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51.
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Recurrent subependymoma of fourth ventricle with unusual atypical histological features: A case report 下载免费PDF全文
Subependymoma is a rare subtype of benign ependymal neoplasm with distinct histological features. Anaplastic transformation has not yet been reported in this tumor to date. We present here a very unusual case of a 62‐year‐old woman with recurrent subependymoma of the fourth ventricle with multiple atypical histological features. Histologically, the resected recurrent tumor showed characteristic small cell clusters and nests of ependymal cells with an interspersed gliofibrillary matrix as seen in a classic subependymoma. In addition, there were very unusual histological features, including multiple areas of necrosis, microvascular proliferation, thrombosed blood vessels, and scattered mitotic figures. No coexisting ependymoma component of higher World Health Organization (WHO) grade was present. Immunohistochemically, MIB‐1 labeling index was high, with up to 15% in the highest areas. Review of this patient's initial tumor, which was resected 6 years prior to recurrence, demonstrated features of a typical classic subependymoma without atypical features or a secondary tumor component. Subependymomas are known to be low‐grade tumors and are usually cured if completely excised. The tumor presented here is unique in that several atypical pathological features were found in an otherwise typical subependymoma. Our case may represent anaplastic transformation of subependymoma, although no such examples have been reported to date. 相似文献
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We have identified a population of normal mouse LN cells, termed LN lymphoid progenitor (LNLP), resembling common lymphoid progenitor (CLP) in the bone marrow. LNLPs lack lineage markers and express CD127, low levels of CD117 (c-Kit), and Sca-1, but lack fms-related tyrosine kinase 3. They efficiently differentiate in vitro into natural killer (NK) cells and T cells, but not mature B cells. LNLPs injected into nonirradiated lymphopenic mice that have no LN develop into mostly splenic T cells with low numbers of NK cells and B cells. When injected into irradiated mice, they generate NK cells and T cells, but not B cells, in the LN. By contrast, bone marrow CLPs develop into mostly B cells with very small numbers of T and NK cells in recipients' spleen and LN. LNLPs have NK and T-cell potentials, but little B-cell potential, and they can develop into NK cells within the LN of normal mice, but their contribution to the T-cell lineage is unknown. 相似文献
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Hiroshi Kinashi Yasuhiko Ito Masashi Mizuno Yasuhiro Suzuki Takeshi Terabayashi Fumiko Nagura Ryohei Hattori Yoshihisa Matsukawa Tomohiro Mizuno Yukihiro Noda Hayato Nishimura Ryosuke Nishio Shoichi Maruyama Enyu Imai Seiichi Matsuo Yoshifumi Takei 《Journal of the American Society of Nephrology : JASN》2013,24(10):1627-1642
Peritoneal fibrosis (PF) causes ultrafiltration failure (UFF) and is a complicating factor in long-term peritoneal dialysis. Lymphatic reabsorption also may contribute to UFF, but little is known about lymphangiogenesis in patients with UFF and peritonitis. We studied the role of the lymphangiogenesis mediator vascular endothelial growth factor-C (VEGF-C) in human dialysate effluents, peritoneal tissues, and peritoneal mesothelial cells (HPMCs). Dialysate VEGF-C concentration correlated positively with the dialysate-to-plasma ratio of creatinine (D/P Cr) and the dialysate TGF-β1 concentration. Peritoneal tissue from patients with UFF expressed higher levels of VEGF-C, lymphatic endothelial hyaluronan receptor-1 (LYVE-1), and podoplanin mRNA and contained more lymphatic vessels than tissue from patients without UFF. Furthermore, mesothelial cell and macrophage expression of VEGF-C increased in the peritoneal membranes of patients with UFF and peritonitis. In cultured mesothelial cells, TGF-β1 upregulated the expression of VEGF-C mRNA and protein, and this upregulation was suppressed by a TGF-β type I receptor (TGFβR-I) inhibitor. TGF-β1–induced upregulation of VEGF-C mRNA expression in cultured HPMCs correlated with the D/P Cr of the patient from whom the HPMCs were derived (P<0.001). Moreover, treatment with a TGFβR-I inhibitor suppressed the enhanced lymphangiogenesis and VEGF-C expression associated with fibrosis in a rat model of PF. These results suggest that lymphangiogenesis associates with fibrosis through the TGF-β–VEGF-C pathway.The decrease in ultrafiltration capacity that is associated with the high peritoneal solute transport that is observed after prolonged peritoneal dialysis (PD) treatment is a major reason for its discontinuation.1–4 Several studies have shown that a higher peritoneal solute transport rate is associated with reduced survival of PD patients.1,2,5 The characteristic features of chronic peritoneal damage in PD treatment are associated with submesothelial fibrosis and neoangiogenesis.6,7 Analyses of the surface peritoneum showed no significant changes in vessel density with duration of PD.6,8 In addition, the vessel density in patients with ultrafiltration failure (UFF) was significantly higher than the vessel density in normal individuals or non-PD patients, but it was not higher than the vessel density in patients undergoing PD.6 These findings suggest that factors other than increased vascular density may be involved in disease states associated with increased transport of peritoneal membranes. In addition, the relationship between peritoneal fibrosis and UFF remains obscure.Blood capillaries have a continuous basal lamina with tight interendothelial junctions and are supported by pericytes and smooth muscle cells. In contrast, lymphatic capillaries are thin-walled with a wide lumen and do not contain pericytes or basement membrane. The structures of lymphatic vessels are suitable for the removal of tissue fluid, cells, and macromolecules from the interstitium.9–11 If lymphangiogenesis develops in the peritoneal membrane, absorption of the PD fluid could be increased and lead to UFF. An increase in the number of lymphatic vessels has recently been reported in several disease conditions, including tumor metastasis,12–15 chronic respiratory inflammatory diseases,16–18 wound healing,19 and renal transplant rejection.20,21 We recently reported that lymphangiogenesis had developed in tubulointerstitial fibrosis of human renal biopsy specimens,22 and we also reported the mechanisms of lymphangiogenesis in rat unilateral ureteral obstruction models.23The lymphatic absorption rate, which is measured by the rate at which intraperitoneally administered radioactive serum albumin or macromolecule dextran 70 disappears, is significantly higher in patients with UFF, and lymphatic reabsorption is considered to be one of the causes of UFF.24–27 However, the results from these clinical approaches have been controversial.28,29 In addition, little is known about the pathology and the process of lymphangiogenesis in patients with UFF and peritonitis.In this study, we investigated lymphangiogenesis and the expression of vascular endothelial growth factor-C (VEGF-C), which is a potentially important mediator of lymphangiogenesis, in human peritoneal tissues, PD effluent, and peritoneal mesothelial cells. We also explored VEGF-C induction by TGF-β1 in the human mesothelial cell line (Met-5A) and cultured human peritoneal mesothelial cells (HPMCs) from the spent PD effluent of patients with varying rates of peritoneal transport. Finally, we explored the relationship between peritoneal fibrosis and lymphangiogenesis in rats that were administered chlorhexidine gluconate (CG) into the abdominal cavity, which provides a model of chemically induced peritoneal inflammation/fibrosis.30–32 This work is the first report to show that lymphangiogenesis is linked to the peritoneal fibrosis that is often associated with a high peritoneal transport rate. 相似文献
56.
Yuichiro Hashida Satoshi Yasukochi Kiyohiro Takigiku Tesshu Otagiri Nao Inoue Yusuke Nakano Kohta Takei Yoshiyuki Maekawa Kentaro Umezu Takahiko Sakamoto Yorikazu Harada 《Journal of Echocardiography》2013,11(2):66-68
Aortic arch thrombosis (AAT) of the neonate is rare but life-threatening by fatal compromise associated with thrombotic obstruction of the ascending aorta. We report a neonate with AAT who demonstrated a severe coarctation of the aorta and cerebral hypo-perfusion immediately after birth. Echocardiography confirmed the diagnosis of AAT on the findings of a large thrombus located on the transverse arch and blocking the cervical arterial branches. Low-molecular-weight heparin reduced the size of the thrombus and improved the hemodynamics of coarctation and cerebral perfusion. Echocardiography is a powerful tool to make a diagnosis and to monitor the size and regression of AAT. 相似文献
57.
Kure-Hattori I Watari I Takei M Ishida Y Yonemitsu I Ono T 《Archives of oral biology》2012,57(7):987-994
Lubrication of synovial joints reduces the coefficient of friction of the articular cartilage surface. To investigate the effect of malocclusion on the lubrication of the temporomandibular joint (TMJ), we evaluated lubricin expression in the rat TMJ immunohistochemically, under conditions of functional lateral shift of the mandible, during period of growth. Thirty 5-week-old male Wistar rats were divided into experimental, recovery, and control groups. Each rt in the experimental and recovery groups was fitted with an acrylic-plate guiding appliance. The rats in the experimental and control groups were killed at 14 and 28 days after the appliance was attached. Each rat in the recovery group was detached from the appliance at 14 days, and was killed 14 days after the appliance was removed. In the experimental group, the expression of lubricin staining in TMJ cartilage was significantly decreased during the experimental period. In the recovery group, the expression of lubricin staining in TMJ cartilage was significantly greater than in the experimental group, and there was no significant difference at 28 days between the control and recovery groups. Analysis of these data suggests that a functional lateral shift of the mandible during the growth period influences lubrication of the TMJ. 相似文献
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Giulia Bicchierai Paolina Tonelli Alba Piacenti Diego De Benedetto Cecilia Boeri Ermanno Vanzi Simonetta Bianchi Donatello Cirone Maninderpal Kaur Gill Vittorio Miele Jacopo Nori 《The breast journal》2020,26(7):1276-1283
One of the most important indications for contrast‐enhanced breast imaging is the presurgical breast cancer (BC) staging. This is a large‐scale single‐center experience which evaluates the role of CEDM in presurgical staging and its impact on surgical planning. The aims of this retrospective study were to define the diagnostic performance of CEDM in the presurgical setting and to identify which types of patients could benefit from having CEDM. We selected 326 patients with BC who underwent CEDM as preoperative staging and had breast cancer‐related surgery at our institution. We analyzed those cases in which CEDM led to additional imaging or biopsy and those in which it changed the type of surgery that was planned according to conventional breast imaging (CI) techniques (digital mammography, tomosynthesis and bilateral handheld ultrasound). CEDM sensitivity in identifying the index lesion and sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, and accuracy in the correct preoperative staging of BC of the whole population and in various subgroups were calculated. CEDM sensitivity for the index lesion was 98.8% (322/326), which led to additional breast imaging in 23.6% (77/326) of patients and additional biopsies in 17.5% (57/326). CEDM changed the type of surgery in 18.4% (60/326). In the preoperative breast cancer staging, CEDM sensitivity, specificity, PPV, NPV, and accuracy produced results of 93%, 98%, 90%, 98%, and 97%, respectively. CEDM performance was better in patients with palpable lesions. CEDM has an excellent diagnostic performance in the presurgical staging of BC. Symptomatic patients with palpable lesions benefitted most from preoperative CEDM, with a statistically significant difference compared with nonpalpable. 相似文献
60.
S. Mizuno H. Inoue A. Tanemura Y. Murata N. Kuriyama Y. Azumi M. Kishiwada M. Usui H. Sakurai M. Tabata R. Yamada N. Yamamoto K. Sugimoto K. Shiraki Y. Takei S. Isaji 《Transplantation proceedings》2014