P = 0.40) improved. There was no difference in litter gain (2.44, 2.52, 2.60, 2.57 kg/d, P = 0.16). Based on a broken-line quadratic model, when sows are fed 30% DDGS, the SID Trp:Lys ratio of 17.6 is required for optimal sow average daily feed intake and 17.2 for wean to estrus interval.

Effect of timing of relocation of replacement gilts from group pens to individual stalls before breeding on fertility and well-being.

Variation in gilt fertility is associated with increased replacement and reduced longevity. Stress before breeding is hypothesized to be involved in reduced fertility. This study tested the timing of gilt relocation from pens to individual stalls before breeding on fertility and well-being. The experiment was performed in replicates on a commercial research farm. After detection of first estrus, gilts ( = 563) were assigned to treatment for relocation into stalls 3 wk (REL3wk), 2 wk (REL2wk), or 1 wk (REL1wk) before breeding at second estrus. Subsets of gilts from each treatment ( = 60) were selected for assessment of follicles at second estrus. Data included interestrus interval, number of services, conception, farrowing, total born, and wean to service interval. Piglet birth weight was obtained on subsets of litters ( = 42/treatment). Measures of well-being included BW, backfat, BCS, lesions, and lameness from wk 1 after first estrus until wk 16. Gilt BW at wk 5 (158.4 kg) was not affected ( > 0.10) by treatment. Measures of BCS, lameness, and lesions at breeding and throughout gestation did not differ ( > 0.10). Treatment did not affect ( > 0.10) gilts expressing a normal interestrus interval of 18 to 24 d (83.4%) but did influence ( < 0.05) the proportion expressing shorter ( < 0.001) and longer ( < 0.001) intervals. Gilts in REL3wk had a shorter ( < 0.001) interestrus interval (20.7 d) than those in REL2wk and REL1wk (22.6 d). Gilts with shorter intervals ( = 24) had fewer total born while gilts expressing longer cycles ( = 65) had reduced farrowing rates. The number of services (1.9) and number of follicles (19.7) at breeding were not affected ( > 0.10) by relocation. There was no effect of treatment on farrowing rate (85.2%), born alive (12.6), or any litter birth weight measures ( > 0.10). The percentage of sows bred within 7 d after weaning (94.4%) was also not affected by treatment ( > 0.10). These results suggest that the timing of relocation before breeding had no effect on well-being or on the majority of gilts with normal estrous cycles and their subsequent fertility. However, a smaller proportion of the gilts exhibited shorter and longer interestrus intervals in response to relocation 1 or 3 wk before breeding. In cases where gilt fertility may be less than optimal, producers that relocate gilts from pens to stalls before breeding should evaluate interestrus interval as a response criterion.

The feeding of dried distillers' grains with solubles to lactating sows.

Three experiments were conducted to evaluate the feeding of dried distillers' grains with solubles (DDGS) in sow lactation diets. In Exp. 1, 168 multiparous sows (PIC, Camborough 22) were fed a 10% DDGS diet throughout gestation. Sows were randomly allotted to 1 of 4 corn-soybean meal lactation diets formulated to contain different levels of DDGS (0, 10, 20, and 30%, respectively). All diets were formulated to be isocaloric (3.46 Mcal ME/kg) and all other nutrients exceeded NRC (1998) nutrient recommendations. Sow ADFI was not different ( > 0.10) as DDGS level increased. Increasing DDGS resulted in a linear ( < 0.03) increase in sow weight gain (7.5, 11.3, 20.3, and 17.2 kg, respectively) and a reduction in wean-to-first-service interval (7.1, 5.2, 5.0, and 4.9 d, respectively). Increasing DDGS did not affect subsequent total born per litter (13.7, 12.8, 13.3, and 12.3, respectively; > 0.10). In Exp. 2 and 3, lactation diets consisted of corn and 20, 30, 40, or 50% DDGS. Diets were formulated at 3.25 Mcal ME/kg, 1.05% standardized ileal digestible lysine, and all other nutrients to exceed NRC (1998) nutrient recommendations. In both experiments, sows (PIC, Camborough) were fed 40% DDGS in gestation and allocated to a randomized complete block based on the parity of the sow at the time of entry into the farrowing house. In Exp. 2, 256 gilts and multiparous sows were fed the randomly assigned diets. As DDGS inclusion increased, sow feed intake (6.2, 6.2, 6.0, and 5.9 kg/d, respectively) and sow weight gain (10.5, 10.3, 8.2, and 6.2 kg, respectively) tended to linearly decrease ( < 0.06). Sow wean to estrus differed between 20 and 30% DDGS inclusion (4.9 vs. 6.9 d; < 0.01). Litter gain was not different (2.55, 2.53, 2.51, and 2.59 kg/d, respectively; > 0.10) as DDGS inclusion increased. In Exp. 3, 98 multiparous sows were randomly allotted to 1 of the 4 experimental diets during the summer months. Sow feed intake, sow weight gain, and litter gain were not different ( > 0.10) between treatments. The data suggest that feeding high levels of DDGS of 40 to 50% may reduce sow feed intake and litter performance. These results demonstrate that feeding up to 30% DDGS in lactation diets can be done without adversely influencing sow or litter performance.

Energy expenditure and socioeconomic status in Guatemala as measured by the doubly labelled water method.

The energy expenditure of lower (group 1) and upper socioeconomic group females (group 2) from a marginal community in Guatemala City was determined by using the doubly labelled water method. Energy expenditure values were 1925 +/- 66 (mean, SEM) kcal/d (group 1) and 2253 +/- 145 kcal/d group 2 (p less than 0.03). About half of this difference can be attributed to size.

Linguistic ability in early life and the neuropathology of Alzheimer's disease and cerebrovascular disease. Findings from the Nun Study.

Findings from the Nun Study indicate that low linguistic ability in early life has a strong association with dementia and premature death in late life. In the present study, we investigated the relationship of linguistic ability in early life to the neuropathology of Alzheimer's disease and cerebrovascular disease. The analyses were done on a subset of 74 participants in the Nun Study for whom we had handwritten autobiographies completed some time between the ages of 19 and 37 (mean = 23 years). An average of 62 years after writing the autobiographies, when the participants were 78 to 97 years old, they died and their brains were removed for our neuropathologic studies. Linguistic ability in early life was measured by the idea (proposition) density of the autobiographies, i.e., a standard measure of the content of ideas in text samples. Idea density scores from early life had strong inverse correlations with the severity of Alzheimer's disease pathology in the neocortex: Correlations between idea density scores and neurofibrillary tangle counts were -0.59 for the frontal lobe, -0.48 for the temporal lobe, and -0.49 for the parietal lobe (all p values < 0.0001). Idea density scores were unrelated to the severity of atherosclerosis of the major arteries at the base of the brain and to the presence of lacunar and large brain infarcts. Low linguistic ability in early life may reflect suboptimal neurological and cognitive development, which might increase susceptibility to the development of Alzheimer's disease pathology in late life.

Argon plasma coagulation (APC) in gastroenterology: experimental and clinical experiences.

BACKGROUND: Diathermy procedures are indispensable in interventional endoscopy. Argon beam coagulation is an innovative no-touch electrocoagulation technique in which high-frequency alternating current is delivered to the tissue through ionized argon gas. METHOD AND PATIENTS: Before clinical application, we conducted in-vitro studies to investigate the depth and diameters of tissue coagulation in fresh operative specimens from the stomach, small intestine and colon. Five different power/gas flow settings between 40 and 155 W and 2 and 7 l/min were used. The impact time (1-10s) and the incident angle of the probe (45 degrees and 90 degrees) were also varied. The maximum depth of necrosis was 2.4 mm, the maximum diameter 1.1 cm. No perforation occurred even in critical areas such as the colon and duodenum. We therefore performed argon beam coagulation in 66 consecutive patients. Two power/gas flow settings of 40 and 70 W and 2 and 3 l/min, respectively, were used. The impact time and incident angle were varied individually. RESULTS: In 49 of the 50 patients with oozing haemorrhage from angiodysplastic lesions, polypectomy sites, erosions or ulcers or oozing of blood due to vascular penetration by tumours, definitive haemostasis was achieved in one to two sessions. In all 11 patients with residual sessile adenoma tissue, complete removal was possible. Oesophageal patency was restored in all five patients with stenosing tumours. In one patient with angiodysplasia of the caecal pole, an asymptomatic accumulation of gas in the submucosa was observed which resolved spontaneously. In two patients with extensive oesophageal carcinoma, there was a transitory--also asymptomatic--accumulation of gas in the mediastinum and peritoneal cavity but no evidence of perforation. CONCLUSION: Argon plasma electrocoagulation is an effective and relatively low-cost alternative to laser therapy in gastrointestinal endoscopy.

Language decline across the life span: findings from the Nun Study.

The present study examines language samples from the Nun Study. Measures of grammatical complexity and idea density were obtained from autobiographies written over a 60-year span. Participants who had met criteria for dementia were contrasted with those who did not. Grammatical complexity initially averaged 4.78 (on a 0-to-7-point scale) for participants who did not meet criteria for dementia and declined .04 units per year; grammatical complexity for participants who met criteria for dementia initially averaged 3.86 and declined .03 units per year. Idea density averaged 5.35 propositions per 10 words initially for participants who did not meet criteria for dementia and declined an average of .03 units per year, whereas idea density averaged 4.34 propositions per 10 words initially for participants who met criteria for dementia and declined .02 units per year. Adult experiences, in general, did not moderate these declines.

Ultrasound-guided extracorporeal shock wave lithotripsy of pancreatic ductal stones: six years' experience.

Extracorporeal shock wave lithotripsy (ESWL) and endoscopic sphincterotomy (EST) was performed in 35 patients suffering from pancreatic duct stones. Calculi disintegration and resolution of obstruction were achieved in all cases. Completely stone-free ducts were achieved in 16 patients (46%) while some peripheral asymptomatic stone material remained in 19 (54%). Dilation of the main pancreatic duct was reduced in 29 patients (83%). Twelve patients (34%) became completely asymptomatic and 17 (49%) reported a marked reduction of pain. Pancreatogenic steatorrhea ceased and 18 patients (51%) gained weight. Pathological glucose tolerance returned to normal in one patient. No major complications were observed. The combination of ESWL and EST is a successful, nonoperative, new treatment in pancreatic stone disease.

The relationship of self-rated function and self-rated health to concurrent functional ability, functional decline, and mortality: findings from the Nun Study.

We investigated the relationship of self-rated function (i.e., the ability to take care of oneself) and self-rated health to concurrent functional ability, functional decline, and mortality in participants in the Nun Study, a longitudinal study of aging and Alzheimer's disease. A total of 629 of the 678 study participants self-rated their function and health and completed an initial functional assessment in 1991-93. Survivors completed a second assessment in 1993-94. Overall, self-rated function had a stronger relationship to functional ability at the first assessment and to functional decline between the first and second assessments than did self-rated health. Self-rated function also had a stronger relationship to mortality than did self-rated health. Self-rated function may be a better marker of global function than is self-rated health and may be a useful addition to clinical assessment and scientific investigation of the relationships among function, health, and disease.

Self-rated function, self-rated health, and postmortem evidence of brain infarcts: findings from the Nun Study.

OBJECTIVES: Self-rated function is a new global measure. Previous findings suggest that self-rated function predicts future functional decline and is strongly associated with all-cause mortality. We hypothesized that the strength of the relationship of self-rated function to all-cause mortality was in part due to functional decline, such as would occur with brain infarcts. METHODS: Self-ratings of function and health (on a 5-point scale, ranging from excellent to poor) were assessed annually on 630 participants in the Nun Study. Mortality surveillance extended from October 31, 1991 to March 1, 1998, and, among those who died, neuropathological examination determined postmortem evidence of brain infarcts. Cox regression modeling with self-rated function and health as time-dependent covariates and stratification by assessment period were used in these analyses. RESULTS: Self-rated function and health ratings of good, fair, and poor were significantly associated with doubling of the risk of mortality, compared with ratings of very good and excellent. Self-rated function ratings of fair or poor were associated with a threefold increase in the risk of mortality with brain infarcts, but self-rated function and health ratings of fair and poor were comparable in their association with all-cause mortality and mortality without brain infarcts. DISCUSSION: Self-rated function was significantly associated with mortality with brain infarcts, suggesting that brain infarcts may be experienced as functional loss but not recognized or labeled as disease. Our results suggest that self-rated function and health should be explored simultaneously in future research.

The effect of dietary soy daidzein on pig growth and viral replication during a viral challenge.

Twelve replications of four littermate pigs from a porcine reproductive and respiratory syndrome (PRRS) naive herd were weaned (11 +/- 2 d of age) and penned individually in isolation rooms. Pigs were randomly allotted within litter to one of four dietary soy daidzein concentrations (0, 200, 400, or 800 ppm) to quantify the effect of daidzein on growth and immune response during a PRRS challenge. Daidzein was provided as the soy aglycone. At 27 +/- 2 d of age (4.9 +/- 1.4 kg BW), pigs were oronasally inoculated with 10(4.3) PRRS virus/mL from strain JA142 in a 2-mL dose. Blood was collected every 4 d from d 0 to 24 after inoculation and analyzed for serum PRRS virus, interferon, and alpha-1-acylglycoprotein (AGP) concentrations. Serum virus and interferon peaked at 10(5.3) virus/mL and 79% protection, respectively, at 4 d after inoculation and then declined steadily. Serum AGP concentration peaked at 12 d after inoculation. Each log increase in serum virus was associated with an increase in serum interferon, which resulted in a decrease of pig ADG and daily feed intake of 0.019 kg and 0.023 kg, respectively, in 5.8-kg pigs and a feed intake reduction of 0.024 kg in 12.5-kg pigs. Dietary daidzein additions did not (P > 0.3) alter the serum concentration after inoculation of PRRS virus (10(1.79), 10(1.94), 10(1.86), 10(1.93) virus/mL of serum) or AGP. Serum concentrations of interferon responded cubically (30.3, 28.9, 29.4, and 31.1% protection) as dietary daidzein concentrations increased; however, the magnitude of the response decreased over time. Dietary daidzein additions resulted in improvements in daily pig gain, daily feed intake, and gain/feed during periods of peak viremia (d 4 to 16 after inoculation), but not in periods when systemic virus concentrations were minimized (d 16 to 24 after inoculation), resulting in a daidzein x days after inoculation interaction. Based on these data, the magnitude of the growth responses that occur in pigs infected with a virus is quantitatively related to the animal's serum concentration of the virus and interferon, and dietary soy daidzein at 200 or 400 ppm is a weak enhancer of body growth in virally challenged pigs.

Quantitative relationship of systemic virus concentration on growth and immune response in pigs.

Ninety-six pigs from a herd naive for porcine reproductive and respiratory syndrome (PRRS) virus were weaned (10 +/- 3 d of age), penned individually in isolation rooms, and, at 29 +/- 4 d of age, oronasally inoculated with a 2-mL dose of 10(4.3) JA142 PRRS virus/ mL. Body weight; feed intake; and serum concentrations of PRRS virus, interferon, and alpha1-acylglycoprotein were determined for each pig every 4 d on d -8 to 24 postinoculation to quantify the effect of PRRS exposure on the immune response and growth of pigs. Another objective was to determine whether a quantitative relationship between a measure of systemic (serum) virus concentration and pig growth exists. Serum PRRS virus and interferon peaked at 10(5) virus/mL and 69% protection, respectively, at 4 d postinoculation and then declined steadily. Serum alpha1-acylglycoprotein concentration peaked at 12 d postinoculation. Pig weight gains and feed intake were reduced sharply in the initial 8 d postinoculation and to a lesser degree for 24 d postinoculation. The serum concentration of virus and to a lesser degree serum concentrations of interferon and alpha1-acylglycoprotein were quantitatively related to body weight gain and feed intake. The magnitude of the relationship was dependent on the stage of recovery from PRRS infection. Specifically, each log increase in serum virus concentration was associated with a reduction of 4-d pig gain and feed intake of .047 kg and .189 kg, respectively, in 5.5-kg pigs 4 d postinoculation and .085 kg and .036 kg, respectively, in 12.5-kg pigs at 20 d postinoculation. Based on these data, factors that minimize the systemic presence of a virus in pigs result in improvements in pig growth that are quantitatively related to the degree of systemic virus elimination or minimization.

The effect of dietary soy genistein on pig growth and viral replication during a viral challenge.

Twelve replications of four littermate pigs from a herd naive for porcine reproductive and respiratory syndrome (PRRS) were weaned (10 +/- 2 d of age) and penned individually in isolation rooms. Pigs were randomly allotted within litter to one of four dietary soy genistein concentrations (0, 200, 400, and 800 ppm) to quantify the effect of soy genistein on pig growth and virus replication during a viral challenge. Genistein was provided as the soy glycoside, genistin. At 29 +/- 2 d of age (4.9 +/- 1.4 kg BW), pigs were oronasally inoculated with 10(4.3) PRRS virus/mL from strain JA142 in a 2-mL dose. Blood was collected every 4 d from d 0 to 24 postinoculation and analyzed for serum PPRS virus, interferon activity, and alpha1-acylglycoprotein (AGP) concentrations. Serum virus and interferon peaked at 10(5) virus/mL and 57% protection, respectively, at 4 d postinoculation and then declined steadily. Serum AGP concentration peaked at 12 d postinoculation. Each log increase in serum virus was associated with a reduction of daily gain of 0.034 kg in 5.3-kg pigs and 0.004 kg in 11-kg pigs. As dietary genistein concentration increased, serum concentrations of PRRS virus decreased linearly (10(2.46), 10(2.26), 10(2.05), and 10(2.14) virus per milliliter of serum, P < 0.07) and interferon responded quadratically (28.4, 25.7, 22.8, and 30.9% protection, P < 0.06) independent of days postinoculation. The AGP concentrations increased (P < 0.01) quadratically with the magnitude of the response to dietary genistein maximized at 12 to 16 d postinoculation. Effects of dietary genistein on daily pig gain and feed intake were dependent on dietary genistein concentration and stage of viremia. Daily pig gains from d 0 to 24 postinoculation were improved as dietary genistein increased, but the magnitude of the response to dietary genistein concentration lessened as the serum virus concentrations were minimized resulting in a linear genistein x period interaction (P < 0.07). Daily feed intakes also were increased quadratically as genistein concentration increased. These data indicate that soy genistein at dietary concentrations of 200 to 400 ppm is an orally active immune modulator that enhances systemic serum virus elimination and body growth in virally challenged pigs.

A program to measure new energetic particle nuclear interaction cross sections.

The Transport Collaboration, consisting of researchers from institutions in France, Germany, Italy and the USA, has established a program to make new measurements of nuclear interaction cross sections for heavy projectiles (Z > or = 2) in targets of liquid H2, He and heavier materials. Such cross sections directly affect calculations of galactic and solar cosmic ray transport through matter and are needed for accurate radiation hazard assessment. To date, the collaboration has obtained data using the LBL Bevalac HISS facility with 20 projectiles from 4He to 58Ni in the energy range 393-910 MeV/nucleon. Preliminary results from the analysis of these data are presented here and compared to other measurements and to cross section prediction formulae.

Evolution and revolution as organizations grow. 1972.

The influence of history on an organization is a powerful but often overlooked force. Managers, in their haste to build companies, frequently fail to ask such critical developmental questions as, Where has our organization been? Where is it now? and What do the answers to these questions mean for where it is going? Instead, when confronted with problems, managers fix their gaze outward on the environment and toward the future, as if more precise market projections will provide the organization with a new identity. In this HBR Classic, Larry Greiner identifies a series of developmental phases that companies tend to pass through as they grow. He distinguishes the phases by their dominant themes: creativity, direction, delegation, coordination, and collaboration. Each phase begins with a period of evolution, steady growth, and stability, and ends with a revolutionary period of organizational turmoil and change. The critical task for management in each revolutionary period is to find a new set of organizational practices that will become the basis for managing the next period of evolutionary growth. Those new practices eventually outlast their usefulness and lead to another period of revolution. Managers therefore experience the irony of seeing a major solution in one period become a major problem in a later period. Originally published in 1972, the article's argument and insights remain relevant to managers today. Accompanying the original article is a commentary by the author updating his earlier observations.

[Extracorporeal shockwave lithotripsy of bile duct calculi]. / Extrakorporale Stosswellenlithotripsie von Gallengangsteinen.

Shockwave therapy of bile duct stones is not dependent on difficult preconditions concerning stone-volume and -composition or subsequent lythic therapy. Its main indication is failure of endoscopic sphincterotomy (EST). Shockwave lithotripsy of bile duct stones--which may even be carried out even instead of EST in specific cases--is with a success rate of 80 to 95% as effective as shockwave lithotripsy in urology.

[Extracorporeal shockwave lithotripsy of gallbladder calculi]. / Extrakorporale Stosswellenlithotripsie von Gallenblasensteinen.

Shockwave disintegration of gallbladder stones with lythic therapy of residual fragments is successful when all criteria of patient- and stone-selection, shockwave application and lysis are fulfilled. The "Four-S-stones" proved to be the best candidates: solitary, symptomatic, sonolucent in a sufficiently contractile gallbladder. The rate of complications is low. Stone recurrence rate (10 to 15% after three years) is much lower as in previous studies using lythic therapy only. The new therapeutic approach to gallbladder stone disease with fragmentation, spontaneous fragment-clearance and lysis of residual fragments is--as the only truly non-invasive procedure--for 10 to 20% of the patients an alternative equal to operation.