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Limited data and an accumulated body of anecdotal experience with the tricyclic class of antidepressants suggest that this group of drugs (especially amitriptyline) may be an effective treatment modality in nonulcerative interstitial cystitis. Both the ease of administration and the relatively rapid onset of relief make these types of drugs appropriate to consider for first-line therapy after bladder distention has failed.  相似文献   
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A review of U.S. press histories reveals a common failure to consider immigration and the formation of an ethnic press as constituent elements of an American culture and addresses the need for a cultural history of the media that breaks with current practices.  相似文献   
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Zusammenfassung In Erg?nzung früberer Untersuchungen wurden von methacrylat-eingebettetem Zugholz- und Normalfasergewebe vonPopulus euramericana cv.regenerata ultradünne Quer- und L?ngsschnitte hergestellt. Die elektronen-mikroskopische Untersuchung zeigt, da? die Zellwand der Zugholzfaser aus Mittellamelle, Prim?rwand, den Sekund?rwandschichten 1 bis 3 sowie einer Immenseitigen Abschlu?lamelle besteht. Die S3 stellt dabei die für Zugholzfaser charakteristische gelatin?se (G-)Schicht dar. Die Struktur dieser G-Schicht kann elektronenmikroskopisch nur durch Herausl?sen des Einbettungsmediums deutlich sichtbar gemacht werden. In solcher Weise behandelte Ultradünnschnitte lassen erkennen, da? die G-Schicht eine Wabenstruktur besitzt, in der einzelne cellulosische Lamellen durch Haftpunkte miteinander verbunden sind. Wahrscheinlich sind die Kammern des Wabensystems mit quellbaren Interlamellarsubstanzen ausgefüllt, die in Verbindung mit der Wabenstruktur die bekannten L?ngszugspannungen im Zugholz verursachen k?nnten. Die Entstehung dieser Spannungen ist sowohl als Folge einer Quellung, wie auch als Folge einer Entquellung der G-Schicht denkbar. Die M?glichkeit von Strukturver?nderungen durch die angewendeten Pr?parations vefahren wird ausführlich er?rtert. Es wird nachgewiesen, da? die beschriebeue Wabenstruktur der G-schicht nicht den wabigen Strukturen entspricht, die sich durch S?urebehandlung in der zentralen Sekund?rwandschicht normaler Faserzellen erzeugen lassen.
The submicroscopic structure of the fibre cellwall in poplar tensionwood
Summary In addition to preliminary investigations, ultrathin cross-and and longitudinal sections of tensionwood and normal wood tissue from Populus euramericana cv. regenerata were investigated. These tissues were embedded in methacrylate and examined with an electronmicroscope. It was found that the cell wall of tensionwood fibres of this species is composed of middle lamella, primary wall, and secondary wall. The latter consists of three layers (S1, S2, S3) and is bordered on the lumen side by a terminating lamella. In tensionwood, the S3 appears as a characteristic gelatinous (G) layer. The detailed structure of this G-layer can be clearly seen only when the embedding material is dissolved, its density being very similar to that of the cellulose lamellae of the G-layer. The methacrylate embedding material having been removed, is was found that the G-layer posseses a honeycomb-structure in which the individual cellulose lamellae are firmly connected at irregularly spaced intervals. It is supposed that the interlamellar spaces of this honeycomb-structured G-layer are filled with substances which are able to swell and shrink. It is postulated here that the inherent tensional strains and the resulting longitudinal contraction of tensionwood fibers and tissue, commonly observed, might be caused by either the swelling or shrinking of interlamellar substances within the G-layer. Swelling might cause longitudinal contraction, if these substances swell mostly in radial direction. This radial swelling results in a radial expansion and, consequently, longitudinal contraction of the individual cavities of the honeycomb structure. On the other hand, the commonly observed longitudinal confraction of tensionwood fibres and tissue might also be explained by shrinking. In this case, the interlamellar substances must be mostly isotropic, and thus their shrinking and consequently that of the tensionwood tissue would occur in all directions. The methods used to establish that the honeycomb structure of the G-layer is not an artifact of the preparation, are also described. It is proven that the G-layer structure as described in this paper is not the same as the honeycomb structure produced by the treating of fibre cells of normal wood tissue with acid.


Beitrag zu den Verhandlungen der Arbeitsgruppe Wood Quality der IUFRO-Sektion 41 in Madison, USA, vom 11. bis 13. September 1963.  相似文献   
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OBJECTIVE: To evaluate the incidence of early pulmonary complications and the value of initial clinical signs and paraclinical investigations in victims of smoke inhalation not suffering from burns following structural fires. DESIGN: Retrospective chart review. SETTING: Thirteen-bed ICU. PATIENTS: Sixty-four victims of smoke inhalation following household fires were admitted to the ICU between January 1987 and December 1992. Exclusion criteria from the study were patients with cutaneous burns or multiple trauma or blast injury, and patients found in cardiac arrest. METHODS: Clinical, biological, and radiologic parameters were collected over a 5-day period. RESULTS: The mortality rate in relation to progressive respiratory failure was 3.1%. Mean ICU stay was 5.8 days (range, 1 to 33 days), and was longer in the patients presenting with soot deposits in the oropharynx (p = 0.02), dysphonia (D) (p = 0.05), or ronchi (R) (p = 0.0004) at the first examination, and in those having a positive sputum bacteriologic analysis (p = 0.003) or requiring parenteral bronchodilator agents for more than 24 h (p = 0.04). Thirty-five patients underwent mechanical ventilation (MV) for a mean of 101.2 h (range, 8 to 648 h). Mean MV duration was higher in the patients presenting initially with R (p = 0.003), high carbon monoxide (but not cyanide) levels (p = 0.02), or a positive bacteriologic sample (p = 0.0001). Positive bacteriologic sampling correlated with the presence of D (p = 0.02) or R (p = 0.04) and with immediate intubation (p = 0.0003). No correlation was found with chest radiograph. CONCLUSIONS: In this selected series of fire victims without cutaneous burns, respiratory injury was frequent. The initial clinical signs may be helpful to predict pulmonary complications.  相似文献   
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The safety and tolerability of single escalating doses of lubeluzole were evaluated in healthy male volunteers in 2 studies. In the first of 2 randomized, single-blind, placebo-controlled, dose-escalation studies, 6 subjects received single 30-minute infusions of 2.5, 5, and 10 mg of lubeluzole, and 2 additional subjects received placebo. In the second study 6 different subjects received a 1-hour infusion of 15 mg of lubeluzole, 5 of whom received the 20-mg dose, and 2 received 25 mg of lubeluzole. Two additional subjects received placebo. Small increases and decreases in PQ, QRS, QT, QTc, and QTm intervals were noted after infusion of all lubeluzole doses and placebo, however, these changes were within the normal ranges for these values except for the QTc for the 25-mg dose of lubeluzole. Significant prolongation of the QTc interval was observed at the end of the 1-hour infusion in both subjects receiving the 25-mg dose of lubeluzole. No clinically relevant changes in systolic time intervals, heart rate, blood pressure, and clinical laboratory values were noted in subjects receiving 2.5-25 mg of lubeluzole or placebo. Adverse experiences, predominantly lightheadedness and dizziness, were reported by subjects receiving doses of lubeluzole greater than or equal to 10 mg. Lubeluzole, administered as single intravenous doses of 2.5-15 mg, is safe and well tolerated in healthy male volunteers.  相似文献   
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