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排序方式: 共有1224条查询结果,搜索用时 15 毫秒
1.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
2.
Carroll J. Bellis 《ANZ journal of surgery》1994,64(5):295-296
Laparoscopic inguinal herniorrhaphy with or without application of mesh does not correct the basic problem. Unless the dense fascial and bony margins of the posterior inguinal canal wall are palpated under direct vision for suture of the mesh, fortification is not possible and recurrence is invited. The many neural structures cannot be seen with the laparoscope, and their stapling is a prominent hazard. The procedure should not be accepted or approved. 相似文献
3.
Morphological comparison of sperm in raw ejaculates and swim-ups showed that the swim-up process does not simply increase the proportion of 'normal' sperm. Rather, sperm of specific morphologies have characteristic grades of upward motility. 相似文献
4.
Gil Bellis Marie-Hélène Cazes Alain Parant Maryse Gaimard Cécile Travers Evelyne Le Roux Sophie Ravilly Gilles Rault 《Journal of cystic fibrosis》2007,6(3):179-186
BACKGROUND: In 1992 France set up a national cystic fibrosis observatory (Observatoire national de la mucoviscidose, ONM) to monitor the state of health of patients on an annual basis. Using the ONM data, this study estimates the main indicators for life expectancy and assesses the total number of cystic fibrosis patients. METHODS: The data for the years 1994 to 2003 are divided into 3-year periods. Life tables are drawn up for these periods, from which mean and median lengths of life are determined. Using the most recent life table, the number of births in 2003 and the incidence of the disease, the total population of patients can be estimated, assuming a stationary population. RESULTS: In 2001-2003, life expectancy at birth of patients registered with the ONM was 39.1 years and median length of life was 36.4 years. These results, substantially better than those of 1994-1996, are linked to improved conditions of patient inclusion in the ONM database, to improvements in their healthcare, but also to the limitations of the life tables. Based on the 2003 data, the total theoretical number of patients is 6490, and coverage by the ONM database is thus 63.2%. CONCLUSIONS: These provisional results demonstrate the need to convert the ONM observatory into a registry providing exhaustive coverage of all patients. 相似文献
5.
6.
Emilio Benfenati Pierluigi Farina Tina Colombo Gianluca De Bellis Mauro Valerio Capodiferro Maurizio D'Incalci 《Cancer chemotherapy and pharmacology》1989,24(6):354-358
Summary The pharmacokinetics of the anticancer agent p-(3,3-dimethyl-1-triazeno) benzoic acid (pCOOH-DMT), a drug now in phase I clinical trial in Europe, was investigated in C57 Bl female mice with M5076 reticulum-cell sarcoma that were treated i.v. with 200 mg/kg pCOOH-DMT. The drug disappeared from plasma with a terminal half-life of about 2.5 h. Plasma clearance was approximately 6 ml/min per kg. Distribution studies showed some differences in drug levels in different tissues. The highest levels were found in the tumor, liver, kidney and lung; lower levels were found in the spleen and gut, and the lowest, in the brain. The N-desmethyl derivative of pCOOH-DMT was not detectable in plasma or tissues of mice treated with the drug. Therefore, the previous evidence of low N-demethylation of pCOOH-DMT was confirmed. pCOOH-DMT glucuronide was identified by mass spectrometry and quantified by high-performance liquid chromatography (HPLC) in plasma, tissues and urine samples. pCOOH-DMT glucuronide appears to be the major urinary metabolite of pCOOH-DMT in mice. Another metabolite identified by mass spectrometry and quantified by HPLC in some tissues and urine was pCOOH-DMT glycinate.Abbreviations DTIlC
5-(3,3-dimethyl-l-triazeno)imidazole-4-carboxamide
- pCOOH-DMT
p-(3,3-dimethyl-l-triazeno)benzoic acid
- pCOOH-MMT
p-(3-methyl-l-triazeno)benzoic acid
- pCONH2-DMT
p-(3,3-dimethyl-l-triazeno)carboxamide
- BSTFA
N,O-bis(trimethylsilyl)trifluoroacetamide
- TMCS
trimethylchlorosilane
- TLC
thin-layer chromatography
- FAB
fast atom bombardment
- EI
electron impact
- M5
M5076 reticulum-cell sarcoma
- t1/2
beta-half-life
- C0
concentration time 0
- AUC
area under the concentration vs time curve
- Cl
total clearance
- V
volume of distribution 相似文献
7.
Capodicasa E Russano AM Ciurnella E De Bellis F Rossi R Scuteri A Biondi R 《Immunopharmacology and immunotoxicology》2000,22(4):671-683
Plasma levels of human polymorphonuclear elastase (PMN-E) are considered a marker of granulocyte activation and can potentially complement the peripheral neutrophil count in laboratory and pathophysiological settings. Neutrophilic leukocytosis is a well known effect of lithium therapy, but there is no information about the concomitant behaviour of PMN-E in these patients. The aim of this study was to evaluate both polymorphonuclear leukocyte count and plasma PMN-E levels in depression patients undergoing chronic lithium therapy. Absolute and differential leukocyte count in venous peripheral blood was determined by an automated method, and PMN-E evaluated by enzyme immunoassay. 39 patients (11 males, 28 females; mean age 43. +/- 6.02) with depression disorders were studied, during lithium carbonate therapy. Neutrophilia (neutrophil count > 7.500x10(9) cells per liter) was found in 7 (18%) patients and an increase in plasma PMN-E levels (PMN-E > 56 microg per liter ) in 6 (15%). No correlations were found between neutrophil count, plasma concentration of PMN-E, plasma level of lithium and duration of therapy. The results show that in these patients, not only the PMN count but also elastase levels can exceed the normal range. The absence of correlation between these two parameters suggests that the state of PMN activation is not linked to their number in peripheral blood. 相似文献
8.
A Bizzarro G Torino G Castello A De Bellis A Daponte A Fontana V A Paglionico 《Annales de biologie clinique》1987,45(4):437-439
Peripheral blood mononuclear cell populations in ten men, with idiopathic infertility with serum sperm agglutinating antibodies at a titre of 1/32, were evaluated. Mononuclear cells were enumerated using the monoclonal antibodies OKT3 (pan T cells), OKT4 (helper/inducer T cells), OKT8 (suppressor/cytotoxic T cells), Leu 7 (monocytes, null cells, and natural killer (NK) cells), OKIa (B cells, monocytes, null cells and activated T cells). Blood mononuclear cells with surface receptors for complement (B lymphocytes and a proportion of monocytes and null cells) were enumerated using a rosette test (EAC). The following abnormalities, compared to normal subjects, of blood mononuclear cell population were found: a decreased percentage of OKT3 (+) cells (p less than 0.01), a decreased percentage of OKT8 + cells (p less than 0.001) and increased OKT4/OKT8 ratio (p less than 0.001), an increased percentage of OKIAI cells (p less than 0.001). Levels of OKT4+ and Leu 7 cells and the percentage of EAC rosette forming cells were not significantly different from those in normal subjects. Regression analysis showed a significant correlation between the percentage of OKIAI cells and sperm agglutinating antibodies. After all that, significant correlation between humoral and cell-mediated immunity in patients with idiopathic infertility with antisperm autoantibodies, were observed. 相似文献
9.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献
10.
B D Cheson C C De Bellis G B Schumann J L Schumann 《American journal of clinical pathology》1985,83(4):421-425
The authors examined urine specimens from 30 patients with multiple myeloma (MM) to determine the usefulness of cytodiagnostic urinalysis in evaluating such patients. Nine patients had clinical evidence of renal failure. In six of these nine patients (67%), or 20% of all patients, the urine sediment contained unique "MM-casts." These were characterized by a waxy to granular matrix surrounded by reactive, syncytial, giant cells with occasional renal cells embedded in the cast matrix. These casts were not observed in urine specimens from patients with normal renal function. Renal biopsy in two patients with MM-casts confirmed that cytologic diagnosis of "MM-kidney." The patient groups with or without MM-casts were comparable with respect to age, sex, and clinical stage of disease. In contrast, those with MM-casts were more likely to have clinical evidence of renal disease (100% vs. 13%), Bence Jones proteinuria (100% vs. 35%), hypercalcemia (50% vs. 8%), and hyperuricemia (50% vs. 4%). The two groups could not be distinguished reliably by urine physicochemical determinations. However, there were marked differences in the frequency of microscopic abnormalities. All patients with MM-cast formation excreted other pathologic casts as well and had evidence of tubular injury, while five of six had evidence of ischemic necrosis. This compared with 17%, 13%, and 21%, respectively, of those without MM-casts. Thus, cytodiagnostic urinalysis is of value in distinguishing MM-kidney from the numerous other causes of renal failure in patients with MM. 相似文献