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Background
Some studies have found that lower parity and higher or lower social class (depending on the study) are associated with increased risks of childhood acute lymphoblastic leukaemia (ALL). Such findings have led to suggestions that infection could play a role in the causation of this disease. An earlier New Zealand study found a protective effect of parental marriage on the risk of childhood ALL, and studies elsewhere have reported increased risks in relation to older parental ages. This study aimed to assess whether lower parity, lower social class, unmarried status and older parental ages increase the risk of childhood ALL (primarily). These variables were also assessed in relation to the risks of childhood acute non-lymphoblastic leukaemia, non-Hodgkin's lymphomas and Hodgkin's disease. 相似文献6.
To resolve the apparent conflict between a lubricating glycoprotein,
'lubricin', as the active ingredient in synovial fluid (SF) and surface-
active phospholipid (SAPL) present in SF (and adsorbed to articular
cartilage) as the boundary lubricant reducing friction to such low
physiological levels, lubricin was isolated from bovine SF following the
original procedure of Swann et al. (Arthritis Rheum 1981;24:22-30).
Analysis of the lipid extract by thin-layer chromatography and phosphorus
determination demonstrated a phospholipid component of 11.1 +/- 1.7% (N =
5) which corresponds very closely to the 9.2-13.0% of lubricin which had
hitherto remained unidentified and which has previously been shown to be
transferable to the articular surface to impart lubrication. These results
would appear to resolve any theoretical conflict in that lubricin is,
indeed, an active ingredient within SF. Yet, as a large water-soluble
molecule, it really functions as a carrier for the highly insoluble SAPL
which it deposits on the articular surface as the oligolamellar layer
visualized in previous studies. However, it is this deposited SAPL, rather
than lubricin, which actually lubricates.
相似文献
7.
Florio P Perrone S Luisi S Longini M Tanganelli D Petraglia F Buonocore G 《Pediatric research》2003,54(5):696-700
Activin-A is a growth factor involved in cell growth and differentiation, neuronal survival, early embryonic development and erythropoiesis. Hypoxemia is a specific trigger for increasing activin-A in fetal lamb circulation. We tested the hypothesis that fetal hypoxia induces activin-A secretion in preterm newborn infants. Fifty newborn infants with gestational ages ranging from 26 to 36 wk were enrolled in a prospective study performed at the Pediatrics, Obstetrics and Reproductive Medicine Department, University of Siena, Italy. Heparinized blood samples were obtained from the umbilical vein after cord clamping, immediately after delivery. Activin A, hypoxanthine (Hx), xanthine (Xa) plasma levels and absolute nucleated red blood cell (NRBC) count were measured. Activin-A levels (p < 0.0001) and NRBC (p < 0.0001) were significantly higher in hypoxic than in non hypoxic preterm newborns. Cord activin A levels were significantly related with Hx (taua=0.64, taub=0.64, p < 0.0001) and Xa (taua=0.56, taub=0.57, p < 0.0001) levels, NRBC ((taua=-0.45, taub=-0.46, p < 0.0001) count; pH (taua=-0.47, taub=-0.48, p < 0.0001) and base deficit (taua=-0.36, taub=0.-0.36, p = 0.0002). Preterm newborns with signs of perinatal hypoxia at birth have increased activin-A levels, suggesting that activin-A may reflect indirectly intrauterine hypoxia. 相似文献
8.
Gaglani MJ Piedra PA Herschler GB Griffith ME Kozinetz CA Riggs MW Fewlass C Halloran ME Longini IM Glezen WP 《Archives of pediatrics & adolescent medicine》2004,158(1):65-73
BACKGROUND: The efficacy of the intranasal, live-attenuated, trivalent cold-adapted influenza virus vaccine (CAIV-T) against influenza A(H3N2) and B infections in healthy persons is established, but its effectiveness against natural influenza A(H1N1) infection is unknown. OBJECTIVE: To assess the effectiveness of CAIV-T in healthy children during the 2000-2001 influenza A(H1N1) and B epidemic. DESIGN: Community-based, nonrandomized, open-label trial from August 1998 through April 2001. SETTING: Intervention and comparison communities in central Texas. PARTICIPANTS: Healthy children, aged 1.5 to 18 years, from the intervention communities received a single dose of CAIV-T at least 1 time or more in 1998, 1999, and/or 2000. MAIN OUTCOME MEASURES: The incidence of medically attended acute respiratory illnesses during the 2000-2001 influenza epidemic was compared in 3794 health plan CAIV-T recipients with age-eligible, health plan nonrecipients in the intervention communities for direct effectiveness (n = 9325), and with those in the 2 comparison communities for total effectiveness (n = 16,264). RESULTS: The 2281 CAIV-T recipients in 2000 had significant direct protection against medically attended acute respiratory illness of 18% to 20% during the biphasic influenza A(H1N1) and B epidemic, and 17% to 26% during influenza A(H1N1) predominance. The 931 recipients of CAIV-T in 1999 containing influenza A/Beijing/262/95(H1N1) and B/Beijing/184/93-like viruses had persistent heterovariant protection against the 2000-2001 influenza A/New Caledonia/20/99(H1N1) and B/Sichuan/379/99 variants. The 616 recipients of a single CAIV-T dose in 1999 only, including those younger than 5 years with no prior natural exposure to influenza A(H1N1) viruses, showed persistent protection. CONCLUSION: Healthy children who received CAIV-T in 2000 or 1999 were protected against new variants of influenza A(H1N1) and B in the 2000-2001 influenza epidemic. 相似文献
9.
EA van Straaten L Koster-Kamphuis IM Bovee-Oudenhoven R van der Meer P-Ph Forget 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(5):528-531
BACKGROUND: Nitric oxide (NO) production catalyzed by iNOS (inducible NO synthase) is thought to take place mainly in macrophages after activation by inflammatory mediators. NO is subsequently oxidized to nitrite and nitrate, which are excreted in urine. The concentration of inflammatory mediators in small bowel biopsy specimens from patients with coeliac disease is increased. The latter could induce increased NO production by stimulation of intestinal macrophage iNOS, resulting in high levels of urinary NO oxidation products, nitrite and nitrate (NOx). AIM: In the present study we evaluated the urinary NOx/creatinine ratios in children with active coeliac disease (n = 22), coeliac disease patients on a gluten-free diet (n = 9), healthy (n = 11) and sick control children (n = 18). METHODS: The Griess reagent method was used for measuring urinary NOx. RESULTS: Median NOx/creatinine ratios of active coeliac disease patients, coeliac disease patients on a gluten-free diet, healthy and sick control patients were 1.21, 0.19, 0.10 and 0.13 mmol/mmol, respectively. All active coeliac disease patients showed increased NOx/ creatinine ratios. Urinary NOx/creatinine ratios of the active coeliac disease patients were significantly higher than those of healthy controls (p < 0.0001), sick controls (p < 0.0001) and coeliac disease patients on a gluten-free diet (p < 0.0001). CONCLUSION: The urinary NOx/creatinine ratio is increased in patients with active coeliac disease and reverts to normal on a gluten-free diet. 相似文献
10.
Oocyte morphology predicts outcome of intracytoplasmic sperm injection 总被引:10,自引:14,他引:10
Serhal PF; Ranieri DM; Kinis A; Marchant S; Davies M; Khadum IM 《Human reproduction (Oxford, England)》1997,12(6):1267-1270
To examine the influence of cytoplasmic morphology on the success rate of
intracytoplasmic sperm injection (ICSI), the morphology of 837 metaphase II
oocytes was assessed after cumulus stripping. The main abnormalities
detected were excessive granularity, cytoplasmic inclusions such as
vacuoles, smooth endoplasmic reticulum clustering and refractile bodies.
Microinjection was performed in 538 oocytes with normal cytoplasm, 142 out
of 161 with excessive granularity and 112 out of 138 with cytoplasmic
inclusions. Very poor oocytes were not injected. No difference was found in
fertilization rate. The embryos achieved cleaved normally and a similar
number of good quality embryos among the three groups was noted. The
outcome of transfer of embryos derived solely from normal oocytes (group A:
72 patients, 183 embryos) was compared with those from oocytes with
cytoplasmic abnormalities (group B: 34 patients, 85 embryos). In group A,
17 clinical pregnancies (24% per patient, implantation rate 10%) were
established. In group B, only one clinical pregnancy (3% per patient,
implantation rate 1%) was established, from the transfer of embryos derived
from oocytes with homogeneous granularity of the cytoplasm. No pregnancy
resulted following the transfer of embryos from eggs with cytoplasmic
inclusions. The difference was statistically significant. The outcome of
ICSI is dependent on the quality of the oocytes retrieved. Normal
fertilization and early embryo development were achieved in oocytes with
abnormal cytoplasm morphology, but the resulting embryos failed to
demonstrate the same implantation potential as those derived from oocytes
with normal cytoplasm.
相似文献