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N-heterocyclic carbenes (NHCs) found numerous applications as ligands for transition metal complexes during the last two decades. Only recently, however, increasing attention is turning to high oxidation state organometallics with NHC ligands. A surprising number of stable complexes of that type have been described mainly during the last five years and several of them have potential for application in both homogeneous and heterogeneous catalysis of organic reactions. This article describes the preparation and characteristics of these high oxidation state organometallic complexes with NHC ligands and gives an outlook on their possible applications.

Objectives:To evaluate antifungal terbinafine in patients with chronic rhinosinusitis.

The complexes (η⁵-C5R5)MoO2Cl (R = H, CH3 (Me), CH2Ph (Bz)) are readily prepared from the parent carbonyls (η⁵-C5R5)Mo(CO)3Cl upon reaction with t-BuOOH (TBHP) in n-decane. The compounds are characterized by vibrational spectroscopy, ¹H, ¹³C, and ⁹⁵Mo NMR spectroscopy, and elementary analysis and are compared to their (η⁵-C5R5)ReO3 homologues. The Mo−C5R5 force constants have been determined. (η⁵-C5Bz5)MoO2Cl can be stored and handled at room temperature without decomposition, in contrast to the more temperature sensitive Cp (R = H) and Cp* (R = Me) analogues. The (η⁵-C5R5)MoO2Cl complexes catalyze the epoxidation of cyclooctene, styrene, and 1-octene with TBHP as oxidizing agent. The highest activity is found for (η⁵-C5Bz5)MoO2Cl:  TOF 21000 mol/(mol × h) for cyclooctene in CH2Cl2 at 55 °C with a ratio catalyst:substrate:TBHP = 0.0001:1:2.5. This activity even surpasses that of the well-known MeReO3/H2O2 system. The stable parent carbonyls (η⁵-C5R5)Mo(CO)3Cl can be used as catalyst precursors since they are transformed into (η⁵-C5R5)MoO2Cl under the operating catalytic conditions.

Abstract: Background: Trauma remains a major problem throughout the world. The prognosis of severe eye injuries is commonly bleak. This paper focuses on the epidemiology of eye trauma, the role of ocular epidemiology, and identification and reduction of risk factors.  Methods: An analysis of the first 8,952 patients reported with severe eye injuries, defined as those eye injuries resulting in permanent and significant (measurable and observable on routine eye examination) structural and/or functional changes to the eye, from the United States Eye Injury Registry as of 31 July 1998.  Results: The age of patients entered was from the 1st year of life to 103 years. Fifty-eight percent of those injured were less than 30 years of age. The male to female ratio was 4.6:1, reaching 7.4:1 in the fourth decade of life. Almost half of the injuries involved the retina, and 77% of the injured eyes required one or more surgical procedures, including a large proportion which have undergone vitreoretinal surgical procedures.  Conclusion: Injuries remain the most serious public health problem facing developed nations. Yet, a persistent inadequacy exists both in the standardized documentation of eye injuries and in their treatment. With appropriate surgical and medical intervention, a majority of the reported injured eyes recovered functional levels of visual acuity. It appears that glasses, including prescription glasses and even non-prescription sunglasses, can offer measurable protection which results in a lower incidence of severe eye injuries to those wearing glasses.

17 patients with intraretinal magnetic foreign bodies and vitreous hemorrhage are reported. 15 patients underwent a primary surgical repair consisting of a watertight wound closure and removal of the already swelling cataractous lens in 5 cases. All patients had vitrectomy during the second postinjury week. The foreign body was left in place in 2 cases and removed with intravitreal forceps in 15 patients. Total or partial retinal attachment was achieved in 12 patients (71%). Details of the surgical procedure are described.

In a 65-year-old patient with slowly progressive myelopathy of the lower spinal cord MRI revealed slight thickening of the conus medullaris and discrete serpiginous areas of low signal intensity in contact to the surface of the myelon. The T2-weighted axial images demonstrated a zone of high signal intensity within the center of the lumbosacral cord. These findings corresponded to the results of autopsy: cord enlargement, dilatation of wallthickened and partially thrombosed pial veins, edema, damage of the myelin sheath with development of foam cells, areas of hemorrhage and necrosis. Although myelography and spinal digital subtraction angiography had been normal in this case we assume that perhaps a spinal dural av-fistula may have been the cause of MR- and pathological findings which indicate an angiodysgenetic myelomalacia (Morbus Foix-Alajouanine). The pathogenesis of spinal dural av-fistulas is discussed in order to explain why angiography has been negative.

Activated hydrogen peroxide produces very reactive OH-radicals which destroy hazardous contaminants in water. The principles and different methods of activation are described. Results from laboratory studies show the numerous applications of this new technology. A successful scaleup of laboratory tests to an industrial level is discussed. Finally, a cost estimate for treating different types of water with hydrogen peroxide is presented.

Eighteen patients with atherosclerotic disease of the aorto-iliac bifurcation were treated with percutaneously implantable, balloon expandable tantalum stents. Stenting indications were percutaneous transluminal angioplasty (PTA) —resistant stenoses and long aorto-iliac occlusions. The vascular prostheses were inserted by bilateral femoral approach and dilated simultaneously, their proximal parts being deployed in parallel in the aorta and their distal parts anchored in the common iliac arteries (kissing-stent method). In aorto-iliac occlusions, local fibrinolysis was used to facilitate guide wire passage. Within 20 months (the duration of longest observation), no major acute or late complications occurred. Clinical symptoms improved immediately in all patients. Deterioration of clinical symptoms during the follow-up period was observed in five patients and was due to additional, newly developed atherosclerotic disease located distally, the bifurcation stents remaining patent.

Summary Preoperative ultrasound, CT-scanning, arteriography and endoscopic retrograde cholangiopancreaticography have improved the diagnostic approach to abdominal and vascular diseases. The correlation between preoperative imaging and intraoperative findings sometimes is difficult. In these cases intraoperative ultrasound can be helpful. The application of B-ScanRealtime-Ultrasonography during surgery will give additional information on vascular diseases, control of vascular anastomoses, on intraoperative flowmeasurement, localization of tumors in the liver and pancreas and on defining margins of resection. Intraoperative sonography is a new device for the surgeon, which should be used to control the site of abdominal tumors as well as vascular anastomoses.

Over the centuries, the management of eyes with intraocular foreign bodies (IOFB) has posed a special challenge to the physician, and the anxiety created by such injuries has never abated. During the past few decades, several new diagnostic tests, IOFB removal techniques, and methods to treat the complications of the injury have been introduced. Nevertheless, old habits die hard: many of the management options that used to be standard are not appropriate any more but have proved difficult to change. This article reviews over forty of these die-hard myths and confronts them with factual statements published in the peer-review international literature.

Mixed imido/oxo rhenium(VII) complexes, formal derivatives of methyltrioxorhenium(VII) (1) with (2,6-diisopropylphenyl)imido ligands of general formula CH3ReO3-x(NR)x (x = 1, and 2; compounds 2 and 3, respectively), have been synthesized. Their structures and behavior in solution have been studied by dynamic ¹H and ¹⁷O NMR spectroscopy. In the solid state, compounds 2 and 3 display dimeric structures, as shown by X-ray crystallography. In solution, monomeric and dimeric forms exist in equilibria. At elevated temperatures, the monomers are dominant. In the solid state, the dimeric compounds are bridged by oxygen ligands, forming Re2O2 units, while in solution, nitrogen bridging is also evident. Formal replacement of all three oxo groups in 1 by (2,6-diisopropylphenyl)imido ligands leads to a compound of formula CH3Re(NR)3 (4). Complex 4 is monomeric both in solution, regardless of the temperature, and in the solid state. Ligand exchange processes take place via dimeric intermediates if organorhenium oxides are mixed with organorhenium(VII) imido/oxo species or organorhenium(VII) imides. Reaction of methylbis(imido)monooxorhenium(VII) (3) with (methylcyclopentadienyl) trioxorhenium (5) leads to a dimer with mixed methyl/cyclopentadienyl and imido/oxo groups (6). Reaction of 2−4 with water slowly leads to the formation of 1, perrhenate, and amines.

A novel compound, KFM 19, is introduced, which turned out to be a selective adenosine A1-antagonist with good bioavailability. Its pharmacological profile suggests a high therapeutic potential for dementia and related cognitive deficits.

Die bei einem neuzeitlichen Drucklufthammer auftretenden Bewegungen des Hammerkörpers werden in Abhängigkeit von der jeweils aufgebrachten Anpreßkraft beschrieben. Der gesamte Arbeitsbereich wird in Stufen aufgeteilt, die dabei entstehenden Rückstoßarten definiert und in einem Grundschema wiedrgegeben. Es wird eine Methode zur Registrierung des Kraftverlaufes beschrieben, der beim Arbeiten mit Druckluftschlagwerkzeugen zwischen Hammergriff und haltender Hand auftritt, und die es erlaubt, die Beaufschlagung der menschlichen Hand zu beurteilen. Durch zusätzliche Bewegungs-, Beschleunigungs-und Zeitmessungen wird eine Beziehung zwischen der Rückstoßkurve und dem Hammerspiel hergestellt. An einem vorliegenden Oszillogramm wird ein schwerer Abbauhammer und seine Arbeitsweise analysiert.

Die Rückstoßkräfte und die Rückstoßwege, die beim Arbeiten mit dem Preßlufthammer auftreten, hängen nicht nur von der Konstruktion des Hammers und dem bearbeiteten Material, sondern auch von dem dynamischen Verhalten des Menschen ab. Zur Charakterisierung dieser mechanischen Eigenschaft des Menschen wird der Begriff der mechanischen Impedanz des Menschen bei der Arbeit mit dem Preßlufthammer eingeführt. Unter Verwendung eines Schütteltisches wurde diese komplexe Größe ihrem absoluten Betrag und ihrer Winkelgröße (= „Nacheilwinkel”) nach bei sinusförmigen Frequenzen zwischen 10 und 70 Hz gemessen. In grober Näherung kann nach den Meßergebnissen der Mensch bei der Abbauhammerarbeit als ein geschwindigkeitsproportionaler Reibungswiderstand von 0,2 kg sec/cm betrachtet werden, sofern nur Frequenzen unter 100 Hz berücksichtigt werden. Die Unterschiede, die sich aus der Armhaltung ergeben, sind relativ gering.

Ohne Zusammenfassung:

Die epicorticalen Makropotentiale vom Gyrus pericruciatus und Gyrus suprasylvianus anterior bei Reizung im vorderen und hinteren Kopfanteil des Nucleus caudatus wurden an 53 Katzen systematisch untersucht. Die Reizantworten zeigen einen zeitabhängigen Aufbau: nach einer Latenzzeit von höchstens 2 msec stellt sich zumeist eine primäre Positivität ein, der eine primäre Negativität und unter besonderen Bedingungen eine sekundäre Negativität folgen. Regelmäßig schließt sich eine Folgepositivität an. Den Abschluß bildet die Spindelgruppe. Durch Repetitions-, Interaktions- und Hypoxieversuche konnte gezeigt werden, daß den einzelnen Komponenten Selbständigkeit zukommt. Ausführlich werden auch die topographischen Besonderheiten herausgearbeitet.

Die Makropotentiale bei gleichzeitiger Reizung und Ableitung im Nucleus caudatus („intracaudatale“ Reizantworten) wurden systematisch an 55 Katzen untersucht. Unabhängig vom Reiz- und Ableiteort innerhalb des Caudatums zeigten die Potentiale einen relativ konstanten zeitabhängigen Aufbau: Entweder unmittelbar nach dem Reizeinbruch oder nach einer kurzdauernden Negativität stellt sich immer eine primäre Positivität mit einer mittleren Gipfellatenz von 40 msec ein. Ihr kann eine Negativität mit einer Gipfellatenz von 10 msec aufgelagert sein. Regelmäßig schließt sich eine Folgenegativität an, deren mittlere Gipfellatenz 71 msec beträgt. Häufig findet sich nach dieser Komponente eine Folgepositivität, die zur Spindelgruppe überleitet.

For fear of endophthalmitis and siderosis, ferrous intraocular foreign bodies are usually removed as soon as they are discovered; markedly reduced, siderotic ERG changes are considered permanent. We report a patient who presented with a chronically retained intravitreal foreign body and significant clinical as well as electrophysiologic signs of siderosis. Only 3 months after surgery, the ERG showed almost complete recovery. If siderosis is not present, adequate and regular follow-up examinations may in certain cases substitute for immediate removal of chronically retained intraocular foreign bodies.