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11.
Mucosal leishmaniasis of the upper respiratory tract is usually associated with the visceral form or is found in immunosuppressed individuals. This report presents a case of isolated mucosal leishmaniasis in an immunocompetent patient, whose diagnosis mainly rested on histology and positive polymerase chain reaction result for Leishmania donovani in the laryngeal tissue. A 59-year-old man, who never lived outside Italy, showed a subglottic mucosal polypoid-like lesion. The typical morphological picture and positive polymerase chain reaction result for L donovani by DNA extracted from laryngeal biopsy specimens allowed the diagnosis of mucosal leishmaniasis. Specific amphotericin B therapy was started, resulting in clinical and endoscopic improvement. Increased knowledge about the histological and molecular tissue analysis of Leishmania enhances the diagnostic testing for mucosal leishmaniasis, as primary mucosal leishmaniasis may occur in both immunosuppresed and immunocompetent patients who travel to or reside in areas endemic for Leishmania.  相似文献   
12.
The isolation and analysis of nucleated fetal cells (NFCs) from maternal blood may represent a new approach to noninvasive prenatal diagnosis. Although promising, these techniques require highly accurate separation of NFCs from nucleated cells of maternal origin; the two major problems limiting these techniques are the relative rarity of fetal cells in maternal blood and the need to establish their fetal origin. We now report a novel procedure that has allowed accurate separation of NFCs from maternal cells. The technique reported involves direct micromanipulator isolation of histochemically identified hemoglobin F‐positive nucleated cells to obtain fetal nucleated red blood cells (FNRBCs) of high yield and purity. Using this technique, followed by cell‐by‐cell multicolor fluorescence in situ hybridization (FISH) analysis of purified FNRBCs, we were able to detect some of the most common human aneuploidies (including Down syndrome, Klinefelter syndrome, and trisomy 13) in 33 pregnant women referred for amniocentesis. The procedure used, which can be completed in <72 hrs, produced complete concordance with the results of amniocentesis. We also confirm findings of prior studies suggesting that the number of FNRBCs in maternal circulation is remarkably higher in abnormal pregnancies than in normal pregnancies, especially in women carrying a fetus with trisomy 21. © 2001 Wiley‐Liss, Inc.  相似文献   
13.
BACKGROUND: Lethal varicella in immunocompetent hosts is rare and its pathogenesis is largely unknown. The discovery of glycoprotein E (gE) mutants showing attributes consistent with increased virulence in vitro and in animal models, provided a possible molecular mechanism underlying a more aggressive virus infection. However, these mutants have never been associated with unusually severe clinical cases. OBJECTIVES: To varicella-zoster virus (VZV) mutations that correlate with increased virulence. RESULTS: We report a case of fatal hepatitis caused by a VZV bearing a novel mutation on the 3B3 monoclonal antibody epitope of gE in an immunocompetent host. CONCLUSIONS: This report describes a mutant VZV responsible for an aggressive clinical course in an immunocompetent host. Linking these severe clinical presentations of VZV infection to virus mutations might provide insights into the underlying pathogenic mechanisms.  相似文献   
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Nine patients undergoing regular dialytic treatment for more than 60 months showed clinical and radiologic features of a noninfective and destructive spondyloarthropathy. The cervical spine was most affected (100%), followed by the dorsal (three patients, 33.3%) and the lumbar spine (two patients, 22.2%). Typically, radiographs and CT scans revealed narrowing of intervertebral spaces, with destruction or sclerosis of the subchondral bone of the vertebral plate.Autopsy was performed on three patients; histologic study demonstrated the presence of large amyloid deposits containing 2-microglobulin ( 2-m) in the discs and peridiscal ligaments.A radiographic follow-up of the cervical spine was performed in seven patients after a period of 12 months and showed that the bone destruction in DSA is very rapid and progressive. The lower biocompatibility of the cuprophan membranes of dialyzers is probably the factor most responsible for hyperproduction of 2-m and subsequently osteoarticular deposition of a new type of amyloidosis.  相似文献   
16.
The aim of the present study was to investigate the relationships between poststroke depression (PSD), lesion location and cognitive deficits after stroke. We studied 20 patients within the first month after clinical onset (T1), and one year later (T2). PSD was observed in 55% of patients at T1 and 35% of patients at T2. At T1, depression was reliably correlated with dorsal lesions in the right-hemisphere and anterior lesions in the left hemisphere. Lesion location was no longer a significant factor determining PSD at T2. Changes in PSD, from T1 to T2, were inversely correlated with the performances in cognitive tests exploring the domains of attention, visuospatial learning, executive/motor functions, and with the global composite cognitive score. Our data suggest that: 1) in the mix of influences that may produce PSD, lesion location is the main factor determining mood changes after stroke in the first month; 2) PSD produces deficits in attention, learning, and executive/motor functions, without affecting language and other cognitive domains.
Sommario Scopo di questo studio sono i rapporti tra la depressione post-stroke (PSD), la localizzazione della lesione cerebrovascolare e i disturbi cognitivi conseguenti alla lesione. Abbiamo studiato 20 pazienti entro il primo mese dall'episodio ictale (T1) ed un anno dopo (T2). La PSD era osservabile nel 55% dei pazienti a T1 e nel 35% dei pazienti a T2. A T1, la PSD era significativamente correlata con lesioni dorsali nell'emisfero di destra e con lesioni anteriori nell'emisfero di sinistra. Queste correlazioni non erano più significative a T2. Le variazioni della PSD da T1 a T2 erano inversamente correlate con le prestazioni dei pazienti a compiti cognitivi di attenzione, apprendimento visuospaziale, funzioni esecutivo/motorie, e con un punteggio cognitivo composito.Questi dati suggeriscono che: 1) tra le numerose cause che possono produrre la PSD, la localizzazione della lesione sembra essere il fattore principale nel primo mese dopo l'episodio cerebrovascolare; 2) la PSD produce disturbi attentivi, di apprendimento visuospaziale ed esecutivi/motori senza determinare disturbi nella sfera del linguaggio e di altre funzioni cognitive.
  相似文献   
17.
PURPOSE: To evaluate the prognostic value of P-glycoprotein and clinicopathologic parameters in a large series of high-grade osteosarcoma (OS) patients treated at the Rizzoli Institute. PATIENTS AND METHODS: With the use of immunohistochemistry, P-glycoprotein was assessed in 149 patients with primary, nonmetastatic, high-grade OS who were homogeneously treated with chemotherapy protocols based on doxorubicin, high-dose methotrexate, and cisplatin and the addition of ifosfamide in the postoperative phase. RESULTS: P-glycoprotein positivity was found in 47 of 149 cases (32%) and was significantly associated with a higher incidence of relapse and a worse outcome, as was age younger than 12 years and tumor volume greater then 150 mL at diagnosis. Multivariate analysis further confirmed the prognostic value of these parameters, which all were independent adverse prognostic factors. Event-free survival and proportional hazards regression analyses confirmed that overexpression of P-glycoprotein at clinical onset is the most important adverse prognostic factor for high-grade OS patients treated with these chemotherapy protocols. CONCLUSION: Increased P-glycoprotein levels, together with tumor volume and age, should be taken into consideration to identify, at time of diagnosis, subgroups of OS patients with a higher risk of recurrence. This subgroup identification will constitute the basis for drawing individualized treatment protocols on the basis of risk evaluation, with the aim of using more aggressive chemotherapy, or combination chemotherapy with other adjuvants, only in those patients for which more aggressive regimens are strictly necessary and warranted.  相似文献   
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Geometric cis, trans isomers, derivatives of 2-substituted-1,3-dioxanes were designed and studied as antimuscarinic agents. The synthesized compounds were evaluated as perchlorides and methiodides by functional tests with rabbit vas deferens (putative M1), guinea-pig heart (M2) and guinea-pig ileum (M3). The effect of the replacement of a trimethylammonium group with a dimethysulfonium in the two rings was also evaluated. Pharmacological results indicate that the 1,3-dioxane nucleus shows the highest stereoselective values on the studied receptors.  相似文献   
20.
Spontaneous esophageal perforation (Boerhaave's syndrome) remains a difficult diagnostic and management problem with controversial recommendations regarding its treatment. The clinical manifestations of the disease are variable, and may be misleading, thus delaying accurate recognition. On the other hand, in view of the rapid onset of severe complications, particularly mediastinitis, a prompt diagnosis is essential to a better prognosis, successful operative outcome and potential survival. A case of spontaneous perforation of the thoracic esophagus penetrating the left pleural space treated within 4 hours from admission to the Emergency Room, with minimal surgical intervention is presented. Despite negative chest X-ray, a thoracic TC showed a small right sided effusion with left sided hydropneumothorax, and the definitive diagnosis was obtained by contrast study with a water soluble medium which showed the leak communicating freely with the left pleural space. The patient underwent repair by thoracic approach, the rupture was closed with a primary suture without flap reinforcement and the pleural space drained with the placement of single chest thoracostomy tube. The recovery was uneventful. The analysis of this case report and of the appropriate literature reveals that a poor prognosis is correlated with the time elapsed between the perforation and treatment. In conclusion the importance of an early aggressive surgical treatment for the Boerhaave's syndrome is emphasized, because any perforation treated more than 24 hours after the onset of symptoms, irrespective of the procedure used, is associated with a significantly higher morbility and mortality.  相似文献   
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