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991.
OBJECTIVE: As the epidemic of overweight increases among youth, research needs to examine factors that may influence children's participation in weight-related health behaviors. This study examined overweight children's perceived barriers to and support for physical activity compared with nonoverweight children. RESEARCH METHODS AND PROCEDURES: Barriers to and support for physical activity were examined among 84 overweight children attending a summer fitness camp or a university-based weight loss clinic. Barriers and support levels were then compared with those of 80 nonoverweight children of a similar age range. RESULTS: Body-related barriers were the most predominant barrier type among overweight youth, especially among overweight girls. Overweight children, particularly girls, reported significantly higher body-related, resource, and social barriers to physical activity compared with nonoverweight children and lower levels of adult support for physical activity. DISCUSSION: Overweight children may be particularly vulnerable to body-related barriers to physical activity, and reducing such barriers may serve as physical activity intervention points most relevant for overweight youth. Future interventions may also benefit from enhancing support for physical activity from adults and peers. 相似文献
992.
Antimicrobial resistance to penicillin and macrolides in Streptococcus pneumoniae has increased in the United States over the past decade. Considerable geographic variation in susceptibility necessitates regional resistance tracking. Traditional active surveillance is labor intensive and costly. We collected antibiogram reports from North Carolina hospitals and assessed pneumococcal susceptibility to multiple agents from 1996 through 2000. Susceptibility in North Carolina was consistently lower than the national average. Aggregating antibiogram data is a feasible and timely method of monitoring regional susceptibility patterns and may also prove beneficial in measuring the effects of interventions to decrease antimicrobial resistance. 相似文献
993.
Stein MB 《Psychopharmacology bulletin》2003,37(Z1):97-107
Social anxiety disorder frequently begins in early life and is associated with the subsequent development of comorbid conditions such as depressive and substance use disorders. Social anxiety disorder, particularly the generalized subtype, is characterized by marked impairment in numerous functional domains, including education and social relations. Paroxetine, the first medication to receive an indication in the United States for the treatment of social anxiety disorder, has been shown to be effective in 50% to 60% of patients. The mechanism of action of paroxetine in the treatment of social anxiety disorder is at present unclear. A possible role for early treatment to prevent complications of social anxiety disorder should be explored. 相似文献
994.
OBJECTIVE: To examine the rate of formal substance abuse (SA) treatment in a privately insured population, and the association between cost-sharing, residential treatment, and outpatient SA treatment, we analyzed claims data for 332442 adults in 41 health plans with comprehensive SA treatment benefits. DESIGN: SA treatment utilization during 1999 and the relationship between patient cost-sharing, gender, and SA diagnosis on SA treatment utilization were examined using a cross-sectional retrospective analysis. RESULTS: Only 0.37% (n=1230) of adults had a SA related claim during 1999. Individuals in plans with higher levels of cost-sharing had lower rates of residential SA treatment and specialty SA outpatient treatment compared to individuals in plans with lower cost-sharing, adjusting for age, sex, and SA diagnosis. CONCLUSIONS: Few individuals had SA related claims, raising questions about rates of undocumented treatment, out-of-network treatment, and unmet need for treatment in the privately insured, and its implications for assessing the quality of SA treatment available in private health plans. At a time when levels of cost-sharing are increasing among privately insured individuals, consideration should be given the potential impact of such changes on the treatment of individuals requiring specialty SA treatment. 相似文献
995.
Arrowsmith ER Macon WR Kinney MC Stein RS Goodman SA Morgan DS Flexner JM Cousar JB Jagasia MH McCurley TL Greer JP 《Leukemia & lymphoma》2003,44(2):241-249
The purpose of this study was to better define the clinical features and natural history of peripheral T-cell lymphomas (PTCL) entities included in the Revised European American lymphoma (REAL) classification. Cases of PTCL were retrieved from the records of the Department of Pathology and classified according to the REAL classification. In addition, cases of anaplastic large cell lymphoma (ALCL) were divided into classical, small cell, and primary cutaneous subtypes, and immunostaining for the anaplastic large-cell kinase (ALK) protein was performed on all cases of ALCL. Clinical features, response to therapy and survival were abstracted. Ninety-two cases of PTCL with adequate clinical information were retrieved. There were 40 cases of ALCL (30 classical, 7 small cell variant, 3 primary cutaneous), 28 PTCL, unspecified, 13 angioimmunoblastic T-cell lymphoma and 11 with other entities. The patients had a median age of 48 years with a range of 6-84 and had an estimated overall survival (OS) of 49% and progression-free survival (PFS) of 22% at 5 years. The International Prognostic Index (IPI) was a significant prognostic factor for both progression-free and OS. Histology was a significant predictor of PFS with anaplastic large cell having the best prognosis. ALK expression was not associated with an improved progression-free or overall-survival in patients with systemic T-cell ALCL. In conclusion, the REAL classification describes distinct PTCL entities. The IPI is the most important predictor of progression-free and OS in patients with PTCL. ALK expression may not provide prognostic information for systemic ALCL. 相似文献
996.
Survival rates of patients with early breast cancer in the United Kingdom and in the United States have improved steadily
over the past 15 years. The only way to continue or even accelerate this progress, however, is the discovery and development
of new preventative and therapeutic strategies. With the massive explosion in potential therapeutic strategies becoming available,
in the postgenomic era, better and more representative breast cancer models are urgently required for preclinical trials.
Development of better in vivo models of human breast cancer are thus of crucial importance in the development of new cancer therapeutics. 相似文献
997.
Barrett’s esophagus and Barrett’s carcinoma 总被引:1,自引:0,他引:1
The alarming rise in the incidence of esophageal adenocarcinomas in the Western world has focused interest on so-called Barrett’s
esophagus. Barrett’s esophagus is characterized by specialized intestinal epithelium replacing the normal squamous epithelium
in the distal esophagus and is considered a consequence of long-lasting and severe gastroesophageal reflux disease. A metaplasia-dysplasia-carcinoma
sequence links Barrett’s esophagus with adenocarcinoma of the distal esophagus (Barrett’s cancer). Despite intensive research,
many questions concerning the pathogenesis, diagnosis, and treatment of Barrett’s esophagus and associated adenocarcinoma
are still unanswered. Based on current data, the malignant progression of Barrett’s esophagus cannot be substantially prevented
by medical or surgical therapy for reflux. Although no firm data are available to show that surveillance strategies can reduce
overall mortality from Barrett’s cancer, early detection and cure are possible. Management of Barrett’s esophagus and carcinoma
is reviewed with reference to the sequence of disease from metaplasia to carcinoma. 相似文献
998.
Stein J 《Developmental neuropsychology》2001,20(2):509-534
Learning to read is much more difficult than learning to speak. Most children teach themselves to speak with little or no difficulty. Yet a few years later when they come to learn to read they have to be taught how to do it; they do not pick up reading by themselves. This is because we speak in words and syllables, but we write in phonemes. Syllables do not naturally break down into the sounds of letters and letter units (i.e., phonemes) because these do not correspond to physiologically distinct articulatory gestures (Liberman, Shankweiler, & Studdert-Kennedy, 1967). Alphabetic writing was only invented when people realized that syllables could be artificially divided into smaller acoustically distinguishable phonemes that could be represented by a small number of letters. But these distinctions are arbitrary cultural artifacts, and their mastery was originally confined to a select social class. And until about 100 years ago it did not matter much if the majority of people could not read; the acquisition of reading probably had no serious disadvantages. Reading requires the integration of at least two kinds of analysis (Castles & Coltheart, 1993; Ellis, 1984; Manis, Seidenberg, Doi, McBride-Chang, & Petersen, 1996; Morton, 1969; Seidenburg, 1993). First, the visual form of words, the shape of letters, their order in words, and common spelling patterns, which is termed their orthography, has to be processed visually. Their orthography yields the meaning of familiar words very rapidly without needing to sound them out. But for unfamiliar words, and all words are fairly unfamiliar to the beginning reader, the letters have to be translated into the speech sounds (i.e., phonemes) that they stand for, and then those sounds have to be melded together in inner speech to yield the word and its meaning. Reading exclusively by the phonological route is more time consuming than if words can be accessed directly without requiring phonological mediation. 相似文献
999.
1000.
Nonviral in vivo gene delivery into tumors using a novel low volume jet-injection technology 总被引:1,自引:0,他引:1
The jet-injection technology has developed as an applicable alternative to viral or liposomal gene delivery systems. In this study a novel, low-volume, 'high-speed jet injector' hand-held system was used for the direct gene transfer of naked DNA into tumors. Lewis-lung carcinoma bearing mice were jet-injected with the beta-galactosidase (LacZ), the green fluorescence (GFP) or the human tumor necrosis factor alpha (TNF-alpha) gene carrying vector plasmids. The animals received five jet injections into the tumor at a pressure of 3.0 bar, delivering 3--5 microl plasmid DNA (1 microg DNA/microl in water) per single jet injection. The jet injection of DNA leads to a widespread expression pattern within tumor tissues with penetration depths of 5--10 mm. Analysis of tumor cryosections revealed moderate LacZ or GFP expression at 48 h and strong reporter gene expression 72 h and 96 h after jet injection. The simultaneous jet injection of the TNF-alpha and LacZ carrying vectors demonstrated efficient expression and secretion of both the cytokine, as well as LacZ expression within the tumor 24 h, 48 h, 72 h, 96 h and 120 h after jet injection. These studies demonstrate the applicability of jet injection for the efficient in vivo gene transfer into tumors for nonviral gene therapy of cancer using minimal amounts of naked DNA. 相似文献