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J Marshall

Publications and source records attributed to J Marshall.

At least 469 records · Page 26Linked to original sources
PubMed1983

A case-control study of dietary and nondietary factors in ovarian cancer.

A case-control study is presented that estimates ovarian cancer risk for various factors, including diet. Data collected by interview between 1957 and 1965 for 274 white women aged 30-79 years with epithelial carcinoma of the ovary are compared to data similarly collected for 1,034 hospital controls. Relative risk estimates are presented for the total group as well as for premonopausal (ages 30-49) and postmenopausal (ages 50-79) are groups. In the total group, cancer risk increased with increasing age at first marriage (P less than .01) and previous history of benign breast disease (P less than 0.1), and risk decreased with increasing number of previous pregnancies (P less than .01). In the 50- to 79-year age group, a marginally significant trend for decreasing risk with increasing obesity was observed (P less than .10). There was no significant risk (i.e., P less than .10) associated with the consumption of alcohol, cigarettes, coffee, tea, total dietary protein, vitamin C, or fat at any age. In the 30- to 49-year age group only, increased risk (P less than .01) was seen in women reporting diets low in fiber and vitamin A from fruit and vegetable sources. Multiple regression analysis demonstrated that the apparent protective effect of vitamin A in the 30- to 49-year age group (but not dietary fiber) was independent of the nondietary factors analyzed in this study (P less than .05).

Adult↗
PubMed1983

Individualizing theophylline therapy: the impact of clinical pharmacokinetics on patient outcomes.

We have studied 19 male patients whose theophylline therapy was individualized by a clinical pharmacokinetics service and 34 male patients with empirically derived dosages. All patients were admitted to the medical intensive care unit. Patients in the pharmacokinetics group had fewer adverse reactions (15.7 vs. 50%), shorter intensive care unit stay (6.6 +/- 5.5 vs. 12.4 +/- 16.3 days), shorter hospital stay (15.4 +/- 10 vs. 22.3 +/- 14.1 days), and a shorter period of time to be placed on oral therapy (5.2 +/- 3.1 vs. 8.6 +/- 7.2 days) than the group with empirically derived regimens. The pharmacokinetic method used to individualize theophylline therapy offered an accurate and efficient method of achieving therapeutic concentrations. We conclude that the use of clinical pharmacokinetics to individualize theophylline therapy offers substantial benefits over empirical assessments.

Aged↗
PubMed1982

Effect of plasma exchange on blood viscosity and cerebral blood flow.

The effects of plasma exchange using a low viscosity plasma substitute on blood viscosity and cerebral blood flow were investigated in eight subjects with normal cerebral vasculature. Plasma exchange resulted in significant reductions in plasma viscosity, whole blood viscosity, globulin and fibrinogen concentration without affecting packed cell volume. The reduction in whole blood viscosity was more pronounced at low shear rates suggesting an additional effect on red cell aggregation. Despite the fall in viscosity there was no significant change in cerebral blood flow. The results support the metabolic theory of autoregulation. Although changes in blood viscosity appear not to alter the level of cerebral blood flow under these circumstances, plasma exchange could still be of benefit in the management of acute cerebrovascular disease.

Adult↗
PubMed1982

The cause and prognosis of strokes in people under 50 years.

A study of 192 personal cases of completed stroke, reversible ischaemic neurological deficit (RIND) or transient ischaemic attack (TIA) in patients aged 10-49 years seen between 1961 ad 1979 inclusive is reported. Three died acutely; 189 were followed for up to 15 years. The main cause of the initial event was atheromatous or hypertensive vascular disease. Of the 90 patients whose initial event was a completed stroke 19(21%) developed a second stroke, whereas only 4 of the 78 patients with TIA suffered a stroke later. In the entire series there were 6 cardiac deaths and one from mesenteric thrombosis during the follow-up period. The risk of stroke following TIA is less in persons under 50 years than in the older age group. The risk of a second stroke following an initial stroke depends on whether or not there is evidence of vascular disease. In the absence of such evidence the risk is small; in the presence of evidence it is high, being of the order of 20%.

Adolescent↗
PubMed1982

Skin carcinogenesis and promoter binding characteristics in different mouse strains.

The sensitivity of various mouse strains to skin carcinogenesis has been investigated in two ways; (i) by comparing carcinogenesis induced by treatments involving both the application of tumour promoters and the application of single or multiple doses of a carcinogen, and (ii) by comparing the binding characteristics of the tumour promoter [3H]phorbol-12,13-dibutyrate to particulate skin preparations. The mouse strains tested were Swiss albino, Balb/c, C3H, LACA and AKR/J. Although some differences were apparent, Swiss albino, LACA and C3H mice were generally sensitive to skin carcinogenesis by both benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene, either with or without promotion with croton oil. AKR/J mice were sensitive to both carcinogens with promotion but relatively insensitive in the absence of promotion. Balb/c mice had low sensitivity except when exposed to repeated low doses of benzo[a]pyrene. The [3H]phorbol-12,13-dibutyrate binding characteristics of particulate skin preparations from all strains were indistinguishable.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

Diet in the epidemiology of breast cancer.

A variety of studies have shown that diets high in fat, particularly polyunsaturated, have enhanced the production of tumors in animals challenged with chemical carcinogens. Other studies have found an apparent contradiction of no difference in the incidence of breast cancer among women with varying levels of serum cholesterol as measured decades earlier. The present study concerns 2024 breast cancer cases and 1463 control patients without neoplasms or pathology of the reproductive and digestive organs, seen at Roswell Park Memorial Institute from 1958 to 1965. Based upon the assessments of their varying ingestion of fats from their own reports of diets, no difference in risk was found. Similarly, there was no difference in risk of breast cancer associated with ingesting diets containing various levels of either vitamin C or the cruciferous vegetables. Risk for breast cancer in women 55 years of age and older increased somewhat with decreases in ingestion of foods containing vitamin A.

Aging↗
PubMed1982

Chest physiotherapy fails to prevent postoperative atelectasis in children after cardiac surgery.

In a prospective, randomized study, the effectiveness of chest physiotherapy (CPT) was evaluated in preventing postoperative atelectasis in children after heart surgery. Postoperative clinical variables and chest x-ray findings of atelectasis were compared in two groups: 19 patients receiving CPT and 25 patients not receiving CPT (NCPT). Chest physiotherapy was associated with significantly more frequent (p less than 0.01) and more severe (p less than 0.01) atelectasis than NCPT. Atelectasis was not significantly associated with temperature elevation, age, or presence of preoperative left-to-right shunt.

Child↗
PubMed1982

Treatment of lipid keratopathy with the argon laser.

Twenty-two patients with lipid keratopathy were treated with argon laser photocoagulation to the feeder vessels. Two were grafted just over a week after treatment and the corneal discs examined histologically. The remainder of the patients were followed up for a least a year. In 6 cases the visual acuity improved, in 3 deteriorated, and in 10 did not change. The density and extent of the lipid deposition were diminished in 50% of cases. The commonest complications were bleeding into the lipid keratopathy and iris damage. The only serious problem was a disciform type of lipid keratopathy that flared up after treatment. Suggestions are made on improvements in the technique of laser application.

Adult↗
PubMed1982

Amaurosis fugax: some aspects of management.

Fifty-one patients with amaurosis fugax were followed for a mean of 4.9 years from their first attack. Females predominated under the age of 50 years in contrast to men who presented in the older age group. Minor permanent visual sequelae occurred in only three patients, but cerebral vascular symptoms were present at some time in just under half the group. A range of abnormalities was identified on cerebral angiography and some of these correlated with certain clinical findings. Twenty patients were treated by surgery and permanent relief of significant improvement in symptoms occurred in 14. A group of patients who were at greater risk of cerebral vascular complications following angiography and surgery was identified. It is concluded that careful patient selection is necessary before surgery is recommended but that in a significant number of cases with relatively focal atheroma confined to one proximal internal carotid artery an excellent long term result following surgery may be expected.

Adult↗
PubMed1982

Haematocrit, hypertension and smoking in patients with transient ischaemic attacks and in age and sex matched controls.

The blood pressure, smoking habit and haemotocrit of 154 patients with transient ischaemic attacks and 191 age-and sex-matched neurological controls were studied. Regression analysis revealed that the haematocrit value was related to both systolic and diastolic blood pressure, and to smoking. Smoking elevated the haematocrit by 1.9 +/- 0.59 in males and by 2.18 +/- 0.68 in females. When these associations were allowed for there was still evidence of a higher haematocrit in patients with transient ischaemic attacks (plus 1.44 +/- 0.56 in males and 0.75 +/- 0.75 in females p less than 0.02). The role of an elevated haematocrit in the pathogenesis of cerebrovascular disease and its management are briefly discussed.

Adult↗
PubMed1982

An improved method of right ventricular gated equilibrium blood pool radionuclide ventriculography.

Gated blood pool radionuclide ventriculography provides a means for obtaining repeated studies of both cardiac ventricles with a single dose of radionuclide. Quantitative assessment of right ventricular (RV) function using this technique has been complicated by several technical problems. We describe a new method of RV blood pool analysis which attempts to solve these problems using well-established concepts for left ventricular (LV) blood pool analysis: (1) variable regions of interest; (2) computer edge detection with operator intervention; and (3) computer selected background. Results showed a strong linear correlation between gated first pass RV ejection fraction (RVEF) and the gated blood pool RVEF (n = 22; r = 0.93; blood pool RVEF = 0.03 + 0.89 X first pass RVEF; Sy.x = 0.04). There was also a strong linear correlation between LV and RV stroke counts in patients without valvular regurgitation, intracardiac shunts, or ventricular aneurysms (n = 19; r =0.86; RV counts = 72 + 0.94 X LV counts; Sy.x = 116). In terms of both of these validation standards this method proved superior to three published methods of RV blood pool analysis that used hand-drawn regions, and is suitable for analysis of rest, exercise, and intervention studies of RV function.

Adult↗
PubMed1982

Caffeine consumption and benign breast disease: a case-control comparison.

In this case-control comparison of 323 women with benign breast disease and 1,458 controls, no differences were noted in the coffee and tea consumption patterns of the cases and controls. These findings do not support the recent suggestion of Minton, et al, that methylxanthine ingestion is causally related to benign breast disease or breast cancer.

Adult↗
PubMed1982

Clinical NMR imaging of the brain: 140 cases.

Cranial nuclear magnetic resonance (NMR) scans were performed on 13 healthy volunteers and 140 patients with a broad spectrum of neurologic disease and compared with x-ray computed tomography (CT) scans. The NMR scans included a variety of sequences reflecting proton density, blood flow, T1, and T2 as well as transverse, sagittal, and coronal images. White matter, gray matter, and cerebrospinal fluid were clearly distinguished in the normal brain with inversion-recovery (IR) sequences, and normal progressive myelination was demonstrated in infants and children. Acute hemorrhages displayed short T1 values, but other pathologic processes such as infarction, infection, demyelination, edema, and malignancy were associated with long T1 values. Cysts had very long T1 values (about that of cerebrospinal fluid). Spin-echo (SE) sequences showed increased values of T2 in a variety of conditions and highlighted lesions against the relatively featureless background of the remaining brain. With inversion-recovery scans, different stages of infarction were recognized in the hemispheres. NMR was more useful than CT in demonstrating brainstem infarction. The white matter lesions in demyelinating diseases were well demonstrated with NMR scans. Many more lesions were observed in multiple sclerosis with NMR than with CT. Benign tumors were well seen and usually had shorter T1 values than malignant tumors. Mass effects from tumors were generally better demonstrated with NMR than with CT, including more subtle mass effects such as displacement of the external capsule. Abnormalities were seen in diseases of the basal ganglia, including marked atrophy of the head of the caudate nucleus in Huntington chorea. Advantages of NMR imaging include the high level of gray-white matter contrast, lack of bone artifact, variety of possible sequences, transverse, sagittal, and coronal imaging, sensitivity to pathologic change, and lack of known hazard. Disadvantages include lack of bone detail, limited spatial resolution, lack of contrast agents, and cost. Promising directions for future clinical research include developmental neurology, tissue characterization with T1 and T2, assessment of blood flow, and the development of contrast agents. Much more detailed evaluation will be required, but NMR seems to be a potentially important addition to existing techniques of neurologic diagnosis.

Adolescent↗