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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
In striatal membranes bearing significant levels of histamine H3 receptors (72 +/- 14 fmol/mg protein), the H3 agonist immepip (1 microM) increased [35S]GTPgammaS binding to 119 +/- 2% of basal, an effect prevented by the H3 antagonist clobenpropit and by pre-treatment with pertussis toxin. In slices labelled with [3H]adenine and in the presence of 1 mM isobutylmethylxantine (IBMX), the selective dopamine D1-like (D1/D5) receptor agonist SKF-81297 stimulated cyclic [3H]AMP ([3H]cAMP) accumulation (maximal stimulation 205 +/- 24% of basal, EC50 113 +/- 12 nM), an effect fully blocked by the D1/D5 antagonist SCH-23390. The accumulation of [3H]cAMP induced by 1 microM SKF-81297 was inhibited in a concentration-dependent manner by the selective H3 receptor agonist immepip (maximal inhibition 60+/-5%, IC50 13 +/- 5 nM). The inhibitory action of 100 nM immepip was reversed in a concentration-dependent manner by the H3 antagonist thioperamide (EC50 13 +/- 3 nM, Ki 1.4 +/- 0.3 nM). Forskolin-induced [3H]cAMP accumulation (726 +/- 57% of basal) was also reduced by H3 receptor activation, although to a lesser extent (19.1 +/- 3.2% inhibition), an action not affected by the absence of either IBMX or Ca2+ ions in the incubation medium. Neither the density of [3H]SCH-23390 binding sites (D1 receptors) nor the inhibition by SKF-81297 were affected by 1 microM immepip, ruling out a direct interaction between D1 and H3 receptors. These results indicate that through H3 receptors coupled to Galphai/o proteins, histamine modulates cAMP formation in striatal neurones that possess D1 receptors, most probably GABAergic striato-nigral neurones. 相似文献
992.
Durand-Joly I Aliouat el M Recourt C Guyot K François N Wauquier M Camus D Dei-Cas E 《Journal of clinical microbiology》2002,40(5):1862-1865
The infectious power of Pneumocystis carinii f. sp. hominis was explored by inoculating SCID mice intranasally with either P. carinii f. sp. hominis or P. carinii f. sp. muris isolates. Only mice inoculated with mouse parasites developed Pneumocystis pneumonia, as assessed by microscopy and PCR. These results suggest that humans do not contract pneumocystosis from animals. 相似文献
993.
J. Tamarelle A.C.M. Thiébaut B. de Barbeyrac C. Bébéar J. Ravel E. Delarocque-Astagneau 《Clinical microbiology and infection》2019,25(1):35-47
Background
The vaginal microbiota may modulate susceptibility to human papillomavirus (HPV), Chlamydia trachomatis, Neisseria gonorrhoeae and Mycoplasma genitalium infections. Persistent infection with a carcinogenic HPV is a prerequisite for cervical cancer, and C. trachomatis, N. gonorrheae and M. genitalium genital infections are all associated with pelvic inflammatory disease and subsequent infertility issues.Objectives
To evaluate the association between these infections and the vaginal microbiota.Data sources
The search was conducted on Medline and the Web of Science for articles published between 2000 and 2016.Study eligibility criteria
Inclusion criteria included a measure of association for vaginal microbiota and one of the considered STIs, female population, cohort, cross-sectional and interventional designs, and the use of PCR methods for pathogen detection.Methods
The vaginal microbiota was dichotomized into high-Lactobacillus vaginal microbiota (HL-VMB) and low-Lactobacillus vaginal microbiota (LL-VMB), using either Nugent score, Amsel's criteria, presence of clue cells or gene sequencing. A random effects model assuming heterogeneity among the studies was used for each STI considered.Results
The search yielded 1054 articles, of which 39 met the inclusion criteria. Measures of association with LL-VMB ranged from 0.6 (95% CI 0.3–1.2) to 2.8 (95% CI 0.3–28.0), 0.7 (95% CI 0.4–1.2) to 5.2 (95% CI 1.9–14.8), 0.8 (95% CI 0.5–1.4) to 3.8 (95% CI 0.4–36.2) and 0.4 (95% CI 0.1–1.5) to 6.1 (95% CI 2.0–18.5) for HPV, C. trachomatis, N. gonorrhoeae and M. genitalium infections, respectively.Conclusions
Although no clear trend for N. gonorrhoeae and M. genitalium infections could be detected, our results support a protective role of HL-VMB for HPV and C. trachomatis. Overall, these findings advocate for the use of high-resolution characterization methods for the vaginal microbiota and the need for longitudinal studies to lay the foundation for its integration in prevention and treatment strategies. 相似文献994.
Vincent Thomas-de-Montpréville Rémi Nottin Elisabeth Dulmet Alain Serraf 《Cardiovascular pathology》2007,16(1):22-28
BACKGROUND: Heart tumors are rare lesions with variegated histological types. Their clinicopathological features could be more comprehensively categorized. METHODS: This is a 19-year retrospective study of 17 infants/toddlers (<2 years of age) and 42 patients aged between 14 and 79 years (mean = 51.5) in a surgical center. RESULTS: Congenital tumors (n = 17; 29%), including rhabdomyomas (n = 9), ventricular fibromas (n = 6), and hemangiomas (n = 1), required surgery mainly because of mass effect. Familial myofibromatosis was the only embolic congenital lesion. Acquired benign tumors (n = 28; 47%) included myxomas (n = 21), fibroelastomas (n = 3), myofibroblastic inflammatory tumors (n = 2), and lipomas (n = 2). Eight (29%) were revealed by systemic embolization. These benign noncongenital tumors were all treated by complete resection, except for an incompletely resected lipoma of the mitral valve. Postoperative arrhythmia (n = 1) and pericardial effusion (n = 3) were the only complications. Primary sarcomas (n = 8; 14%) were mostly vascular tumors (five of eight), and patients with high-grade tumors had a mean survival of 15 months (n = 5). Cardiac metastases (n = 6; 10%) were from carcinomas (n = 3) or sarcomas (n = 3); apart from a necrotic metastasis, all patients died (mean survival of 6 months). CONCLUSIONS: This study shows that, regardless of patients' age, heart tumors can be classified as: (a) congenital lesions, which are spontaneously nonprogressive or regressive lesions possibly requiring surgery mainly because of mass effect; (b) acquired benign tumors, which are lesions requiring surgery often because of embolization risk; and (c) primary and secondary malignant tumors, which are lesions with globally poor prognosis but with some indications for resection. 相似文献
995.
996.
Y. Bouchet J. P. Bodin A. Pissas M. Favier A. Dupré J. Champetier J. L. Peralta 《Surgical and radiologic anatomy : SRA》1980,2(4):343-349
Résumé L'évidement axillaire peut être envisagé soit à titre préventif et systématique dans la chirurgie du cancer ou à titre curatif dans les affections du contenu de la fosse axillaire. Sa réalisation opératoire doit tenir compte de la morphologie de la lame cellulo-adipeuse de l'aisselle, moulée autour du paquet vasculo-nerveux entouré de sa gaine et de l'importance de ses prolongements vers le creux sus-claviculaire, voie de passage des courants lymphatiques.La position opératoire du membre supérieur facilite l'abord de la base de la pyramide et l'exérèse totale de son contenu sans sacrifice cutané ou musculaire et sans séquelle motrice.Le repérage des divers éléments de la lame cellulo-adipeuse doit permettre à l'anatomo-pathologiste d'apprécier la localisation exacte des ganglions lymphatiques. 相似文献
997.
The magnocellular mesencephalic nucleus (MMN) of Gymnotus carapo was studied by electron microscopy. This particular nucleus, characteristic of weakly electric fish, contains two principal classes of neuron. (1) Large neurons (25-35 mum): these are rounded unipolar cells, with the perikaryon partially covered by a sheath of compact myelin. The axon leaves the neuron as a short thick unmyelinated process not resembling the initial segment of multipolar neurons. The axon branches profusely and becomes myelinated very close to its origin. The perikaryal surface not covered by the myelin sheath receives abundant club endings. The synaptic interface between club endings and large neurons is characterized by alternating gap junctions and attachment plaques. In addition, at the periphery of the club endings, "active" zones are generally present, and this synapse is therefore a "mixed" synapse. (2) Small neurons (5-12 mum): these are uni- or bipolar cells, scattered throughout the nucleus, and occasionally, grouped in small clusters. Gap junctions were not observed between neuronal perikarya in such clusters. The synaptic investment of small neurons is formed by long cup endings which almost completely encircle the perikarya. The synaptic interface between cup endings and the perikarya of small neurons is characterized by large areas of gap junctions. A single cup ending establishing gap junctions with two small neurons within the plane of the section was frequently observed and this arrangement provides a morphological basis for electrotonic coupling between small neurons by way of presynaptic fibres. In the neuropil of the MMN, there are abundant synaptic islands constituted by a large axon terminal in synaptic contact with small unidentified profiles; both synaptic elements are surrounded by numerous thin glial lamellae. At the synaptic interface, in the islands, both gap junctions and "active" zones are present. The synaptic islands must also be considered as "mixed" synapses. The morphological results presented here correlate with electrophysiological data (Szabo et al., 1975). The very short delay (0.8-1.3 ms) of the MMS response to the fish's own electric organ discharge can only be explained by the existence of electrotonic transmission along the neuronal chain of the electrosensory pathway. The presence of gap junctions between club endings and large neurons provides a morphological basis for electrotonic transmission at the mesencephalic level of the electrosensory pathway. 相似文献
998.
999.
1000.
Millogo A Lankoandé D Yaméogo I Yaméogo AA Sawadogo A Sawadogo AB 《Bulletin de la Societe de pathologie exotique (1990)》2004,97(4):268-270
Seizures are common in advanced stages of immunodeficiency virus (HIV) infection. HIV-infected outpatients and inpatients in the national hospital in Bobo-Dioulasso among whom seizures occurred had been recruited over four years. There were mainly male (30/13) with an average age of 35 years with extremes ranging from 22 to 60 years. New-onset generalised seizures occurred in all cases of cryptococcal meningitis or partial motor secondary generalised in 64% among patients with suspected cerebral toxoplasmosis due to the efficiency of the treatment of the antitoxoplasmic proof. Identified causes such as suspected cerebral toxoplasmosis (65%), suspected tuberculous meningitis (7%) as CSF culture is not available, cryptococcal meningitis (16%) were found in this study. In four cases among 43 patients, no identified causes could be determined. CD4 lymphocytes count which was available in 24 patients was under 200/41 in 74% of the cases. This study indicates clearly that seizures in young adults are strongly associated with focal brain lesions and cerebral toxoplasmosis is becoming an important cause of seizure in tropical area. This should imply a screening of toxoplasmosis with new-onset seizure in young people. 相似文献