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1.
1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non‐adrenergic non‐cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients’ quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence. 相似文献
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5.
Cholecystokinin-decreased food intake in rhesus monkeys 总被引:1,自引:0,他引:1
6.
This study analyses the influence of female and male patient age and human
menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and
live birth rates with ovulation stimulation using HMG in combination with
intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI
treatment cycles in 184 patients carried out at a university fertility
centre were analysed in a retrospective fashion. The main outcomes measured
were clinical pregnancy rates and live birth rates. Increased female
partner age (> or = 35) and male partner age (> or = 40) were found
to negatively influence pregnancy rates with HMG/ IUI therapy. In addition,
this study demonstrated a critical threshold of HMG requirements beyond
which pregnancy did not occur. No pregnancies occurred in treatment cycles
requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular
maturity, irrespective of patient age. In conclusion, female partner age,
male partner age, and HMG requirements all significantly influence
pregnancy rates with HMG/IUI therapy.
相似文献
7.
We report that very late antigen-1 (VLA-1(+)) CD3(+)CD45RO(+) T-cells are selectively segregated from VLA-1(-) peripheral blood (PB) mononuclear cells (MC), in which CD3(+) T-cells are evenly CD45RO(+) and CD45RO(-), when PBMC are stained with a monoclonal antibody (mAb) to VLA-1 and passaged on immunomagnetic columns. In contrast, both VLA-1(+) and VLA-1(-) MC isolated from synovial fluid (SF) are mainly CD45RO(+)CD3(+) T-cells. VLA-1(+) MC formed 13 +/- 5.3% of MC eluting from columns loaded with PBMC of patients with seropositive rheumatoid arthritis (n = 6) and 2.3 +/- 1.6% of patients (n = 4) with other arthritides (P < 0.022). Importantly, only the VLA-1(+) MC from PB and SF adhered to collagen IV upon triggering with phorbol 12-myristate 13-acetate. Moreover, adhesion and migration on collagen IV were preferentially maintained in lines cultured from VLA-1(+) T-cells, and both were inhibited by mAb to the VLA-1 alpha1 I domain. These results suggest that VLA-1(+) CD45RO(+) T-cells in patients with arthritis could play a role in both systemic and local inflammation by rapidly adhering to collagen IV. 相似文献
8.
Adrenergic mechanisms in cerebral circulation of the goat 总被引:1,自引:0,他引:1
9.
Szabolcs MJ Cannon PJ Thienel U Chen R Michler RE Chess L Yellin MJ 《Virchows Archiv : an international journal of pathology》2000,437(2):149-159
T cells have roles in the pathogenesis of native coronary atherosclerosis (CA) and transplant-associated coronary artery disease
(TCAD). The mechanisms by which T cells interact with other cells in these lesions are not fully known. CD154 is an activation-induced
CD4+ T cell surface molecule that interacts with CD40+ target cells, including macrophages and endothelial cells, and induces the production of pro-inflammatory molecules, including
CD54 (ICAM-1) and CD106 (VCAM-1). To investigate whether CD154-CD40 interactions might be involved in the pathogenesis of
CA or TCAD we performed immunohistochemical studies of CD154 and CD40 expression on frozen sections of coronary arteries obtained
from cardiac allograft recipients with CA (n=10) or TCAD (n=9). Utilizing four different anti-CD154 mAb we found that CD154 expression was restricted to infiltrating lymphocytes in
CA and TCAD. CD40 expression was markedly up-regulated on intimal endothelial cells, foam cells, macrophages and smooth muscle
cells in both diseases. Dual immunolabeling demonstrated many CD40+ cells co-expressed CD54 and CD106. The extent of CD40, CD54 and CD106 expression showed statistical significant correlation
with the severity of disease and the amount of intimal lymphocytes. Together these studies demonstrate the presence of activated
CD154+ and CD40+ cells in both CA and TCAD lesions and suggest that CD154-mediated interactions with CD40+ macrophages, foam cells, smooth muscle cells and/or endothelial cells may contribute to the pathogenesis of these diseases.
Received: 17 December 1999 / Accepted: 20 January 2000 相似文献
10.
Paramagnetic macrocyclic chelates show promise as magnetic resonance (MR) imaging contrast agents due to stability and relaxivity comparable to those of DTPA-type chelates. For the three copper and manganese macrocyclic complexes studied in aqueous solution, T1 and T2 relaxivities ranged from 0.14 to 5.88 mM-1sec-1 at 6.25 MHz. In rats, the intravenous administration of 16 mumol/kg of Mn(cyclam) caused the liver T1 relaxation rate to double at 15 minutes after injection. T1 measurements by pulsed MR imaging and manganese analyses on excised tissue showed that both relaxation rate (1/T1) and manganese content of liver and kidney increase linearly with the dosage of Mn(cyclam). The linear relationship between 1/T1 and manganese content can be considered an "in tissue" relaxivity plot for the agent. The resulting relaxivity is 54 mM-1sec-1 in liver, compared with 3.1 mM-1sec-1 in aqueous solution. Although this work is preliminary, the implication for medical MR imaging applications is that macrocyclic contrast agents can be effective at approximately one-tenth the current typical dose used for gadolinium DTPA. 相似文献