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排序方式: 共有331条查询结果,搜索用时 15 毫秒
81.
82.
Narayanan SS Goel V Sarin R Jalali R Shrivastava SK Deshpande DD Dinshaw KA 《International journal of radiation oncology, biology, physics》2003,56(3):690-696
PURPOSE: To evaluate the variability in catheter length, geometry, and dosimetric parameters of radical intraoperative high-dose-rate breasts implant during 7-11 days. METHODS AND MATERIALS: Simulator X-rays, CT scans, and dosimetric studies were repeated on alternate days in 14 consecutive patients treated with radical intraoperative two- or three-plane nylon catheter high-dose-rate implant (34 Gy in 10 fractions within 5 days). RESULTS: Significant variation was found in catheter length, but no major change was noted in implant geometry, homogeneity, or inhomogeneity indexes. A variation in length of >5 mm in one or more catheters was seen in all patients and >10 mm in 11 patients at any time during the implant. Of the 171 catheters in 14 patients, 100 (58%) and 38 (22%) showed a variation of >5 mm or >10 mm, respectively. The variation of >10 mm was reduced from 32% of catheters in the first 5 patients to 17% in the subsequent 9 patients (p = 0.028). Rigid catheter fixation might reduce length variation but may cause skin necrosis if the expanding cavity indents the skin for a long period against the fixation device. A dose homogeneity index of 0.90 (range 0.85-0.92) and dose nonuniformity ratio of 0.20 (range 0.12-0.25) were satisfactory. CONCLUSION: The catheter fixation and exit catheter length should be measured daily and if the implant is in situ for more than a few days, orthogonal X-rays and, if indicated, dosimetry should be repeated at least once. 相似文献
83.
Rosenberg L Stephenson WP Rao RS Palmer JR Strom BL Shapiro S 《Cancer causes & control : CCC》1998,9(6):611-614
Objectives: Renal cell cancer has been associated with hypertension or with drugs to treat it in several studies. We assessed whether the association is explained by more frequent detection of early renal cell cancer among persons being treated for hypertension.Methods: The data were collected in our Case-Control Surveillance Study, in which patients aged 20 to 69 years were interviewed in hospitals in Baltimore, Boston, New York, and Philadelphia during 1976-1996. We compared 134 incident cases of renal cell cancer who were being treated with drugs for hypertension to 193 untreated cases with respect to the route to diagnosis and the stage.Results: The relative risk estimate for having been diagnosed incidentally during a routine examination or workup for another condition, relative to having been diagnosed because of symptoms of renal cell cancer, was 1.3 (95 percent confidence interval, 0.7-2.5). The estimate for diagnosis at stage I or II relative to stage III or IV was 1.2 (0.7-2.1).Conclusion: In Case-Control Surveillance Study data, the relative risk estimate for renal cancer among users of various classes of antihypertensive drugs is 1.8 or 1.9. The present results suggest that this association can, at most, be explained only partially by the selective diagnosis of renal cell cancer among persons being treated for hypertension. 相似文献
84.
Conclusion Ours is probably the youngest child with C.S.S. reported in literature who is still having bronchial asthma after recovery
from the vasculitis phase. 相似文献
85.
Subhash Chand Catherine DeMarino Austin Gowen Maria Cowen Sarah Al-Sharif Fatah Kashanchi Sowmya V. Yelamanchili 《Viruses》2022,14(3)
Despite the success of combinational antiretroviral therapy (cART), the high pervasiveness of human immunodeficiency virus-1 (HIV)-associated neurocognitive disorders (HAND) poses a significant challenge for society. Methamphetamine (meth) and related amphetamine compounds, which are potent psychostimulants, are among the most commonly used illicit drugs. Intriguingly, HIV-infected individuals who are meth users have a comparatively higher rate of neuropsychological impairment and exhibit a higher viral load in the brain than infected individuals who do not abuse meth. Effectively, all cell types secrete nano-sized lipid membrane vesicles, referred to as extracellular vesicles (EVs) that can function as intercellular communication to modulate the physiology and pathology of the cells. This study shows that meth treatments on chronically HIV-infected promonocytic U1 cells induce the release of EVs that promote cellular clustering and syncytia formation, a phenomenon that facilitates HIV pathogenesis. Our analysis also revealed that meth exposure increased intercellular adhesion molecule-1 (ICAM-1) and HIV-Nef protein expression in both large (10 K) and small (100 K) EVs. Further, when meth EVs are applied to uninfected naïve monocyte-derived macrophages (MDMs), we saw a significant increase in cell clustering and syncytia formation. Furthermore, treatment of MDMs with antibodies against ICAM-1 and its receptor, lymphocyte function-associated antigen 1 (LFA1), substantially blocked syncytia formation, and consequently reduced the number of multinucleated cells. In summary, our findings reveal that meth exacerbates HIV pathogenesis in the brain through release of proadhesive EVs, promoting syncytia formation and thereby aiding in the progression of HIV infection in uninfected cells. 相似文献
86.
Jeffrey S. Ross M.D. Santhamma Kurian M.D. 《The American journal of gastroenterology》1985,80(3):188-194
Hypoglycemia is a frequent paraneoplastic complication of hepatocellular carcinoma occurring in up to 30% of cases of this neoplasm. The clear cell carcinoma, a notable histological subtype of hepatocellular carcinoma, however, has been associated with hypoglycemia in only two previously reported patients from Japan. We report herein the first American case of clear cell hepatocellular carcinoma with severe hypoglycemia. The patient also suffered from hypercholesterolemia and erythrocytosis. Fine needle aspiration cytology, conventional histopathology, and immunohistochemical studies of this neoplasm are described. Possible explanations for the clear cell appearance and a comparison of the clinical and morphological features of clear cell and nonclear cell hepatocellular carcinoma is made. Potential pathophysiological mechanisms for the paraneoplastic complications of hypoglycemia, hypercholesterolemia, and erythrocytosis are discussed. 相似文献
87.
88.
Ran D Goldman Sowmya Balasubramanian Paul Wales Sharon E Mace 《The journal of pain》2005,6(10):650-655
Inguinal hernias become incarcerated in 10% to -15% of children and reduction of the hernia is an urgent painful procedure. No recommendations exist for analgesia during this procedure. We surveyed pediatric emergency physicians (PEP) and pediatric surgeons (PS) for their analgesia and sedation use during the reduction. The survey was mailed to 19 centers in North America. A total of 56% (185/331) surveys were completed by PEP and 56% (68/122) from PS. A total of 96.7% (245/253) of responders reported giving analgesia or sedation during reduction. PS were more likely to use intravenous drugs, try for a longer time, wait longer between trials, and conduct more trials compared to the PEP. Clinically related variables were more important for PEPs than PS for analgesia and sedation. System-related variables were more important by PS for admission. PERSPECTIVE: This survey shows significant variability between specialties in the drugs, route, and number of attempts during reduction of a painful incarcerated hernia in children. Development of a sedation and analgesia protocol may be useful in order to unify management of pain and discomfort during hernia reduction. 相似文献
89.
Theoretical computations have been done to obtain dose distributions in the paracervical and sagittal planes for various loadings of Cathetron applicators. Uterine catheters of various sizes and shapes and various loadings of ovoid catheters have been considered for the dosimetry. Experimental measurements have been made to verify the computed dose distributions. The computed dose distributions have also been compared with those of a conventional Manchester loading. Although the ratio of dose contribution to point A from vaginal sources to that from the uterine sources is found to be significantly different for Cathetron therapy from the conventional Manchester system, the isodose distributions in the paracervical plane are in good agreement. However, the differences in the isodose distributions in the sagittal plane indicates a higher dose to the rectal region for Cathetron therapy, which can be reduced by the use of rectal retractors. 相似文献
90.
Palmer JR Hatch EE Rosenberg CL Hartge P Kaufman RH Titus-Ernstoff L Noller KL Herbst AL Rao RS Troisi R Colton T Hoover RN 《Cancer causes & control : CCC》2002,13(8):753-758
BACKGROUND: A synthetic estrogen, diethylstilbestrol (DES), was widely prescribed to pregnant women during the 1950s and 1960s but was later discovered to be associated with an increased risk of clear-cell carcinoma of the vagina and cervix in female offspring. DES has not been linked to other cancers in female offspring, but studies of other prenatal factors such as twin gestation and pre-eclampsia have indicated that in-utero estrogen levels may influence breast cancer risk. We evaluated the relation of in-utero DES exposure to the risk of adult breast cancer.METHODS: A cohort of 4821 exposed women and 2095 unexposed women, most of whom were first identified in the mid-1970s, were followed by mailed questionnaires for an average of 19 years. Reported cancer outcomes were validated by medical record review. Breast cancer incidence in DES-exposed daughters was compared with cancer incidence in unexposed daughters with use of Poisson regression analysis, adjusting for year of birth, age at menarche, age at first birth, and number of births.FINDINGS: The rate ratio for incidence of invasive breast cancer in exposed versus unexposed women was 1.4 (95% confidence interval (CI) = 0.7–2.6). DES exposure was not associated with an increased risk of breast cancer in women under 40 years, but among women aged 40 and older the rate ratio was 2.5 (95% CI = 1.0–6.3). The rate ratio for the association of DES exposure with estrogen receptor-positive tumors was 1.9 (95% CI = 0.8–4.5).INTERPRETATION: While not statistically significant, the overall 40% excess risk, arising exclusively from the subset of estrogen receptor-positive cases, raises a concern calling for continued investigation. 相似文献