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41.
Angiotensin II receptors in vascular smooth muscle and adrenal cortex have been characterized in the dog. The evidence was derived chiefly from experiments that assessed the ability of a structural analog of angiotensin II, [Sar1, Ile8] AII, to antagonize the effects of exogenously administered angiotensin II on arterial pressure and aldosterone secretion. [Sar1, Ile8] AII is a potent and specific blocker of the pressor response to angiotensinII; in the adrenal cortex, it is a much less effective inhibitor of aldosterone biosynthesis. These results indicate differences in the receptor sites for angiotensin II in vascular smooth muscle and adrenal cortex. Further, they raise the possibility that angiotensin II stimulates aldosterone secretion by mechanisms other than have already been proposed. 相似文献
42.
c-JUN-like immunoreactivity in the CNS of the adult rat: basal and transynaptically induced expression of an immediate-early gene 总被引:3,自引:0,他引:3
An immunocytochemical study of dorsal root ganglia, spinal cord and medulla oblongata was performed with antisera against the c-jun proto-oncogene encoded protein. The c-JUN-like immunoreactivity was restricted to the cell nucleus. In the CNS of untreated rats a basal c-JUN-like immunoreactivity was present in the nuclei of two types of neurons: motor and autonomic. Labelled nuclei could be seen in many motoneurons of the ventral horn of the entire length of spinal cord and the lower medulla oblongata, as well as in the area of the nucleus hypoglossus, the dorsal motor nucleus of nucleus vagus, nucleus ambiguus, nucleus facialis, nucleus abducens and motor nucleus of nucleus trigeminus. Additionally, labelled nuclei were found in the preganglionic sympathetic and preganglionic parasympathetic cells of the nucleus intermediolateralis and nucleus intercalatus in the spinal cord. In the medulla oblongata we found a cluster of cells with c-JUN-like immunoreactivity in an area between the dorsomedial part of the oral nucleus spinalis trigeminalis and the lateral border of the knee of facial nerve. Additionally, a second cluster of c-JUN-like immunoreactivity cells was visible between the ventromedial part of the oral nucleus spinalis trigeminalis and the lateral border of the rostral nucleus facialis. Examination of the characteristics of all cell groups with a basal c-JUN-like immunoreactivity in the spinal cord and lower brainstem revealed an overlapping distribution with cholinergic cell groups. Basal c-JUN-like immunoreactivity was also seen in the dorsal root ganglion cells. We examined the factors which can effect the expression of the c-JUN protein. Maximal expression of c-JUN-like immunoreactivity was observed after electrical stimulation of primary afferents. Stimulation of sciatic nerve at a strength sufficient to recruit A delta- and C-fibres produced c-JUN-like immunoreactivity in many nuclei of the ipsilateral dorsal horn of the lumbar spinal cord. c-JUN-like immunoreactivity was first detectable at 30 min following the end of stimulation, reached a maximum after 1 h, remained unchanged for another 1 h and declined to the basal level after 16 h. The distribution of c-JUN-like immunoreactivity in the lumbar cord coincided with the region of termination of sciatic nociceptive afferents. Contralateral c-JUN-like immunoreactivity appeared after 4 h. After noxious mechanical stimulation of the plantar hindpaw c-JUN-like immunoreactivity occurred in the spinal area of termination of nociceptive afferents of the tibial nerve. Noxious stimulation did not provoke additional c-JUN-like immunoreactivity in dorsal root ganglia.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
43.
Diagnostic utility of a multiplex herpesvirus PCR assay performed with cerebrospinal fluid from human immunodeficiency virus-infected patients with neurological disorders 总被引:2,自引:0,他引:2
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Quereda C Corral I Laguna F Valencia ME Tenorio A Echeverria JE Navas E Martín-Dávila P Moreno A Moreno V Gonzalez-Lahoz JM Arribas JR Guerrero A 《Journal of clinical microbiology》2000,38(8):3061-3067
We used a multiplex nested-PCR assay for the simultaneous detection in cerebrospinal fluid (CSF) of five human herpesviruses (HVs) (cytomegalovirus [CMV], Epstein-Barr virus [EBV], varicella-zoster virus [VZV], herpes simplex virus [HSV], and human herpesvirus 6 [HHV-6]) in a clinical evaluation of human immunodeficiency virus (HIV)-infected patients with neurological disorders. This method, which has the advantages of being rapid and economical, would be of particular interest for the diagnosis of neurological syndromes caused by more than one HV. We studied 251 CSF samples from 219 patients. HV DNA was demonstrated in 93 (37%) of the CSF samples (34% of the patients). CMV was the HV most frequently detected in our patients (25%), while EBV, VZV, HSV, and HHV-6 DNAs were present in significantly fewer cases (7, 4, 3, and 1%, respectively). When results were compared with the final etiological diagnoses of the patients, the multiplex HV PCR showed high specificity for the diagnosis of CMV and VZV neurological diseases and for cerebral lymphoma (0.95, 0.97, and 0.99, respectively). The sensitivity of the assay was high for CMV disease (0.87), was low for cerebral lymphoma (0.33), and was not evaluable for VZV disease due to the small number of patients with this diagnosis. Nevertheless, detection of VZV DNA had possible diagnostic value in four of the nine cases, and EBV DNA amplification always predicted the diagnosis of cerebral lymphoma in patients with cerebral masses. Detection of HSV DNA was frequently associated with CMV amplification and fatal encephalitis. HHV-6 was not considered to have a pathogenetic role in the three cases in which it was detected. This multiplex HV PCR assay is a specific and clinically useful method for the evaluation of HIV-infected patients with neurological disorders related to HV. 相似文献
44.
45.
Wendy Lo Thomas Bravo Vikram Jadhav Elena Titova John H. Zhang Jiping Tang 《Neuroscience letters》2007
Neurosurgical procedures can result in brain injury by various means including direct trauma, hemorrhage, retractor stretch, and electrocautery. This surgically-induced brain injury (SBI) can cause post-operative complications such as brain edema. By creating a mouse model of SBI, we tested whether NADPH oxidase, an important reactive oxygen species producing enzyme, is involved in SBI using transgenic mice lacking gp91phox subunit of NADPH oxidase (gp91phox KO) and apocynin, a specific inhibitor of NADPH oxidase. Neurological function and brain edema were evaluated at 24 h post-SBI in gp91phox KO and wild-type littermates grouped into SBI and sham-surgery groups. Alternatively, mice were grouped into vehicle- and apocynin-treated (5 mg/kg, i.p. 30 min before SBI) groups. Oxidative stress indicated by lipid peroxidation (LPO) was measured at 3 and 24 h post-SBI. The gp91phox KO mice, but not the apocynin-treated mice showed significantly improved neurological scores. Brain edema was observed in both gp91phox KO and wild-type groups after SBI; however, there was no significant difference between these two groups. Brain edema was also not affected by apocynin-pretreatment. LPO levels were significantly higher in SBI group in both gp91phox KO and wild-type groups as compared to sham group. A trend, although without statistical significance, was noted towards attenuation of LPO in the gp91phox KO animals as compared to wild-type group. LPO levels were significantly attenuated at 3 h post-SBI by apocynin-pretreatment but not at 24 h post-SBI. These results suggest that chronic and acute inhibition of NADPH oxidase activity does not reduce brain edema after SBI. Long-term inhibition of NADPH oxidase, however improves neurological functions after SBI. 相似文献
46.
I Bravo G S Carvalho M A Barbosa M de Sousa 《Journal of biomedical materials research》1990,24(8):1059-1068
In vitro studies were conducted to determine the effects of metal ions known to be released from metallic implants in vivo on the expression of lymphocyte surface antigens. Normal human peripheral blood lymphocytes were exposed to various concentrations of metal ions (Fe3+, Ni2+, Co2+, Mo6+, V5+, Cr6+, Cr3+, and Ti3+) for 30 min at 37 degrees C in a 5% CO2 atmosphere, and then analyzed for their ability to form rosettes with sheep red blood cells. Following this preliminary analysis, lymphocytes were exposed to the metal ions found to inhibit the E-rosette reaction (Fe3+, Ni2+, and Co2+) in order to determine which of the following surface antigens were affected: CD2, CD3, CD4, CD8, CD1, CD22, CD10, and HLA-DR. Our results showed that the in vitro treatment of lymphocytes with Fe3+ or Co2+ caused inhibition of CD2 only, whereas Ni2+ caused inhibition of both CD2 and CD3 antigens. These findings suggest that Fe3+, Co2+, and Ni2+ ions may interfere with T cell activation since both CD2 and CD3 are involved in that process. 相似文献
47.
Antiphospholipid antibodies and the outcome of pregnancy after the first in-vitro fertilization and embryo transfer cycle 总被引:1,自引:1,他引:1
Balasch J; Creus M; Fabregues F; Civico S; Reverter JC; Carmona F; Tassies D; Vanrell JA 《Human reproduction (Oxford, England)》1998,13(5):1180-1183
Increased antiphospholipid antibody prevalence has been demonstrated by a
number of recent studies in in-vitro fertilization (IVF) patients but the
potential effects of antiphospholipid antibodies on the different
components of the reproductive process and the consideration of whether to
test IVF patients for antiphospholipid antibodies are controversial. The
present study was undertaken to investigate the possible association
between the presence of circulating antiphospholipid antibodies (namely the
lupus anticoagulant and anticardiolipin antibodies), among a series of 21
consecutive IVF patients having a clinical spontaneous abortion after their
first embryo transfer. As a control group (n=42), the nearest IVF cycle
resulting in an ongoing pregnancy before and after each miscarried IVF
cycle (i.e. the closest cycles in temporal relationship to the index cycle)
was used. One patient (4.8%) in the study group and two women (4.8%) among
controls were seropositive for antiphospholipid antibodies. These low and
similar seropositivity rates found in the two groups studied lead us to
conclude that antiphospholipid antibodies testing in IVF patients should be
considered only in those women having repeated failures of
implantation/clinical abortion after embryo transfer but not in an
infertile general population reaching an IVF programme.
相似文献
48.
The effectiveness of a treatment protocol for male lower urinary tract symptoms in general practice: a practical randomised controlled trial
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Roelf JC Norg Kees van de Beek Piet JM Portegijs CP Onno van Schayck J Andr Knottnerus 《The British journal of general practice》2006,56(533):938-944
BACKGROUND: Randomised controlled trials have shown the efficacy of several treatment modalities for lower urinary tract symptoms (LUTS) in selected populations. The effectiveness in daily practice has hardly been investigated, especially in primary care and is dependent on choices between all possible treatment options and best investigated in a comprehensive study, including all treatment modalities (watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors, and surgery). AIM: Assessment of the effectiveness of a comprehensive treatment protocol for LUTS in primary care. DESIGN OF STUDY: Randomised controlled trial. SETTING: Fourteen general practices in the Netherlands. METHOD: Intervention: treatment protocol based on a formalised expert opinion. Control condition: usual care. Study population: 208 subjects with moderate to severe LUTS (IPSS > or =8, median = 13). OUTCOME MEASURES: symptom severity (IPSS [International Prostate Symptom Score]), bother score (Dan-PSS [Danish Prostate Symptom Score]), and maximum urinary flow (Q(max)); incidence of acute urinary retention and urinary tract infections. RESULTS: In the intervention group markedly more subjects used an alpha-blocker at end of follow-up than in the usual care group (24% versus 6%). No significant differences were found between intervention and control group in IPSS, Q(max) or Dan-PSS. CONCLUSION: alpha-blockers and watchful waiting are the most frequent treatment modalities for LUTS in primary care. Our study showed no evidence that a protocol using well-defined indications for all possible treatment modalities based on a formalised expert opinion procedure has added value. Based on our results, we cannot recommend a broadening of the indication for alpha-blockers, which, however, seems to be the current trend. 相似文献
49.
Clarke GN; Bourne H; Hill P; Johnston WI; Speirs A; McBain JC; Baker HW 《Human reproduction (Oxford, England)》1997,12(4):722-726
Donor insemination (DI) using cryopreserved semen commenced at The Royal
Women's Hospital in 1976. Over the next 15 years we performed 5953
treatment cycles to achieve 816 pregnancies (13.7% per cycle) and 706 live
births. In-vitro fertilization (IVF) using donor spermatozoa commenced in
1986. Over the next 5 years we performed 303 treatment cycles for 185
couples. Including subsequent transfer of cryopreserved embryos, a total of
33% of couples achieved a successful pregnancy by IVF. Statistical analysis
indicated that, for DI pregnancies, the most important semen variable was
the percentage post-thaw motility, whilst for normal fertilization in IVF
it was the pre-freeze motility. These results may be explained by the
compensatory effects of post-thaw processing of spermatozoa for IVF, but
not for DI in our clinic.
相似文献