首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
This article reviews related studies from the authors' laboratory, which focus on the regulation of vascular Na+,K+-ATPase in hypertension. Earlier studies, including the authors', suggested that Na-pump activity in cardiovascular tissues is subject to regulation during hypertension; most of these studies report a stimulation of the vascular enzyme during established stages of hypertension. To test hypothesis that in vascular smooth muscle, strain resulting from elevated pressure may be a signal initiating a cascade of events leading to increased expression of Na+,K+-ATPase, the authors used cell culture and the Flexercell Strain Unit to apply cyclical stretch to rat aortic smooth muscle cells (ASMC) for several days. These studies demonstrated that mechanical strain induces the upregulation of both the alpha-1 and alpha-2 subunits of Na+,K+-ATPase. Mechanisms underlying these changes appear to involve a transient increase in intracellular sodium entering the cell through stretch-activated channels. Calcium entering the cell via L-type channels did not affect stretch-induced upregulation of the alpha isoforms. In addition, protein kinase C inhibition resulted in inhibition of the Na-pump during stretch, but not under nonstretch conditions. The authors conclude that the stretch component of vascular pressure upregulates the Na+,K+-ATPase catalytic subunits. Intracellular sodium may be a signal for this regulation. In addition, phosphorylation by PKC may be important in stretch-induced short-term regulation of the vascular Na-pump.  相似文献   

2.
3.
There has been considerable public concern that emissions from intensive livestock farming may have hazardous effects on human health, particularly on the respiratory system. From October 1991 to September 1992, data on consultations of asthmatic children (up to 8 years) were obtained by a network of 25 GP and paediatric practices in South Oldenburg, a region with one of the highest livestock densities in Germany. Comparable data from a similar network of 75 practices in 3 adjacent regions (Brunswick, Hanover, Verden) with average livestock density served as a reference. In South Oldenberg, 2084 consultations of 542 asthmatic children were observed, with asthma being the reason for visit in 734 of the contacts (36%). The boy-girl ratio was 2.1:1 among index patients and 1.9:1 among consultations. Consultation rate was 25.2 contacts by asthmatic children per 1,000 total consultations of children up to 8 years in South Oldenburg, compared to 17.8 per 1,000 in Hanover, 15.7 per 1,000 in Brunswick and 13.6 per 1,000 in Verden. Consultations due to asthma scored 11.2/1,000 in South Oldenburg, 10.8/1,000 in Hanover, 7.2/1,000 in Brunswick and 6.5/1,000 in Verden. Asthmatic patients in South Oldenburg were younger (mean age 38 vs. 42 months) than those observed in the reference regions. There were no regional patterns in sex ratio, severity of asthma, respiratory allergies or atopic dermatitis. As this is an ecological study design, inferences concerning the cause of the observed regional differences can only be weak. We therefore propose a case-control study in order to obtain exposure and health data on an individual level.  相似文献   

4.
We describe a female diabetic patient who presented with features suggestive of hepatobiliary disease and who exhibited clinical signs of fulminant hepatic failure. Identification and drainage of a right perinephric abscess resulted in prompt resolution of both the physical signs and biochemical indices of liver disease. Infection remote from the hepatobiliary tree can mimic fulminant hepatic failure, and recognition of this unusual presentation of infection is important if dangerous delay in diagnosis and treatment is to be avoided.  相似文献   

5.
Non-A, non-B or seronegative hepatitis is the leading indication for liver transplantation in patients with fulminant hepatic failure (FHF). We examined protocol annual review liver allograft biopsy specimens in consecutive adult patients transplanted for FHF in an attempt to determine the extent of the histological changes. One hundred eleven biopsy specimens from 41 patients transplanted for fulminant seronegative hepatitis and 34 from a comparison group of 16 patients transplanted for other causes of FHF (11 paracetamol overdose, 2 idiosyncratic drug reaction, 3 Wilson's disease) were available. Specimens were analyzed using standard proforma without knowledge of the original diagnosis. Chronic hepatitis was present in 29 patients (71%) transplanted for fulminant seronegative hepatitis (23 mild, 3 moderate, and 3 severe) compared with 5 patients (31%, all mild) transplanted for other causes of FHF. Twenty-five patients (61%) grafted for seronegative FHF had fibrosis (13 mild, 9 moderate, and 3 severe) in contrast to 4 fibrosis (25%) (all mild) in the comparison group. Excluding early allograft failure because of primary graft nonfunction or vascular complications, six patients with seronegative FHF required retransplantation (2 = chronic rejection; 1 = severe hepatitis with panacinar necrosis, resembling original liver; and 3 = chronic hepatitis with precirrhotic fibrosis and prominent cholestasis of unknown cause). One patient in the comparison group had a second graft (chronic rejection). Posttransplantation chronic hepatitis is more frequent and severe in patients transplanted for seronegative hepatitis. Graft survival may be adversely influenced by the development of chronic hepatitis, which may represent persistent or recurrent disease.  相似文献   

6.
7.
8.
BACKGROUND: Small-bowel transplantation is an alternative to home parenteral nutrition (HPN) in patients with gut failure. Our aim was to report the indication, diagnosis, morbidity, mortality, and intestinal adaptation in the total cohort of Danish patients receiving HPN at any time during the 5 years between 1 January 1991 and 31 December 1995. The data were analysed against the option of transplantation. RESULTS: HPN was given to 129 patients; 59 (46%) had inflammatory bowel disease (15% died), 26 (20%) had cured cancers (42% died), and 44 (34%) had other diseases (dysmotility, surgical complications, infarcts, and so forth; 27% died). Of these, 60% were new in the HPN program, but only 19% received HPN all 5 years; 31 % had terminated HPN, 19% permanently, and 25% died. Only four deaths were HPN-related. In December 1995, 73 patients were receiving HPN in Denmark, for a prevalence of 13.9 per million, which is the highest in Europe but 10-fold lower than in the United States. CONCLUSIONS: Gut failure was the only indication for HPN in Denmark. Weight loss without gut failure, such as disseminated cancer and acquired immunodeficiency syndrome, was not an indication for HPN. Survival after small-bowel transplantation should be assessed against a sizeable mortality among candidates receiving HPN, and this depends on diagnosis and age. In an HPN population comparable with the Danish, a quarter is likely to die within a period of 5 years, a quarter will terminate HPN, and the others survive with HPN. Small-bowel transplantation can be a lifesaving procedure in the small fraction of foreseeable HPN-related deaths, mainly caused by liver failure. Transplantation will not improve survival in most adult HPN patients, and only an improved quality of life after transplantation justifies this procedure in most HPN patients.  相似文献   

9.
We studied 32 patients with the thickened lesions of the wall of the gallbladder by using dynamic MRI. We tried the differential diagnosis of gallbladder lesions according to the time intensity curve (TIC) and enhanced pattern. TIC of carcinoma was elevated more seeply from plain to arterial phase than the inflammatory diseases. The Inflammatory diseases were keeping three-layer structures of the wall of the gallbladder, but gallbladder carcinoma destroys the wall-structure. We could diagnose as direct liver invasion of the carcinoma clearly. We could exactly diagnose adenomyomatosis in dynamic MRI by small low intensity spots within the wall of the gallbladder. In the patients with gall stones, the wall of the gallbladder were more clearly observed in dynamic MRI compared with US and EUS.  相似文献   

10.
11.
Levels of clotting factors II, V, and VII were measured on admission and then daily in 12 patients with grade IV hepatic coma due to fulminant hepatic failure. Factor VII levels obtained within 36 hours of the development of grade IV coma were not of value in predicting which patients would subsequently recover consciousness. Four of the latter group had levels below 9% at this time while the levels in three of the seven fatal cases were higher. Serial determinations were of more value and levels rose rapidly in those patients who ultimately made a complete recovery.  相似文献   

12.
In vivo, endothelial cells (ECs) are subjected to a complex mechanical environment composed of shear stress, pressure, and circumferential stretch. The aim of this study was to subject bovine aortic ECs to a pulsatile pressure oscillating from 70 to 130 mm Hg (mean of 100 mm Hg) in combination with pulsatile shear stresses from 0.1 to 6 dyne/cm2 (1 dyne/cm2=0.1 N/m2) with or without a cyclic circumferential stretch of 4% for 1, 4, and 24 hours. The effect of highly reversing oscillatory shear stress (range -3 to +3 dyne/cm2, mean of 0.3 dyne/cm2) typical of regions prone to the development of atherosclerotic plaques was also studied at 4 and 24 hours. Endothelin-1 (ET-1) and endothelial constitutive nitric oxide synthase (ecNOS) mRNA expression was time and mechanical force dependent. ET-1 mRNA was maximal at 4 hours and decreased to less than static culture expression at 24 hours, whereas ecNOS mRNA increased over time. Pressure combined with low shear stress upregulated ET-1 and ecNOS mRNA compared with static control. Additional increase in expression for both genes was observed under a combination of higher shear stress and pressure. A cyclic circumferential stretch of 4% did not induce a further increase in ET-1 and ecNOS mRNA at either low or high shear stress. Oscillatory shear stress with pressure induced a higher expression of ET-1 mRNA but lower expression of ecNOS mRNA compared with unidirectional shear stress and pressure. We have shown that the combination of pressure and oscillatory shear stress can downregulate ecNOS levels, as well as upregulate transient expression of ET-1, compared with unidirectional shear stress. These results provide a new insight into the exact role of mechanical forces in endothelial dysfunction in regions prone to the development of atherosclerosis.  相似文献   

13.
OBJECTIVE: To evaluate the association between admission serum concentrations of the actin-scavenger, Gc-globulin, and the subsequent development of multiple organ failure in patients with fulminant hepatic failure. DESIGN: Retrospective study. SETTING: A hepatologic intensive care unit. PATIENTS: Seventy-nine patients with hepatic encephalopathy grade 3 or 4. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Serum admission concentrations of both total and nonactin-complexed (free) Gc-globulin were determined. The development of cardiovascular failure, renal failure, pulmonary failure, intracranial hypertension, and infections were recorded in each patient. Both total and free Gc-globulin values were significantly lower in the patients, compared with normal controls. The Gc-globulin values were significantly reduced in patients who subsequently developed cardiovascular failure (p < .01), intracranial hypertension (p < .001), and infections (p < .001), compared with those patients who did not. No differences were found between patients with and without pulmonary or renal failure. Patients with total Gc-globulin values in the lowest quintile had on average 2.6 organ failures, whereas patients with Gc-globulin concentrations in the highest quintile had 0.9 organ failures. The corresponding figures for the lowest and highest quintiles of free Gc-globulin were 3.0 and 1.1 organ failures, respectively. Both total and free Gc-globulin were inversely correlated to the number of organ failures (p < .005 in both cases). Patients with multiple organ failure (> or = 2 organ failures) had significantly reduced Gc-globulin values compared with patients without multiple organ failure (p < .0001). CONCLUSIONS: In patients with fulminant hepatic failure, the lowest admission Gc-globulin concentrations were associated with the subsequent development of cardiovascular failure, intracranial hypertension, and infections. Lack of Gc-globulin correlated significantly with the development of multiple organ failure and may be pathogenetically involved in this condition.  相似文献   

14.
The role of hepatitis C virus (HCV) infection in fulminant hepatic failure is controversial. The frequency of serum HCV RNA positivity in previously reported patients with fulminant hepatic failure (FHF) of indeterminate cause ranged from 0 to 12% in the United States and Europe and from 43% to 59% in Asia. We assessed serum HCV RNA using polymerase chain reaction (PCR) and oligoprimers from the 5'UTR of the HCV genome in 26 consecutive patients with FHF. Another laboratory independently performed PCR on 21 of the serum samples using different oligoprimers from the 5'UTR and NS3 region of the HCV genome. Serum HCV RNA was detected in two of seven (28%) patients with hepatitis B, 9 of 15 (60%) with an indeterminate cause, and in none with hepatitis A (n = 2) or drug-induced hepatotoxicity (n = 2). HCV RNA PCR results were concordant between both laboratories in 17 of 21 (81%) of samples. In patients with an indeterminate cause, HCV RNA positivity was significantly associated with the transmission risk factor of low socioeconomic status and Hispanic ethnicity. Eighteen patients underwent liver transplantation (LT) and 15 (83%) survived. Among patients with FHF of indeterminate cause, recurrent or acquired HCV infection after transplantation occurred in three of five (60%) and one of four (25%) patients, respectively. Three of four (75%) patients with hepatitis C virus infection post-LT also developed histologic hepatitis. HCV appears to be the causative agent of a substantial number of cases of FHF classified as indeterminate in the Los Angeles area. Differences in patient populations or risk factors may explain the discordant incidences of HCV infection in FHF observed among different programs.  相似文献   

15.
A program for early mobilization in the hospital and rehabilitation at home after hip fracture was developed in cooperation with local health and social authorities and applied to 103 consecutive patients having a mean age of 75 years. All were admitted to the hospital from their own homes. Three fourths of the patients returned home directly after postoperative mobilization periods of usually two to three weeks in hospital. Four months after the fracture 81 of 99 surviving patients were at home, most of them having regained their prefracture functional status. One year after the fracture 91 patients were alive, and 78 of these were at home with no functional loss, compared with their condition at four months. Some of the social and medical factors which may already be pertinent to the recovery outcome at the time of fracture are identified. Eight to nine of ten patients with two or three positive factors ("healthy," living with someone, and ability to walk two weeks postsurgery) returned directly home. This study suggests the importance of intensive support, in the form of information to patients and relatives, and close cooperation between hospital staff and community care authorities. By this means, a continuity of care and early permanent independence can be achieved for elderly hip fracture patients and institutionalized rehabilitation can be reduced with benefit for both the individual and society.  相似文献   

16.
17.
Recently, we reported that ciprofloxacin, an antimicrobial agent with gamma-aminobutyric acid (GABA(A)) receptor antagonist properties, significantly increases hepatic regenerative activity in animal models of alcohol-induced liver disease and cirrhosis. In the present study, we documented the effects of ciprofloxacin on survival and hepatic regeneration in a D-galactosamine (D-gal)-induced model of acute hepatic injury in rats. One hundred nineteen adult, male Sprague-Dawley rats (n = 19-20/group) were treated with intraperitoneal D-gal (total dose: 2.5 g/kg), followed by gastric gavage with either saline, ciprofloxacin (10, 50, or 100 mg/kg), norfloxacin (250 mg/kg), or intraperitoneal putrescine (300 micromol/kg), a potent hepatic growth promoter. Mortality rates were then documented over a 4-day period. An additional 45 rats (n = 15/group) received a sublethal dose of D-gal (1.0 g/kg), followed by gastric gavage with either saline or ciprofloxacin (100 mg/kg), or intraperitoneal putrescine (300 micromol/kg). In these rats, hepatic regenerative activity was documented at 12, 24, and 60 hours post-D-gal by 3H-thymidine incorporation into hepatic DNA and proliferating cell nuclear antigen (PCNA) staining. In the survival study, a dose-response effect of ciprofloxacin on survival was observed (ciprofloxacin: 10 mg/kg, 10%; 50 mg/kg, 26%; and 100 mg/kg, 35%) with the results in the 100-mg/kg-treated group being significant when compared with the 5% survival rate in saline-treated controls (P < .05). Survival figures in the norfloxacin- and putrescine-treated groups were not significantly improved (15% and 25%, respectively). In the regeneration study, compared with the D-gal + saline-treated control group, DNA synthesis rates at 60 hours were increased in the D-gal + ciprofloxacin and D-gal + putrescine groups (10.2 +/- 3.3 vs. 18.2 +/- 5.1 and 18.8 +/- 6.8 x 10(3) dpm/mg DNA respectively; P < .05). The results of PCNA staining also supported enhanced hepatic regeneration in the ciprofloxacin-treated group at 60 hours (saline, 13.4 +/- 3.7; ciprofloxacin, 47.4 +/- 7.3; and putrescine, 8.4% +/- 2.8% hepatocytes staining positive). Ciprofloxacin at a dose of 100 mg/kg significantly improves survival and hepatic regenerative activity in this animal model of acute hepatic injury.  相似文献   

18.
19.
The kinetics of intravenously injected [14C]cholic acid have been investigated in 14 patients with fulminant hepatic failure, 24 to 36 hr after the development of grade IV encephalopathy. Radioactivity was measured in plasma samples and in the individual plasma bile acid fractions after separation by thin layer chromatography. Plasma disappearance curves of the free [14C]cholic acid were calculated by an iterative nonlinear least squares fitting procedure using a computer. The disappearance of total plasma radioactivity was similar in all patients and greatly prolonged compared with healthy subjects. However, the plasma disappearance of free [14C]cholic acid was significantly faster in the 8 patients who recovered consciousness than in the 6 who did not. Plasma disappearance of free [14C]cholic acid correlated highly significantly with the proportion of conjugated [14C]cholate in plasma. All patients in whom more than 70% of plasma radioactivity was in the conjugated fraction 3 hr after injection survived and left hospital, whereas all of those in whom less than 55% was conjugated died. Measuring the percentage conjugation of [14C]cholate 3 hr after injection may therefore be a useful test of residual liver function in hepatic failure, as a guide to prognosis and in evaluating new forms of treatment.  相似文献   

20.
Performed principal-component factor analyses on patient input (demographic and pretherapy expectations), therapist input (demographic), and patient perspective therapy process variables that significantly differentiated 71 early dropout from 110 nondropout outpatients at 2 community mental health centers. At 1 setting results confirm (a) the presence of selection factors in the intake process whereby the more disturbed patients, who subsequently drop out, are assigned to lower level trained therapists and (b) the proposition that many patients unilaterally terminate despite the perception of the initial session as being an overall positive experience. Findings at the 2nd setting support the more traditionally held view of "dropout" as related to patient dissatisfaction with received services. Differences in the dropout process at the 2 settings were attributed to empirically demonstrated differences in the therapists' theoretical approach to the initial interview. The proclivity of earlier investigators to conceptualize dropouts as being characteristic of a single type of patient seems to be another unfounded homogeneity myth. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号