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Lymphatic infiltration is a well known phenomenon in different tumors including endocrine malignancies. However, little is known about the role of antigen-presenting cells and T cell activation in this context. The aim of our study was to investigate the quantity and function of CD14+/CD56+ monocytes in tumor patients including endocrine malignancies. First, these cells were characterized in peripheral blood of endocrine and non-endocrine cancer patients as well as in tumor tissue samples. Cancer patients had in mean 3.7 times more CD14+/CD56+ monocytes in the peripheral blood compared to healthy controls (p≤0.0001), while the highest frequencies were seen in patients with heavy tumor load. Importantly, these cells additionally expressed several NK cell markers. A proof of CD14+/CD56+ infiltrations into papillary thyroid carcinoma was shown by immunohistochemical analyses. Functional analyses revealed an apoptosis inducing capacity in vitro after IFN-α re-stimulation. Our data indicate the importance of tumor-lysing monocytes in antitumor immunity.  相似文献   
144.
Background and aimsPatients with chronic renal failure, especially those treated with haemodialysis, have an increased risk of developing atherosclerotic vascular disease probably as a result of enhanced oxidative stress. The human cell membrane possesses electron transfer systems which protect against extracellular pro-oxidant challenge. We evaluated (1) the erythrocyte velocity of ferricyanide reduction (RBC vfcy) in 25 uraemic patients (aged 25–71 years; 14 males), (2) the changes induced by a single haemodialysis session and (3) biomarkers of oxidative stress.Methods and resultsBefore and after a mid-week dialysis session, we measured RBC vfcy, erythrocyte glutathione (RBC GSH), plasma and red cell membrane malondialdehyde (P and RBC MDA), plasma sulphydryl groups (P SH), plasma vitamin C levels and haemolysis percentage.Pre-dialysis RBC GSH (0.68 ± 0.13 vs 0.80 ± 0.13 mg/mL, p < 0.01), P SH (266 ± 74 vs 406 ± 78 μmol/L, p < 0.01) and plasma vitamin C (7.0 ± 5.1 vs 21.5 ± 8.5 mg/L, p < 0.001) were lower than in 25 age-sex-matched healthy controls; P MDA (1.57 ± 0.52 vs 0.54 ± 0.29 nmol/mL, p < 0.001), RBC MDA (0.42 ± 0.13 vs 0.34 ± 0.16 nmol/mL, p < 0.05) and haemolysis (1.2 ± 0.3 vs 0.7 ± 0.3%, p < 0.001) were increased. Baseline RBC vfcy did not differ from normals (13.1 ± 5.2 vs 12.9 ± 3.2 mmol/mL/h). Following dialysis, RBC vfcy (to 8.9 ± 4.5 mmol/mL/h, p < 0.001) decreased, as well as P MDA, RBC MDA and plasma vitamin C (to 2.5 ± 1.4 mg/L, p < 0.001), whereas P SH groups increased (to 413 ± 99 μmol/L, p < 0.001); haemolysis percentage remained high. RBC vfcy values were correlated to RBC GSH and vitamin C levels.ConclusionsUraemic patients showed signs of oxidative stress. Pre-dialysis RBC vfcy is maintained in the normal range on account of a reduced intracellular content of GSH and in spite of low plasma ascorbate. A single haemodialysis treatment reduced biomarkers of protein and lipid oxidation but markedly impaired transmembrane electron transfer, which could be explained by acute depletion of electron donors.  相似文献   
145.
OBJECTIVE: Many patients with medullary thyroid carcinomas (MTC) have reoperative surgery in different hospitals, which makes their follow-up difficult. To comprehend these complex courses and to find relevant prognostic factors we report a 20-year single center experience of 289 patients with MTC or precursor C-cell-hyperplasias. PATIENTS AND METHODS: Between April 1986 and May 2006, 289 consecutive patients with MTC or MEN2 gene carriers were treated at the Department of Surgery at the University Hospital Düsseldorf. Tumor stages were documented according to the classification of the International Union against Cancer 5th edition, 1997 (Schott. Endocr Relat Cancer. 2006;13:779-795). A system to easily comprehend operative procedures is suggested. RESULTS: There were 159 female and 130 male patients (f/m ratio 1.22). Mean age at time of diagnosis was 32 years (4-77) in the familial cases and 53 years (23-84) years in the sporadic cases. Sixty-six patients (23%) had multifocal disease. Twelve MEN2-patients had only C-cell-hyperplasia (pT0). Tumor stage was pT1 in 86 patients, pT2 in 106 patients, pT3 in 25 patients, pT4 in 52 patients and unclear in 8 patients. In the 289 patients 648 operations were performed. One hundred seventy patients had more than 1 operation (59%). Ninety-nine patients (34%) are calcitonin-negative and 91 patients (31%) live with elevated calcitonin. Median follow-up time of the surviving 211 patients was 8.9 years (range, 0.3-30.7 years). The 5- and 10-year survival of all tumor patients was 86% and 68%, respectively. CONCLUSION: The chance to achieve biochemical cure in MTC is clearly dependent on the primary tumor size. The chance for long-term biochemical cure in a pT4-tumor is almost nil even after multiple and extended reoperations, whereas a pT1 tumor can be cured in up to 67% of the patients. Long-term survival, however, can be achieved even in pT4 tumor patients in almost 50%.  相似文献   
146.
BACKGROUND: High calcitonin (CT) serum levels suggest metastatic spread in medullary thyroid carcinoma (MTC) after thyroidectomy. In limited disease stages, however, morphological investigations including ultrasound, magnetic resonance imaging (MRI) and 18F-FDG positron emission tomography ([18F]FDG-PET) may often fail to identify exact tumour sites. OBJECTIVE: The aim of the present study was to establish an improved strategy to identify small cervical tumours by combining pentagastrin stimulation with bilateral cervical intravenous CT sampling followed by high-resolution ultrasound. DESIGN AND PATIENTS: Six MTC patients were examined, of whom five patients already had bilateral neck dissection. Five patients had sporadic MTC, and one patient suffered from MEN2a. RESULTS: Retrospective analysis of all patients revealed a highly sensitive positive correlation between an early calcitonin peak (20-40 s after pentagastrin injection) and site of cervical tumour affection. Postinterventional ultrasound examination of the affected regions of the neck revealed suspicious presence; in some cases small lymph nodes of less than 1 cm in size were then surgically excised. On histology, small tumours could be identified in four patients. Postsurgical examination revealed a clear decline of basal serum calcitonin levels in four patients (between -41% and -100%). In two patients CT normalized to baseline levels (< 10 pg/ml) and in another two patients CT rendered to near normal (14 and 17 pg/ml). CONCLUSION: Pentagastrin stimulation-based intravenous catheter sampling may be beneficial in the diagnostic work-up of MTC after thyroidectomy. Our data show that an early calcitonin peak (20-40 s after administration of pentagastrin) helps to identify tumour-affected regions.  相似文献   
147.
Evidence exists that left ventricular function is impaired in chronic uremic patients. During hemodialysis (HD) treatment, myocardium undergoes electrolyte, hemodynamic and neuro-humoral stress; however, data about the acute changes on ventricular function are controversial. Aim of the present study was to evaluate the effect of a single hemodialysis session on left ventricular (LV) systolic and diastolic function using pulsed tissue Doppler imaging (TDI) sampled by echocardiography. The study group included 20 uremic patients (17 males, aged 51+/-13 yrs) on maintenance HD, free from clinically overt cardiac dysfunction who underwent echocardiography with pulsed TDI 30 min prior and 30 min after a HD session. TDI was performed by placing the sample volume in the center of the basal lateral segment and the basal interventricular septum in the apical four-chamber view. Myocardial systolic wave (S(m)) and early (E(m)) and atrial (A(m)) diastolic waves were measured. On standard sonography examination, no significant changes in LV systolic function parameters were observed after HD, but the indices for LV diastolic function deteriorated significantly (peak E, 75.4+/-11.2 vs. 58.8+/-12.5 cm/s, P<0.01; E/A ratio, 1.0+/-0.3 vs. 0.8+/-0.2, P<0.01). However, regarding TDI measures following HD, the patients exhibited a lower S(m) peak (septum: 7.6+/-1.1 vs. 5.9+/-0.8 cm/s; lateral wall: 7.7+/-1.7 vs. 6.8+/-1.2 cm/s, P<0.001), a lower E(m) peak (septum: 8.3+/-1.6 vs. 6.3+/-1.7 cm/s; lateral wall: 10.2+/-2.4 vs. 7.1+/-1.9 cm/s, P<0.001), and a reduced E(m)/A(m) ratio (septum: 1.0+/-0.4 vs. 0.7+/-0.2; lateral wall: 1.2+/-0.5 vs. 0.7+/-0.2, P<0.001, respectively), as compared to pre-HD parameters. Of interest, peak E(m), and E(m)/A(m) ratio of the lateral wall were negatively related to ultrafiltration rate (r = -0.60, P<0.05 and -0.69, P<0.01, respectively). Our data indicate that a single hemodialysis session is associated with acute deterioration of diastolic and systolic parameters of myocardial function, as assessed by TDI. These reversible changes could be considered as a cardiac stunning that seems to be related to the ultrafiltration rate and then to the interdialysis weight gain. These findings suggest that low ultrafiltration volume and/or limited interdialytic weight gain are cardioprotective measures in hemodialysis patients.  相似文献   
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