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991.
Eimir Perez-Arjona Manuel Dujovny Federico Vi?as Hun K Park Sandra Lizarraga Thomas Park Fernando G Diaz 《Neurological research》2002,24(1):29-40
The problem of child abuse and the central nervous system implications are reviewed from a multidimensional approach. Statistics regarding prevalence, risk factors, epidemiological considerations, and physiological aspects are studied. The incidence is reviewed in the United States and in other countries where incidence and social services are also described. Implications for prevention efforts are considered. 相似文献
992.
José M. Vila Pascual Medina Gloria Segarra Paloma Lluch Federico Pallardó Blas Flor & Salvador Lluch 《British journal of clinical pharmacology》1999,48(2):223-229
AIMS: The therapeutic action of tricyclic agents may be accompanied by unwanted effects on the cardiovascular system. The evidence for the effects on vascular and nonvascular smooth muscle comes from animal studies. Whether these studies can be extrapolated to human vessels remains to be determined. Therefore, the present study was designed to investigate the influence of amitriptyline, nortriptyline and sertraline on the contractile responses of human isolated mesenteric arteries to electrical field stimulation, noradrenaline and potassium chloride. METHODS: Arterial segments (lumen diameter 0.8-1.2 mm) were obtained from portions of the human omentum during the course of 41 abdominal operations (22 men and 19 women), and rings 3 mm long were mounted in organ baths for isometric recording of tension. In some artery rings the endothelium was removed mechanically. RESULTS: In precontracted artery rings amitriptyline, nortriptyline and sertraline (3x10(-7)-10(-4) m ) produced concentration-dependent relaxation that was independent of the presence or absence of vascular endothelium. Incubation with indomethacin (3x10(-6) m ) reduced the pD2 values thus indicating the participation of dilating prostanoid substances in this response. Amitriptyline and nortriptyline inhibited both the neurogenic-and noradrenaline-induced contractions. In contrast, only the highest concentration of sertraline reduced the adrenergic responses. Amitriptyline, nortriptyline and sertraline inhibited contractions elicited by KCl and produced rightward shifts of the concentration-response curve to CaCl2 following incubation in calcium-free solution. CONCLUSIONS: These results indicate that amitriptyline and nortriptyline could act as adrenoceptor antagonists and direct inhibitors of smooth muscle contraction of human mesenteric arteries, whereas sertraline might principally exert its action only as direct inhibitor of smooth muscle contraction. This relaxant mechanism involves an interference with the entry of calcium. 相似文献
993.
The arrival of anti-TNF-α to the clinic has been the most successful example of translational research. However, clinical experience has shown that these compounds do not induce clinical remission in half of rheumatoid arthritis (RA) patients. Recently, new biological drugs against non-cytokine targets have been available for RA patients. These compounds deplete B cells or interfere with the activation of T cells and have also shown effectiveness in controlling signs, symptoms and structural damage progression in RA. Second generation B-cell depletion therapies are progressing in the pipeline of several pharmaceutical companies. These compounds will likely improve the immunogenicity and formulation of rituximab, but it is improbable that they will improve the remission rate achieved by the anti-TNF-α δρυγσ. Currently, regulation of signal transduction has evolved into an important field of drug research, and small molecule inhibitors for a number of pathways are tested as new anti-inflammatory agents. For rheumatic diseases, specific Jak3 and Syk inhibitors are, so far, the most successful compounds representing a significant advance over p38 mitogen-activated protein kinase (MAPK) inhibitors. 相似文献
994.
995.
Ana Ramos PhD Federico Ballenilla MD Patricia Martin MD 《Seminars in Ultrasound, CT and MRI》2008,29(1):47-59
There are several processes implicated as uncommon causes of temporal lobe epilepsy. Trauma is the leading cause of epilepsy in young adults, intracerebral blood collection being the most consistent risk factor of seizures, especially subdural hematomas and brain contusions. Infarction is the entity most commonly related to epilepsy in the elderly population. Seizures usually present as complex seizures with high recurrence between 6 months and 2 years after stroke. There are some radiological characteristics of the affectation associated with high risk of early and late seizures. Noninfectious limbic encephalitis is a syndrome characterized by seizures, memory loss, and confusion. It includes paraneoplasic and non-paraneoplasic limbic encephalitis, both presenting as hyperintense lesion affecting temporobasal regions more evident with fluid-attenuated inversion recovery sequences. Paraneoplasic limbic encephalitis is associated with several types of tumor-induced autoimmunity against the nervous system. The tumors most frequently implicated are the lungs, testis, and breast, including Hodgkin's lymphoma, teratoma, and thymoma in young patients. Once a tumor is excluded, non-paraneoplasic limbic encephalitis has to be considered by investigating the presence of antibodies against voltage-gated potassium channels. It is associated with hyponatremia and responds to regimens of steroids, plasma exchange, and intravenous immunoglobulins. Finally, herpetic limbic encephalitis is also associated with seizures, accompanied by fever and neurologic symptoms. It presents characteristic findings and distribution on magnetic resonance imaging, which shows abnormalities in more than 90% of patients with proven Herpes simplex virus type 1. 相似文献
996.
Excessive dorsiflexion (dorsal tilting) of the lunate on a lateral wrist radiograph can be an important sign of carpal injury. Lunate dorsiflexion is a well-recognized sign of an intercarpal ligamentous injury pattern known as dorsal intercalated segment instability (DISI). It is less well recognized that excessive dorsal tilting of the lunate (DISI configuration) can also be produced by displacement of a scaphoid waist fracture. Since the management and prognosis of displaced scaphoid fractures may be quite different from those for nondisplaced fractures, radiologists can make an important contribution by recognizing dorsal tilting of the lunate and appreciating that it may be an important, indirect sign of scaphoid fracture displacement, which may not be directly visualized with standard wrist radiography. In this setting, computed tomography or complex motion tomography may be helpful for further evaluation of the scaphoid fracture. 相似文献
997.
998.
Ettore Squillaci Marcello Crecco Maria Luisa Grandinetti Federico Maspes Gloria Lo Presti 《European radiology》1994,4(5):410-420
The role of magnetic resonance angiography (MRA) in the evaluation of vascular involvement was studied in 55 patients with abdominal neoplasms. A 2-D time-of-flight (TOF) technique was used in 18 patients. All patients underwent CT and MR examinations before MRA. Also, MR angiograms were compared with digital subtraction angiography in 22 cases, with Doppler US in 13 cases, and with surgical findings in 20 cases. In all patients with liver neoplasms (n = 29) MRA demonstrated the absence of flow in the infiltrated segments. Pericapsular neovascularization was observed in 12 patients. Portal vein involvement was correctly detected in 27 patients. In all cases MRA demonstrated the relationship between the tumor and venous structures. Portosystemic shunts were visualized in 20 of 21 patients with portal hypertension. Vena cava thrombosis (3 cases), compression (5 cases), and displacement (2 cases) were correctly demonstrated. In renal (n = 6) and adrenal gland (n = 3) tumors renal vein compression was correctly detected in 2 cases, displacement in 1 case, and thrombosis in 3 cases, with only 1 false-positive finding. In 7 patients with pancreatic tumors MRA demonstrated splenic vein thrombosis in 2 cases and compression in 2 cases, with one false-positive finding. Our results indicate that MRA provides precise information regarding venous vascular involvement in abdominal neoplasms, but preoperative arterial mapping is still problematic.
Correspondence to: E. Squillaci 相似文献
999.
Michael Cunningham Ramsey Majzoub Pascal C. R. Brouha Luis A. Laurentin-Perez Deepak K. Naidu Claudio Maldonado Joseph C. Banis Federico Grossi Johannes M. Frank John H. Barker 《European Journal of Trauma》2004,30(1):12-16
Abstract Composite tissue allotransplantation (CTA) has recently
emerged as a new therapeutic modality to reconstruct major
tissue defects of the face, larynx, and extremities. However,
because the risk-versus-benefit ratio for CTA procedures has not
yet been defined, the decision as to whether or not to perform
these new reconstructive techniques is based on subjective
opinions rather than objective data. To address this problem,
the authors developed a reliable and valid instrument to
objectively assess the relative risk that individuals are
willing to accept in order to receive the benefits of various
CTA procedures. 相似文献
1000.
L. Chessa P. Petrinelli A. Antonelli M. Fiorlli R. Elli L. Marcucci A. Federico E. Gandini 《American journal of medical genetics. Part A》1992,42(5):741-746
We identified a subgroup of ataxia-telangiectasia (AT) patients (2 sibs and 1 unrelated case) characterized by typical clinical manifestations of the disease and cellular radiosensitivity intermediate between classical AT and normal subjects. Our data and a literature review of the intermediate radiosensitivity AT cases show that radioresistant DNA synthesis, cellular radiosensitivity (measured in terms of survival and chromosome break-age), and the clinical hallmarks behave independently. This raises a number of interesting questions about the correlation between radiobiological and clinical features, and about the nature of the AT gene(s). 相似文献