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71.
72.
The effects of angiotensin II (ANG II) and natriuretic peptides (NPs) of the eel (ANP, atrial natriuretic peptide; CNP, C-type natriuretic peptide; and VNP, ventricular natriuretic peptide) on prolactin (PRL(188) and PRL(177)) and growth hormone (GH) release from the organ-cultured tilapia pituitary were examined. Eel ANG II at concentrations greater than 1 nM stimulated the release of PRL(188) and PRL(177) in a dose-related manner during the first hour of incubation. Significant stimulation by 100 nM ANG II on PRL(177) release was observed until 4h of incubation, and on PRL(188) release until 12 h. No effect of ANG II was seen on GH release. None of the NPs altered the release of PRLs at any time point. On the other hand, eel VNP at concentrations greater than 1 nM stimulated GH release in a dose-related manner after 4 h, and significant stimulation was observed until 48 h. Eel CNP was less effective than eel VNP; significant stimulation of GH release was observed at 1 and 10 nM during 24-48 h of incubation. No significant effect of eel ANP on GH release was seen at any concentration. ANG II had no effect on GH release at any time point. There was no change in mRNA levels of PRLs or GH in the pituitaries incubated with ANG II for 8 h or those incubated with the NPs for 48 h. These results indicate rapid and short-lasting stimulation by ANG II on PRL release and slow and long-lasting stimulation by VNP and CNP on GH release from the tilapia pituitary.  相似文献   
73.
BACKGROUND: Bartonella quintana, the etiological agent of bacillary angiomatosis (BA), causes endothelial cell proliferation. Erythromycin has dramatic effects on BA, and the effects are largely unexplained by the compound's bacteriostatic properties. Our aim here was to evaluate the possibility that erythromycin alters angiogenesis. METHODS: The effect of erythromycin on B. quintana-induced endothelial cell proliferation was studied using a wild-type strain and an erythromycin-resistant B. quintana mutant. The latter was generated by serial subcultures on blood agar plates. RESULTS: We show that erythromycin significantly inhibits the proliferation of dermal microvascular endothelial cells induced either by wild-type B. quintana or by our erythromycin-resistant mutant. Doxycycline and gentamycin failed to exert such an effect. Finally, we found that the resistant strain harbored a 27-bp insertion in the highly conserved region of the gene encoding the ribosomal protein L4; this insertion may explain the existence of the resistance to erythromycin. CONCLUSION: The data presented here indicate that erythromycin profoundly down-modulates endothelial cell proliferation irrespective of its bacteriostatic effects and suggest that this may be a key component of the efficacy of the compound in the treatment of patients with BA.  相似文献   
74.
In this report we describe a patient with Sjo¨gren’s syndrome (SS) and calcitriol-mediated hypercalcaemia. Initially, there was no clinical evidence of sarcoidosis. The patient had hypercalcaemia associated with increased calcitriol serum levels; circulating interleukin-6 and tumour necrosis factor alpha levels were also elevated. At the beginning, therapy with clodronate was effective in decreasing the serum calcium levels. However, the serum calcitriol decreased only after chloroquine treatment was added. After 2 years of therapy, the patient developed progressive and extensive muscle weakness. A muscle biopsy revealed a very prominent non-caseating granulomatous myopathy. Corticosteroid therapy was then instituted. Although both chloroquine and corticosteroid therapy were associated with decreased serum interleukin and calcitriol levels, only corticosteroid therapy was effective in treating the sarcoid myopathy. The role of cytokines in calcitriol mediated hypercalcaemia is discussed. Received: 1 February 1999 / Accepted: 2 June 1999  相似文献   
75.
76.
Following spinal transection of the upper thoracic spinal cord, male Sprague-Dawley rats given legshock whenever a hindlimb is extended learn to maintain the leg in a flexed position. The region of the cord that mediates this instrumental learning was isolated using neuroanatomical tracing, localized infusion of lidocaine, and surgical transections. DiI and Fluoro-Gold microinjection at the site of shock application labeled motor neuron bodies of lamina IX in the lower lumbar region. Local application of the Na-super++ channel blocker lidocaine disrupted learning when it was applied over a region extending from the lower lumbar (L3) to upper sacral (S2) cord. The drug had no effect rostral or caudal to this region. Surgical transections as low as L4 had no effect on learning. Learning also survived a dual transection at L4 and S3, but not L4 and S2. The results suggest that the essential neural circuit lies between L4 and S3.  相似文献   
77.
An accession of Vitis vinifera cv. Red Globe from Argentina, was found to be infected with Grapevine leafroll-associated virus-5 by ELISA. It was partially sequenced, and three ORFs, corresponding to HSP70h, HSP90h, and CP, were found. This isolate shares a high aminoacid identity with the previously reported sequence of the virus, and identities between 80% and 90% with previously reported GLRaV-9 and GLRaV-4 isolates. The analysis of the sequence supports the clustering together with GLRaV-4 and GLRV-9 inside the Ampelovirus genus.  相似文献   
78.

Introduction

Many women enrolled in the Spanish National Health Service also take out private health insurance to improve gynecological follow-up and complementary examinations, such as annual mammograms. We analyzed the cure rate of these patients when diagnosed with breast cancer and treated with surgery with curative intent.

Material and methods

Both overall survival and prognosis were analyzed in patients with breast cancer without metastases referred to a private oncology facility and treated with definitive surgery in the context of multidisciplinary treatment.

Results

Between 1994 and 2009, 395 patients with breast cancer were analyzed. Thirty-eight had metastases at diagnosis and 357 could be treated with definitive surgery: conservative in 265 patients and mastectomy in the remaining 92. The median follow-up was 64 months and the 5-year survival rate was 91%: 97% for stage I, 94% for stage II and 77% for stage III. In women diagnosed by mammography, the 5-year survival rate was 96% versus 86% for women consulting a gynecologist after self palpation or for other symptoms (p = 0.0159). Treatment was conservative in 74%, with better survival than in the remaining 26% who were treated with mastectomy (p = 0.0024). Survival was greater in patients with positive hormone receptors than in those with negative hormone receptors (p = 0.0264). Hormone receptor status was the only independent prognostic factor in multivariate Cox analysis.

Conclusions

Patients with breast cancer treated with definitive surgery in a private health insurance system have high cure rate, possibly because they are diagnosed in an early stage.  相似文献   
79.
The sciatic nerve (SN) is easily blocked under ultrasound guidance by identifying either the SN common trunk or its two components: the tibial nerve (TN) and the common peroneal nerve (CPN). The authors investigate whether there are anatomical differences between newborns and adults. The SN, TN and CPN of both lower extremities in 24 (11 neonatal and 13 adults) formolized cadavers were dissected. Distances were measured from the origin of the SN (passing under the piriformis muscle) to its division into TN and CPN, and from there to the popliteal crease. The sciatic/thigh coefficient (proportion relating SN length to thigh length) and the variation coefficient for the SN were calculated. The distance from the popliteal crease to the SN division was significantly shorter in neonates than in adults (1.04 ± 0.9 cm vs. 5.6 ± 5.1 cm, P = 0.0003). In addition, the neonatal SN divided at a proportionally more distal position in the thigh than it did in adults (86 ± 13 vs. 74 ± 15%, P = 0.0059). However, the coefficient of variation between the SN‐division distances was not statistically different in infants and adults (12.8 vs. 18.2%, P = 0.4345). The variations in the point of SN division seen in the adult SN are already seen in the neonatal period, but in newborns the SN divided in a more distal position in relation to the thigh than in adults, so this finding of anatomical variability in neonates suggests that ultrasound guidance can be useful when performing a SN block in these small patients.  相似文献   
80.
Sensitivity of cervical cytology is suboptimal, especially in developing countries such as Mexico, despite available guidelines aimed at improving this. When obtaining cervical samples, whether the samples are taken from the transformation zone and whether abnormal cells are missing must be considered. Cervical secretions (CS) are always present in variable proportions, and when cleaning the cervix, better samples may be obtained. In this study, we analyzed samples obtained with or without cleaning the cervix, and compared their contents in order to determine the sensitivity and specificity of these two methods. Methods: Of 500 patients who underwent cytology and colposcopy, 271 (54.2%) required a second opinion due to a diagnosis of cervical intraepithelial neoplasia (CIN). CS was removed and compared with the clean, second sample (SS) using in both liquid-based cytology. The quality of samples according to the Bethesda System, the presence of CIN, and inflammatory reactions were recorded. The sensitivity and specificity were calculated using biopsy as the gold standard. Results: The SS resulted in a higher proportion of adequate samples being obtained (97.6% vs. 44.8%), and in increased sensitivity (88.2% vs. 58.8%). CIN was detected in the SS 26% more often than in the CS (34 vs. 27 samples), whereas inflammatory reactions were noted more often in the CS (91.4% vs. 74%). Conclusion: Cervical sampling including CS results in lower sensitivity and CIN detection rates, and in more inflammatory reactions. By excluding CS from cervical samples, the sensitivity could be improved and the false negative rate could be reduced.  相似文献   
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