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101.
Meola SM Sittertz-Bhatkar H Pendleton MW Meola RW Knight WP Olson J 《Journal of molecular neuroscience : MN》2000,14(1-2):17-25
An antiserum raised against the peptide, culetachykinin II, immunocytochemically detected a group of neurosecretory cells
in the first flagellar segment of the antennae of both males and females of the mosquito, Culex salinarius. This is the first insect species in which neurosecretory cells have been found in the antennae. The ultrastructure of these
antennal neurosecretory cells (ANC) is described, as well as their relationship to other neurons in the antennae and antennal
lobe of the mosquito. These tachykinin-reactive cells contain relatively small (140–220 nm) elementary neurosecretory granules.
Not only do the ANC have axons that terminate on specific glomeruli of the deutocerebrum, but these neurons also have collaterals
that form neurohemal terminals in the receptor lymph channels of the dendrites of the sensory neurons. Thus, the ANC not only
influence higher centers of the brain that interpret signals from the antennal sensillae, but also modulate the response of
the sensory receptors. To our knowledge, this is the first report of neurosecretory cells directly affecting the signal reception
of sensory neurons. 相似文献
102.
Serum lipids in early pregnancy and risk of pre-eclampsia 总被引:1,自引:0,他引:1
Helga J. van den Elzen Researcher† Juriy W. Wladimiroff Professor Titia E. Cohen-Overbeek Researcher Anton J. de Bruijn Epidemiologist† Diederick E. Grobbee Professor † 《BJOG : an international journal of obstetrics and gynaecology》1996,103(2):117-122
Objective To determine whether first and late second trimester serum total and high density lipoprotein cholesterol are associated with blood pressure, uterine artery pulsatility index and pregnancy outcome.
Design A prospective cohort study. Data were analysed using multiple linear and logistic regression analysis.
Participants Three hundred and ninety-three pregnant women requesting chorionic villus sampling because of advanced maternal age (36 years and older).
Main outcome measures Serum total cholesterol and high density lipoprotein cholesterol were measured by an automated enzymatic method. Uterine artery flow velocity waveforms were recorded using continuous Doppler ultrasound. Pregnancy outcome was assessed by questionnaire.
Results First trimester serum total cholesterol was significantly associated with the risk of pre-eclampsia, with the adjusted relative risk exceeding 5 for women with serum total cholesterol levels above 6.0 mmol/l when compared with women with a cholesterol level below 5.0 mmol/l. First trimester serum total cholesterol also showed a significant relationship with diastolic blood pressure (coefficient of linear regression = 0.02 (mmol/l)/mmHg, 95% CI = 0.01 to 0.03), and the change in both diastolic and systolic blood pressure from the first to the late second trimester was associated with linear changes in serum total cholesterol and high density lipoprotein cholesterol.
Conclusions These data suggest a relation between serum lipids in early pregnancy and the development of pre-eclampsia. 相似文献
Design A prospective cohort study. Data were analysed using multiple linear and logistic regression analysis.
Participants Three hundred and ninety-three pregnant women requesting chorionic villus sampling because of advanced maternal age (36 years and older).
Main outcome measures Serum total cholesterol and high density lipoprotein cholesterol were measured by an automated enzymatic method. Uterine artery flow velocity waveforms were recorded using continuous Doppler ultrasound. Pregnancy outcome was assessed by questionnaire.
Results First trimester serum total cholesterol was significantly associated with the risk of pre-eclampsia, with the adjusted relative risk exceeding 5 for women with serum total cholesterol levels above 6.0 mmol/l when compared with women with a cholesterol level below 5.0 mmol/l. First trimester serum total cholesterol also showed a significant relationship with diastolic blood pressure (coefficient of linear regression = 0.02 (mmol/l)/mmHg, 95% CI = 0.01 to 0.03), and the change in both diastolic and systolic blood pressure from the first to the late second trimester was associated with linear changes in serum total cholesterol and high density lipoprotein cholesterol.
Conclusions These data suggest a relation between serum lipids in early pregnancy and the development of pre-eclampsia. 相似文献
103.
Wolfgang Hadnagy Gabriele Leng Dorothee Sugiri Ulrich Ranft Helga Idel 《International journal of hygiene and environmental health》2003,206(2):93-102
A multiparametric analysis of immune components was performed in blood and serum of 61 voluntary persons before and after (1 day, 3 days, 4-6 months, 10-12 months) a professional pest control operation (PCO) using pyrethroids. Following parameters were included in the study (1) immunological parameters of the humoral defence, i.e. immunoglobulins of the classes A, G, M and E, complement components C3c and C4, acute phase proteins such as acid alpha 1-glycoprotein, haptoglobin, C-reactive protein; (2) mediators and receptors of immunity, i.e. neopterin, soluble interleukin-2 receptor (sIL-2R), soluble interleukin-6 receptor (sIL-6R), soluble tumor necrosis factor receptor (sTNF RII); (3) immunological markers of the cellular defence, i.e. white blood cell counts and lymphocyte (sub)populations such as total lymphocytes (CD2), mature lymphocytes (CD3), T-helper/inducer cells (CD4), T-suppressor/cytotoxic cells (CD8), B-cells (CD20), natural killer cells (CD56), as well as the ratio of CD4/CD8. The medians of all investigated immune components found before and for all time intervals after pyrethroid application were within the reference interval with respect to the total collective. Within this physiological range the investigated parameters showed a trend to lower values predominantly during the early phase (1 and 3 days) after PCO, partially being significant. Significant decreases were no more present in the late phase (6 to 12 month) after PCO indicating reversibility. Atopics did not differ in the immune response after PCO as compared to non-atopics. Obtained results suggest a modulation of immune components after a correct performed PCO within the physiological range towards lower values during the first days. However these immune changes are considered to be subtle and underlying compensatory mechanisms of immunoregulation. 相似文献
104.
105.
106.
Gambacorta MA Manfrida S D'Agostino G Digesù C D'Onofrio I Rosato H Valentini V 《Rays》2005,30(2):181-187
Based on the successful results achieved in survival and local control with radiotherapy of prostate cancer recent studies tried to establish some models to reliably predict late rectal toxicity. In fact, the rectum, due to its location, represents an organ at risk of acute and late toxicity with the onset of acute or chronic radiation proctitis. The concept of late consequential effect has gained ground. It implies that the late damage might be a direct consequence of the acute damage. Dose-escalation studies, conformal radiotherapy (3D-CRT) and intensity modulated radiotherapy (IMRT) led to the identification of parameters, based on dose-volume histograms (DVH), able to separate patients at low and high risk of toxicity. Precise predictive dosimetric factors play a major role in the definition of the onset of toxicity. The monitoring system of late toxicity used by the authors is presented. 相似文献
107.
108.
Anatomical radical retropubic prostatectomy: 'curtain dissection' of the neurovascular bundle 总被引:5,自引:0,他引:5
OBJECTIVE: To investigate the topographical relationship of the cavernosal nerves (CNs) to seminal vesicles, prostate, rhabdosphincter and urethra during the development of the prostate, and to use the resulting morphological data to modify the surgical technique of nerve-sparing radical prostatectomy. MATERIALS AND METHODS: The study included 29 male fetuses (gestational age 9-37 weeks) and eight adult specimens assessed anatomically and histologically. Using the plastination technique and anatomical dissection, the course of the CNs was investigated in all specimens. Based on these morphological results, the technique of dissecting the CNs during nerve-sparing radical retropubic prostatectomy was modified. RESULTS: During early fetal development the fibres of the CNs enclose the prostatic and membranous urethra dorsally and laterally. During the growth of the prostate, the CNs running along the prostate become displaced further anteriorly and spread, thus forming a concave shape (like a 'curtain') of the neurovascular bundles (NVB). Therefore, dissection of the NVB has to start anteriorly to preserve all the nerve fibres that are spread along the surface of the lateral lobes of the prostate. CONCLUSIONS: From these anatomical findings we propose a modified 'curtain dissection' to improve preservation of the CNs running in the NVB, in which the incision of the periprostatic fascia and dissection of the NVB is far more anterior than previously described. 相似文献
109.
Zanow J Kruger U Petzold M Petzold K Miller H Scholz H 《Journal of vascular surgery》2005,41(6):913-1012
OBJECTIVES: In this report we present a novel procedure that uses an arterioarterial prosthetic loop (AAPL) with the proximal axillary or the femoral artery as a vascular access for hemodialysis in patients who have inadequate vascular conditions for creating an arteriovenous fistula or graft. METHODS: Between April 1996 and September 2004, 34 patients received 36 AAPLs as vascular access, either as an axillary chest loop (n = 31) or as a femoral loop (n = 5). In this procedure the artery is ligated between the anastomoses to direct flow through the AAPL. Data from all patients undergoing the procedure were prospectively collected. RESULTS: The indication for an AAPL was the unsuitability of large deep veins in 64%, steal syndrome in 11%, the combination of only a suitable femoral vein and severe peripheral arterial disease in 22%, and congestive heart failure in 3%. All AAPLs were cannulated 18 +/- 4 days postoperatively. Mean follow-up was 31 months (range, 1 to 83). Primary patency was 73% and secondary patency was 96% at 1 year; these rates at 3 years were 54% and 87%, respectively. The rate of all interventions for the maintenance of AAPL function was 0.47 procedures per patient year. Four grafts were abandoned. More than 11,000 hemodialyses with proven efficiency were performed. CONCLUSIONS: The AAPL is an unusual but useful and easy-to-perform alternative procedure to create vascular access for hemodialysis. It can provide survival for strictly selected patients in whom conventional vascular access is not possible. The axillary chest AAPL is preferred. 相似文献
110.
Brevik A Vollset SE Tell GS Refsum H Ueland PM Loeken EB Drevon CA Andersen LF 《The American journal of clinical nutrition》2005,81(2):434-439
BACKGROUND: Nutritional biomarkers may be used to assess dietary exposure without the errors commonly associated with self-reported dietary data. OBJECTIVE: The objective was to examine the association between plasma folate and intake of folate, fruit, and vegetables in a large cohort of healthy adults consuming foods that had not been fortified with folic acid. DESIGN: The present study population included 5533 middle-aged (47-49 y) and old (71-74 y) subjects from the Hordaland Homocysteine Study. The participants completed a food-frequency questionnaire and provided blood samples for chemical analyses. RESULTS: We observed a significant difference in plasma concentrations of folate across increasing quartiles of fruit, vegetable, and orange juice consumption. The difference in plasma folate between the highest and lowest quartiles was 1.97 (95% CI: 1.86, 2.07) nmol/L for fruit intake, 1.79 (95% CI: 1.69, 1.89) nmol/L for vegetable intake, and 2.69 (95% CI: 2.51, 2.87) nmol/L for orange juice intake. A significant inverse relation was observed across increasing quartiles of milk and bread intakes. The difference between the highest and lowest quartiles was -1.03 (95% CI: -1.13, -0.92) nmol/L for milk and -1.60 (95% CI: -1.69, -1.50) nmol/L for bread. CONCLUSION: Plasma folate concentration may be a useful biomarker for the intake of fruit and vegetables in populations consuming unfortified food products. The association can be attenuated by and should be corrected for individual intake of folic acid supplements. 相似文献