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71.
R. J. Wechsler Mark E. Schweitzer David Karasick Diane M. Deely William Morrison 《Skeletal radiology》1998,27(1):1-6
Since the degree of comminution, fracture alignment, and articular congruity of intra-articular calcaneal fractures are important
determinants in surgical treatment and patient prognosis, we review helical computed tomographic (CT) technique and features
for detecting and assessing the extent of acute calcaneal fractures. Helical CT can be used to classify these fractures and
facilitate the surgeon’s understanding of the anatomy and position of the fracture components in all orthogonal planes independently
of the patient’s condition, foot placement in the CT gantry, or other injuries. 相似文献
72.
73.
Rosenberg Leonard S. Hostetler Cheryl K. Wagenknecht Dietmar M. Aunet Diane A. 《Pharmaceutical research》1988,5(8):514-517
Esmolol hydrochloride degrades in aqueous solutions by the hydrolysis of a labile aliphatic carboxy-ester group. The products are methanol and ASL-8123. The resulting aliphatic carboxylic acid moiety (ASL-8123) has a pK of 4.80, which is within 1 pH unit of the pH of the formulation. ASL-8123 therefore acts as a secondary buffer and minimizes the change in pH due to degradation. Equations are presented to calculate the change in the pH when the primary degradation product acts as a secondary buffer. This information can be used in the development of a parenteral product to predict, a priori, the concentration of buffer necessary for optimal pH maintenance. This knowledge can reduce the number of formulation screens required to determine the necessary buffer capacity for optimal drug stability. 相似文献
74.
75.
In many animal studies, acute treatment with the novel anxiolytic agent buspirone exhibits only minimal anxiolytic efficacy (i.e., increases in punished responding) when compared to benzodiazepines and barbiturates. The present studies examined the effects of acute pre-test challenges with buspirone in subjects receiving chronic post-test buspirone or saline treatments. Chronic post-test treatment with buspirone (4 mg/kg/day for 4 weeks, followed by 8 mg/kg/day for 12 weeks) did not significantly affect CSD behavior. Consistent with previous reports, acute pre-test administration of buspirone (0.125–2 mg/kg, IP) to subjects receiving chronic post-test saline treatment resulted in only a modest anti-conflict effect in the CSD paradigm (approximately ten shocks over control). In contrast, subjects chronically treated with buspirone exhibited a dramatically greater anti-conflict effect following acute challenge with buspirone (up to 40 shocks over control). These data are consistent with the hypothesis that the full anxiolytic efficacy of buspirone requires repeated administration. 相似文献
76.
Stanley MA Beck JG Novy DM Averill PM Swann AC Diefenbach GJ Hopko DR 《Journal of consulting and clinical psychology》2003,71(2):309-319
This study addressed the efficacy of cognitive-behavioral therapy (CBT), relative to minimal contact control (MCC), in a sample of 85 older adults (age 60 years and over) with generalized anxiety disorder (GAD). All participants completed measures of primary outcome (worry and anxiety), coexistent symptoms (depressive symptoms and specific fears), and quality of life. Results of both completer and intent-to-treat analyses revealed significant improvement in worry, anxiety, depression, and quality of life following CBT relative to MCC. Forty-five percent of patients in CBT were classified as responders, relative to 8% in MCC. Most gains for patients in CBT were maintained or enhanced over 1-year follow-up. However, posttreatment scores for patients in CBT failed to indicate return to normative functioning. 相似文献
77.
Matsika-Claquin MD Massanga M Ménard D Mazi-Nzapako J Ténegbia JP Mandeng MJ Willybiro-Sacko J Fontanet A Talarmin A 《Journal of medical virology》2004,72(3):358-362
A sentinel serosurveillance study was conducted in Central African Republic to estimate the prevalence of HIV seropositivity in the general adult population in each province so that the public health authorities can target HIV prevention programmes to the priority areas. Blood samples were collected from women attending 48 antenatal clinics in urban and rural areas of the Central African Republic. These samples were tested for HIV antibodies in an anonymous and unlinked manner using strategy II recommended by WHO. The data were extrapolated to all women of reproductive age in Central African Republic by use of a parity-based adjustment involving the application of correction factors to the observed prevalence rates. A total of 9,305 pregnant women were recruited from November 2001 to October 2002. HIV seroprevalence was high in all age groups (12% in the less than 20 year age group to 17% in the 25-29 year age group). The median prevalence of HIV in antenatal clinics was similar for rural areas, for Bangui and for other urban areas (16.5, 15.0, and 12.5% respectively). Adjustment for parity and fertility pattern increased the prevalence of HIV in all antenatal clinics except in Bangui. This first national study of HIV prevalence in Central African Republic revealed that the HIV epidemic is continuing to spread in both urban and rural areas. Thus, efforts to reduce transmission should be made in every part of the country. 相似文献
78.
79.
The data for 197 mother-infant pairs from two longitudinal studies were analyzed to assess relations between maternal attachment representations; atypical maternal behavior, coded with a new tool. Atypical Maternal Behavior Instrument for Assessment and Classification (AMBIANCE), and infant attachment. Both maternal and infant attachment were systematically related to atypical maternal behavior: mothers who were Unresolved on the Adult Attachment Interview and those whose infants were disorganized in the Strange Situation Procedure engaged in more atypical behaviors than those who were not Unresolved and whose infants showed organized patterns of attachment, respectively. Regression analyses indicated that when tested as a mediator, atypical maternal behavior as measured on the AMBIANCE did not reduce the association between maternal Unresolved status and infant disorganized attachment. This may, in part, reflect the fact that our low-risk sample did not include enough cases in the risk categories. These data provide preliminary empirical validation for the AMBIANCE and strengthen the evidence for links between atypical maternal behavior and disorganized attachment but indicate that in addition to maternal attachment representations, other factors must contribute to atypical maternal behavior. 相似文献
80.
Assessment of the epidemic potential of a new strain of rotavirus associated with the novel G9 serotype which caused an outbreak in the United States for the first time in the 1995-1996 season 下载免费PDF全文
Clark HF Lawley DA Schaffer A Patacsil JM Marcello AE Glass RI Jain V Gentsch J 《Journal of clinical microbiology》2004,42(4):1434-1438
Rotavirus causes severe morbidity in developed countries and frequent deaths (> or = 500,000 per year) in less-developed countries. Historically, four serotypes--G1, G2, G3, and G4-have predominated; they are distinguished by one of two surface neutralization antigens (VP7). However, in 1983 and 1984 we described a new rotavirus serotype, designated G9, in five children hospitalized for diarrhea in Philadelphia, Pa. G9 rotavirus was not identified again in the Western Hemisphere until it caused ca. 50% of the rotavirus disease detected in Philadelphia in the 1995-1996 season. This outbreak allowed us to question whether a rotavirus strain completely new to a well-studied community would target either very young infants or older children, cause especially severe disease, or completely displace previously extant serotypes. We observed a significant excess of G9 infections in younger infants (especially in those < 6 months old) that might be attributed to the lack of G9-specific antibodies in mothers. Of further note, six of the seven oldest patients with rotavirus diarrhea were infected with the G9 strains (not significant). However, the age distribution of children with rotavirus did not differ over a 5-year study period regardless of the infecting serotype. Patients with diarrhea associated with G9 strains did not have disease more severe than that caused by the G1, G2, or G3 serotype. G9 strains did not displace the other serotypes but were virtually completely replaced by G1 or G2 serotypes in the three subsequent rotavirus seasons. We conclude that the abrupt appearance of this novel rotavirus serotype did not present a special threat to public health in the community. 相似文献