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21.
OBJECTIVE: The primary objectives of this study were to compare the effect of spinal manipulation vs. sham manipulation on a) circulating plasma levels of the prostaglandin F2a metabolite, 15-keto-13,14-dihydroprostaglandin (KDPGF2a), b) perceived abdominal and back pain and c) perceived menstrual distress in women with primary dysmenorrhea. DESIGN: This randomized clinical pilot study investigated the outcome measures before and after either a spinal manipulation treatment (SMT) or a sham manipulation. SETTING: All subjects were treated at the National College Chiropractic clinic, a private chiropractic clinic in the suburban Chicago area. PARTICIPANTS: Forty-five women with a history of primary dysmenorrhea were recruited from the local community. The volunteers ranged in age from 20-49 (mean age = 30.3 yr), and were entered into the study between April 1990 and January 1991. Twenty-four were randomly assigned to the spinal manipulation group and 21 were assigned to the sham group. INTERVENTIONS: Subjects treated with spinal manipulation were placed in a side-lying position with the bottom leg straight and the top leg flexed at the knee and hip. They received a high-velocity, short lever, low-amplitude thrust to all clinically relevant vertebral levels within T10 and L5-S1 and the sacroiliac joints. In the sham manipulation, subjects were placed in a side-lying position with both hips and knees flexed. Their manipulation consisted of a similar thrust administered to the midline base of the sacrum. OUTCOME MEASURES: Perceived abdominal and back pain were measured with a visual analog scale, and menstrual distress was measured with the Menstrual Distress Questionnaire. Both were administered 15 min before and 60 min after treatment. Blood samples were collected by venipuncture for the determination of plasma levels of KDPGF2a at the same times. The plasma was then assayed for KDPGF2a by radioimmunoassay. RESULTS: Analysis of covariance and paired Student's t tests were used for the statistical evaluation. Immediately after treatment, the perception of pain and the level of menstrual distress were significantly reduced by SMT. This reduction was associated with a significant reduction in plasma levels of KDGPF2a in the SMT group. A significant and similar reduction in plasma KDPGF2a also occurred in the sham group, indicating that a placebo effect was associated with a single sham intervention. CONCLUSIONS: This randomized pilot study suggests that SMT may be an effective and safe nonpharmacological alternative for relieving the pain and distress of primary dysmenorrhea. However, the large change in KDPGF2a observed in both treatment groups clearly indicates that further studies with more subjects, studied over a longer time frame, are needed to resolve the question of a placebo effect.  相似文献   
22.
Analysis of extant clinical records is receiving increased emphasis in nursing investigations. Appropriate use of this approach to patient research requires careful attention to data management, including assessment of reliability. Percent agreement, phi, and Kappa all serve as estimates of interrater reliability in the analysis of data. Kappa has particular merit as a measure of interrater reliability; it also has some peculiar problems in implementation and interpretation. The nature and computation of Kappa and its application in analysis of clinical data are discussed.  相似文献   
23.
Carcinoma of the body and tail of the pancreas.   总被引:13,自引:0,他引:13  
Recently, several institutions have reported improved results in the treatment of patients with carcinoma of the head of the pancreas. In an attempt to determine whether similar trends could be demonstrated for patients with carcinoma of the body and tail of the pancreas, the records of all 113 patients with an adenocarcinoma of the body or tail of the pancreas treated at The Johns Hopkins Hospital between 1972 and 1989 were reviewed. The patients were divided into two groups: those diagnosed between 1972 and 1982 (41 patients) and those between 1983 and 1989 (72 patients). No significant differences in tumor stage were observed between the two groups. The proportion of patients who underwent surgery decreased from 68% to 47% (p = 0.02). The number of patients who had bypass operations (15% versus 17%) or pancreatic resection (5% versus 10%) was similar in the two groups, but the proportion of patients who underwent exploratory laparotomy with biopsy only decreased from 49% to 21% (p = 0.002). The postoperative 30-day mortality (7% versus 3%), postoperative morbidity (18% versus 21%), median survival (4 months versus 3 months), and the 1-year survival (8% versus 9%) did not differ significantly between the two groups. One patient survived for 6 years after resection, and another patient is still alive 3 years after resection. Thus, unlike adenocarcinoma of the head of the pancreas, it appears that treatment results for patients with adenocarcinoma of the body or tail of the pancreas have not improved in recent years, the only change being a decreased need for exploratory laparotomy with biopsy only.  相似文献   
24.
Corneal pathophysiology with contact lens wear   总被引:2,自引:0,他引:2  
Contact lens wear induces a wide spectrum of changes in the appearance and function of the cornea. The most salient effect of lens wear is the hypoxically induced reduction in the rate of metabolic activity of the corneal epithelium and its sequellae. Other important alterations to corneal health associated with contact lens wear may be caused by antigenic and toxic stimuli, mechanical forces, osmotic effects and carbon dioxide retention. Perhaps the most important task facing the contact lens clinician is to distinguish between an acceptable state of physiological modification and an anomalous or pathological state of hypofunction. In this article, we review the assortment of corneal changes primarily on the basis of the causative agents and time scale with reference to the physical and chemical processes leading to the observed signs or symptoms. This procedure allows a strong foundation for understanding the etiology and management principles for the variety of effects that contact lenses may have on the cornea.  相似文献   
25.
Strains of Staphylococcus aureus, isolated from the effluentof patients with peritonitis on CAPD (continuous ambulatoryperitoneal dialysis), adhered well to both cultured human mesothelialcells and to fibronectin, but not to laminin or gelatin. Mesothelialcells grown in medium M199 exhibited more surface fibronectincompared to cells grown in MEM-Dval and demonstrated higherlevels of S. aureus adherence. Soluble fibronectin concentrations up to lOµg/ml increasedthe adherence of S. aureusto cultured mesothelial cells. Thedose-response curve was consistent with the binding of fibronectinto a saturable receptor of apparent dissociation constant (KD)= 1.7xlO–10 M. This corresponds closely to the KD (2xlO–10M) of the staphylococcal fibronectin-binding protein. S. aureus adherence was increased following the preincubationof mesothelial cell monolayers with interleukin-1 and was maximalafter 6 h preincubation. Treating mesothelial cells with interferon-gammafor 48–72 h reduced the adherence of S. aureus.  相似文献   
26.
J V Sitzmann  Y Wu    J L Cameron 《Annals of surgery》1994,219(5):500-507
OBJECTIVE: To characterize angiotensin-II receptor density and affinity in normal and cirrhotic livers and in hepatocellular and metastatic colorectal cancer. SUMMARY BACKGROUND DATA: Several studies have indicated a possible beneficial effect of angiotensin-II as a biologic response modifier in the treatment of hepatic or metastatic colon cancer. This is based on evidence that angiotensin-II will cause a selective increase in arterial vasoconstriction in normal liver compared with tumor. METHODS: Human hepatoma (5), metastatic colon (10), or cirrhotic (3) liver was obtained. Non-tumor-bearing regions served as normal liver. Angiotensin-II receptor binding was determined on membranes with 125I-angiotensin-II and in situ studies were performed using the biotin-avidin detection system. RESULTS: Angiotensin-II receptor density was markedly down-regulated in tumor compared with normal or cirrhotic liver. CONCLUSIONS: A loss of angiotensin-II receptors occurs on the neovasculature of hepatic tumors.  相似文献   
27.
28.
Repeat hepatic resections for metastatic colorectal cancer.   总被引:7,自引:0,他引:7       下载免费PDF全文
OBJECTIVE: The authors weighed the risks and benefits of repeat liver resections for colorectal metastatic disease. METHOD: In the 6-year period between January 1985 and June 1991, 499 patients underwent liver resections for colorectal metastases at the Memorial Sloan-Kettering Cancer Center. Of these, 25 patients had repeat surgical resections for isolated recurrent disease to the liver. The clinical data for these patients were reviewed. RESULTS: The median interval between the two resections was 11 months. There were no perioperative deaths, and the complication rate was 28%. Median follow-up after the second liver resection is 19 months, with median survival of 17 months for nonsurvivors. Although the median survival after the second resection is 30 months, 20 of the 25 patients have had recurrences with a median disease-free interval of only 9 months. No characteristic of primary or metastatic disease predicted outcome, including time between presentation of the primary and development of liver metastases, disease-free interval after the first liver resection, and bilobar liver involvement. CONCLUSIONS: Although repeat liver resections can be performed safely and improves survival, the likelihood of cure from such resection therapy is low. This likelihood of further recurrences encourage studies of adjuvant or alternative treatments of this population.  相似文献   
29.
Socioeconomic status and risk for substandard medical care.   总被引:12,自引:0,他引:12  
H R Burstin  S R Lipsitz  T A Brennan 《JAMA》1992,268(17):2383-2387
OBJECTIVE--To assess whether the socioeconomic status of the patient was associated with the risk of adverse events, defined as medical injuries caused by medical management, and the proportion of these events that resulted from substandard care. SETTING--51 hospitals in New York State. METHODS--Rates of medical injury and substandard care by gender, race, income, and payer status were developed from reviews of 30,195 medical records in New York in 1984. We evaluated these socioeconomic parameters in a multivariate analysis, while controlling for hospital-level factors. RESULTS--We found that uninsured patients (odds ratio, 2.35; 95% confidence interval, 1.40 to 3.95) were at greater risk for substandard care. The characteristics of the hospitals to which patients were admitted did not affect this result. Race, gender, and income were not independently associated with risk for medical injury or substandard care in multivariate analyses. CONCLUSION--Our findings suggest that the uninsured are at greater risk for suffering medical injury due to substandard medical care.  相似文献   
30.
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