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Fitzgerald DW  Marotte C  Verdier RI  Johnson WD  Pape JW 《Lancet》2002,360(9342):1301-1302
Few practical guidelines exist on how to ensure that research participants in less-developed countries understand the consent form before enrollment. In a study of HIV-1 transmission in Haiti, participants were required to pass an oral examination on the contents of the consent form with a passing score of 12/15 (80%) before enrollment. 15 individuals were given information during a single meeting with a physician, and three (20%) passed. 30 subsequent volunteers were given information by a counsellor during three meetings, and 24 (80%) passed. Formal assessment of research participants' comprehension of the consent form should be considered as a routine step in the informed consent process in less-developed countries.  相似文献   
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BACKGROUND: The widely accepted practice of early fracture fixation (EFF) in multiply injured patients has recently been challenged in the presence of head injury. DATA SOURCES: English and German language articles on the subject were searched using Medline. Keywords included head trauma, intracranial trauma, brain injuries, fractures, fracture fixation, timing, femur fracture, and tibia fracture. CONCLUSIONS: The available literature does not provide clear-cut guidance on the management of fractures in the presence of head injuries. The trend is toward a better outcome if the fractures are fixed early. Treatment should therefore be tailored to the individual patient, with the assumption that full neurologic recovery will take place.  相似文献   
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BACKGROUND AND PURPOSE: Antiprotons travel through tissue in a manner similar to that for protons until they reach the end of their range where they annihilate and deposit additional energy. This makes them potentially interesting for radiotherapy. The aim of this study was to conduct the first ever measurements of the biological effectiveness of antiprotons. MATERIALS AND METHODS: V79 cells were suspended in a semi-solid matrix and irradiated with 46.7MeV antiprotons, 48MeV protons, or (60)Co gamma-rays. Clonogenic survival was determined as a function of depth along the particle beams. Dose and particle fluence response relationships were constructed from data in the plateau and Bragg peak regions of the beams and used to assess the biological effectiveness. RESULTS: Due to uncertainties in antiproton dosimetry we defined a new term, called the biologically effective dose ratio (BEDR), which compares the response in a minimally spread out Bragg peak (SOBP) to that in the plateau as a function of particle fluence. This value was approximately 3.75 times larger for antiprotons than for protons. This increase arises due to the increased dose deposited in the Bragg peak by annihilation and because this dose has a higher relative biological effectiveness (RBE). CONCLUSION: We have produced the first measurements of the biological consequences of antiproton irradiation. These data substantiate theoretical predictions of the biological effects of antiproton annihilation within the Bragg peak, and suggest antiprotons warrant further investigation.  相似文献   
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Zusammenfassung Die erh?hten Eisenstoffwechselparameter unseres Patienten bei vorbekannter PCT führten zur Diagnose zweier Mutationen im H?mochromatose-Gen. Er erwies sich als zusammengesetzt heterozygoter Tr?ger der Mutationen Cys282Tyr und His63Asp, die zu einem Verlust bzw. einer Einschr?nkung der Funktion des HFE-Proteins führen. Der Aderlass als symptomatische Monotherapie führte bei unserem Patienten zum Verschwinden der Hautl?sionen und zum Abfall der pathologisch erh?hten Porphyrinausscheidung. Bei der erworbenen Form der PCT sollte deshalb neben der Alkoholanamnese und der Hepatitisserologie auch eine genetische Diagnostik bezüglich der Mutationen im H?mochromatose-Gen durchgeführt werden. Durch das Screening Verwandter von Mutationstr?gern k?nnen au?erdem frühzeitig Personen mit H?mochromatoserisiko erfasst werden.  相似文献   
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The lipid content and the fatty acid pattern were analysed in the abdominal subcutaneous adipose tissue of 241 children aged 2 months to 12 years. The lipid content was found between 63 and 71%.During childhood the portion of saturated fatty acids in the subcutaneous adipose tissue decreases significantly; the unsaturated fatty acid portion, however, increases accordingly. This change in the fatty acid pattern concerning the saturated fatty acids is mainly determined by myristic, palmitic and stearic acids, concerning the unsaturated fatty acids it is determined by palmitoleic, oleic and linoleic acids. The changes during childhood in the percentage of the single fatty acids are described in detail.In addition to the age-dependent development of the fatty acid pattern in the subcutaneous adipose tissue a dependence upon diet will probably exist for stearic, lauric and linoleic acids.The investigations were supported by the Ministerium für Wissenschaft und Forschung — Landesamt für Forschung — des Landes Nordrhein-Westfalen, Federal Republic of Germany  相似文献   
98.
Background:An update of results from the High Risk Protocol ofthe Meta-EICESS Study, conducted at the Pediatric Stem-Cell Transplant Centersof Düsseldorf and Vienna. In order to evaluate a possible therapeuticbenefit after allogeneic SCT in patients with advanced Ewing tumors (AET), wecompared outcome after autologous and allogeneic stem-cell transplantation(SCT). Patients and methods:We analyzed 36 patients treated with themyeloablative Hyper-ME protocol (hyperfractionated total body irradiation,melphalan, etoposide ± carboplatin) between November 1986 and December1994. Minimal follow-up for all patients was five years. All patientsunderwent remission induction chemotherapy and local treatment beforemyeloablative therapy. Seventeen of thirty-six patients had multifocal primaryEwing's tumor, eighteen of thirty-six had early, multiple or multifocalrelapse, one of thirty-six patients had unifocal late relapse. Twenty-six ofthirty-six were treated with autologous and ten of thirty-six with allogeneichematopoetic stem cells. We analyzed the following risk factors, that couldpossibly influence the event-free survival (EFS): number of involved bones,degree of remission at time of SCT, type of graft, indication for SCT, bonemarrow infiltration, bone with concomitant lung disease, age at time ofdiagnosis, pelvic involvement, involved compartment radiation,histopathological diagnosis. Results:EFS for the 36 patients was 0.24 (0.21) ± 0.07.Eighteen of thirty-six patients suffered relapse or died of disease, nine ofthirty-six died of treatment related toxicity (DOC). Nine of thirty-sixpatients are alive in CR. Age 17 years at initial diagnosis (P< 0.005) significantly deteriorated outcome. According to the type ofgraft, EFS was 0.25 ± 0.08 after autologous and 0.20 ± 0.13after allogeneic SCT. Incidence of DOC was more than twice as high afterallogeneic (40%) compared to autologous (19%) SCT, even thoughthe difference did not reach significance (P = 0.08, Fisher's exacttest). Conclusions:Because of the rather short observation period,secondary malignant neoplasm (SMN) may complicate the future clinical courseof some of our patients who are currently viewed as event-free survivors. EFSin AET is not improved by allogeneic SCT due to a higher complication rate.The patient group was to small to analyze for a possiblegraft-versus-tumor effect.  相似文献   
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The potential of 99m-Tc-J001 for the investigation of inflammatory lesions via the targeting of recruited macrophages (Mφ) has already been documented in several experimental models and in human diseases. To achieve a functional imaging of inflammation via Mφ targeting, minimal labeled colloid content and high in vivo stability of 99mTc-J001 are essential. The actual specificity of such scintigraphy is closely dependent upon the radiolabeling of only the J001 molecules available for Mφ targeting. To develop an appropriate radiopharmaceutical kit, optimization of the labeling conditions was achieved from a series of pilot formulations that were evaluated for radiolabeling efficiency and both in vitro and in vivo 99mTc-J001 stability. Colloids were characterized using autocorrelation spectroscopy and multiangle laser-light scattering, radioactive colloid content of the formulations being deduced from biodistribution studies. This work has made possible the definition of a formulation exhibiting a radiolabeling yield >97.0%, associated with in vivo stability and minimal colloid formation, thus greatly enhancing the specificity of such macrophage scintigraphy.  相似文献   
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