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71.
Alteration of the fibrinolytic system is considered to be important in the development of deep venous thrombosis (DVT). Using specific assays for tissue plasminogen activator (t-PA) activity, t-PA inhibitor (PAI) and t-PA antigen, we measured these activities in 16 women who developed DVT during their pregnancies. A group of 24 healthy females of comparable age was studied as controls. PAI was increased in 87% of these patients compared to the healthy controls. In some of these patients a defect in release of t-PA from vascular endothelium was found as well. The site at which blood was sampled for analysis appeared to be an important criterion in the ex vivo assessment of functional t-PA reserve and PAI levels, though relatively less so for the latter measurement. The unaffected lower limbs, relative to the unaffected upper limbs, showed an increase in PAI and a demonstrable decrease in t-PA release, both representing increased risk factors for rethrombosis. The affected lower limbs showed similar but more accentuated changes in these parameters.  相似文献   
72.
We conducted a study to compare the performance of serum and urine pregnancy tests in the evaluation of gynecologic patients presenting to our ED. The overall efficiency of the two tests was very similar: 99.5% for the serum test, and 97.6% for the urine test. In patients proven to have ectopic pregnancies, however, the serum test was positive in 100%; the urine test was positive in only 60%. The serum test misclassified (gave false-negative or false-positive results) in three of 607 patients (0.5%). The urine test misclassified 14 of 607 patients (2.3%). Moreover there were 18 inconclusive or invalid urine test results. Thus the urine test provided misinformation or no information in 32 of 607, or 5.3%, of the total study population.  相似文献   
73.

Background  

Despite cost containment efforts, parenteral (IV) ciprofloxacin appears to be overutilized at Vancouver General Hospital. In November 2003, the Pharmacist-managed intravenous to oral (IV-PO) Dosage Form Conversion Service was implemented, enabling autonomous pharmacist-initiated dosage form conversion for ciprofloxacin. This study evaluates characteristics of ciprofloxacin use prior to and following implementation of this conversion service.  相似文献   
74.
Tooth sensitivity is a common clinical problem. This multi-center randomized clinical trial assessed the effectiveness and safety of topical diammine silver fluoride. From two sites (Lima and Cusco, Peru), 126 adults with at least one tooth sensitive to compressed air were randomly assigned to either the experimental treatment or sterile water, and pain was assessed by means of a 100-mm visual analogue scale at 24 hours and 7 days. The diammine silver fluoride reduced pain at 7 days at both sites. At the Lima site, the average change in pain scores between baseline and day 7 for the silver fluoride group was -35.8 (SD = 27.7) mm vs. 0.4 (SD = 16.2) mm for the control group (P < 0.001). In Cusco, the average change in pain scores for the silver fluoride group was -23.4 (SD = 21.0) mm and -5.5 (18.1) mm for the control group (P = 0.002). No tissue ulceration, white changes, or argyria was observed. A small number of participants in the silver fluoride group experienced a mild but transient increase in erythema in the gingiva near the tooth. No changes were observed in the Gingival Index. We concluded that diammine silver fluoride is a clinically effective and safe tooth desensitizer.  相似文献   
75.
76.
The metastatic invasion of cancer cells from primary tumors to distant ecological niches, rather than the primary tumors, is the cause of much cancer mortality [Zhang QB, et al. (2010) Int J Cancer 126:2534-2541; Chambers AF, Goss PE (2008) Breast Cancer Res 10:114]. Metastasis is a three-dimensional invasion process where cells spread from their site of origin and colonize distant microenvironmental niches. It is critical to be able to assess quantitatively the metastatic potential of cancer cells [Harma V, et al. (2010) PLoS ONE 5:e10431]. We have constructed a microfabricated chip with a three-dimensional topology consisting of lowlands and isolated square highlands (Tepuis), which stand hundreds of microns above the lowlands, in order to assess cancer cell metastatic potential as they invade the highlands. As a test case, the invasive ascents of the Tepui by highly metastatic PC-3 and noninvasive LNCaP prostate cancer cells were used. The vertical ascent by prostate cancer cells from the lowlands to the tops of the Tepui was imaged using confocal microscopy and used as a measure of the relative invasiveness. The less-metastatic cells (LNCaP) never populated all available tops, leaving about 15% of them unoccupied, whereas the more metastatic PC-3 cells occupied all available Tepuis. We argue that this distinct difference in invasiveness is due to contact inhibition.  相似文献   
77.
HIV p24 antigenaemia and virus detection in cultures of peripheral blood lymphocytes were examined in 16 of 18 haemophiliacs infected with HIV by a single batch of Scottish National Blood Transfusion Service factor VIII concentrate. Six (38%) had p24 antigenaemia and 11 (69%) had positive lymphocyte cultures. All seven patients with serious HIV disease (CDC group IV) had positive lymphocyte cultures whereas four (57%) had p24 antigenaemia. Four of nine (44%) patients with asymptomatic HIV disease (CDC groups II and III) had positive cultures and two (22%) had p24 antigenaemia. Twenty-eight of 36 samples from the symptomatic group were HIV culture positive compared with nine of 30 samples from the asymptomatic group (P less than 0.001). None of 14 antibody negative haemophiliacs who also received the implicated batch of factor VIII had p24 antigenaemia or positive HIV cultures. The ability to detect HIV in cultured lymphocytes correlates with the clinical severity of HIV disease in this cohort.  相似文献   
78.
PURPOSE: To analyze the clinical performance of adhesives with various solvents for restoration of non-carious cervical lesions. METHODS: The patient pool consisted of a total of 57 patients and 171 teeth (3 teeth per patient), with one non-carious cervical lesion per tooth. For each patient, one tooth was restored with a water-based, two-bottle adhesive (Scotchbond Multi-Purpose - SM), and another tooth with an ethanol-based, one-bottle adhesive (Single Bond - SB), and the other tooth with a solvent-free, one-bottle adhesive (One Coat Bond - OCB), all with resin-based composites (Silux Plus or Synergy). Restorations were assessed by retention, marginal integrity, margin discoloration and air sensitivity, according to modified USPHS criteria. The evaluations were performed at baseline, 6 months and 12 months after initial placement. RESULTS: The retention rates at 12 months were 98% for the SM adhesive, 91% for the SB adhesive, and 93% for the OCB adhesive. The differences in retention rates were not statistically significant, with 94% restorations retained overall. Measures of marginal integrity, marginal discoloration and sensitivity also had no statistically significant differences between the three adhesives. Overall, for the restorations still retained after 12 months, 80% had non/slightly detectable margins, 80% had no marginal discoloration and 90% had none/mild sensitivity. All three adhesives performed comparably with excellent outcomes after a 12-month period, with no significant differences between the water-based, ethanol-based and solvent-free adhesives, nor between the one-and two-bottle systems. Retention rate was high, air sensitivity was markedly reduced, and marginal integrity was good. Although superficial marginal discoloration was notable, no deep staining was evident. Certain lesion, tooth and patient characteristics may predispose restorations to retention failure.  相似文献   
79.
Leonard  JP; Quinto  CM; Kozitza  MK; Neben  TY; Goldman  SJ 《Blood》1994,83(6):1499-1506
Interleukin-11 (IL-11) is a novel multifunctional hematopoietic cytokine capable of stimulating cells of the myeloid, lymphoid, erythroid, and megakaryocytic lineages in vitro. We have tested the pleiotropic properties of this cytokine on the hematopoietic recovery of mice after a combined regimen of sublethal irradiation and carboplatin administration. This regimen results in severe myelosuppression, characterized by a prolonged period of thrombocytopenia and severe anemia. Administration of recombinant human IL-11 (rhIL-11; 250 micrograms/kg/d) had multilineage effects on bone marrow and spleen hematopoietic activity, increasing the number of megakaryocyte, erythroid, granulocyte, and macrophage progenitors compared with the vehicle-treated controls. This was reflected in the peripheral circulation by a reduction of both the platelet and hematocrit nadirs and a significantly reduced period of thrombocytopenia and anemia in the rhIL-11-treated mice. The results from this study support the broad spectrum of biologic activities that have been attributed to rhIL-11 in vitro and suggest that this cytokine may be an effective agent in the treatment of myelosuppression associated with cancer chemotherapy and bone marrow transplantation.  相似文献   
80.
Using a double polymerase chain reaction a method was devised for detecting and subtyping hepatitis B virus DNA in serum samples. Primers from the S-gene were selected from the sequence analyses of five HBV HBsAg subtypes, to amplify HBV DNA and subtype for y specific DNA. Thirty-eight samples were subtyped for d and y determinants by radioimmunoprecipitation assay (RIPA) and the polymerase chain reaction (PCR). Subtyping by PCR and RIPA was in agreement in 100% of subtype y samples and 83.3% of subtype d, giving an overall correlation of 92.1%. As a third comparison, 12 amplified samples were digested by the restriction enzyme Sau 3A, which differentiates between subtypes y and d. The digest results agreed with PCR in 83.3% of the samples. In addition, we compared our standard phenol/chloroform extraction against a rapid one step method. The phenol/chloroform stage was found to be essential for the removal of nucleases and polymerase inhibitors present in sera.  相似文献   
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