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51.
Wolfram an der Heiden Bertram Krumm 《European archives of psychiatry and clinical neuroscience》1985,234(5):319-324
Zusammenfassung In Mannheim wurde im Jahre 1968 mit dem schrittweisen Aufbau eines gemeindenahen psychiatrischen Versorgungssystems begonnen. Bestandteil dieses Versorgungskonzepts sind Absprachen zwischen den beteiligten stationären Einrichtungen, die die Zuweisung der Patienten zur stationären Behandlung regeln. Eine modellgestützte, multivariate Analyse von Inanspruchnahmedaten einer Kohorte von 126 schizophrenen Patienten weist nach, daß die Ungleichverteilung der Geschlechter auf die Institutionen das Ergebnis dieser Absprache ist; dabei sind Krankheitsdauer und die Art der Zuweisung von entscheidender Bedeutung.Die vorliegende Arbeit entstand im Rahmen eines von der Deutschen Forschungsgemeinschaft geförderten Projekts im Sonderforschungsbereich 116 Psychiatrische Epidemiologie der Universität Heidelberg (Sprecher: Prof. Dr. Dr. M. Schmidt) 相似文献
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The effect of intermittent seizures on the pyramidal neurons of the hippocampus is largely unknown. To determine whether recurrent seizures centered in the hippocampus can produce neuronal loss in this region, a morphometric analysis was performed from standardized sections of hippocampus using 5 groups of animals: (1) surgical control subjects, (2) rats kindled by the rapidly recurring hippocampal seizure (RRHS) paradigm, (3) kindled rats with a few additional limbic seizures (528 +/- 66 seizures), (4) kindled rats with many limbic seizures (1,523 +/- 130 seizures), and (5) rats experiencing limbic status epilepticus (SE) induced by "continuous" hippocampal stimulation. The RRHS and SE protocols induced significant neuronal loss in the CA1 region, but no evidence was found for additional cell loss with increasing numbers of intermittent seizures. These intermittent seizures were, however, associated with a significant thickening of the basal and apical dendritic fields of the CA1 region. These findings indicate that intermittent seizures produce no significant hippocampal neuronal loss and may result in a hypertrophy of CA1 dendritic fields. 相似文献
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Tierney S Nakeeb A Wong O Lipsett PA Sostre S Pitt HA Lillemoe KD 《Annals of surgery》1999,229(2):205-209
OBJECTIVE: To test the hypothesis that progesterone alters sphincter of Oddi and gallbladder function and, therefore, bile flow dynamics. SUMMARY BACKGROUND DATA: Although the effects of progesterone on the biliary tract have been implicated in the increased incidence of gallstones among women, the specific effects of prolonged elevation of progesterone levels, such as occurs with contraceptive progesterone implants and during pregnancy, on the sphincter of Oddi and biliary flow dynamics are still incompletely understood. METHODS: Adult female prairie dogs were randomly assigned to receive subcutaneous implants containing either progesterone or inactive pellet matrix only. Hepatic bile partitioning and gallbladder emptying were determined 14 days later using 99mTc-Mebrofenin cholescintigraphy. RESULTS: Significantly less hepatic bile partitioned into the gallbladder in progesterone-treated than in control animals. The gallbladder ejection fraction was significantly reduced from 73+/-6% in controls to 59+/-3% in the progesterone-treated animals. The rate of gallbladder emptying was significantly reduced from 3.6+/-0.3%/minute to 2.9+/-0.1%/minute. CONCLUSIONS: Progesterone administered as subcutaneous implants alters partitioning of hepatic bile between gallbladder and small intestine and, therefore, gallbladder filling. Progesterone also significantly impairs gallbladder emptying in response to cholecystokinin. The effects of progesterone on the sphincter of Oddi and the gallbladder may contribute to the greater prevalence of gallstones and biliary motility disorders among women. 相似文献
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Michelle M Kett Warwick P Anderson John F Bertram Daine Alcorn 《Clinical and experimental pharmacology & physiology》1996,23(Z3):132-135
- 1 There is strong evidence for a renal basis to the development of hypertension in the spontaneously hypertensive rat (SHR). Alterations of the SHR renal vasculature, including the glomerulus, may be involved in the initiation and maintenance of hypertension in this animal model.
- 2 The arterial walls of pre-glomerular vessels of the SHR are hypertrophied compared with WKY vessels. Unlike other vascular beds in the SHR, this hypertrophy is independent of angiotensin II (AngII).
- 3 Glomerular number and volume are similar between SHR and the normotensive Wistar-Kyoto (WKY) rats. These results provide no support for the theory that a reduced filtration surface area within the kidneys of the SHR contributes to the elevated blood pressure in these animals.
- 4 Intrarenal hypertrophy may have similar haemodynamic consequences to clipping of the main renal artery, as in Goldblatt hypertension. Further analysis of the role of pre-glomerular arterial hypertrophy is warranted to determine its involvement in the initiation and maintenance of hypertension in the SHR.
59.
E. Bertram E. H. Farthmann 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1981,355(1):393-397
Zusammenfassung Prospektiv-kontrollierte Studien sind die verläßlichsten Hilfsmittel, mit denen klinische Fragestellungen entschieden werden können. Für ihre korrekte Handhabung gibt es eine Fülle strenger Voraussetzungen, die sich in der Praxis meist nicht verwirklichen lassen. In diesen Fällen auf Forschung ganz zu verzichten, hieße sich in fataler Weise von einer Methode abhängig machen. Das Anwendungsgebiet retrospektiver Analysen umfaßt daher vor allem diesen Bereich im Sinne einer zweitbesten Lösung. Darüber hinaus ist der retrospektiven Betrachtungsweise eine innere Notwendigkeit für die medizinische Forschung eigen, wenn man auf kritische Reflexion des eigenen Tuns und auf das Angehen neuer Probleme Wert legt. 相似文献
60.
The oriental microhymenopteran wasp, Gryon triatomaeMasner, 1975 was reared in eggs of triatomine bugs, including vectors of Chagas' disease. In particular, G. triatomae was maintained for 31 generations in eggs of Triatoma maculata (Erichson). Only one parasite develops in each bug egg and 30 to 40 days are required for completion of development at 24 ± 1 °C. Mean parasitization rate of 7484 eggs of T. maculata, in 54 rearings, was 34·7% with a range from zero to the highest rate of 86·7%. Mated females produce predominantly female progeny (mean sex ratio, 1 male : 6·7 females). Unmated females produce parthenogenetic males. The wasp reproduces in fertile eggs, from those recently laid to those with well-advanced bug embryos. Infertile eggs are not usually parasitized. Both sexes survive for one to two weeks unfed, but for several weeks (up to 16 for females) if fed (on honey). Frequent ovipositions may reduce survival. Successful parasitization by females persisted for about three weeks but declined subsequently.Abortions of developing Gryon were usually 10% or less. Brief comparison with other neotropical triatomine species indicates that eggs of Triatoma spp. are susceptible to G. triatomae; Panstrongylus spp. seem relatively poor hosts, and there is little or no parasitization of Rhodnius spp. 相似文献