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Leg deformities were investigated in three flocks of broilers (n = 600, n = 817, n = 361). Two types of twisted legs were characterized: varus of the tarsal joint (1 to 3% of birds) and valgus of the tarsal joint (30 to 40% of birds) with mild, intermediate and severe valgus angulation. Varus angulation appeared suddenly, between 5 and 15 days of age, was unilateral in 80% of cases and affected mainly the right limb. Medial tendinous displacement was always present and led to severe locomotor handicap and, as a consequence, decreased 7-week body weights. In the right legs, a marked inward rotation of the femora, medial angulation of the tibiotarsi and metatarsi, and a shallow distal groove in the tibiotarsus were observed. By contrast, the load bearing limbs showed anteroposterior curvature of the tibiotarsus. Valgus angulation appeared progressively between 2 and 7 weeks of age and became severe in 5% of cases. This disorder was often bilateral. In 60% of birds affected with severe valgus, there was lateral displacement of the gastrocnemius tendon. Mild locomotor disturbance was observed in broilers with intermediate angulation, while severe valgus was associated with lameness, antero-posterior curvature of tibiotarsi and lateral deviations of metatarsi and in some birds a reduction in growth rate. Absence of other bone deformity in birds with mild and intermediate valgus suggests that valgus angulation does not originate from bone abnormalities. Clinical, epidemiological and anatomical differences between both types of angulations suggest that they may be of a different aetio-pathogenesis. Varus could originate from early displacement of the gastrocnemius tendon, which seemed secondary to leg deformation in birds affected with valgus angulation. 相似文献
4.
The Periotest® device was used to evaluate the damping characteristics of different bone‐to‐implant interfaces of Brånemark implants. Implant and abutment lengths were found to have a significant influence on Periotest value (PTV). There was no statistical difference between PTVs of implants located in the anterior and posterior areas of the same jaw at abutment connection. No differences were found between PTVs of standard and self‐tapping implants. PTVs at abutment connection were highly influenced by the bone quality. The contact with two corticals, one at each extremity of the implant, was of a greater influence in the maxillary than in the mandibular jaw, indicating a firmer anchorage between the bicortical implants and the surrounding bone. A proaressive decrease of PTVs over time was observed, significant up to 5 years of loading. 相似文献
5.
Terry?O?Herndon Salvador?Gonzalez TR?Gowrishankar R?Rox?Anderson James?C?WeaverEmail author 《BMC medicine》2004,2(1):12
Background
Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo. 相似文献6.
Study of the protective effects of hyperimmune immunoglobulins G and M against endotoxin in mice and rats 总被引:1,自引:0,他引:1
We prepared solutions of human IgM and IgG to various lipopolysaccharide (LPS) species. These were then tested, along with
solutions of non-LPS specific human IgG or IgM, for their ability to confer passive immunity against experimental endotoxemia
in two animal models. The immunoglobulins were first tested for an effect on the lethality induced by seven different LPSs
in actinomycin-D sensitized mice, or by three different bacteria in normal mice. When the immunoglobulins were administered
1 h before challenge, a small protective effect was observed. This protection was dependent upon both the anti-LPS agent,
the chemical composition of the LPS, or the strain of Gram-negative bacteria used for injection. The anti-LPS IgM and IgG
preparations reduced the mortality induced by Escherichia coli but not by Serratia marcescens or Klebsiella pneumoniae, indicating protection by strain-specific antibodies. When the antibodies were preincubated with LPS or bacteria for 30 min
before administration, almost complete protection was seen. The influence of these immunoglobulin preparations or of human
albumin (as a control) on the hypotensive and vascular-permeabilizing effects of LPS in rats was then studied. A dose-dependent
inhibitory effect was observed with IgG preparations and albumin. At 200 mg/kg, anti-LPS IgG reduced the effects of LPS, while
at 400 mg/kg, both anti-LPS and normal IgG preparations showed protection, as did human albumin used at the same dose. The
IgM-enriched preparation worsened the initial hypotensive phase after LPS, whereas the anti-LPS IgM significantly reduced
the second phase of the hypotension, but only at the largest dose of 400 mg/kg. In this second model using the rat, a clear
difference between the activity of IgG and IgM was thus observed. We conclude that pretreatment with human immunoglobulins
from large plasma pools modestly, but significantly, attenuated the effects of murine and rat Gram-negative sepsis, but that
protection was incomplete. Our results suggest that single regimen intervention strategies may not be sufficient to influence
the course of the disease.
Received: 12 December 1998 相似文献
7.
Hincke MT Gautron J Mann K Panhéleux M McKee MD Bain M Solomon SE Nys Y 《Connective tissue research》2003,44(Z1):16-19
The eggshell is a highly ordered structure resulting from the deposition of calcium carbonate and an organic matrix from the acellular uterine fluid. Characterization of the individual matrix components is necessary to determine their influence upon calcite crystal shape, size, and orientation during eggshell calcification. We have purified and sequenced a novel 32-kDa protein, ovocalyxin-32 (OCX-32), which is present at high levels in the uterine fluid during the terminal phase of eggshell formation, and is localized predominantly in the outer eggshell. Database searches identified expressed sequence tags (ESTs) whose alignment yielded the complete cDNA. OCX-32 protein possesses limited identity (32%) to two unrelated proteins: latexin, a carboxypeptidase inhibitor expressed in rat cerebral cortex and mast cells, and to a skin protein that is encoded by a retinoic acid receptor-responsive gene, TIG1. The timing of OCX-32 secretion into the uterine fluid suggests that it may play a role in the termination of mineral deposition. 相似文献
8.
Eighty four out of 2151 militancy trauma patients sustained severe maxillofacial injury from Jan 1990 to March 1993. The resuscitation, stabilisation and intensive care of these patients was based on management priorities of primary resuscitation, care of airway, management of haemodynamics, oxygenation and monitoring. Anaesthesia was administered in a situation when the airway was likely to be compromised and the patients were critically sick. Initial ventilation and oxygenation was the most difficult and could be achieved with satisfactory seal around the face mask by applying water-soaked guaze pieces around the mouth and nose to “fill-in” the defects. Tracheal intubation could be accomplished with intravenous sedation by an experienced anaesthesiologist. Dental occlusion and wiring necessiated the placement of nasotracheal tube for 48-72 hours after surgery.KEY WORDS: Trauma, Maxillofacial injury, Trauma anesthesia, Anaesthesia and critical care 相似文献
9.
OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants. 相似文献
10.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183