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71.
OBJECTIVE: To evaluate a novel fixation system for reproducible radiography in edentulous patients. METHODS: A conventional extra-oral fixation system was modified with a filmholder and adjustable scales. For measuring reproducibility and angulation errors two rods and two balls were fixed on the alveolar crests of the maxilla and the mandible and angular variations were measured. One hundred radiographs of a conventional phantom were taken by one of the authors and by ten dental students. The angular disparity was calculated and intra- and interoperator precision determined. RESULTS: The average time taken to assemble the fixation system was 4 min. The 95% confidence interval for precision of the single operator was less than 2.5 degrees in both the maxilla and mandible. The 95% confidence interval for precision of the ten students was less than 2.2 degrees for the maxilla and 2.7 degrees for the mandible. There was no significant difference (P>0.05) in interoperator precision. CONCLUSION: The novel extra-oral fixation system appears to be a potential means of obtaining reproducible radiographs of edentulous patients.  相似文献   
72.
We describe a method to label gamma-aminobutyric acid (GABA)A receptors on the surface of living hippocampal neurons in primary culture, and we compare the distribution of receptors with that of active synapses. To visualize GABAA receptors, the affinity-purified antibody beta3(1-13), recognizing the extracellular N-termini of the GABAA receptor beta2- and beta3-subunits, was used in combination with fluorescent secondary antibodies. The beta2- and beta3-subunits belong to the predominant GABAA receptor subunits in the hippocampus. As expected for aggregates of GABAA receptors in the somato-dendritic plasma membrane, a patchy staining pattern similar to that seen by labelling neurons after fixation was obtained. An antiserum recognizing an intracellular epitope of GABAA receptor beta3-subunits did not label the receptors in living neurons. Whole-cell recordings of GABA-evoked Cl - currents were not affected after decorating GABAA receptors with antibody beta3(1-13). Combining the staining of GABAA receptors with the labelling of active presynaptic terminals with the fluorescent dyes FM1-43 or FM4-64, consistently resulted in the detection of GABAA receptor clusters that were not located at active synapses. These amounted to approximately 50% of all labelled GABAA receptor clusters. GABAA receptor clusters that were not associated with active presynaptic terminals partially colocalized with the synaptic vesicle marker protein sv2, while another fraction had no presynaptic counterpart at all. These findings suggest the presence of presynaptically silent GABAergic synapses in cultured hippocampal neurons. They also indicate that for the maintenance of GABAA receptor aggregates, the release of GABA from an opposing active terminal is not essential.  相似文献   
73.
OBJECTIVE: Implanon (NV Organon, Oss, The Netherlands) was released in the United Kingdom towards the end of 1999. This survey elicited the experiences of women who had the new implant inserted in three family planning services in North Trent, UK during the first year after its introduction. METHOD: A previously piloted questionnaire was sent to all Implanon users who had the devices fitted in the three services between December 1999 and December 2000. Returned questionnaires were analyzed. RESULTS: Health-care providers and friends or family were the main sources of information about the single-rod contraceptive implant for the survey population. Women considered themselves informed about the method prior to insertion irrespective of whether they continued to use the method or requested early removal. Ease of use was the most common reason for choosing Implanon and one of the best-liked features. Bleeding irregularities were the most commonly reported side-effect, followed by weight gain, moods and headaches. Bleeding problems led to the majority of removal requests; the wish for pregnancy was not stated at all. The single-rod implant compared favorably with most responders' experiences with other methods of contraception. Further research into motivation and perceptions regarding modern contraceptives may be required in different populations.  相似文献   
74.
PURPOSE: To evaluate safety and preliminary efficacy of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy (RT) in unresectable head and neck cancer patients. Secondary end points were the measurement of h-R3 serum levels and the assessment of the potential mechanisms of antitumor effect on patient biopsies. Anti-idiotypic response to h-R3 was assessed. To predict pharmacologic effect, a mathematical model for antibodies recognizing antigens expressed in tumors and normal tissues was built. PATIENTS AND METHODS: Twenty-four patients with advanced carcinomas of the head and neck received six once-weekly infusions of h-R3 at four dose levels in combination with RT. Pretreatment tumor biopsies were obtained to evaluate epidermal growth factor receptor expression as an enrollment criterion. Second biopsies were taken to evaluate the proliferative activity and angiogenesis in comparison with the pretreatment samples. Patient serum samples were collected to measure h-R3 levels and anti-idiotypic response. RESULTS: The combination of h-R3 and RT was well tolerated. Antibody-related adverse events consisted in infusion reactions. No skin or allergic toxicity appeared. Overall survival significantly increased after the use of the higher antibody doses. Immunohistochemistry studies of tumor specimens before and after treatment revealed that antitumor response correlated with antiproliferative and antiangiogenic effect. One patient developed antibodies to h-R3. The mathematical model predicted that the maximum difference between the area under the curve in tumors and normal tissues is reached when the antibody has intermediate affinity. CONCLUSION: h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms.  相似文献   
75.
76.
Zusammenfassung Die Messung otoakustischer Emissionen (OAE) wird für H?rscreeninguntersuchungen von Neugeborenen auf Empfehlung der NIH Consensus Conference im Jahre 1993 in den USA und Europa eingesetzt. Obwohl diese Messungen gegenüber anderen objektiven Me?verfahren einfacher durchzuführen sind, erfordert die Bedienung des Systems und die Interpretation der Ergebnisse speziell geschultes Personal. Ein allgemeines objektives H?rscreening in Deutschland hat sich bisher weder bei Neugeborenen noch bei Risikokindern durchgesetzt, obwohl es wünschenswert w?re, Kinder mit angeborener Innenohrschwerh?rigkeit (Inzidenz: 1–6 von 1000) m?glichst früh zu erfassen, zu therapieren und zu rehabilitieren. Der Echosensor bietet die M?glichkeit, TEOAE-Messungen mit kurzer Me?zeit durchzuführen und automatisiert zu bewerten. Sie k?nnten auch von angelerntem Personal durchgeführt werden. Um die Ergebnisse des Echosensors mit denen des konventionellen TEOAE-Me?ger?ts ILO88 zu vergleichen, wurden OAE-Messungen an 111 Neugeborenen von audiologisch geschulten Personen durchgeführt. Im Rahmen dieser Pilotstudie wurden Reliabilit?t und Validit?t der Messungen im Vergleich zum Goldstandard der Hirnstammaudiometrie bestimmt. Es zeigte sich eine sehr hohe übereinstimmung (Sensitivit?t 100%, Spezifit?t 93,3%) zwischen den Ergebnissen beider Methoden. Somit steht mit dem Echosensor ein OAE-Me?verfahren zur Verfügung, das eine hohe Sensitivit?t und Spezifit?t aufweist und zu einfach bedienen ist. Dieses Ger?t k?nnte einem fl?chendeckenden Einsatz des H?rscreenings in Deutschland den Weg ebnen. Eingegangen am 22. Dezember 1996 Angenommen am 9. Juli 1998  相似文献   
77.
Huntington's disease is characterised by hyperkinetic movements, mainly chorea, cognitive dysfunction, and psychiatric abnormalities. Non-dopa responsive parkinsonism occurs in the later stages of choreic disease or as the predominant feature of juvenile patients (Westphal variant). Late onset Huntington's disease presenting as levodopa responsive parkinsonism is rare. A series of four patients with late onset Huntington's disease presenting as levodopa responsive parkinsonism and cardiovascular dysautonomia, initially misdiagnosed as multiple system atrophy (MSA) in three patients, is reported. Levodopa treatment did not unmask significant chorea. These cases suggest the presence of a distinct phenotypic variant of Huntington's disease to be added to the differential diagnosis of other akinetic rigid syndromes.  相似文献   
78.
Extraosseous Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is a rare soft tissue tumor of childhood usually found in the extremities. The authors present the case of a 17-year-old girl who presented with right flank pain and hematuria and during operation was found to have a right ureteral mass. The histopathologic, immunohistochemical, ultrastructural, and cytogenetic characteristics of the excised mass were consistent with extraosseous ES/PNET. This is the first known reported case of extraosseous ES/ PNET of the ureter. The pathologic features and clinical management of this case, as well as a review of the literature, are presented.  相似文献   
79.
The auditory midbrain implant (AMI) is a new central auditory prosthesis designed for penetrating stimulation of the human inferior colliculus. The major group of candidates for the AMI consists of neurofibromatosis type 2 (NF2) patients who develop neural deafness because of growth and/or surgical removal of bilateral acoustic neuromas. Because of the absence of a viable auditory nerve, these patients cannot benefit from cochlear implants. An alternative solution has been the auditory brainstem implant (ABI), which stimulates the cochlear nucleus. However, speech perception performance in NF2 ABI patients has been limited. The fact that the ABI is able to produce high levels of speech perception in nontumor patients (with inaccessible cochleae or posttraumatic damage to the cochlear nerve) suggests that limitations in ABI performance in NF2 patients may be associated with cochlear nucleus damage caused by the tumors or the tumor removal process. Thus, stimulation of the auditory midbrain proximal to the damaged cochlear nucleus may be a better alternative for hearing restoration in NF2 patients. We propose the central nucleus of the inferior colliculus (ICC) as the potential site. A penetrating electrode array aligned along the well-defined tonotopic gradient of the ICC should selectively activate different frequency regions, which is an important elementfor supporting good speech understanding. The goal of this article is to present the ICC as an alternative site for an auditory implant for NF2 patients and to describe the design of the first human prototype AMI. Practical considerations for implementation of the AMI will also be discussed.  相似文献   
80.
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