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101.
Severe combined immunodeficiency (SCID) is potentially correctable by bone marrow transplantation if a patient has a suitable histocompatible donor. In the absence of an HLA-matched donor, lethal graft-versus-host disease (GVHD), which is mediated by alloreactive donor T cells, may occur. In an attempt to prevent GVHD in one SCID patient lacking a matched donor, we treated maternal haplomismatched bone marrow with a unique nonmitogenic T-cell-specific monoclonal antibody (anti-T12) and complement to remove mature T cells. Despite the removal of greater than 99% mature T cells, the child developed significant life-threatening GVHD, which was terminated by a 5-day course of intravenous anti-T12. Subsequently, immune reconstitution occurred by 6 wk: the mature circulating T cells proliferated in response to soluble and allo-antigens in vitro and provided help for B-cell immunoglobulin synthesis. The patient was removed from a protective environment and discharged without evidence of further infection. Both HLA and chromosomal analyses showed that the circulating cells in the patient were of maternal origin. More importantly, the maternal T cells were no longer reactive with recipient cells. Mixing experiments indicated that the state of tolerance that resulted in this chimera was not due to active suppression. We conclude that HLA-mismatched transplantation for SCID can be undertaken if mature alloreactive donor T lymphocytes are depleted before and after bone marrow grafting.  相似文献   
102.
The combination of captopril and nitroglycerin early after acutemyocardial infarction (AMI) could lead to a dangerous decreasein blood pressure coronary perfusion. To evaluate the safetyaspects and haemodynamic effects of this combination, we studied36 first ‘Q wave’ thrombolysed anterior wall AMIpatients during the 24 h following the onset of symptoms. Afterwards, thrombolysis patients received a continuous infusionof nitroglycerin and were submitted to pulmonary artery catheterization.Those patients with mean arterial pressure (MAP) 70 mmHg, cardiacindex 2.21. min–1.m–2, and wedge pressure 10 mmHgwere included and randomized to receive 6.25 mg of captoprilevery 6 h on the first day and 12.5 mg qid on the second f MAP 70mmHg (group 1). A second group (group 2) received a placebo.Haemodynamic parameters were determined after 1, 6 and thenevery 6 h up to 48 h after basal measurements. Significant differenceswere observed only for the MAP and the rate-pressure product(reduction in group 1 values, P <0.05). However, MAP wasmaintained within acceptable limits. Our data support the factthat the combination of captopril and nitroglycerin in the earlyhours of a non-complicated anterior wall AMI is safe, and couldguarantee its use in large clinical trials to determine theeffects on left ventricle remodelling and survival after AMI.  相似文献   
103.

Background

Dietary oleic acid may prevent pancreatic ductal adenocarcinoma (PDA) by reducing hyperinsulinaemia which can otherwise promote DNA damage and tumour growth. Results from previous epidemiological studies investigating oleic acid are inconsistent. This study aims to clarify the relationship between dietary oleic acid intake and the risk of developing PDA using nutritional information from food diaries plus published serum biomarker data from HbA1c.

Methods

23,658 participants, aged 40–74 years, were recruited into EPIC-Norfolk and completed 7-day food diaries which recorded; foods, brands and portion sizes to calculate nutrient intakes. Serum HbA1c was measured at recruitment in 11,147 participants (48.7% of cohort). Hazard ratios (HRs) for quintiles of dietary oleic acid intake and serum HbA1c were estimated using Cox regression. Additional analyses were made according to whether body mass index (BMI) was greater or less than 25?kg/m2 as this influences hyperinsulinaemia.

Results

88 participants (55% women) developed PDA after a mean follow-up of 8.4 years (SD?=?3.9) (mean age at diagnosis?=?72.6 years, SD?=?8.8). A decreased risk of PDA was associated with increased dietary oleic acid intake (highest vs lowest quintile, HR?=?0.29, 95% CI?=?0.10–0.81, P trend across quintiles?=?0.011), with statistical significance maintained when BMI>25?kg/m2 but not if BMI<25?kg/m2. An elevated serum HbA1c was associated with increased risk of disease (highest vs lowest quintiles, HR?=?6.32, 95% CI?=?1.38–28.89, P for trend?=?0.004).

Conclusions

The data supports a protective role of oleic acid against development of PDA in those with higher BMIs possibly through influencing hyperinsulinaemia. Oleic acid intake should be accurately measured in future aetiological studies.  相似文献   
104.
Using accepted diagnostic criteria we have selected, for study, 160 patients with Crohn's disease involving the colon. There is a remarkable discrepancy between the clinical diagnosis prior to or at the time of initial admission to this hospital and the diagnosis following definitive investigation and observation of the progression of disease.
The peak age incidence occurred in the second decode The colitis group showed a greater percentage of patients over 30 years of age. Although histopathology was not obtained in all patients, there appeared to be sparing of the ascending colon in a small percentage (9%) of patients with ileocolitis.
Comparison of the clinical features of granulomatous disease limited to the colon and granulomatous ileocolitis shows a significantly greater incidence of extraintestinal symptoms and overt bleeding in the former. Nausea, vomiting, subacute obstruction, abdominal mass and internal fistulas were substantially more common in ileocolitis but the difference was not statistically significant. In this series retroperitoneal abscess did not occur in patients with disease localized to the colon. In the 10 patients with ileocolitis who developed an abscess, however, the site of fistula was the colon in four patients. In one of these, the abscess was left-sided.  相似文献   
105.
106.
Stem Cell Migration and Proliferation During Severe Anemia   总被引:3,自引:2,他引:3  
The pluripotential stem cell (CFU) compartment of marrow and spleen wasevaluated in mice subjected to an intense erythroid stimulus associated withphenylhydrazine-induced anemia. Erythroid hyperplasia occurred in both marrow and spleen. CFU in the marrowgradually declined to approximately 50per cent of control levels (day 5) whiletheir numbers in the spleen increased(fourfold) by day 3 and were maintainedat this level for several days. Thesechanges in numbers of marrow andsplenic CFU were not associated withCFU proliferation. Thereafter, CFU inthe marrow, but not in the spleen, entered active cell cycle. The data suggestthat CFU migrate from marrow to spleenduring the demands of severe anemia.The induction of marrow CFU into cyclefurther suggests a negative feedback,which, perhaps through cell-cell interaction, maintains stem cells at a criticalcompartment size. The failure of splenicCFU to cycle may reflect the converseeffect, i.e. an inhibition on stem cell proliferation in the wake of an expandedstem cell pool.

Submitted on March 17, 1970 Revised on May 14, 1970 Accepted on June 9, 1970  相似文献   
107.
Bartonella henselae is associated with a wide spectrum of clinical manifestations, including cat scratch disease, endocarditis and meningoencephalitis, in immunocompetent and immunocompromised patients. We report the first molecularly confirmed case of B. henselae infection in an AIDS patient in state of Rio de Janeiro, Brazil. Although DNA sequence of B. henselae has been detected by polymerase chain reaction in a lymph node biopsy, acute and convalescent sera were nonreactive.  相似文献   
108.
109.
110.
This is the second part of a two‐part piece on self‐adhesive resin cements; Part I was presented in the previous issue of the Journal. Here in Part II, the specific topics concerning self‐adhesive cements are clinical performance, post‐cementation sensitivity, and cementation of endodontic posts.  相似文献   
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