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71.
Society stress and peptic ulcer perforation   总被引:1,自引:0,他引:1  
To examine the relationship between society stress and peptic ulcer perforation, time-trend analysis was performed on the annual incidence of perforated peptic ulcer per 100 000 population in Hong Kong during the years 1962–85, when Hong Kong, as a developing city, went through significant socio-economic and political changes, and the trend was correlated with specially designed and validated society stress scores estimated annually during the same period. The society stress scores were derived independently by two expert panels blinded to the purpose of the study, one selecting and categorizing negative news events for Hong Kong during this period, and the other weighing the categories and scoring the impact of the news on Hong Kong. The incidence of perforation increased significantly during the years and manifested three distinct peaks, which coincided with the worst economic recession in Hong Kong, the influx of mainlander Chinese and Vietnamese boat people, and the Sino-British negotiation on the sovereignty of Hong Kong after 1997. Both linear and autoregression analysis, the latter taking into consideration point fluctuations in rates, showed that perforation rates correlated significantly with the society stress scores (r= 0.57, P < 0.002). The peak effects and the significant correlations indicate that an association exists between society stress and peptic ulcer perforation, and suggest that chronic society stress plays an important role in the aetiology of this condition, although the relatively low r value also suggests the presence of other aetiological factors.  相似文献   
72.
The purpose of the present study was to assess the agreement between measurements of baroreflex sensitivity (BRS) obtained by the Valsalva manoeuvre and by the phenylephrine test in patients with previous myocardial infarction and different degrees of left ventricular dysfunction. Patients with a previous myocardial infarction were enrolled consecutively into two groups according to their left ventricular ejection fraction (LVEF): 40% (n=52). All patients underwent BRS assessment by the phenylephrine technique (Phe-BRS) and by the Valsalva manoeuvre, with the latter using both the overshoot part of phase IV (Ov-VM-BRS) and the whole of phase IV (IV-VM-BRS). The linear association between methods was assessed by correlation analysis and the agreement was evaluated by computing the bias and the limits of agreement. IV-VM-BRS and Ov-VM-BRS could not be computed in 26% and 39% of patients respectively. For both indices a much higher percentage of non-computable Valsalva manoeuvre slopes was found in the group of patients with LVEF 40% the results were: r=0.91 (P<0.001), bias=0.1 ms/mmHg (P=0.84) and limits of agreement from -4.8 to 5 ms/mmHg. When comparing Phe-BRS and IV-VM-BRS, we found r=0.67 (P=0.001), bias=-1.5 ms/mmHg (P=0.06) and limits of agreement from -8.8 to 5.7 ms/mmHg in the group of patients with LVEF 40%. Dichotomizing Ov-VM-BRS, the best cut-off value to identify patients with a Phe-BRS of <3 ms/mmHg was found to be 7 ms/mmHg, giving 100% sensitivity and 69% specificity. In conclusion, estimation of BRS by the Valsalva manoeuvre in post-myocardial infarction patients is limited by a large number of non-measurable results. When computable, measurements are well correlated with those obtained by Phe-BRS, but, because of large limits of agreement, the two methods cannot be used interchangeably. If used as a screening test for risk stratification, the Valsalva manoeuvre could reduce by about one-third the need for phenylephrine injection.  相似文献   
73.
The aim of this study was to test whether prolonged administration of granulocyte colony-stimulating factor (G-CSF) would allow the collection by leukapheresis of PBHP in patients with SAA. For this purpose, nine SAA patients, 7 to 46 years old, six of whom were enrolled at diagnosis of their disease and three after previous immunosuppression had failed, were treated with antilymphocyte globulin (ALG) (day 1 to 5), cyclosporin A (5 mg/kg/d orally) (day 6 to 90) and G-CSF 5 micrograms/kg/d (day 6 to 90). A total of 40 leukaphereses were performed, (range 2 to 7 per patient), between days +10 and +168 from G- CSF treatment. White blood cell count at the time of harvest ranged from 1.2 to 18.1 x 10(9)/L. Results can be summarized as follows: the median number of cells collected per patient was 5.0 x 10(8)/kg (range 2.6 to 18.7), the median number of CD34+ cells was 1.8 x 10(6)/kg (range 0.27 to 3.8) and the median number of colony-forming units granulocyte-macrophage (CFU-GM) was 3.9 x 10(4)/kg (range 0 to 39). Twenty leukaphereses performed between days +33 and +77 of G-CSF treatment grew granulocyte macrophages and erythroid colonies in vitro. No colony growth was obtained from 20 leukaphereses performed before day +33 or after day +80. In six patients the total number of CFU-GM recovered were in the range described for autologous peripheral blood stem cell grafts. (2.6 to 39 x 10(4)/kg). In conclusion, this study suggests that circulating hematopoietic progenitors can be recovered after ALG priming and after at least 1 month of G-CSF treatment in a proportion of patients with SAA. Whether these cells will be suitable for autologous transplantation remains to be determined.  相似文献   
74.
A case of double aortic arch that was well visualized using transthoracic echocardiography is reported. A 38‐year‐old man underwent transthoracic echocardiography for the evaluation of dyspnea. A suprasternal view of transthoracic echocardiography showed the ascending aorta bifurcate to left and right aortic arches, with blood flow from the ascending aorta to bilateral aortic arches. The diagnosis of right side–dominant double aortic arch was made, and the patient's symptom was conceivably related to compression of the trachea due to a vascular ring. This report indicates the potential usefulness of transthoracic echocardiography for noninvasive detection of double aortic arch in adults.  相似文献   
75.
It is generally thought that dendritic cells (DCs) loaded with full-length tumor antigen could improve immunotherapy by stimulating broad T-cell responses and by allowing treatment irrespective of the patient''s human leukocyte antigen (HLA) type. To investigate this, we determined the specificity of T cells from melanoma patients treated with DCs loaded with mRNA encoding a full-length tumor antigen fused to a signal peptide and an HLA class II sorting signal, allowing presentation in HLA class I and II. In delayed-type hypersensitive (DTH)-biopsies and blood, we found functional CD8+ and CD4+ T cells recognizing novel treatment-antigen-derived epitopes, presented by several HLA types. Additionally, we identified a CD8+ response specific for the signal peptide incorporated to elicit presentation by HLA class II and a CD4+ response specific for the fusion region of the signal peptide and one of the antigens. This demonstrates that the fusion proteins contain newly created immunogenic sequences and provides evidence that ex vivo-generated mRNA-modified DCs can induce effector CD8+ and CD4+ T cells from the naive T-cell repertoire of melanoma patients. Thus, this work provides definitive proof that DCs presenting the full antigenic spectrum of tumor antigens can induce T cells specific for novel epitopes and can be administered to patients irrespective of their HLA type.  相似文献   
76.
Comorbidities are important for the disease outcome of COVID‐19, however, which underlying diseases that contribute the most to aggravate the conditions of COVID‐19 patients are still unclear. Viral clearance is the most important laboratory test for defining the recovery of COVID‐19 infections. To better understand which underlying diseases that are risk factors for delaying the viral clearance, we retrospectively analyzed 161 COVID‐19 clinical cases in the Zhongnan Hospital of Wuhan University, Wuhan, China between January 5 and March 13, 2020. The demographic, clinical and laboratory data, as well as patient treatment records were collected. Univariable and multivariable analysis were performed to explore the association between delayed viral clearance and other factors by using logistic regression. Survival analyses by Kaplan‐Meier and Cox regression modeling were employed to identify factors negatively influencing the viral clearance negatively. We found that hypertension and intravenous immunoglobulin adversely affected the time of viral RNA shedding. Hypertension was the most important risk factor to delay the SARS‐CoV‐2 virus clearance, however, the use of Angiotensin‐Converting Enzyme Inhibitors(ACEI)/Angiotensin Receptor Blockers(ARB) did not shorten the time for virus clearance in these hypertensive patients’ virus clearance. We conclude that patients having hypertension and intravenous immunoglobulin may delay the viral clearance in COVID‐19 patients.  相似文献   
77.
Common bile duct (CBD) stones are common in elderly adults, but the effect of aging on the presentation of CBD stones remains to be evaluated. Recent studies have demonstrated that the clinical presentation of CBD stones may vary with age. Younger adults may present with classical biliary colic symptoms, whereas elderly adults may have no unapparent clinical features. Younger adults with CBD stones were significantly more likely to have abnormal liver function tests than those without. The sensitivity and accuracy of transabdominal ultrasound scans in screening for CBD stones increases with age. Antibiotic agents should be promptly administered to individuals with CBD stones complicated by cholangitis, but the effects of pharmacotherapy on renal function should be considered in elderly adults. Endoscopic retrograde cholangiopancreatography (ERCP) is considered to be first‐line treatment for CBD stones, and endoscopic biliary sphincterotomy (EST) or endoscopic papillary balloon dilation (EPBD) along with ERCP is an adequate biliary drainage method in individuals with CBD stones. EPBD has a lower bleeding risk but higher post‐ERCP risk of pancreatitis than EST. Longer‐duration (>1 minute) EPBD may be preferred over EST because it is associated with a comparable risk of pancreatitis but a lower rate of overall complications, although recurrent cholangitis or unfavorable outcomes will increase during CBD dilation or in the presence of residual CBD stones.  相似文献   
78.
Secondary acute myeloid leukemia (sAML) traditionally has inferior outcomes compared to de novo AML. Allogeneic hematopoietic cell transplantation (HCT) is the sole potentially curative therapy. This study analyzes the outcomes for unmanipulated haploidentical HCT (haploHCT) for sAML using the Acute Leukemia Working Party (ALWP) registry of the European Society for Blood and Marrow Transplantation (EBMT). We identified 154 patients with sAML who underwent haploHCT from 2006 to 2016. Median age at HCT was 60 years with time from diagnosis to HCT 5 months. At transplantation, 69 patients were in first CR and 85 had active disease. Fifty‐seven (38.0%) patients underwent myeloablative conditioning and 97 (62.0%) reduced intensity conditioning (RIC) conditioning. Multivariate analysis showed that there was no difference in RI, nonrelapse mortality (NRM), leukemia free survival (LFS), overall survival (OS), or GVHD‐free/relapse free survival (GRFS) for conditioning intensity, age, performance status, or graft source. Active disease was associated with higher RI and inferior LFS, OS, and GRFS compared with patients in CR at time of transplant. T‐cell depletion with anti‐thymoglobulin resulted in higher NRM and inferior LFS, OS, and GRFS compared to post‐transplant cyclophosphamide (PTCy) (HR 2.25, 2.01, 2.16, and 1.73, respectively with P values <.05). Our data shows that haploHCT is a feasible alternative for sAML when matched transplantation is unavailable.  相似文献   
79.
Potential effectiveness of stored cord blood (non-frozen) for emergency use   总被引:1,自引:0,他引:1  
Bone marrow has been used for a number of years to assist patients who have accidentally received potentially lethal levels of irradiation. The intent of the transplant is to replace the victim's own bone marrow that has been injured from the irradiation or to act as temporary support to allow the patient's own marrow to recover. Following the Chernobyl disaster, some victims received bone marrow that was HLA matched or partially matched. However, donor marrows were difficult to obtain in adequate numbers; as a substitute for bone marrow, frozen fetal liver cells were used as a source of hematopoietic stem cells. The use of fetal livers, however, was unsuccessful. Human umbilical cord blood, currently considered an excellent source of hematopoietic stem cells, was not used at Chernobyl. For several years, we have been able experimentally to keep SJL/J mice alive with the use of human umbilical cord blood after the animals received lethal levels of irradiation. This finding suggests that under certain conditions human cord blood does not have to be HLA matched to facilitate rescue from irradiation. In addition, there are reports of unmatched HLA cord blood being used successfully for marrow transplantation. If human cord blood does not have to be matched for HLA, there may be emergency cataclysmic circumstances where the availability of umbilical cord blood may be of considerable value. To simulate a clinical situation such as a nuclear accident, in which human cord blood might serve as a source of stem cells for marrow transplantation, we attempted to rescue immunocompetent mice after 900 cGY of irradiation with the use of (nonfrozen) human cord blood stored in a blood bank. The blood was stored under routine conditions (3–6 °C) for 5 and 7 days in special bags that allow transmission of oxygen. Following lethal levels of irradiation, the cord blood was administered to the animals and a significant survival rate was obtained.  相似文献   
80.
Oxidative stress can generate a mass of oxygen free radicals (OFR) in the cells, and these OFRs can induce several acute and chronic symptoms and diseases. If the amount of the generated OFRs overwhelms the antioxidant capacity of the cells, the pathophysiological changes may lead to the death of the cell or the development of chronic degenerative diseases.  相似文献   
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