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91.
The environmental health-related relevance of cyanobacteria is primarily related to their ability to produce a wide range of toxins, which are known to be hazardous to many organisms, including human beings. The occurrence of cyanobacterial blooms has been related to eutrophic surface water. In the bloom-forming process the levels of phosphorus and nitrogen have been well documented but information regarding concentrations of other chemicals (inorganic, organo-metallic, and organic) is still incipient. Several contaminants, like trace metals, elicit a variety of acute and chronic toxicity effects, but cyanobacteria also have the capability to accumulate, detoxify, or metabolize such substances, to some extent. The role of cyanobacterial exudates has been proved a means of both nutrient acquisition and detoxification. In addition, cyanobacteria are effective biological metal sorbents, representing an important sink for metals in aquatic environment. Understanding the fundamental physicochemical mechanisms of trace metal bio-uptake by cyanobacteria in natural systems is a step towards identifying under what conditions cyanobacterial growth is favored and to ascertain the mechanisms by which blooms (and toxin production) are triggered. In this review the cyanobacterial interactions with metals will be discussed, focusing on freshwater systems. 相似文献
92.
Vasconcelos Camila Vilela Costa Alan Carlos Müller Caroline Castoldi Gustavo Costa Andréia Mendes de Paula Barbosa Kássia Rodrigues Arthur Almeida da Silva Adinan Alves 《Ecotoxicology (London, England)》2020,29(2):203-216
Ecotoxicology - Common bean (Phaseolus vulgaris) cultivation occurs mainly in regions with acidic soils, where high aluminum (Al) concentration is a major constraint to crop production. In this... 相似文献
93.
Fernando Tadeu Vasconcelos Amaral Paulo Henrique Manso André Schmidt Ricardo Nilson Sgarbieri Walter Villela de Andrade Vicente Clovis Carbone Junior Jane Somerville 《Brazilian Journal Of Cardiovascular Surgery》2015,30(3):373-379
During the last decades, advances in diagnosis and treatment of congenital heart
disease have allowed many individuals to reach adulthood. Due mainly to the great
diagnostic diversity and to the co-morbidities usually present in this age group,
these patients demand assistance in a multidisciplinary facility if an adequate
attention is aimed. In this paper we reviewed, based in the international literature
and also on the authors’ experience, the structural conditions that should be
available for these patients. We highlighted aspects like the facility
characteristics, the criteria usually adopted for patient transfer from the
paediatric setting, the composition of the medical and para- medical staff taking
into account the specific problems, and also the model of outpatient and in-hospital
assistance. We also emphasized the importance of patient data storage, the
fundamental necessity of institutional support and also the compromise to offer
professional training. The crucial relevance of clinical research is also approached,
particularly the development of multicenter studies as an appropriate methodology for
this heterogeneous patient population. 相似文献
94.
95.
Hypovitaminosis D has been reported in tropical countries, but this hormone has seldom been studied in Brazil. Our purpose
was to study the prevalence of hypovitaminosis D in patients hospitalized in internal medicine wards in Southern Brazil. Possible
associated factors were studied. We studied 81 adult patients in early spring. Mean serum 25(OH)D was 12±8.57 ng/mL; hypovitaminosis
D was severe (<10 ng/mL) in 27 (33.3%) patients, and moderate (≥10 ng/mL and <20 ng/mL) in 36 (44.5%) patients. Clinical evaluation
did not yield any data associated with hypovitaminosis D. Serum 25(OH)D levels of up to 20 ng/mL were associated with decreased
mean serum total calcium (p=0.001), ionized calcium (p=0.01), and phosphorus (p=0.044) levels, and increased mean serum PTH level (p=0.001). In a multiple regression model, serum PTH level was independently affected by serum total calcium (p=0.01), phosphorus (p=0.009), and albumin (p=0.009) levels. Hypovitaminosis D patients had lower mean serum albumin levels (p=0.004), and serum 25(OH)D levels were directly correlated to serum albumin levels (p<0.0001). Albumin influenced independently PTH response to hypovitaminosis D; normoalbuminemic hypovitaminosis D patients
had higher mean serum PTH than hypoalbuminemic patients. Conclusion: Hypovitaminosis D prevalence was very high in medical
inpatients in Southern Brazil, in early spring. Nevertheless, secondary hyperparathyroidism was less intense in hypoalbuminemic
hypovitaminosis D patients suggesting that in these patients free serum 25(OH)D was closer to normal. 相似文献
96.
Eva Y.F. Pang Shirley S.M. Fong Mimi M.Y. Tse Eric W.C. Tam Shamay SM Ng Billy C.L. So 《Journal of Physical Therapy Science》2015,27(6):1839-1845
[Purpose] This study investigated the intra-rater, inter-rater and test-retest
reliability of the sideways step test (SST), its correlation with other indicators of
stroke-specific impairment, and the cut-off count best discriminating subjects with stroke
from their healthy counterparts. [Subjects and Methods] Forty-three subjects with chronic
stroke and 41 healthy subjects older than 50 years participated in this study. The SST was
administered along with the Fugl-Meyer motor assessment for the lower extremities
(FMA-LE), the five-times sit to stand (5TSTS) test, the Berg Balance Scale (BBS), the
movement velocity (MVL) by the limits of stability (LOS) test, the ten-metre walk (10mW)
test, the timed “Up and Go” (TUG) test and the Activities-specific Balance Confidence
(ABC) scale. [Results] The SST showed good to excellent intra-rater, inter-rater and
test-retest reliability. The SST counts correlated with 5TSTS times, 10mW times, TUG
times, and the FMA-LE and BBS scores. SST counts of 11 for the paretic leg and 14 for the
non-paretic leg were found to distinguish the healthy adults from subjects with stroke.
[Conclusion] The sideways step test is a reliable clinical test, which correlates with the
functional strength, gait speed, and functional balance of people with chronic stroke.Key words: Balance, Stroke, Rehabilitation 相似文献
97.
Silvana Daher Costa Geraldo Bezerra da Silva Jr. Camilla Neves Jacinto Lorena Vasconcelos Mesquita Martiniano Yago Sucupira Amaral Fernando Jose Villar Nogueira Paes Maria Luiza De Mattos Brito Oliveira Sales Ronaldo de Matos Esmeraldo Elizabeth De Francesco Daher 《The American journal of tropical medicine and hygiene》2015,93(2):394-396
Few studies have focused on Rift Valley fever virus (RVFV) transmission in less arid, transitional landscapes surrounding known high-risk regions. The objective of this study was to identify evidence of RVFV exposure in Bodhei Village in a forested area at the edge of the RVFV-epidemic Garissa region. In a household cluster-based survey conducted between epidemics in early 2006, 211 participants were enrolled. Overall seroprevalence for anti-RVFV was high (18%) and comparable with rates in the more arid, dense brush regions farther north. Seroprevalence of adults was 28%, whereas that of children was significantly lower (3%; P < 0.001); the youngest positive child was age 3 years. Males were more likely to be seropositive than females (25% versus 11%; P < 0.01), and animal husbandry activities (birthing, sheltering, and butchering) were strongly associated with seropositivity. The results confirm that significant RVFV transmission occurs outside of recognized high-risk areas and independent of known epidemic periods. 相似文献
98.
Paulo Roberto Santos Diego Levi Silveira Monteiro Paulo Henrique Alexandre de Paula Vicente Lopes Monte Neto Maria Leilah Ponte Monte Coelho Cecília Costa Arcanjo Sânkia Maria Lopes Aragão Camila Barbosa Gondim Janaína Teixeira Pereira Carneiro Tapeti Hyngridd Soares Mendes Luise Vasconcelos Vieira Rita de Cássia Parente Prado 《Nephrology (Carlton, Vic.)》2015,20(8):519-522
99.
Ana Martins Figueiredo Pedro Barbacena Ana Russo Silvia Vaccaro Daniela Ramalho Andreia Pena Aida Pires Lima Rita Rua Ferreira Marta Alves Fidalgo Fatima El-Marjou Yulia Carvalho Francisca Ferreira Vasconcelos Ana-Maria Lennon-Dumnil Danijela Matic Vignjevic Claudio Areias Franco 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(18)
100.
Tesh RB Guzman H da Rosa AP Vasconcelos PF Dias LB Bunnell JE Zhang H Xiao SY 《The Journal of infectious diseases》2001,183(10):1431-1436
This report describes the clinical laboratory findings in golden hamsters experimentally infected with yellow fever (YF) virus. An accompanying paper describes the pathologic findings. Following intraperitoneal inoculation of a virulent strain of YF virus, hamsters developed a high-titered viremia (up to 109/mL) lasting 5--6 days and abnormal liver function tests. YF hemagglutination-inhibiting antibodies appeared 4 or 5 days after infection, often while viremia was still present. The mortality rate in YF-infected hamsters was variable, depending on the virus strain and the age of the animals. Clinical and pathologic changes in the infected hamsters were very similar to those described in experimentally infected macaques and in fatal human cases of YF, which indicates that the golden hamster may be an excellent alternative animal model, in place of nonhuman primates, for research on the pathogenesis and treatment of YF and other viscerotropic flavivirus diseases. 相似文献