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961.
Zusammenfassung Eine neu aufgetretene Dyspnoesymptomatik und eine symmetrische, apikal betonte retikulonodul?re Zeichnungsvermehrung im R?ntgen-Thorax bei jungen rauchenden Erwachsenen müssen an das seltene Krankheitsbild der pulmonalen Histiocytosis X denken lassen. Klinischer Befund, laborchemische- und Lungenfunktionsuntersuchungen zeigen unspezifische Befunde. Neue radiologische Verfahren wie die hochaufl?sende Computertomographie (HRCT) leisten bei gezielter Indikationsstellung eine entscheidende differentialdiagnostische Hilfestellung. Dieser Fall verdeutlicht die M?glichkeit einer Diagnosesicherung durch transbronchiale Biopsien unter Verzicht auf offene Lungenbiopsien. Eine ambulante Diagnostik war m?glich, das h?here Risiko eines operativen Eingriffes konnte vermieden werden. Die Indikation zur Therapie ist nicht gesichert und wird daher durch den Grad der subjektiven bzw. funktionellen Einschr?nkung sowie den Verlauf bestimmt.  相似文献   
962.
963.
PURPOSETo trace the development of the normal fetal temporal bone by means of plain radiography, MR, and CT.METHODSEighteen formalin-fixed fetal specimens, 13.5 to 24.4 weeks'' gestational age, were examined with a mammographic plain film technique, CT, and MR imaging at 1.5 T. Temporal bone development and ossification were assessed.RESULTSThe membranous labyrinth grows with amazing rapidity and attains adult size by the middle of the gestation period. The cochlea, vestibule, and semicircular canals are very prominent and easily recognized on MR images. The otic capsule develops from a cartilage model. Ossification of the otic capsule proceeds rapidly between 18 and 24 weeks from multiple ossification centers that replace the cartilaginous framework. The mastoid, internal auditory canal, vestibular aqueduct, and external auditory canal continue to grow after birth.CONCLUSIONThe study of fetal developmental anatomy may lead to a better understanding of congenital disorders of the ear. Faster MR scanning techniques may provide a method for in utero evaluation of the fetal temporal bone.  相似文献   
964.
Objective: To study the pharmacodynamic and pharmacokinetic properties of oral and intravenous methylergometrine upon uterine motility during menstruation. Study-design: Intra-uterine pressure was measured in six volunteers with a fluid-filled sponge-tipped catheter during menstruation. Methylergometrine was given orally (0.5 mg) or intravenously (0.2 mg) in a cross-over design. Results: After intravenous administration, a fast increase of the frequency of uterine contractions and basal tone occurred with a decrease of amplitude, lasting at least 30 min. Oral administration had a late and less marked effect on uterine motility. An intravenous dose administered 24 h after an oral dose had no effect on uterine motility. Pharmacokinetic data, such as the maximum plasma concentration (Cmax), the time at which Cmax is reached (tmax) and the half-life of absorption (t1/2abs) also demonstrated large individual variations after oral administration. Conclusion: Oral administration of methylergometrine had an unpredictable and late effect on uterine motility on the menstruating uterus, probably due to an unpredictable bioavailability, in contrast with the fast and predictable effect after intravenous administration.  相似文献   
965.
966.
Our objective was to determine whether the diagnosis of microcephaly present at birth is apparent using standard biometry in the second trimester. Fetuses with prenatally suspected microcephaly (biparietal diameter > or = 3 standard deviations below mean) who had a first sonogram prior to 22 weeks' gestation and a confirmation of microcephaly after birth were included in the study. We excluded all fetuses who had neural tube defects or other major associated abnormality that would lead to a suspicion of microcephaly. We therefore included fetuses who either had normal-appearing brains sonographically or intracranial calcifications as the only sonographic abnormality seen prior to 22 weeks' gestation. Seven fetuses met these criteria. One fetus was diagnosed as having microcephaly prior to 22 weeks' gestation. The other six fetuses had a normal head size prior to 22 weeks' gestation and were diagnosed as having microcephaly at 27 weeks' gestation and later. Only one of the seven fetuses had a karyotypic abnormality. We conclude that the prenatal diagnosis of microcephaly is not excluded by normal biometry on second trimester sonography.  相似文献   
967.
968.
969.
We examine major criticisms of studies comparing paraprofessionals' and professionals' therapeutic effectiveness. Such analysis does not support the contention that methodological weaknesses of the studies produced systematic biases against professional therapists. Thus, despite common beliefs to the contrary, the finding that formal training does not predict successful therapy appears sound. We discuss the implications of this finding for research, training, and clinical practice.  相似文献   
970.
Dehydrochlorinated poly(vinylidene chloride) proved to be a conjugated polyene-polyene polymer. Shock compression of the polymer formed a large portion of graphite and trace amounts of diamond and of an unknown carbon. The unknown carbon belongs to the hexagonal crystal system and possesses the cell dimension α0 = 0.338 nm. A comparison with known carbynes was made in terms of the crystalline parameters.  相似文献   
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