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991.
The β subunit of high affinity immunoglobulin E (IgE) receptor (FcɛRIβ) and the Clara cell derived inflammatory molecule, CC16 have been cited as candidate genes for atopic asthma on chromosome 11q13. A genetic association study was performed with an intragenic microsatellite repeat of CC16 gene on chromosome 11q12–13 in relation to atopic and non-atopic asthma. Whereas variants of FcɛRIβ at chromosome 11q13 show association with atopy and asthma, no significant association was found between asthma and CC16 genotypes irrespective of atopic status. These data support the candidacy of FcɛRIβ rather than CC16 for the atopic asthma locus on chromosome 11q.  相似文献   
992.
MRI预测垂体腺瘤质地指导手术入路   总被引:2,自引:0,他引:2  
徐翔  黄楹  娄晶  李建珉  只达石 《医学争鸣》2005,26(19):1818-1818
1 临床资料 2002-02/2003-02术后病理证实垂体腺瘤患者肿瘤直径>1 cm,影像学资料齐全84(男37,女47)例,年龄14~76(平均44)岁,病史2 wk~20 a. 以肿瘤的占位效应为主诉49例(58%),其中视力视野改变47例,头痛42例,呕吐以及意识障碍各2例,因内分泌紊乱为主诉35例(42%),其中闭经25例,不孕17例,泌乳5例,性功能减退6例,肢端肥大10例.  相似文献   
993.
Background:This article presents the design of PROFILe, a studyinvestigating which (bio)medical and non-(bio)medical patient characteristicsshould guide more tailored chronic care. Based on this insight, the project aimsto develop and validate ‘patient profiles’ that can be used inpractice to determine optimal treatment strategies for subgroups of chronicallyill with similar healthcare needs and preferences.Methods/Design:PROFILe is a practice-based research comprising fourphases. The project focuses on patients with type 2 diabetes. During the firststudy phase, patient profiles are drafted based on a systematic literatureresearch, latent class growth modeling, and expert collaboration. In phase 2,the profiles are validated from a clinical, patient-related and statisticalperspective. Phase 3 involves a discrete choice experiment to gain insight intothe patient preferences that exist per profile. In phase 4, the results from allanalyses are integrated and recommendations formulated on which patientcharacteristics should guide tailored chronic care.Discussion:PROFILe is an innovative study which uses a uniquelyholistic approach to assess the healthcare needs and preferences of chronicallyill. The patient profiles resulting from this project must be tested in practiceto investigate the effects of tailored management on patient experience,population health and costs.  相似文献   
994.
Diarrhetic Shellfish Poisoning (DSP) results from the consumption of shellfish contaminated with okadaic acid (OA) or one of the dinophysistoxins (DTX). It has been reported that this toxin induces apoptosis in several cell models, but the molecular events involved in this process have not been clarified. In this report we studied intracellular signals induced by OA in Caco-2 cells: mitochondrial membrane potential, F-actin depolymerization, caspases activation, cell proliferation and cell membrane integrity. Results indicate that caspases-8 and -9 increased their activity after 30 min of OA treatment according to their role as initiator caspases. In contrast, activation of the downstream caspase-3 is a later event in the execution phase of apoptosis. Mitochondrial membrane potential changes are detected at 30 min of OA exposure indicating that this is an early response in the apoptotic cascade. F-actin depolymerization occurs after 24h of incubation with OA and this effect is significant at low doses of the toxin. LDH is released into the culture medium, although there is not PI uptake, indicative of a significant cell death in addition to apoptosis. Moreover, OA led to a dose- and time-dependent decrease in cellular proliferation.  相似文献   
995.
Collen  D; Stassen  JM; Larsen  G 《Blood》1988,71(1):216-219
The following mutants of human tissue-type plasminogen activator (t-PA) were constructed by deletion mutagenesis of t-PA cDNA, expressed in Chinese hamster ovary cells and purified to homogeneity: (a) t-PA-delta FE:t-PA lacking both the fibronectin fingerlike (F) domain and the epidermal growth factor (E) domain, (b) t-PA-delta FE1X:t-PA-delta FE with the glycosylated 117Asn mutagenized to Gln, and (c) t-PA-delta FE3X:t-PA-delta FE with the three known glycosylated Asn residues replaced by Gln. The mutant and natural t-PA (Mel-t-PA obtained from melanoma cell culture) were infused intravenously for four hours into rabbits with jugular vein thrombosis at doses ranging between 0.12 and 0.75 mg/kg. Fifty percent thrombolysis, determined by interpolation, was obtained with 0.4 mg/kg Mel-t-PA, 0.37 mg/kg t-PA-delta FE, 0.2 mg/kg t-PA-delta FE1X, and 0.40 mg/kg t-PA-delta FE3X. These infusion rates resulted in plateau levels of t-PA antigen in plasma of 0.055, 2.1, 0.6, and 0.5 micrograms/mL, respectively. At 50% lysis, the residual fibrinogen 30 minutes after the end of the infusion was 100%, 81%, 100% and 85% of baseline, and the residual alpha 2-antiplasmin was 82%, 55%, 85%, and 90%, respectively. These results indicate that t-PA- delta FE1X and t-PA-delta FE3X have a specific thrombolytic activity and fibrin specificity comparable to that of Mel-t-PA. t-PA-delta FE has a comparable specific thrombolytic activity but a lower fibrin specificity than Mel-t-PA. After the end of the infusion, t-PA-related antigen disappeared from plasma with an initial t1/2 of four minutes for Mel-t-PA, 25 minutes for t-PA-delta FE, 42 minutes for t-PA-delta FE1X, and 14 minutes for t-PA-delta FE3X. It is concluded that t-PA can be modified by deletion mutagenesis to yield variants with a markedly longer half-life in the blood. Some of these variants have a specific thrombolytic activity and fibrin specificity similar to that of natural t-PA. These variants may be useful to identify the structures in t-PA responsible for its clearance, specific thrombolytic activity, and fibrin specificity in vivo.  相似文献   
996.
997.
998.
The technical and diagnostic performance of simultaneously acquired low-dose (44% of standard dose) storage-phosphor digital radiographs (system resolution = 0.2 mm, 10 bits) were compared with those of standard-dose conventional bedside radiographs of the chest in 32 patients. The mean optical density (OD) of the lungs (800 measurements) was closer to the ideal density with digital radiography (1.45 OD +/- 0.20 [standard deviation] vs 1.75 OD +/- 0.53) and was less often outside the usable range (2.5% vs 42.5%). Receiver operating characteristic analysis for detection of simulated nodules and monitoring devices (nine readers, 4,608 observations) showed that digital radiography was superior to conventional radiography (P less than .05) for four of the nine readers and equivalent to conventional radiography for five readers. The authors concluded that digital radiography produces more consistent and ideal image density and performs at least as well as conventional radiography under phantom test conditions.  相似文献   
999.
Extraperitoneal paravesical spaces: CT delineation with US correlation   总被引:8,自引:0,他引:8  
The extraperitoneal space around the urinary bladder is lamellate, just like the retroperitoneal space around the kidneys. The bladder, urachus, and obliterated umbilical arteries lie within the perivesical space, surrounded by umbilicovesical fascia, analogous to the perinephric space within the renal fascia. A much larger prevesical space, analogous to the anterior pararenal space, lies anterior and lateral to the umbilicovesical fascia. Posterior to the urinary bladder, the lower uterine segment or seminal vesicles lie within the perivesical space, rather than in a separate compartment, corresponding to the posterior pararenal space. The cul-de-sac, and the inferolateral extension of its peritoneal layers as the rectovaginal or rectovesical septum, separate the posterior perivesical space from the rectum. The sectional anatomy of these spaces, and particularly their computed tomographic and ultrasound appearances, were noted in normal anatomic sections, patients with extraperitoneal fluid collections, and a cadaver into which fluid was injected.  相似文献   
1000.
Weinreb  JC; Cohen  JM; Maravilla  KR 《Radiology》1985,156(2):435-440
Magnetic resonance (MR) imaging was performed on 15 healthy subjects to define the appearance of the iliopsoas muscle and on 15 patients with iliopsoas disease. Seven patients had tumorous involvement of the muscles, five had inflammatory disease, one had retroperitoneal hemorrhage, one had iliopsoas bursitis, and one had bilateral hypertrophy. MR imaging permitted delineation of the muscles and depiction of the disease condition. Transverse MR images alone almost always provided the necessary data to determine the origin and extent of disease. Sagittal images were occasionally useful in defining the extension of disease into the spine. T1-weighted images provided optimal contrast between the muscles and adjacent tissues, while T2-weighted images were more useful for depicting disease within the muscles themselves.  相似文献   
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