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251.
In geometrical terms, tumour vascularity is an exemplary anatomical system that irregularly fills a three-dimensional Euclidean space. This physical characteristic and the highly variable shapes of the vessels lead to considerable spatial and temporal heterogeneity in the delivery of oxygen, nutrients and drugs, and the removal of metabolites. Although these biological characteristics are well known, quantitative analyses of newly formed vessels in two-dimensional histological sections still fail to view their architecture as a non-Euclidean geometrical entity, thus leading to errors in visual interpretation and discordant results from different laboratories concerning the same tumour. We here review the literature concerning microvessel density estimates (a Euclidean-based approach quantifying vascularity in normal and neoplastic pituitary tissues) and compare the results. We also discuss the limitations of Euclidean quantitative analyses of vascularity and the helpfulness of a fractal geometry-based approach as a better means of quantifying normal and neoplastic pituitary microvasculature.  相似文献   
252.
OBJECTIVES: The aim of the study was the detection, quantification and correlation of cell-free fetal (cff) DNA in maternal urine and plasma in normal and complicated pregnancies during the third trimester. METHODS: One hundred and fifty-one urine and plasma samples obtained from 96 women carrying male fetuses, and 55 carrying female fetuses were collected and analyzed for cff-DNA using fluorescent PCR and quantitative real-time PCR. DNA was extracted from 1 mL maternal urine and analyzed with two different primer sets (SRY and DYS-14). The concentrations of cff and total DNA in maternal plasma were correlated with maternal and obstetric parameters using appropriate correlation analyses. RESULTS: Y-chromosome-specific sequences were detected in 31 of 96 (32.3%) urine samples collected from women pregnant with male fetuses using DYS-14 and in 6 of 96 (6.3%) urine samples using SRY as primers using real-time PCR. All 96 plasma samples obtained from women carrying male fetuses were positive for cff-DNA using real-time PCR. Cff-DNA exhibited a correlation with gestational age (R = 0.244; P = 0.018) and an inverse correlation with the latency between blood collection and birth (R = - 0.218; P = 0.036). Total DNA showed a correlation with placental weight (R = 0.182; P = 0.034) and pregnancy-associated complications (R = 0.280; P < 0.001). CONCLUSION: Our data confirm that cff-DNA is cleared by the kidneys in detectable amounts, but due to its low concentration or problematic detection in maternal urine this source seems inappropriate for noninvasive prenatal diagnosis.  相似文献   
253.
Aims: A novel version of the tumour–node–metastasis (TNM) classification system for renal cell carcinoma (RCC) was introduced in 2010, although the prognostic significance with regard to different histological subtypes has not been explored. Therefore, the aim of our study was to compare the predictive ability of the 2002 and 2010 versions of the TNM classification system for clear cell and papillary RCC. Methods and results: Data from 2263 consecutive clear cell and 309 papillary RCC patients, operated at a single tertiary academic centre, were evaluated. According to TNM 2010, statistically significant differences for cancer‐specific survival (CSS) were observed for pT1a versus pT1b (P < 0.001) and pT3a versus pT3b (P < 0.004) in clear cell RCC; and pT1b versus pT2a (P = 0.002) and pT3b versus pT3c (P = 0.046) in papillary RCC. The c‐index for CSS in clear cell RCC was 0.74 and 0.73, and in papillary RCC 0.79 and 0.78, for the 2002 and 2010 versions of the TNM classification system, respectively. Conclusions: According to our data, the predictive ability of the 2010 version of the TNM classification system regarding CSS is not superior to the 2002 version, either in clear cell or in papillary RCC.  相似文献   
254.
Neuronal nitric oxide synthase (nNOS)-derived nitric oxide (NO) plays a major role in the neural control of circulation and in many cardiovascular diseases. However, the exact mechanism of how NO regulates these processes is still not fully understood. This study was designed to determine the possible sources of nitrergic nerve fibres supplying the heart attempting to imply their role in the cardiac neural control. Sections of medulla oblongata, vagal nerve, its rootlets and nodose ganglia, vagal cardiac branches, Th1-Th5 spinal cord segments, dorsal root ganglia of C8-Th5 spinal nerves, and stellate ganglia from 28 Wistar rats were examined applying double immunohistochemical staining for nNOS combined with choline acetyltransferase (ChAT), peripherin, substance P, calcitonin gene-related peptide, tyrosine hydroxylase or myelin basic protein. Our findings show that the most abundant population of purely nNOS-immunoreactive (IR) neuronal somata (NS) was observed in the nodose ganglia (37.4 ± 1.3%). A high number of nitrergic NFs spread along the vagal nerve and entered its cardiac branches. All nitrergic neuronal somata (NS) in the nucleus ambiguus were simultaneously immunoreactive (IR) to ChAT and composed only a small subset of neurons (6%). In the dorsal nucleus of vagal nerve, biphenotypic nNOS-IR/ChAT-IR neurons composed 7.0 ± 1.0%, while small purely nNOS-IR neurons were scarce. Nitrergic NS were plentifully distributed within the nuclei of solitary tract. In the examined dorsal root and stellate ganglia, a few nitrergic NS were sporadically present. The majority of sympathetic NS in the intermediolateral nucleus were simultaneously immunoreactive for nNOS and ChAT. In conclusion, an abundant population of nitrergic NS in the nodose ganglion implies that neuronal NO is involved in afferent cardiac innervation. Nevertheless, nNOS-IR neurons identified within vagal nuclei may play a role in the transmission of preganglionic parasympathetic nerve impulses.  相似文献   
255.

BACKGROUND:

A limited number of studies have used Tissue Doppler Imaging (TDI) to evaluate the effect of statin therapy on left ventricular dysfunction in patients with chronic heart failure. In this work, we aimed to determine whether statin administration influenced prognosis, inflammatory activation and myocardial performance evaluated by Tissue Doppler Imaging in subjects enrolled in the Daunia Heart Failure Registry, a local registry of patients with chronic heart failure.

METHODS:

This study retrospectively analyzed 353 consecutive outpatients with chronic heart failure (mean follow-up 384 days), based on whether statin therapy was used. In all patients, several Tissue Doppler Imaging parameters were measured; circulating levels of interleukin (IL)-6, IL-10 and C-reactive protein were also assayed.

RESULTS:

Statin administration in 128 subjects with ischemic heart disease was associated with a lower incidence of adverse events (rehospitalization for HF 15% vs. 46%, p<0.001; ventricular arrhythmias 5% vs. 21%, p<0.01; cardiac death 1% vs. 8%, p<0.05), lower circulating levels of IL-6 (p<0.05) and IL-10 (p<0.01), lower rates of chronic heart failure (p<0.001) and better Tissue Doppler Imaging performance (E/E'' ratio 12.82±5.42 vs. 19.85±9.14, p<0.001; ET: 260.62±44.16 vs. 227.11±37.58 ms, p<0.05; TP: 176.79±49.93 vs. 136.7±37.78 ms, p<0.05 and St: 352.35±43.17 vs. 310.67±66.46±37.78 ms, p<0.05).

CONCLUSIONS:

Chronic ischemic heart failure outpatients undergoing statin treatment had fewer readmissions for adverse events, blunted inflammatory activation and improved left ventricular performance assessed by Tissue Doppler Imaging.  相似文献   
256.
    
Guidelines advocate for the use of single-dose prophylaxis in open reduction internal fixation (ORIF) procedures. The presence of local (institutional) guidelines may assist in the uptake of evidence-based recommendations.  相似文献   
257.
258.
Creutzfeldt‐Jakob disease (CJD) is a rare rapidly progressive fatal neurodegenerative disease. Neuroleptic malignant syndrome (NMS) is a complication of antipsychotic medications which may be used to treat neuropsychiatric symptoms of CJD. We present a case of a 51‐year‐ old woman with CJD who developed NMS after being prescribed quetiapine.  相似文献   
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