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51.
Brain metastasis from transitional cell carcinoma of the bladder is unusual, occurring most often in the presence of widespread systemic metastases. We report on a patient who presented with an isolated cerebellar metastasis and recurrent carcinoma of the bladder, after treatment with local excision and intravesical thiotepa. Further evaluation failed to demonstrate other distant metastases. Excision of the cerebellar lesion revealed transitional cell carcinoma identical to the original bladder tumor. In a review of the literature, we found reports of two similar patients in whom a solitary cerebellar lesion was the first sign of metastasis from carcinoma of the bladder; neither patient had evidence of other distant metastases, and neither previously had received systemic chemotherapy. These observations indicate that central nervous system metastasis from carcinoma of the bladder, while rare, should be considered in the differential diagnosis of solitary intracerebellar lesions in such patients. 相似文献
52.
A Pollack H Leiba D Soroker T Ezri P Merlis M Oliver 《Journal of pediatric ophthalmology and strabismus》1991,28(6):333-337
The increasing range of indications for laser treatment and the development of new modalities of lasering have led to a growing tendency to extend this type of treatment to the pediatric population. Problems of compliance in this age group often necessitate the use of general anesthesia. This report describes the operative technique used in 11 children (13 eyes) under the age of 13 years, all of whom underwent laser treatment under general anesthesia for a variety of ocular conditions. Argon or krypton laser photocoagulation was performed in eight children (10 eyes), seven of whom were treated for various retinal pathologies and one for an iris cyst. The other three children underwent Nd:YAG posterior capsulotomy for secondary cataract. 相似文献
53.
54.
Wolfram Grimm Jens Winzenburg Ursula Knop Jürgen Hoffmann Volker Menz Frank Grote Bernhard Maisch 《Annals of noninvasive electrocardiology》1997,2(1):20-26
Objective: This prospective study was designed to compare incidence and clinical significance of ventricular late potentials between patients with idiopathic dilated cardiomyopathy (IDC) and postinfarct patients (CAD) using exactly the same method of signal-averaged electrocardiography (SAECG) in both patient groups. Methods: Time-domain analysis of SAECG was performed in 120 consecutive patients with IDC, 120 patients with CAD, and 60 healthy controls. Ventricular late potentials were detected in 27 of 120 patients with IDC (23%) compared to 41 of 120 patients with CAD (34%; P < 0.05). Results: Ventricular late potentials were found in 2 of 60 controls (3%). During 15 ± 7 months follow-up, serious arrhythmic events occurred in 17 of 120 patients with IDC (14%) and in 13 of 120 patients with CAD (11%). The sensitivity of ventricular late potentials for future arrhythmic events was 35% for IDC compared to 77% for CAD (P < 0.05). The positive predictive value of late potentials detected by time-domain analysis was 22% for IDC versus 24% for CAD (P = ns). Conclusion: In this selected patient population with IDC and CAD, time-domain analysis of SAECG revealed a lower incidence of ventricular ate potentials in patients with IDC as compared to postinfarct patients. Whereas ventricular late potentials had a high sensitivity but a low positive predictive value for identification of postinfarct patients with serious arrhythmic events during follow-up, both sensitivity and positive predictive value of ventricular late potentials for future serious arrhythmic events were low in the setting of IDC. 相似文献
55.
M F Oliver 《British medical bulletin》1990,46(4):865-872
To my mind, there are more unresolved problems regarding lipids and cardiovascular diseases than those which have been settled. While this may seem disappointing after 40 years of intensive research, the progress which has been made is remarkable and impressive. It is appropriate, therefore, to begin an introduction by outlining the issues which have been resolved and which are more or less internationally agreed. In doing so, I shall deliberately not digress into causes of coronary heart disease (CHD) other than lipids, even though other influences may be as or more important in relation to its pathogenesis. 相似文献
56.
Identification of tumour-specific peptide(s) hidden within the groove of human leucocyte antigens is a crucial prerequisite for peptide vaccine therapy. Conventionally, the peptide(s) are isolated by mild acid extraction (MA) technique followed by sequential ultra-filtrations. Here we describe a new approach for peptide isolation using the immunobead purification (IB-P) technique in conjunction with reverse-phase high-performance liquid chromatography. The obtained data were validated by SDS-PAGE followed by the silver staining technique. The results can be summarised as follows: (1) Comparison of class I-associated peptides isolated from a bladder cell line before and after the correction of class I antigens by gene transfection followed by IB-P technique showed the presence of peptides only from the class I-corrected cells. The data were confirmed using the silver staining technique as a way of detecting individual peptide bands. (2) Whilst peptides could be isolated by both techniques, the MA method led to the isolation of peptides from both class I-negative and class I-positive Fen cell lysates. (3) The IB-P approach could be used for isolation of class I-associated peptides from a normal kidney tissue. The data showed the high efficiency of the IB-P approach for isolation of class I-associated peptides. Unlike the MA technique, where the presence of non- class I-associated peptides was a problem, the IB-P approach isolated only peptides associated with the class I antigens. In addition, the data showed the feasibility of extracting peptides from tissue fragments by the IB-P method. The approach presented here may assist the future development of peptide vaccine therapy in urological cancers. 相似文献
57.
Summary Experimental testicular torsion must be used for certain studies of clinical relevance, but most experimental models either do not provide hemodynamic alteration comparable to the clinical situation or cannot guarantee reproducibility. Using a rat model arterial perfusion and hemorrhagic infarction were correlated to the degree of both intra- and extravaginal testicular torsion. Arterial inflow was measured sequentially with radiolabelled microspheres, hemorrhagic infarction was judged by the increase of testicular weight. Maximal hemorrhagic infarction and reproducible values were found when the spermatic cord was twisted togehter with the tunica vaginalis for 360°–540°. 相似文献
58.
In vitro cytolysis of primitive neuroectodermal tumors of the posterior fossa (medulloblastoma) by lymphokine-activated killer cells 总被引:2,自引:0,他引:2
R E George W G Loudon R P Moser J M Bruner P A Steck E A Grimm 《Journal of neurosurgery》1988,69(3):403-409
Short-term stimulation of nonantigen-primed peripheral blood mononuclear leukocytes with interleukin-2 generates a population of oncolytic effectors designated "lymphokine-activated killer" (LAK) cells. These LAK cells express potent lytic activity against a wide spectrum of fresh or cultured autochthonous (patient's own) and allogeneic (unrelated) tumors, yet specifically spare normal tissues. In this study, cells derived from primitive neuroectodermal tumors of the posterior fossa (PNET-PF) were examined for their sensitivity to LAK cytolysis utilizing an in vitro 4-hour chromium-51-release assay. Five early-passage cell lines, derived from primary PNET-PF, demonstrated significant sensitivity to LAK cell cytolysis. Lysis was equally effective in culture medium and cerebrospinal fluid. Three freshly excised PNET-PF exhibited similar susceptibility to lysis by autochthonous LAK cells. Greatly increased expansion of LAK cell cultures could be achieved by short-term stimulation with monoclonal anti-CD3 antibodies in addition to interleukin-2 activation. These findings constitute the preliminary in vitro foundations for potential intrathecal adoptive immunotherapy of PNET-PF with LAK cells. 相似文献
59.
High mol. wt genomic DNA from a genetically dominant aryl hydrocarbonhydroxylase (AHH)-deficient mutant cell line derived from themouse hepatoma cell line Hepa-1 was used to transfect the parentcell line. AHH-deficient transfectants were recovered followingsingle-step selection in medium containing the carcinogen benzo(a)pyrene.The transfectants arose at a frequency of 2 x 107. Thisfrequency was at least 4-fold greater than the frequency ofspontaneous forward mutation in this cell line. In another setof experiments, dominant mutant DNA was co-transfected alongwith the selectable plasmid pSV2ecogpt into parental Hepa-1cells. The frequency of co-transfection was determined to be3 x 108. This frequency was 150 times greater than thatexpected on the basis of coincident but unrelated spontaneousmutation and plasmid uptake. Both types of transfectants werejudged, following somatic cell hybridizations, to possess thedominant phenotype of the mutant cell line, demonstrating thata trans-acting dominant negative regulator of AHH was transferredin these experiments. DNA transfection should therefore providea means for the molecular cloning of the gene that encodes thedominant regulator. 相似文献
60.
Summary Respiratory burst develops in myeloid blast cells if they differentiate functionally along the monocytic or granulocytic lineage. Using the nitroblue tetrazolium (NBT) assay we studied the effects of recombinant human granulocyte/macrophage colony stimulating factor (rhuGM-CSF), rhuG-CSF and rhuM-CSF on development of respiratory burst activity in primary blast cells from patients with myeloid leukemia. Assessing suspension cultures containing cells from patients with acute myeloid leukemia (AML, n=13) or myeloidblast crisis (myBC) of chronic myeloid leukemia (CML, n=5) it was found that the percentage of NBT positive cells was increased by at least 20% as compared to control cultures by rhuGM-CSF in 6/17 cases, by rhuG-CSF in 7/17 cases and by rhuM-CSF in 0/16 cases, representing in responders a mean increase of 267% and 270% in the absolute number of NBT positive cells by rhuGM-CSF and rhuG-CSF, respectively. Morphological examination of cultured cells from responders, as compared to controls, showed decreased blast cell content but generally no evidence of terminal differentiation. The demonstration of Auer rods in NBT positive cells indicates that respiratory burst developed in a leukemic clone. These findings may be of physiological, pathophysiological and clinical relevance. 相似文献