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The poor perinatal outcome of pregnant women with chronic hypertension depends on their increased susceptibility to superimposed preeclampsia. There is no direct evidence that this is mediated by hypertension and reduced by antihypertensive treatment. In particular, the arterial lesions of the uteroplacental circulation in preeclampsia also occur in normotensive individuals and would be unusual types of pressure-induced injury. Thus, there is no compelling reason for treating hypertension below a threshold (170/110 mm Hg) above which maternal safety becomes the main concern.  相似文献   
63.
Two studies of patient education programs tested hypotheses regarding the relationship between structural, attitudinal, and resource variables and reported receipt of instruction by patients and delivery of instruction by providers. Three predictor variables--degree of structure for implementation, provider perception of reinforcement for doing patient education, and perceived payoffs from the program, were significantly related to measures of the dependent variable. Age of the program, administrator support for social change and staff support for the program, did not show significant relationships with receipt/delivery of instruction. Future studies might investigate: how coordinative functions are carried out rather than whether a coordinator for the program has been named, the relationship between financial condition of the hospital and ability to deliver patient education services, and the relationship between patient education resources and outcome variables such as health care services used and cost. Research about resources necessary to ensure adequate delivery of instruction to patients is as important as is research about resources necessary to ensure adequate delivery of instruction to patients is as important as is research about the design of instruction.  相似文献   
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Flow cytometry has enabled the objective assessment of cellular morphology and activity, which can also be biochemically evaluated by measuring products of cellular metabolism, such as cyclic 3'5' guanosine monophosphate (cGMP). Using paraffin-embedded formalin-fixed material obtained from the primary operation, an analysis of the correlation between nuclear ploidy and the proliferative index (PI) as quantified by flow cytometry with pre-treatment urinary cGMP was performed in 40 epithelial ovarian cancer (EOC) patients. The majority of the study group had advanced disease (28 FIGO III/IV) and residual disease (31). All but three (stage I) patients received single agent high dose cisplatinum as first-line therapy (100 mg m-2 x 5); in patients with evaluable disease there was a response rate of 64%. Thirty-one patients have died; the median survival of the study population being 27 months. There was a significant association between cGMP and PI. Significantly more aneuploid tumours had elevated PI values (P = 0.02). No variable predicted response. An initial univariate log rank analysis identified stage, the amount of residual disease, cGMP and PI as prognostic factors. Because of the interrelation between these and other factors and because PI did not conform to the proportional hazards model, a multivariate stepwise discriminant analysis was performed using survival at 36 months (the minimum follow-up for surviving patients) as the end-point. On the basis of this analysis, stage and residual disease were the most important prognostic factors, but cyclic GMP continued to have prognostic value even when these other factors were entered into the predictive model. However, the additional information gained has little clinical relevance.  相似文献   
65.
J F Redman 《Urology》1987,29(2):166-169
It is frequently stated that extravasation of urine after intrarenal surgery is deleterious to renal wound healing causing fibrosis or granulation tissue. A study using dogs was designed to test the hypothesis that the contact of urine with incised renal parenchyma may cause altered wound healing. This study showed that exposure of the renal parenchyma to extravasated urine from open collecting structures did not alter renal healing.  相似文献   
66.
Outpatient percutaneous nephrostolithotomy   总被引:2,自引:0,他引:2  
Technical advances and operator experience have resulted in a rapid and marked streamlining of the percutaneous approach to renal calculi. The development of nephrostomy tract balloon dilators, improved grasping instruments and the use of assisted local anesthesia have been integral in reducing the morbidity and cost of the procedure. We report our initial favorable experience in the use of percutaneous stone removal on an outpatient basis. All 5 patients underwent an uncomplicated 1-stage stone removal. Cost for outpatient percutaneous stone removal was substantially less than for surgery or extracorporeal shock wave lithotripsy.  相似文献   
67.
Arteriovenous malformations of the extremities: MR imaging   总被引:3,自引:0,他引:3  
Cohen  JM; Weinreb  JC; Redman  HC 《Radiology》1986,158(2):475-479
Eight patients with angiographically proved arteriovenous malformations (AVMs) of the extremities (seven congenital, one posttraumatic) were evaluated with magnetic resonance (MR) imaging using a 0.35-T superconducting system and spin-echo pulse sequences. Congenital AVMs appeared as accumulations of dilated tortuous blood vessels infiltrating the involved muscles. A posttraumatic acquired AVM of the shoulder consisted of a large feeding artery associated with a pseudoaneurysm and a soft-tissue mass. MR imaging allowed precise anatomic localization and provided details concerning the size and extent of the AVMs. The relationship of AVMs to specific muscle groups, bones, and vascular structures could be accurately determined. Although major feeding and draining vessels were identified, the exact arteries and veins supplying and draining the AVM could not be ascertained. Images obtained in the transverse plane consistently yielded the most useful information. MR imaging and angiography may be complementary techniques in the initial evaluation, follow-up, and treatment planning of AVMs of the extremities.  相似文献   
68.
Objective To determine women's preferences for and reported experience with medical test decision‐making. Design Computer‐assisted telephone survey. Setting and participants Six hundred and fifty‐two women resident in households randomly selected from the New South Wales electronic white pages. Main outcome measures Reported and preferred test and treatment (for comparison) decision‐making, satisfaction with and anxiety about information on false results and side‐effects; and effect of anxiety on desire for such information. Results Overall most women preferred to share test (94.6%) and treatment (91.2%) decision‐making equally with their doctor, or to take a more active role, with only 5.4–8.9% reporting they wanted the doctor to make these decisions on their behalf. This pattern was consistent across all age groups. In general, women reported experiencing a decision‐making role that was consistent with their preference. Women who had a usual doctor were more likely to report experiencing an active role in decision‐making. More women reported receiving as much information as they wanted about the benefits of tests and treatment than about the side‐effects of tests and treatment. Most women wanted information about the possibility of false test results (91.5%) and test side‐effects (95.6%), but many reported the doctor never provided this information (false results = 40.0% and side‐effects = 31.3%). A substantial proportion said this information would make them anxious (false results = 56.6% and side‐effects = 43.1%), but reported they wanted the information anyway (false results = 77.6% and side‐effects = 88.1%). Conclusions Women prefer an active role in test and treatment decision‐making. Many women reported receiving inadequate information. If so, this may jeopardize informed decision‐making.  相似文献   
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