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111.
Amanda?J?DaleyEmail author Robert?J?Copeland Neil?P?Wright Jerry?KH?Wales 《BMC public health》2005,5(1):113
Background
While obesity is known to have many physiological consequences, the psychopathology of this condition has not featured prominently in the literature. Cross-sectional studies have indicated that obese children have increased odds of experiencing poor quality of life and mental health. However, very limited trial evidence has examined the efficacy of exercise therapy for enhancing mental health outcomes in obese children, and the Sheffield Obesity Trial (SHOT) will provide evidence of the efficacy of supervised exercise therapy in obese young people aged 11–16 years versus usual care and an attention-control intervention. 相似文献112.
While inhaled polycyclic aromatic hydrocarbons have long been suspected to
induce lung cancer in humans, their dosimetry has not been fully
elucidated. A key question is whether the critical exposure occurs during
absorption in the lungs, or if toxicants in the systemic circulation
contribute significantly to lung cancer risk. In particular, data are
needed to determine how the physical properties of inhalants affect local
dosimetry in the respiratory tract. Pyrene, a tobacco smoke component, was
selected for study because it has physical properties between those of
highly lipophilic benzo[a]pyrene and water- soluble nitrosamines. Aliquots
of 5 ng of pyrene dissolved in a phospholipid/ saline suspension were
instilled as a single-spray bolus in the posterior trachea of the dog just
anterior to the carina. For 3 h after instillation, blood was repeatedly
sampled from the azygous vein, which drains the mucosa around the point of
instillation, and from both sides of the systemic circulation. At 3 h
post-instillation, tissue samples were taken. Autoradiography was used to
determine the depth distribution of pyrene in the tracheal mucosa. The
concentration of pyrene-equivalent radioactivity in the azygous vein peaked
9 min after the instillation. At approximately 30 min after instillation, a
rapid early clearance phase shifted into a distinctly slower second
clearance phase. Rates of rapid clearance were, however, sufficiently slow
to indicate diffusion-limited absorption of pyrene in the trachea. This
finding was corroborated by high concentrations of pyrene in the epithelium
as determined by autoradiography. High epithelial concentration of pyrene
combined with a slow penetration into the circulating blood allowed
substantial first-pass metabolic conversion of pyrene in the tracheal
mucosa. A total of 13% of the instilled pyrene was retained in the tracheal
mucosa 3.2 h after instillation; of this, 29% was parent compound, 52% was
organic-extractable metabolites, 14% was water-soluble metabolites and 6%
(approximately 1% of the instilled amount) was covalently bound to tracheal
tissues. Results support the inference that lipophilic protoxicants,
because of slow, diffusion-limited absorption, are more likely than
water-soluble protoxicants to be bioactivated in the lining epithelium and,
in turn, induce first-pass toxicity at the site of entry. In addition,
limitations were identified in the use of systemically distributed
biomarkers of PAHs, such as urinary hydroxypyrene levels, as indicators of
the biologically effective dose in airway target cells.
相似文献
113.
114.
Peritoneal interleukin-10 increases with decrease in activated CD4+ T lymphocytes in women with endometriosis 总被引:6,自引:5,他引:6
Ho HN; Wu MY; Chao KH; Chen CD; Chen SU; Yang YS 《Human reproduction (Oxford, England)》1997,12(11):2528-2533
This study was performed to determine whether peritoneal T cells are
suppressed in the CD4+ or CD8+ T cell subpopulation and whether they are
Th1 or Th2 predominant in women with endometriosis. Immune cells in the
peritoneal fluid (PF) were obtained from women undergoing laparoscopy for
endometriosis or tubal ligation. Three-colour flow cytometry was utilized
for immunophenotyping of peritoneal fluid mononuclear cells (PFMC).
Concentrations of interleukin (IL)-4, IL-5 and interferon-gamma (IFN-gamma)
produced by PFMC with and without mitogen stimulation and concentrations of
IL-10 and IL-12 were measured in PF. The peritoneal T lymphocytes were
predominantly of the Th1 type that produced much more IFN-gamma but less
IL-4 or IL-5 in women with or without endometriosis. The decrease in
peritoneal lymphocytes was significant in the HLA-DR+ CD4+ CD3+
subpopulation and the concentrations of peritoneal IL-10 and IL-12 were
significantly elevated in women with early stage endometriosis. There was
impaired IL- 5 production by PFMC after phytohaemagglutinin stimulation in
women with advanced stage endometriosis. We concluded that the activated
peritoneal CD4+ Th1 cells from the women with endometriosis were decreased
in number. The suppression of these T cells may be due to the elevation of
IL-10 and IL-12 in the peritoneal fluid.
相似文献
115.
Paired human chorionic gonadotrophin determinations for the prediction of pregnancy outcome in assisted reproduction 总被引:1,自引:0,他引:1
Chen CD; Ho HN; Wu MY; Chao KH; Chen SU; Yang YS 《Human reproduction (Oxford, England)》1997,12(11):2538-2541
The aim of this study was to determine the prognostic value of single and
paired measurements of serum concentrations of human chorionic
gonadotrophin (HCG) for successful pregnancy following in-vitro
fertilization (IVF) and tubal embryo transfer (TET). We analysed serum HCG
concentrations 15 and 22 days after IVF or TET in 198 conception cycles.
Cut-off values of serum HCG were determined by a receiver operating
characteristic (ROC) curve. On the basis of single HCG samples on day 15
(HCG15) after transfer, using a cut-off value of HCG15 = 150 mIU/ml, the
sensitivity was 71% and the specificity was 77%. The positive predictive
value (HCG15 > or = 150 mIU/ml indicating a normal pregnancy) was 89%,
while the negative predictive rate (HCG15 < 150 mIU/ml indicating an
abnormal pregnancy) was 51%. Patients with HCG15 < 150 mIU/ml but
HCG22/HCG15 ratio > or = 15, still had a 90% chance of normal pregnancy.
However, in patients with HCG15 < 150 mIU/ml and an HCG22/HCG15 ratio
< 15, there was an 84% chance of an abnormal pregnancy. We conclude that
a single HCG15 determination combined with the ratio of HCG22 to HCG15 has
a higher diagnostic accuracy for prediction of pregnancy outcome than
either analysis alone.
相似文献
116.
Total antioxidant status and nitric oxide do not increase in peritoneal fluids from women with endometriosis 总被引:7,自引:3,他引:7
Ho HN; Wu MY; Chen SU; Chao KH; Chen CD; Yang YS 《Human reproduction (Oxford, England)》1997,12(12):2810-2815
To explore the role of nitric oxide (NO) and oxidative stress in the
pathogenesis of adhesion formation and in endometriosis-associated
infertility, we examined the peritoneal total antioxidant status (TAS) and
the concentrations of products of NO metabolism in women with endometriosis
(early stage, n = 12; advanced stage, n = 12) and in fertile women without
endometriosis (n = 10). Peritoneal CA 125 and oestrogen and progesterone
concentrations were also measured to examine their contributions to TAS and
the production of NO. We failed to demonstrate any significant difference
in TAS and in the products of NO metabolism in peritoneal fluids among
women with early and advanced stages of endometriosis compared with fertile
women without endometriosis during the early follicular phase. TAS and the
concentration of the products of NO metabolism were not related to
concentrations of CA 125, oestrogen or progesterone. The concentration of
CA 125 in serum, but not in peritoneal fluid, was positively correlated
with the severity of endometriosis. The volume of peritoneal fluid and the
progesterone concentration were significantly increased in the group with
advanced endometriosis. TAS and the concentration of the products of NO
metabolism did not increase in peritoneal fluids from women with
endometriosis during the early follicular phase. Their role in the
pathophysiology of endometriosis needs to be explored further.
相似文献
117.
118.
119.
120.
Reinhard Storbeck Matthias Rehahn Matthias Ballauff 《Macromolecular chemistry and physics.》1993,194(1):53-64
The synthesis of high-molecular-weight polyesters based on 1,4:3,6-dianhydro-D -sorbitol (DAS), 1,4:3,6-dianhydro-D -mannitol (DAM) and 1,4:3,6-dianhydro-L -iditol (DAI) is reported. The polymers were obtained by polycondensation in solution of the dianhydrohexitols with terephthaloyl dichloride and 2,5-diethoxyterephthaloyl dichloride. The side groups of the latter monomer lead to a marked improvement of the solubility of the resulting polyesters which can be characterized by NMR techniques and osmometry. It is shown that all polyesters exhibit an excellent stability against thermal decomposition. Materials deriving from the polycondensation with terephthalic acid have glass transitions above 200°C if the molecular weight is high enough. The wide-angle X-ray analysis shows that polyesters deriving from terephthalic acid and DAM as well as DAI are semicrystalline. All results demonstrate that these polyesters partly deriving from renewable carbon sources present promising high Tg materials with excellent thermal stability. 相似文献