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31.
The aim of this study was to present long-term results of sagittal osteotomy of the patella after Morscher. The study included 70 patients treated for patellar dysplasia with a postoperative follow-up from nine to 20 years. There were 59 females and 11 males with an average age of 21 years at the time of operation. Results were evaluated for the entire group of 70 patients and then presented separately for the 30 patients in whom sagittal osteotomy of the patella was performed as a single procedure and 40 patients in whom, in addition to sagittal osteotomy of the patella, medialisation and ventralisation or distalisation of the tibial tuberosity were also performed. The mean value of the Wiberg patellar angle was 112 degrees preoperatively and 140 degrees postoperatively. In the whole group of patients excellent results were obtained in 24 (35%), good results in 30 (42%), fair results in 13 (19%) and poor results in three (4%) patients. In 30 patients with sagittal osteotomy as a single operation excellent results were obtained in 13 (43%), good results in 14 (47%) and fair results in three (10%) patients, while in the 40 patients with sagittal osteotomy and additional surgical procedures, 11 (27%) were excellent, 16 (40%) good, ten (25%) fair and three (8%) had poor results. Sagittal osteotomy of the patella after Morscher is an enrichment of the spectrum of the secondary-causal and preventive procedures for the treatment of patello-femoral disorders.  相似文献   
32.
Loss of blood-brain barrier (BBB) function may contribute to post-ischemic cerebral injury by yet unknown mechanisms. Ischemia is associated with anoxia, aglycemia and loss of flow (i.e. shearing forces). We tested the hypothesis that loss of shear stress alone does not acutely affect BBB function due to a protective cascade of mechanisms involving cytokines and nitric oxide (NO). To determine the relative contribution of shear stress on BBB integrity we used a dynamic in vitro BBB model based on co-culture of rat brain microvascular endothelial cells (RBMEC) and astrocytes. Trans-endothelial electrical resistance (TEER), IL-6 release and NO levels were measured from the lumenal and ablumenal compartments throughout the experiment. Flow-exposed RBMEC were challenged with 1 h of normoxic-normoglycemic flow cessation (NNFC) followed by reperfusion for 2 to 24 h. NNFC caused a progressive drop in nitric oxide production during flow cessation followed by a time-dependent increase in ablumenal IL-6 associated with a prolonged NO increase during reperfusion. The nitric oxide synthetase (NOS) inhibitor L-NAME (10 microM) abrogated all effects of NNFC, including changes in NO and cytokine production. BBB permeability did not increase during or after NNFC/reperfusion, but was increased by treatment with L-NAME or when the effects of IL-6 were blocked. Flow adapted RBMEC and astrocytes respond to NNFC/reperfusion by overproduction of IL-6, possibly secondary to increased production of NO during the reperfusion. Maintenance of BBB function during and following NNFC appears to depend on intact NO signaling and IL-6 release.  相似文献   
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An understanding of the physiology of the blood-brain barrier (BBB) is crucial when addressing complex issues such as drug delivery, pathogenesis of chronic neurological diseases and bio-defense. Rational central nervous system (CNS) drug design cannot entirely and exclusively rely upon the physicochemical properties of putative neurotherapeutics, since lipophilicity alone is a poor predictor for drug penetration into the CNS. This is particularly true for three large families of CNS drugs: antineoplastics, antivirals and anti-epileptics. For these drugs, in contrast to peripheral acting drugs (eg, antihistamines), negligible penetration across the BBB is preferable in order to avoid CNS side effects. Studies performed using small animals such as rodents cannot be directly extrapolated to human brain tissue, as demonstrated by both clinical and in vitro studies. Furthermore, most of the promising CNS drugs that proved effective in vitro have failed in clinical trials due to misleading predictive permeability data extrapolated from models that were not capable of fully reproducing the functional properties of the BBB in vivo. Therefore, a great effort has been made to develop new in vitro models able to reproduce the physiological, anatomical and functional characteristics of the BBB allowing for a better prediction of drug penetration across the BBB, and enabling the design of new pharmaceutical strategies to bypass the shielding of brain parenchyma. Herein we provide a detailed review and discussion of currently employed in vitro BBB models along with probable future developments.  相似文献   
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Hemorrhagic lymphatic malformation (formerly called hemolymphangioma) of the tongue is an uncommon malformation that may pose both functional and cosmetic problems for the patient. The challenge has been to find a conservative treatment with low morbidity and better results than those achieved with surgical excision, which has been the mainstay of therapy. We report a case of successful treatment of a hemorrhagic lymphatic malformation of the tongue with a variable-pulse 595-nm pulsed-dye laser (Vbeam; Candela Corp, Wayland, Mass). In this patient, pulsed-dye laser treatment of the hemorrhagic lymphatic malformation achieved satisfactory functional and cosmetic outcomes. Its use in superficial vascular lesions of the mucosa should be considered.  相似文献   
37.
Aim Our aim was to confirm that preoperative CA 125 serum level can be useful for discrimination between benign and malignant masses in the pelvis.Methods Preoperative CA 125 serum level was analyzed retrospectively in 121 patients who had surgery because of a malignant ovarian tumor and in 91 patients with benign masses in the pelvis. The cutoff serum level CA 125 between benign and malignant masses in the pelvis was 35 and 65 IU/ml.Results Of those patients with a malignant ovarian tumor, 65.3% had menopause whereas only 31.5% of those with a benign tumor did so. The average age of the patients with a malignant tumor was 54.2 years and of those with a benign tumor 46.8 years. The preoperative CA 125 serum level was higher than 35 IU/ml in 80.2% and higher than 65 IU/ml in 72.7% of all analyzed patients with a malignant tumor, whereas it was 23.9% and 9.8% respectively in patients with a benign mass. In early stage ovarian cancer disease (borderline stage, I/II) the preoperative CA 125 serum level was higher than 35 IU/ml in 67.8% and in 52.5% higher than 65 IU/ml. In advanced stages (III/IV), it was higher than 35 and 65 IU/ml in 96.1%. After therapy the CA 125 serum level dropped below 35 IU/ml in 70.8% and after three chemotherapy courses in 78.1%. A CA 125 level less than 35 IU/ml was achieved by therapy in 84.2% patients with an early stage disease (I/II) and in 62.1% in advanced stages (III/IV). The calculated sensitivity was 80.2% and negative 74.5% (CA 125 higher than 35 IU/ml) and 72.7%, 90.2%, 90.7%, 71.6% respectively (CA 125 higher than 65 IU/ml).Conclusion Preoperative determination of CA 125 is a very useful method to discriminate between benign and malignant masses in the pelvis.  相似文献   
38.

Background

S100β has been used in cardiac surgery to identify patients with postoperative neurologic complications. However, extracranial proteins may falsely elevate measurements of serum S100β;. Objectives of this study were (1) to quantify S100β levels in serum and pericardial cavity during coronary artery bypass grafting (CABG), and (2) to identify proteins recognized by standard immunodetection as S100β.

Methods

Systemic and pericardial cavity blood from 5 patients undergoing CABG were sampled before, during, and after cardiopulmonary bypass (CPB). A commercially available enzyme-linked immunosorbent assay (ELISA) kit was used to quantify S100β. Two-dimensional gel electrophoresis, Western blot, and mass spectroscopy were also performed to identify S100â and other proteins.

Results

Mean S100β levels measured by ELISA, systemic and pericardial cavity blood were (in ng · mL−1) 1.0 ± 0.46 and 111 ± 71 before CPB, 0.6 ± 0.11 and 113 ± 54 during CPB, and 1.7 ± 0.64 and 101 ± 42 after CPB, respectively. However, gel electrophoresis and Western blot analysis revealed proteins other than S100β to be present in the pericardial cavity giving a falsely elevated serum S100â levels measured by immunoassay. Mass spectroscopy of identified potential candidates revealed contaminants including haptoglobin I precursor, apolipoprotein A-1 precursor, complement factor B precursor, and complement C3 precursor.

Conclusions

S100β immunoassays are not specific for S100â and give a falsely elevated reading due to contaminants from the surgical field that cross react with the assay's antibody. This does not appear to be an issue in nonsurgical patients. Caution must be exerted when evaluating immunodetection results for low-abundance proteins under conditions where contamination of the sample is likely.  相似文献   
39.
Prognostic value of different factors in breast carcinoma   总被引:13,自引:0,他引:13  
INTRODUCTION: The aggressive biological behavior of invasive and metastatic cancer is considered to be the most insidious and life-threatening aspect for breast cancer patients. It is mostly the result of changes in many molecular characteristics of tumor cells, including alterations in the mechanisms controlling cell growth and proliferation. AIM: The aim of this retrospective study was to identify predictors of aggressive biological behavior and metastatic potential in breast carcinoma among a number of intrinsic biomarkers of tumor cells such as steroid receptors and oncogene and tumor suppressor gene products. METHODS: Routine formalin-fixed, paraffin-embedded tumor samples were used and sections were stained immunohistochemically with the DAKO Strept ABC method to determine the expression of estrogen receptors (ER), progesterone receptors (PgR), HER-2/neu, bcl-2, Ki-67, p53 and nm23 in 192 consecutive breast carcinoma patients. The results of the quantitative immunohistochemical assays were correlated with clinical and histological data such as patient age, overall survival, tumor size, axillary lymph node status, hystological type, tumor grade, Nottingham prognostic index (NPI) and therapeutic regimens. RESULTS: Univariate analysis revealed that survival was significantly longer for patients with small tumors (P = 0.007), lower tumor grade (P = 0.021), negative axillary lymph nodes (P = 0.002), presence of nm23 protein (P = 0.002), and for patients treated with adjuvant hormonal therapy (P = 0.010). In multivariate analysis the independent factors positively affecting survival were absence of axillary lymph node metastases (P = 0.002), nm23 expression (P = 0.009) and hormonal therapy (P = 0.050). Among patients with positive axillary nodes there was a significantly higher survival rate in patients with nm23 expression compared with nm23-negative patients (P < 0.001). CONCLUSION: Identification of a subset of node-positive breast cancer patients with a more favorable prognosis according to nm23 expression might be clinically useful.  相似文献   
40.
It is widely accepted that vascular mechanisms are involved in the genesis of many neurological disorders. In particular, blood-brain barrier (BBB) dysfunction has been related to the severity of Alzheimer's disease, encephalopathy due to meningitis, multiple sclerosis, HIV-associated encephalopathy, epilepsy, gliomas and metastatic brain tumors. The BBB may constitute an important therapeutic target to protect neurons after CNS diseases. Both in vivo and in vitro, the functional phenotype of vascular endothelium is dynamically responsive to circulating cytokines, growth factors and puslatile blood flow (shear stress). Shear stress can play a critical role in vascular homeostasis and pathophysiology; it is a major regulator of remodeling in developed blood vessels and in blood vessels affected by atherosclerotic lesions. The physiological fluid mechanic stimulus, shear stress, could be considered to be an important 'differentiative' stimulus capable of modulating endothelial phenotype in vivo. Endothelial cells undergo cell cycle arrest after exposure to physiological levels of shear stress. As for mature endothelial cells, in which flow mediated shear stress may play a role in the induction, progression and/or prevention of atherosclerosis by changing their function, stress may play a role in endothelial cell differentiation from hemopoietic stem cells and/or from embryonic stem cells. Stem cells may be used to repair vascular damage, including loss of EC, due to a variety of diseases (e.g. myocardial neovascularization by adult bone marrow derived angioblasts). In the brain, it was proposed that neuron-producing stem cells may be used to treat Alzheimer's disease, paralysis, etc. Surprisingly, very few investigators are exploring the use of endothelial precursors to revert or prevent cerebrovascular disease. This review summarizes the most recent data related to cerebral vasculature as a therapeutic target for neurological disorders and the role of shear stress in blood-brain barrier homeostasis and pathophysiology.  相似文献   
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