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41.
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We demonstrate a novel activation behavior of human leucocyte adhesion under physiological flow conditions in a microfabricated silicon array of channels with length scales similar to those of human capillaries. Vital nuclei stains and cell specific, flourochrome labeled antibodies reveal that the equilibrium distribution of stuck cells in the arrays displays a strong dependence on cell type and nuclear morphology, and there is eventual separation of the two cell types in the array. The distortion of the cells is the same as they experience in vivo and the response of the granulocytes is consistent with a model describing adhesion as a function of the distortion of the cell by its environment; in other words, activated adhesion. We propose that this complex non-random behavior is due to a deformation activated change in the cells relevant to observed in vivo behavior.  相似文献   
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The purpose of our study was to review and evaluate retrospectively the experience of an in-vitro fertilization (IVF) surrogate gestational programme in a tertiary care and academic centre. In a 15 year period from 1984 to 1999, a total of 180 cycles of IVF surrogate gestational pregnancy was started in 112 couples. On average, the women were 34.4 +/- 4.4 years of age, had 11.1 +/- 0.72 oocytes obtained per retrieval, 7.1 +/- 0.5 oocytes fertilized and 5. 8 +/- 0.4 embryos subsequently cleaved. Sixteen cycles (8.9%) were cancelled due to poor stimulation. Except for six cycles (3.3%) where there were no embryos available, an average of 3.2 +/- 0.1 embryos was transferred to each individual recipient. The overall pregnancy rate per cycle after IVF surrogacy was 24% (38 of 158), with a clinical pregnancy rate of 19% (30 of 158), and a live birth rate of 15.8% (25 of 158). When compared to patients who underwent a hysterectomy, individuals with congenital absence of the uterus had significantly more oocytes retrieved (P < 0.006), fertilized, cleaved and more embryos available for transfer despite being of comparable age. IVF surrogate gestation is an established, yet still controversial, approach to the care of infertile couples. Take-home baby rates are comparable to conventional IVF over the same 15 year span in our programme. Patients with congenital absence of the uterus responded to ovulation induction better than patients who underwent a hysterectomy, perhaps due in part to ovarian compromise from previous surgical procedures.  相似文献   
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Cytochemical methods were used to determine the ultrastructural distribution of antimonate precipitable cations, anionic complex carbohydrate, acid phosphatase, and peroxidase in blood basophils from patients with chronic myelocytic leukemia and markedly elevated basophil counts. The morphology of these basophils varied but was generally similar to that reported for normal basophils. Antimonate precipitable cations were sparse in specific granules but more abundant in extra-granular cytoplasm and in vesicular structures of many basophils and, although varying with the fixation method, were distributed atypically in nuclei in a pattern similar to that seen in mast cells. The dialyzed iron technique diffusely stained anionic complex carbohydrate in the specific granules of basophils, and high iron diamine staining disclosed a sulfated mucosubstance in these granules. Acid phosphatase and peroxidase were distributed in a pattern similar to that of the acid mucosubstance in the basophil granules, and their presence suggested a lysosomal function for these granules  相似文献   
45.
Pulmonary interstitial fibrosis, a well-known toxic effect of bleomycin therapy, usually presents radiographically as diffuse reticularity. The authors report an unusual case of biopsy-proven bleomycin toxicity that presented as pulmonary nodules mimicking metastatic tumor. The histologic findings resembled those seen in the diffuse form of toxicity but notably also included foci of bronchiolitis obliterans.  相似文献   
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The lateral chest radiograph contains a wealth of data on the status of the thoracic cage, pleura, heart, pericardium, bronchi, and upper abdomen. The appearances of slightly oblique projections deviating from the "true" lateral projection are reviewed. Careful attention to these common variations of projection is advocated.  相似文献   
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BackgroundThe prevalence of total joint arthroplasty (TJA) in the United States has drawn the attention of health care stakeholders. The payers have also used a variety of strategies to regulate the medical necessity of these procedures. The purpose of this study was to examine the level of evidence of the coverage policies being used by commercial payers in the United States.MethodsThe references of the coverage policies of four commercial insurance companies were reviewed for type of document, level of evidence, applicability to a TJA population, and success of nonoperative treatment in patients with severe degenerative joint disease.Results282 documents were reviewed. 45.8% were primary journal articles, 14.2% were level I or II, 41.2% were applicable to patients who were candidates for TJA, and 9.9% discussed the success of nonoperative treatment in patients who would be candidates for TJA.ConclusionMost of the references cited by commercial payers are of a lower level of scientific evidence and not applicable to patients considered to be candidates for TJA. This is relatively uniform across the reviewed payers. The dearth of high-quality literature cited by commercial payers reflects the lack of evidence and difficulty in conducting high level studies on the outcomes of nonoperative versus operative treatment for patients with severe, symptomatic osteoarthritis. Patients, surgeons, and payers would all benefit from such studies and we encourage professional societies to strive toward that end through multicenter collaboration.  相似文献   
50.
BackgroundEstablishing clear risk factors for complications such as urinary tract infection (UTI) after arthroplasty procedures helps guide clinical practice and provides more information to both surgeons and patients. This study aims to assess selected preoperative patient characteristics as risk factors for postoperative UTI after primary total hip and knee arthroplasties (THA and TKA).MethodsThis was a retrospective analysis using current procedural terminology codes to investigate the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database for patients who underwent THA or TKA from 2010 to 2017. Patients were classified for UTI by NSQIP guidelines. Patient samples with all possible covariates were included for multivariate logistic regression analysis and assessed for independent associations.ResultsIn a cohort of 983 identified patients (983 of 119,096; 0.83%): ages 57+ years, preoperative red blood cell (RBC) transfusion, perioperative RBC transfusion, bleeding disorders, operative time 110+ minutes, preoperative steroid use, diabetes, pulmonary comorbidities, body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after THA. In a cohort of 1503 identified patients (1503 of 189,327; 0.8%): ages 60+ years, preoperative RBC transfusion, perioperative RBC transfusion, anemia, platelets less than 150k, preoperative steroid use, diabetes, and body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after TKA. Male sex was associated with a decreased risk of UTI in both THA and TKA.ConclusionThis study provides novel evidence on risk factors associated with the development of UTI after THA or TKA. Clinicians should be aware of risk factors in the manifestation of postoperative UTI after primary THA or TKA procedures.  相似文献   
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