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81.
Utilizing prognostic and predictive factors in breast cancer 总被引:7,自引:0,他引:7
Opinion statement In order to make optimal treatment recommendations for patients with early-stage breast cancer, it is essential to accurately
determine the patient’s underlying risk of disease recurrence and choose a therapy to which the individual is most likely
to respond. Lymph node status, tumor size, histopathologic features including tumor type and grade, and hormone receptor status
are well-accepted prognostic factors related to breast cancer. In addition, hormone receptor status is a very strong predictor
of response to hormonal therapy. However, our currently accepted prognostic and predictive factors fall short and there is
a critical need to more accurately identify those most likely to require or benefit from particular therapies. Attention has
therefore focused on the determination of novel prognostic and predictive factors. The most promising new factor is the level
of urokinase plasminogen activator and its inhibitor plasminogen activator inhibitor. Other putative factors include proliferative
rate, the presence of lymphatic or vascular invasion, human epidermal growth factor receptor 2 (HER-2/neu or erbB-2) positivity,
the presence of micrometastases in lymph nodes or bone marrow, and gene expression profile by microarray analysis, and by
RNA-based methodology. Data regarding potential new prognostic factors are constantly emerging. These studies are frequently
challenging to interpret as they are often retrospective, based on relatively small numbers of patients, include a mix of
treated and untreated women, and often do not control for other known prognostic factors. Therefore, new data must be interpreted
with caution. 相似文献
82.
Madan R Bhatia A Chakithandy S Subramaniam R Rammohan G Deshpande S Singh M Kaul HL 《Anesthesia and analgesia》2005,100(6):1622-1626
In this double-blind, randomized, placebo-controlled study, we evaluated the efficacy and safety of different doses of prophylactic IV dexamethasone for postoperative nausea and vomiting (PONV) in 168 children (aged 2-15 yr) scheduled for strabismus surgery. Patients received IV dexamethasone 0.25 mg/kg (D 0.25), 0.5 mg/kg (D 0.5), 1.0 mg/kg (D 1), or saline (S) immediately after induction of general anesthesia. Patients were discharged 24 h after surgery. Nausea and vomiting were assessed at 0-2, 2-6, and 6-24 h after surgery. Blood glucose was measured preoperatively and at 4 h after study drug administration. Wound healing and infection were assessed after 1 wk. More patients in group S had vomiting at 0-2, 2-6, and 6-24 h (P = 0.001, P = 0.003, and P = 0.04, respectively) and required larger doses of rescue antiemetics compared with the dexamethasone groups. Fewer patients in the dexamethasone groups (6, 3, and 6 in D 0.25, D 0.5, and D 1, respectively) had severe PONV compared with group S (P = 0.001). No significant increase in postoperative blood glucose levels was observed and wound healing was satisfactory in all four groups. The results suggest that dexamethasone 0.25 mg/kg is more effective than saline and equally effective compared with larger doses for preventing PONV for pediatric strabismus surgery. 相似文献
83.
Chowdhury UK Airan B Kothari SS Pandey A Subramaniam KG Venugopal P 《The Annals of thoracic surgery》2005,80(1):336-338
Five patients of right pulmonary artery-to-left atrium communication presented with special emphasis on the clinical presentation, anatomic variations, diagnostic considerations, and management options. An individualized management algorithm is recommended. 相似文献
84.
Mechanism of atrial flutter occurring late after orthotopic heart transplantation with atrio-atrial anastomosis 总被引:1,自引:0,他引:1
Marine JE Schuger CD Bogun F Kalahasty G Arnaldo F Czerska B Krishnan SC 《Pacing and clinical electrophysiology : PACE》2005,28(5):412-420
OBJECTIVE: We sought to better define the electrophysiologic mechanism of atrial flutter in patients after heart transplantation. BACKGROUND: Atrial flutter is a recognized problem in the post-cardiac transplant population. The electrophysiologic basis of atrial flutter in this patient population is not completely understood. METHODS: Six patients with cardiac allografts and symptoms related to recurrent atrial flutter underwent diagnostic electrophysiologic study with electroanatomic mapping and radiofrequency catheter ablation. Comparison was made with a control non-transplant population of 11 patients with typical counterclockwise right atrial flutter. RESULTS: In each case, mapping showed typical counterclockwise activation of the donor-derived portion of the right atrium, with concealed entrainment shown upon pacing in the cavotricuspid isthmus (CTI). The anastomotic suture line of the atrio-atrial anastomosis formed the posterior barrier of the reentrant circuit. Ablation of the electrically active, donor-derived portion of the CTI was sufficient to terminate atrial flutter and render it noninducible. Comparison with the control population showed that the electrically active portion of the CTI was significantly shorter in patients with transplant-associated flutter and that ablation was accomplished with the same or fewer radiofrequency lesions. CONCLUSIONS: Atrial flutter in cardiac transplant recipients is a form of typical counterclockwise, isthmus-dependent flutter in which the atrio-atrial anastomotic suture line forms the posterior barrier of the reentrant circuit. Ablation in the donor-derived portion of the CTI is sufficient to create bidirectional conduction block and eliminate this arrhythmia. Ablation or surgical division of the donor CTI at the time of transplantation could prevent this arrhythmia. 相似文献
85.
86.
The abuse of the illicit drug methamphetamine (METH) is a major concern because it can cause terminal degeneration and neuronal cell death in the brain. METH-induced cell death occurs via processes that resemble apoptosis. In the present review, we discuss the role of various apoptotic events in the causation of METH-induced neuronal apoptosis in vitro and in vivo. Studies using comprehensive approaches to gene expression profiling have allowed for the identification of several genes that are up-regulated or down-regulated after an apoptosis-inducing dose of the drug. Further experiments have also documented the fact that the drug can cause demise of striatal enkephalinergic neurons by cross-talks between mitochondria-, endoplasmic reticulum- and receptor-mediated apoptotic events. These neuropathological observations have also been reported in models of drug-induced neuroplastic alterations used to mimic drug addiction (Nestler, 2001). 相似文献
87.
88.
89.
Chowdhury UK Mishra PK Sharma R Airan B Subramaniam GK Kothari SS Bhan A Patel CD Venugopal P 《The Annals of thoracic surgery》2004,78(2):658-665
Background
The purpose of this investigation was to determine the role of radionuclide studies in evaluating postoperative Fontan hemodynamics and to quantify its diagnostic accuracy.Methods
One hundred five patients (105), aged 11 months to 35 years old, who had undergone univentricular repair, underwent first-pass and multigated acquisition scan 1 month to 10 years after univentricular repair. Forty-five patients with evidence of Fontan failure underwent radionuclide studies using Technetium-99 m as well as cardiac catheterization (group 1). The remaining sixty randomly selected patients with excellent functional status received radionuclide studies alone (group 2). The receiver operating characteristic curve analysis was done to quantify the diagnostic accuracy of the first-pass study.Results
There was paradoxical filling of the right lung after femoral injection in all cases of tunnel or conduit obstruction. A first-pass transit time of 16 to 25 seconds (mean ± standard deviation [SD] = 18.82 ± 2.69) was always associated with Fontan failure and high right atrial pressure (range = 20 to 24 mm Hg, mean ± SD = 22.02 ± 1.58). A first-pass transit time of 16 seconds was associated with a sensitivity of 100% and a specificity of 93.33%. The predictive accuracy of a positive or negative result was 91.8% and 100% respectively. The area measured under the receiver operating characteristic curve indicates that 99.41% (SE ± 0.0035) of the time, the value of first-pass time is higher for the Fontan failure group (group 1) compared to the normal group (group 2; p = 0.000).Conclusions
Our data indicate that Fontan circuit can be reliably evaluated for both anatomic and functional flaws by radionuclide studies; radionuclide first-pass time may be used to predict the chances of Fontan failure postoperatively as well as its presence; and in the presence of atrial fibrillation with fast ventricular rate, analysis using first-pass radionuclide may be impossible and gated equilibrium radionuclide angiocardiography may be the preferred method. Inspection of the systemic ventricular time-activity curve is of crucial importance in this regard. 相似文献90.
Ramkumar KM Latha M Venkateswaran S Pari L Ananthan R Bai VN 《Journal of medicinal food》2004,7(3):366-371
The effects of leaf extract from Gymnema montanum, an endangered and endemic plant, were examined on brain lipid peroxidation in experimental diabetic rats. Ethanolic extract of G. montanum leaves was administered orally (50, 100, and 200 mg/kg of body weight) for 3 weeks, and changes in blood glucose, plasma insulin, and lipid peroxidation markers such as thiobarbituric acid-reactive substances (TBARS), hydroperoxides, and levels of antioxidants, namely, superoxide dismutase, catalase, glutathione peroxidase, reduced glutathione, and glutathione-S-transferase, were examined in the brain of alloxan-induced diabetic rats. Glibenclamide was used as a standard reference drug. A significant increase in the activities of antioxidants was observed in brain on treatment with G. montanum leaf extract and glibenclamide for 3 weeks. Both the treated groups showed significant decreases in formation of TBARS and hydroperoxides in brain, suggesting a role in protective action against lipid peroxidation-mediated membrane damage. Our findings indicate that G. montanum leaf extract possesses antiperoxidative and antioxidant effects in addition to its antidiabetic activity. This report helps to create awareness on the need for conservation of medicinal plants, and G. montanum is one such plant that needs to be conserved through various propagation trials. 相似文献