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1.
The topography of the auriculotemporal nerve (ATN) root system is the main criterion of this nerve classification. Previous publications indicate that ATN may have between one and five roots. Most common is a one- or two-root variant of the nerve structure. The problem of many publications is the inconsistency of nomenclature which concerns the terms “roots”, “connecting branches”, or “branches” that are used to identify the same structures. This study was performed on 80 specimens (40 adults and 40 fetuses) to propose a classification based on: (i) the number of roots, (ii) way of root division, and (iii) configuration of interradicular fibers that form the ATN trunk. This new classification is a remedy for inconsistency of nomenclature of ATN in the infratemporal fossa. This classification system has proven beneficial when organizing all ATN variants described in previous studies and could become a helpful tool for surgeons and dentists. Examination of ATN from the infratemporal fossa of fetuses (the youngest was at 18 weeks gestational age) showed that, at that stage, the nerve is fully developed.  相似文献   
2.
The presence of 17 alpha-hydroxylase in rodent adrenals is debated. The presence in blood of mice of 11-deoxycortisol together with the absence of cortisol is well known. We demonstrated here the in vitro synthesis of 17 alpha-hydroxyprogesterone and cortisol from [3H]progesterone in rat and mouse adrenals. We have shown that these syntheses represented 45 and 28% of those of 11-deoxycorticosterone and corticosterone, respectively, from progesterone. These data clearly suggest the presence of a 17 alpha-hydroxylase activity in vitro in these rodents adrenals. In addition, a noticeable synthesis of cortisol (0.87-1.57% per mg tissue, i.e. 52-64% per incubation flask) from 11-deoxycortisol was also observed and was inhibited by 0.1-0.3 mumol of Metyrapone and SKF 12185. These results allow to underline that the adrenals of rat and mouse, two species commonly used in laboratory experiments, may be used for in vitro investigations on cortisol metabolism from exogenous radioactive precursors.  相似文献   
3.
A Auzéby  A Bogdan  Y Touitou 《Steroids》1991,56(1):33-36
17-Hydroxyprogesterone is a well-known precursor of androstenedione in adrenal biosynthesis. This study using sheep adrenal incubations demonstrates that 11-deoxycortisol, the precursor of cortisol synthesis, also can be a precursor of androstenedione. Indeed, our data show that androstenedione synthesis is negatively correlated to the synthesis of cortisol and cortisone. This fact allowed us to infer that this new pathway is closely related to the activity of the 11 beta-hydroxylase that is responsible for the synthesis of cortisol. Indeed, when the activity of this enzyme is impaired, 11-deoxycortisol follows the pathway that leads to androstenedione synthesis in the adrenals. This pathway could explain, at least in part, the marked increase of androstenedione observed in congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency.  相似文献   
4.
The effect of cyclosporin A (CyA) application on the development of cutaneous lesions was analyzed in genetically susceptible BALB/c mice infected s.c. with Leishmania tropica promastigotes. Daily i.p. injections of CyA, beginning 2 days before or at the day of the infection, dose dependently inhibited the development of parasite-induced lesions; no effect on the lesions was observed, however, if CyA application was started 14 days after the infection. Cessation of CyA administration after having successfully suppressed the cutaneous lesions for a period of 42 days, resulted in the development of lesions within 3 days. CyA had no inhibitory effect on lesions developing in L. tropica infected hypothymic BALB/c nu/nu mice. CyA or CyA-containing mouse serum did not directly affect the viability and the growth rate of L. tropica promastigotes, suggesting that the effect of the agent was imposed on the cells participating in the formation of the cutaneous lesions. Quantitative analysis of the cell distribution in the spleens of infected mice revealed that CyA markedly suppressed the infection-associated numerical increase of splenocytes. Within the Thy-1+ lymphocyte compartment, CyA had its most pronounced effect on the Lyt-1+ T lymphocyte subset. Early in the disease, the frequency of splenic cells proliferating in response to L. tropica antigen in vitro was clearly inhibited by CyA; in the later stages of the infection, however, this effect could not be observed, indicating the presence of L. tropica-inducible T cells being relatively resistant to CyA. Taken together, our findings indicate that CyA reversibly inhibits or delays the parasite-induced expansion of Lyt-1+ splenic T lymphocytes, and thus suppresses the biological function of those T cells that are instrumental for the formation of cutaneous lesions in L. tropica-infected BALB/c mice.  相似文献   
5.
A combined method is described for the determination of various metabolites from a single tissue sample of the brain. It comprises a quick inactivation of cerebral enzymes by microwave irradiation, easy separation of the desired brain regions, and perchloric acid extraction of tissue substances, which are assayed either by specific enzymatic techniques or by HPLC with electrochemical detection. The obtained values of most energy and neurotransmitter metabolites in the brain are in agreement with those reported using other methods. However, this technique, in contrast to the brain freezing in vitro or freeze-blowing, provides a more efficient procedure for rapid arrest of cerebral metabolism even in the deep brain structures and is therefore suitable for detection of early changes particularly those occurring in experimental pathological conditions such as ischemia.  相似文献   
6.
Résumé Par un jeûne de trois jours ou par l'administration per os de réserpine(2 à 4 mg/kg) durant 15 à 24 jours, on a provoqué des ulcères d'estomac chez des rats. Une partie des bÊtes ainsi traitées fut exposée durant cette période et pendant 2 heures par jour à un air ionisé contenant 5.000 à 15.000 petits ions par cm3 d'air. Pour les animaux soumis au jeûne, la proportion d'ulcères se monte à 93% chez les bÊtes de contrÔle, alors qu'elle n'est que de 59% chez les bÊtes traÎtées par l'air ionisé. Pour les rats traÎtés à la réserpine, les proportions sont de 83,respectivement de 45%. On a en outre exposé 66 patients atteints d'ulcères d'estomac et d'intestins durant 12 à 15 jours et pendant 15 à 45 minutes par jour à un air contenant 5.000 à 10.000 petits ions négatifs par cm3 d'air. Pour 38 d'entre eux, la douleur et les autres symptÔmes avaient diminué ou disparu après le traitement.
Gastric ulcers were produced in rats by starvation for 3 days or the administration of reserpine (2 to 4 mg/kg) for 15 to 24 days. Some of the animals were exposed to ionized air for 2 hours daily during these periods(5,000 to 15,000 small negative ions/m3 air). The incidence of ulcer development was 93% in the untreated starved rats and 59% in those treated with ionized air; 83% in the animals treated with reserpine and 45% in those with additional ionized air treatment. In a clinical investigation 66 patients with peptic ulcer were exposed for 12 to 15 days to 5,000 to 10,000 small negative ions/m3 air daily. Pain and other symptoms were diminished or abolished after this treatment in 38 patients.

Zusammenfassung Bei Ratten wurden durch 3 Tage Hungern oder Behandlung mit Reserpin (2–4 mg/kg) wÄhrend 15 bis 24 Tagen Magenulcera provoziert. Ein Teil der Tiere wurde wÄhrend dieser Perioden 2 Std. tÄglich ionisierter Luft exponiert (5.000–15.000 kleine Ionen/m3 Luft). Die Ulcusrate betrug bei den unbehandelten Hungertieren 93%, bei den mit ionisierter Luft behandelten 59%; bei den Reserpin behandelten Tieren betrug sie 83% und bei den zusÄtzlich mit ionisierter Luft behandelten 45%. In der Klinik wurden 66 Patienten mit Magen-Darmulcera 12–15 Tage lang 15–45 min tÄglich mit 5.000 –10.000 neg. kleinen Ionen/m3 Luft behandelt. In 38 Patienten waren nach der Behandlung der Schmerz und die anderen Symptome abgeschwÄcht oder verschwunden.
  相似文献   
7.
Acute megakaryoblastic leukaemia (AMkL) is a rare subtype of acute myeloid leukaemia (AML) representing 5% of all reported cases, and frequently diagnosed in children with Down syndrome. Patients diagnosed with AMkL have low overall survival and have poor outcome to treatment, thus novel therapies such as CAR T cell therapy could represent an alternative in treating AMkL. We investigated the effect of a new CAR T cell which targets CD41, a specific surface antigen for M7-AMkL, against an in vitro model for AMkL, DAMI Luc2 cell line. The performed flow cytometry evaluation highlighted a percentage of 93.8% CAR T cells eGFP-positive and a limited acute effect on lowering the target cell population. However, the interaction between effector and target (E:T) cells, at a low ratio, lowered the cell membrane integrity, and reduced the M7-AMkL cell population after 24 h of co-culture, while the cytotoxic effect was not significant in groups with higher E:T ratio. Our findings suggest that the anti-CD41 CAR T cells are efficient for a limited time spawn and the cytotoxic effect is visible in all experimental groups with low E:T ratio.  相似文献   
8.
Zusammenfassung Die ArtAsperula scutellaris Vis. wurde diagnostisch erweitert und genauer präzisiert. Sie zerfällt in folgende Sippen: die typische Form ssp.illyrica Korica, welche zwei Varietäten umfaßt (var.veleensis Korica und var.montenegrina Korica), und ssp.ramiflora Korica mit einer Varietät (var.albanica Korica).Asperula scutellaris Vis. ist ein mediterran-illyrischer Endem und einer der bemerkenswertesten Vertreter der jugoslawischen und albanischen Karstflora. Im mittleren Teil Albaniens tritt sie auch auf Serpentinen auf.In pflanzengeographischem Sinn sind vier Entwicklungsgebiete dieser Art zu unterscheiden: das Entwicklungsgebiet der Veleplanina in der Herzegowina (var.veleensis), das montenegrinische Entwicklungsgebiet (var.montenegrina) mit dem ursprünglichen Ausbildungszentrum in der weiteren Umgebung der Stadt Cetinje, endlich das nordalbanische Entwicklungsgebiet im Stromgebiet der Flüsse Cijevna und Drim. Diese drei Gebiete sind von submediterranem Charakter, das mittelalbanische Entwicklungsgebiet in der Gegend des Flusses Shkumbi (var.albanica) weist dagegen einen mediterranisch-submediterranischen Charakter auf.Auf Grund der festgestellten Tatsachen des heutigen Standes der Verbreitung der einzelnen Sippen dieser Art sowie auf Grund der charakteristischen geomorphologischen und klimatischen Differenzen zwischen den monomorphen Sippen (ssp.illyrica), welche an die Küstenteile des beschriebenen Areals gebunden sind, und den polymorphen Übergangsformen der submediterranen Sippen, welche in den kontinentalen Teilen des Areals überwiegen (submediterrane klimatische Einflüsse), folgt, daß die typischen Formen (ssp.illyrica) im submediterranen Gebiet phylogenetisch nicht mit jenen des mediterranen Gebietes identisch sind.  相似文献   
9.
Thrombin is a potent mitogen for human vascular smooth muscle cells (HVSMC) and its enzymatic activity is required for this function. The present study demonstrates that prothrombin is also mitogenic for HVSMC due to the generation of enzymatically active thrombin which occurs upon incubation of prothrombin with the cells. Analysis by SDS-PAGE, immunoblotting, and amino acid sequencing revealed that prothrombin incubated with HVSMC undergoes limited proteolysis. Prethrombin 1 was formed through cleavage at R155-S156. Cleavage at R271-T272 generated fragment 1.2 and prethrombin 2 whilst cleavage at R284-T285 yielded truncated prothrombin 2 (prethrombin 2′). However, cleavage at R320-I321 which, during prothrombin activation produces two-chain α-thrombin, was not detectable. Studies on HVSMC-conditioned medium revealed that a similar pattern of prothrombin cleavage occurred by a cell-secreted factor(s). Amidolytic activity analysis indicated that 1–3% catalytically active thrombin-like activity was generated upon incubation of prothrombin with HVSMC-conditioned medium. By treating conditioned medium with various classes of proteinase inhibitors or hirudin, it was determined that prothrombin is cleaved by a cell-derived serine proteinase-like factor(s) at R271-S272 and by α-thrombin at R155-S156 and R284-T285. Antibodies neutralising the activity of either urokinase, tissue plasminogen activator, or factor Xa failed to alter the prothrombin cleaving activity of conditioned medium. This activity which may catalyse an alternative pathway for the generation of thrombin, was eluted from a gel filtration column as a single peak with apparent molecular mass of 30–40 kDa. © 1995 Wiley-Liss, Inc.  相似文献   
10.
Hydration of macromolecules and the structure of water of crystallization are not understood in detail because in these complex systems. H-atoms cannot be located and the hydrogen bonding schemes are not known. X-ray and neutron diffraction studies on a hydrated oligosaccharide, α-cyclodextrin 6H2O, ((C6H10O5)6·6H2O), crystals forms A and B, gave insight into the chain-like and circular arrangement of hydrogen bonds. In the circles, homodromic (unidirectional) and antidromic (counter-running) orientation of five to six hydrogen bounds is observed. PCILO calculations showed that homodromic circles and chains are approx. 8% per hydrogen bond more stable than antidromic circles, that the changes in electronic charges on H and O atoms are greater in homo than in antidromic systems and that the dipole moments are only approx. 3 D in the homodromic circles but 6–8 D in chain-like and antidromic arrangement. These results have been interpreted in terms of cooperative effect. Circular systems are considered as structural elements in hydration shells of macromolecules and in the assembly of ‘flickering’ water clusters.  相似文献   
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