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31.
Van de Velde H; De Vos A; Joris H; Nagy ZP; Van Steirteghem AC 《Human reproduction (Oxford, England)》1998,13(11):3160-3164
In human in-vitro fertilization (IVF), the oocytes are surrounded by
cumulus and corona cells at the time of insemination so that their maturity
cannot easily be evaluated. The best IVF results are obtained if the
oocytes are inseminated 2-6 h after retrieval. In the intracytoplasmic
sperm injection (ICSI) procedure, the oocytes are denuded by enzymatic and
mechanical treatment in order to be able to perform the injection. As a
consequence, the nuclear maturity of the oocytes can be evaluated and only
those that have extruded the first polar body are injected. However,
metaphase-II oocytes that have not yet reached cytoplasmic maturity cannot
be recognized. The purpose of this study was to investigate the effect of
different timing of cumulus- corona cell removal and injection on the
outcome of ICSI. For this we allowed the oocytes to complete in-vitro
cytoplasmic maturation in two different culture conditions: (i) surrounded
by their cumulus and corona cells or (ii) totally denuded. We performed
three different studies on sibling oocytes obtained after a standardized
buserelin/human menopausal gonadotrophin (HMG) protocol. We investigated
the effect of early (1-2 h after retrieval) and late (5-6 h after
retrieval) oocyte denudation and injection on the survival and
fertilization of the injected oocytes and on embryo cleavage after
fertilization. We found no statistically significant differences between
early and late injection, indicating that after a standardized
buserelin/HMG protocol the metaphase-II oocytes do not need time for
further cytoplasmic maturation. Furthermore, a different timing of
cumulus-corona cell removal has no effect on the outcome of ICSI,
suggesting that the surrounding cells are not necessary for survival,
fertilization and cleavage after ICSI.
相似文献
32.
In a second update of a systematic review, many new developments in the
combined drug treatment of rheumatoid arthritis (RA) are highlighted. In
early RA patients, step-down bridge therapy that includes corticosteroids
leads to much enhanced efficacy at acceptable or low toxicity. The effects
on joint damage may be persistent, but the symptomatic effects are probably
dependent on continued corticosteroid dosing. In late patients, cyclosporin
improves a suboptimal clinical response to methotrexate, and the triple
combination of methotrexate, sulphasalazine and hydroxychloroquine appears
to be clinically better than the components. Other combinations are either
untested, tested at low sample size, or show negative interaction. In view
of the low volume of evidence, most studies need confirmation by
replication.
相似文献
33.
34.
Ana Dorcas de Melo Inagaki Cristina Gardonyi Carvalheiro Rosana Cipolotti Ricardo Queiroz Gurgel Dayse Alves Rocha Kariny Souza Pinheiro Raquel Melo Araújo Dorothy Ribeiro Resende Lima Jacques Leon Winandy Marisa Márcia Mussi‐Pinhata 《Tropical medicine & international health : TM & IH》2012,17(11):1349-1355
Objectives To estimate, by neonatal screening, the birth prevalence of congenital toxoplasmosis among live‐born infants in Sergipe state, Brazil, and to investigate the clinical features of affected infants. Methods Dried blood spot specimens obtained from 15 204 neonates were assayed for the presence of anti‐T. gondii IgM antibodies. Duplicate retesting was done in infants with positive and borderline results. Confirmatory testing in peripheral blood samples consisted of testing for anti‐T. gondii IgG and IgM in infants and mothers. Those with possible congenital toxoplasmosis were evaluated and followed up to a median age of 20 months. Congenital infection was confirmed in the presence of persisting anti‐T. gondii IgG antibodies beyond 12 months of age. All infants with confirmed infection were treated with pyrimethamine, sulfadiazine and folinic acid for 1 year. Results Fifty‐three infants had detectable IgM in dried blood spot specimens. Confirmatory testing was reactive in 39/50, of which, 38 completed follow‐up. Six of 15 204 newborns were diagnosed with congenital toxoplasmosis, resulting in an estimated birth prevalence of four per 10 000 [CI 95% 1.4–8.0]. Four infants (67%) showed signs of congenital toxoplasmosis in their first year of life; three (75%) had retinochoroidal scars, and one had cerebral calcifications. Two infants remained asymptomatic until 20 months of age. Conclusions The birth prevalence of congenital toxoplasmosis is high in the Brazilian state of Sergipe, with most of the infants showing ocular lesions. Preventive measures are strongly warranted. 相似文献
35.
Debora M. Miranda Bernardo L. Wajchenberg† Maria R. Calsolari‡ Marcos J. Aguiar José M. C. L. Silva§ Marcia G. Ribeiro¶ Cristina Fonseca¶ Daniela Amaral¶ Wolfanga L. Boson Bruna A. Resende Luiz De Marco 《Clinical endocrinology》2009,71(4):512-517
Context Congenital generalized lipodystrophy, or Berardinelli–Seip syndrome, is a rare autosomal recessive disease caused by mutations in either the BSCL2 or AGPAT2 genes. This syndrome is characterized by an almost complete loss of adipose tissue usually diagnosed at birth or early infancy resulting in apparent muscle hypertrophy. Common clinical features are acanthosis nigricans, hepatomegaly with or without splenomegaly and high stature. Acromegaloid features, cardiomyopathy and mental retardation can also be present.
Design We investigated 11 kindreds from different geographical areas of Brazil (northeast and southeast). All coding regions as well as flanking intronic regions of both genes were examined. Polymerase chain reaction (PCR) amplifications were performed using primers described previously and PCR products were sequenced directly.
Results Four AGPAT2 and two BSCL2 families harboured the same set of mutations. BSCL2 gene mutations were found in the homozygous form in four kindreds (c.412C>T c.464T>C, c.518–519insA, IVS5-2A>G), and in two kindreds compound mutations were found (c.1363C>T, c.424A>G). In the other four families, one mutation of the AGPAT2 gene was found (IVS3-1G>C and c.299G>A).
Conclusions We have demonstrated four novel mutations of the BSCL2 and AGPAT2 genes responsible for Berardinelli–Seip syndrome and Brunzell syndrome (AGPAT2-related syndrome). 相似文献
Design We investigated 11 kindreds from different geographical areas of Brazil (northeast and southeast). All coding regions as well as flanking intronic regions of both genes were examined. Polymerase chain reaction (PCR) amplifications were performed using primers described previously and PCR products were sequenced directly.
Results Four AGPAT2 and two BSCL2 families harboured the same set of mutations. BSCL2 gene mutations were found in the homozygous form in four kindreds (c.412C>T c.464T>C, c.518–519insA, IVS5-2A>G), and in two kindreds compound mutations were found (c.1363C>T, c.424A>G). In the other four families, one mutation of the AGPAT2 gene was found (IVS3-1G>C and c.299G>A).
Conclusions We have demonstrated four novel mutations of the BSCL2 and AGPAT2 genes responsible for Berardinelli–Seip syndrome and Brunzell syndrome (AGPAT2-related syndrome). 相似文献
36.
Monika Oláhová Tobias B Haack Charlotte L Alston Jessica AC Houghton Langping He Andrew AM Morris Garry K Brown Robert McFarland Zofia MA Chrzanowska-Lightowlers Robert N Lightowlers Holger Prokisch Robert W Taylor 《European journal of human genetics : EJHG》2015,23(7):935-939
Isolated mitochondrial complex IV (cytochrome c oxidase) deficiency is an important cause of mitochondrial disease in children and adults. It is genetically heterogeneous, given that both mtDNA-encoded and nuclear-encoded gene products contribute to structural components and assembly factors. Pathogenic variants within these proteins are associated with clinical variability ranging from isolated organ involvement to multisystem disease presentations. Defects in more than 10 complex IV assembly factors have been described including a recent Lebanese founder mutation in PET100 in patients presenting with Leigh syndrome. We report the clinical and molecular investigation of a patient with a fatal, neonatal-onset isolated complex IV deficiency associated with multiorgan involvement born to consanguineous, first-cousin British Asian parents. Exome sequencing revealed a homozygous truncating variant (c.142C>T, p.(Gln48*)) in the PET100 gene that results in a complete loss of enzyme activity and assembly of the holocomplex. Our report confirms PET100 mutation as an important cause of isolated complex IV deficiency outside of the Lebanese population, extending the phenotypic spectrum associated with abnormalities within this gene. 相似文献
37.
Primary tumor cells of myeloma patients induce interleukin-6 secretion in long-term bone marrow cultures 总被引:6,自引:9,他引:6
Lokhorst HM; Lamme T; de Smet M; Klein S; de Weger RA; van Oers R; Bloem AC 《Blood》1994,84(7):2269-2277
Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM. 相似文献
38.
Fabianna Resende De Jesus-Moraleida Paulo Henrique Ferreira Manuela Loureiro Ferreira Juscelio Pereira Da Silva Marcella Guimarães Assis Leani Souza Máximo Pereira 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(1):55-63
Objective
Low back pain (LBP) is little explored in the aging population especially when considering age-relevant and culturally dependent outcomes. We aimed to describe socio-demographic and clinical characteristics of Brazilian older people with a new episode of LBP presenting to primary care.Methods
We sourced baseline information on socio-demographic, pain-related and clinical characteristics from 602 older adults from the Brazilian Back Complaints in the Elders (Brazilian BACE) study. We analyzed differences in pain, disability, functional capacity and psychosocial factors between sub-groups based on age (i.e. participants aged 55–74 or ≥75 years), education (i.e. those with four years or less of schooling or those with more than four years of schooling) and income (i.e. participants who reported earning two or less minimal wages or three and more).Results
Participants presented severe LBP (7.18/10, SD: 2.59). Younger participants were slightly more disabled (mean difference 1.29 points, 95% confidence interval [CI]: 0.03/5.56), reporting poorer physical health, and less fall-related self-efficacy (mean difference of 2.41, 95% CI 0.35/4.46). Those less educated, and those with income equal or less than two minimum wages had more disability, pain catastrophizing and worse functional capacity.Conclusions
This was the first study showing that Brazilian older adults with LBP present high levels of functional disability and psychological distress, especially those with low socioeconomic status. 相似文献39.
Ferraz Ana Paula Seara Fernando A. C. Baptista Emanuelle F. Barenco Thais S. Sottani Thais B. B. Souza Natalia S. C. Domingos Ainá E. Barbosa Raiana A. Q. Takiya Christina M. Couto Marcos T. Resende Gabriel O. Campos de Carvalho Antonio C. Ponte Cristiano G. Nascimento Jose Hamilton M. 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2021,35(4):719-732
Cardiovascular Drugs and Therapy - In the present study, the therapeutic efficacy of a selective BKCa channel opener (compound X) in the treatment of monocrotaline (MCT)-induced pulmonary arterial... 相似文献
40.
Pereira Silva JA Costa Dias F Fonseca JE Canhao H Resende C Viana Queiroz M 《Clinical rheumatology》2004,23(1):19-20
Scuba diving is associated with a 90% reduction in effective weight and with the loss of a weight-bearing effect on joints. These conditions are very similar to the continuous weightlessness that occurs in spaceflight and bed-rest, which are clearly associated with significant bone mass loss. Here, we studied the bone mineral density (BMD) of 66 professional scuba divers using a dual-photon densitometer, and have depicted a reduction in the BMD in comparison to a matched control group of non-divers. Our results suggest that diving is also an activity where the unloading effect alters bone metabolism, leading to a reduction in BMD.Abbreviations BMD
Bone mineral density 相似文献