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91.
92.
OBJECTIVE: To report a rare presentation of metastatic orbital rhabdomyosarcoma and the corresponding findings on magnetic resonance imaging (MRI). DESIGN: Interventional case report. RESULTS: A 29-year-old white man was diagnosed with rhabdomyosarcoma of the left sinus and orbit for which he was treated with chemotherapy and radiation. Eighteen months after diagnosis, he returned with subacute right eye pain and dysmotility of his extraocular muscles. MRI revealed solitary enlargement of the right medial rectus muscle, and thyroidopathy was suspected. Over the next 2 months, symptoms progressed, and proptosis developed. MRI showed infiltration of seven extraocular muscles. A biopsy of right orbital tissues and the right medial rectus muscle was performed. Special tissue typing confirmed metastatic alveolar rhabdomyosarcoma. The patient underwent palliative radiation therapy and chemotherapy, but he ultimately died of disseminated disease. CONCLUSIONS: Rhabdomyosarcoma can rarely metastasize to the extraocular muscles. Earlier recognition of orbital metastasis through radiographic and biopsy findings, along with prompt and aggressive treatment, may prevent fulminant spread of rhabdomyosarcoma. 相似文献
93.
Condorelli DF Mudò G Trovato-Salinaro A Mirone MB Amato G Belluardo N 《Molecular and cellular neurosciences》2002,21(1):94-113
Glial connexins (Cxs) make an extensively interconnected functional syncytium created by a network of gap junctions between astrocytes and oligodendrocytes. Among Cxs expressed in the brain, Cx30 is expressed in grey matter astrocytes, as shown at the protein level by immunoistochemistry. In the present study we aimed to perform a detailed study of the regional distribution of Cx30 mRNA in the adult and postnatal developing rat brain, analyzing its expression by in situ hybridization, and determining its cell type localization by double labeling. Recently, it has been suggested that neuronal activity may control the level of intercellular communication between astrocytes through gap junctions channels. Thus, a second aim of the present study was to investigate the short-term effects of kainate-induced seizures on Cx30 expression. The results showed that, in basal condition, Cx30 was expressed only in grey matter astrocytes with distinct regional patterns in developing and adult brain. Kainate treatment induced strong and region-specific changes of astroglial Cx30 mRNA levels and expression of Cx30 mRNA in neuronal cells undergoing cell death, suggesting a direct or indirect involvement of this connexin in the neuronal apoptotic process. 相似文献
94.
Previous studies have suggested that tumor hypoxia could be exploited for cancer gene therapy. Using hypoxia-responsive elements derived from the human vascular endothelial growth factor gene, we have generated vectors expressing a bacterial nitroreductase (NTR) gene that can activate the anticancer prodrug CB1954. Stable transfectants of human HT1080 tumor cells with hypoxia-inducible vectors were established with G418 selection. Hypoxic induction of NTR protein correlated with increased sensitivity to in vitro exposure of HT1080 cells to the prodrug. Growth delay assays were performed with established tumor xenografts derived from the same cells to detect the in vivo efficacy of CB1954 conversion to its cytotoxic form. Significant antitumor effects were achieved with intraperitoneal injections of CB1954 both in tumors that express NTR constitutively or with a hypoxia-inducible promoter. In addition, respiration of 10% 02 increased tumor hypoxia in vivo and enhanced the antitumor effects. Taken together, these results demonstrate that hypoxia-inducible vectors may be useful for tumor-selective gene therapy, although the problem of delivery of the vector to the tumors, particularly to the hypoxic cells in the tumors, is not addressed by these studies. 相似文献
95.
BACKGROUND: The incidence of testicular carcinoma in the United States has increased significantly over the last two decades. Germ cell tumors form the majority of malignant testicular tumors. With advances in diagnosis and therapeutic approaches, germ cell tumors are now highly sensitive to treatment, providing long-term survival. It has been speculated that the incidence of bilateral germ cell tumors may increase due to the improved survival of patients with unilateral germ cell tumors. In this report, the authors present a study of bilateral germ cell tumors of the testis in men who were treated at The University of Texas M. D. Anderson Cancer Center over a 20-year period with emphasis on their incidence, histologic features, and clinical features. METHODS: Between 1978 and 1999, 2431 patients with testicular germ cell tumors were treated at The University of Texas M. D. Anderson Cancer Center. Among these, 24 patients with bilateral germ cell tumors were identified. Clinical records and all available pathology slides of the tumors were reviewed. RESULTS: The overall incidence of bilateral germ cell tumors in the patients with testicular germ cell tumors was 1% (24 of 2431 patients). The incidence was 1.8% (14 of 776 patients) in patients with seminoma and 0.6% (10 of 1655 patients) in patients with nonseminomatous germ cell tumors. Patients with seminoma who were age = 30 years at the time of initial diagnosis had a higher incidence of bilateral tumors compared with older men. Twenty of 24 patients with bilateral germ cell tumors had metachronous tumors, and 4 patients had synchronous tumors. Among the patients with metachronous tumors, 70% of second tumors occurred within 5 years; the longest interval between the first and second tumors was 15 years. The outcome of patients with bilateral germ cell tumors was excellent; only 1 of 24 patients died of metastatic disease. CONCLUSIONS: The overall incidence of bilateral testicular germ cell tumors was 1% in patients who were treated at The University of Texas M. D. Anderson Cancer Center over the past two decades. The incidence of bilateral germ cell tumors was related to the histologic type of the initial tumor and to the patient's age at initial presentation in patients with seminoma. Thus, patients in the second or third decade of life who presented with seminomas as their initial tumor were more likely to develop a second germ cell tumor compared with patients in the fourth or fifth decade of life. These findings have potentially important implications for clinical management by identifying a population of patients with germ cell tumors who are at risk of developing a second tumor and also for studying risk factors of bilateral germ cell tumors of the testis. 相似文献
96.
Wolfe GI Barohn RJ Foster BM Jackson CE Kissel JT Day JW Thornton CA Nations SP Bryan WW Amato AA Freimer ML Parry GJ;Myasthenia Gravis-IVIG Study Group 《Muscle & nerve》2002,26(4):549-552
We initiated a randomized, double-blinded, placebo-controlled trial of intravenous immunoglobulin (IVIG) treatment in myasthenia gravis (MG). Patients received IVIG 2 gm/kg at induction and 1 gm/kg after 3 weeks vs. 5% albumin placebo. The primary efficacy measurement was the change in the quantitative MG Score (QMG) at day 42. Fifteen patients were enrolled (6 to IVIG; 9 to placebo) before the study was terminated because of insufficient IVIG inventories. At day 42, there was no significant difference in primary or secondary outcome measurements between the two groups. In a subsequent 6-week open-label study of IVIG, positive trends were observed. 相似文献
97.
98.
Mino D Amato D Cuevas ML Fonseca ME Búrbano G Wacher N Lifshitz A 《Archives of medical research》2002,33(6):524-530
BACKGROUND: Our objective was to assess the relationship of hormones such as cortisol and dehydroepiandrosterone-sulfate (DHEA-S) with insulin resistance and overweight. METHODS: We designed and conducted a cross-sectional, observational survey consisting of home visits within a previously defined area of Mexico City. The study included 303 apparently healthy volunteers from a middle-class socioeconomic urban community. We measured glucose, cholesterol, triglycerides, insulin, cortisol, and DHEA-S. Insulin resistance (IR) was defined as belonging to the first quartile of fasting glucose/insulin ratio (G/IR) distribution or fourth quartile of IR (HOMA). Overweight was defined as body mass index (BMI) > or =25 kg/m(2). RESULTS: To predict IR in women < or =35 years of age, principal component analysis (PCA) disclosed three components: 1) cholesterol, BMI, and diastolic blood pressure (DBP); 2) cholesterol, triglycerides, and cortisol, and 3) dehydroepiandrosterone-sulfate [DHEA-S]. Solely the latter (DHEA-S) was significantly associated with IR (odds ratio [OR] = 1.80, confidence interval 95% [CI 95%] 1.11-2.91, p = 0.015). For men < or =35 years of age, there were two components: 1) cholesterol, triglycerides, BMI, and DBP, and 2) DHEA-S, cholesterol, and cortisol. Component 1 was significantly associated with IR (OR = 5.65; CI 95% 1.62-19.65, p = 0.006). To predict overweight in women >35 years of age, there were three components, including 1) cholesterol and triglycerides, 2) cortisol, and 3) DHEA-S and G/IR. Component 2 was significantly associated with overweight (OR = 0.38, CI 95% 0.23-0.64, p = 0.000). CONCLUSIONS: In women < or =35 years of age, high DHEA-S levels were associated with insulin resistance, which suggests that in young women DHEA-S exerts anti-estrogenic action, perhaps caused by its competitive binding with the estrogen receptor. Additionally, in women >35 years of age, low cortisol levels were associated with overweight. These associations were not identified for the male subgroup. 相似文献
99.
Ectopia cordis is a rare congenital defect in which the heart is placed externally on the surface of the chest. This article describes the embrylogic events that lead to the various classifications of the defect and how they possibly explain the process of its unusual occurrence in children. While survival in some cases is possible, the ultimate repair is difficult and survival is rare. The most extreme forms of ectopia cordis, especially those with intracardiac defects, have a poor prognosis. Several cases of this rare anomaly with primary repair and staged repair are discussed. 相似文献
100.
Recurrent antiphospholipid-related deep vein thrombosis as presenting manifestation of systemic lupus erythematosus 总被引:1,自引:0,他引:1
Gattorno M Molinari AC Buoncompagni A Acquila M Amato S Picco P 《European journal of pediatrics》2000,159(3):211-214
Antiphospholipid antibodies (aPL) are frequently associated with thrombotic disorders in the so-called antiphospholipid syndrome.
Together with anticardiolipin antibodies (aCL), lupus anticoagulant (LA) is the main diagnostic tool for aPL detection. Since
LA determination is based on the finding of prolonged clotting time in vitro, concomitant anticoagulant therapy may significantly
interfere with its detection. We report a case of a boy in whom recurrent aPL-related thrombosis heralded for several months
the onset of systemic lupus erythematosus (SLE). Abnormally increased in vitro clotting times at the time of the second thrombotic
event led to the suspicion of the presence of LA activity. However, this latter finding was difficult to interpret since the
patient was already on heparin treatment at the time of our first observation. Thus, LA was assayed using a commercial kit
in which a heparin neutralizer is included (Staclot LA). Two consecutive samples from the patient were compared with eight
patients on anticoagulant therapy for non-aPL-related thrombotic events and 20 healthy controls. The study showed that, taking
into account the concomitant anticoagulant treatment, Staclot LA was positive only in the propositus, raising the suspicion
of a possible aPL-related origin of the thrombotic event. This issue was definitively confirmed in a subsequent follow-up.
Conclusion The present report shows that aPL-related deep vein thrombosis can be the earliest clinical manifestation of pediatric SLE,
and that Staclot LA may have a role in LA detection during the course of anticoagulant treatment.
Received: 6 October 1998 / Accepted: 15 September 1999 相似文献