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991.
992.
B Torres-Álvarez JP Castanedo-Cazares C Fuentes-Ahumada B Moncada 《Journal of the European Academy of Dermatology and Venereology》2007,21(3):334-339
BACKGROUND: The mechanism of the action of methotrexate (MTX) in the treatment of psoriasis has not been completely elucidated. OBJECTIVE: To assess the effect of MTX on the expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, activation molecule CD69 and T-cell phenotype in skin specimens from patients with psoriasis. METHODS: We performed an immunohistochemical analysis of the expression of T-cell phenotype and cell adhesion/activation molecules in skin biopsies from patients with psoriasis treated with a fixed dose of MTX (12.5 mg/week). To determine data on the epidermal/dermal T-cell infiltration we carried out a manual quantification. RESULTS: Skin samples prior to therapy showed a moderate to severe inflammatory infiltrate, mainly due to T lymphocytes with a helper/inducer (CD4) phenotype. Most of these cells also expressed ICAM-1 and VCAM-1. Blood vessels showed expression of E-selectin and VCAM-1, and keratinocytes were positive for ICAM-1 staining. The cell infiltrate was reduced after therapy, as well as the expression of cell adhesion molecules. However, we also noted the persistence of the T lymphocyte phenotype CD8(+), expressing the CD69 activation molecule, after the MTX treatment. CONCLUSIONS: MTX downregulates the expression of some adhesion molecules, a phenomenon that may contribute to its anti-inflammatory therapeutic effect in psoriasis. The infiltrating T cells post-treatment have an activated cytotoxic phenotype, which may suggest a pathogenic role in the continuation and/or recurrence of psoriasis. 相似文献
993.
P. -E. Fournier R. Rizzoli D. -O. Slosman G. Theintz J. -P. Bonjour MD 《Osteoporosis international》1997,7(6):525-532
During puberty, the marked increases in both standing height and bone mass appear to be dissociated in time, the former occurring
earlier than the latter. However, the age or pubertal stage at which this dissociation is maximal in girls as opposed to boys,
and whether this dissociation is similar at all parts of the skeleton, are not clearly established. Standing height and bone
mineral mass, as assessed by measuring areal bone mineral density (BMD), at the levels of the lumbar spine, femoral neck and
midfemoral shaft, were measured in 98 females and 100 males between the ages of 9 and 19 years twice at a 1-year interval.
In males, the greatest difference between height and BMD gains occurred in the 13–14 year age group and was more pronounced
for the lumbar spine and femoral neck than for the midfemoral shaft. In females, the greatest difference was detectable at
a younger age (11–12 year age group) and appeared to be of a lower magnitude than in males. In both genders, the maximal difference
occurred during the period of peak height velocity, which corresponded to the pubertal stages P2-P3. Such a dissociation between
the rates of statural growth and mineral mass accrual could define a state of relatively low bone mass and contribute to the
higher incidence of fracture known to occur at the age and/or pubertal stage when this dissociation is maximal. 相似文献
994.
Atherosclerotic renal artery stenosis: ostial or truncal? 总被引:4,自引:0,他引:4
Kaatee R; Beek FJ; Verschuyl EJ; v.d. Ven PJ; Beutler JJ; van Schaik JP; Mali WP 《Radiology》1996,199(3):637
995.
Awareness and control of hypertension and hypercholesterolaemia in France and Northern Ireland 总被引:1,自引:0,他引:1
Marques-Vidal P; Evans AE; Cambou JP; Arveiler D; Luc G; Bingham A; Cambien F 《QJM : monthly journal of the Association of Physicians》1997,90(5):341-345
We assessed awareness and control of hypertension and hypercholesterolaemia
in a cross-sectional study of 586 men from France and 189 from Northern
Ireland, aged 35-55, without known coronary artery disease. Prevalence of
hypertension was 28% in France and 31% in Northern Ireland (p < 0.42).
In France, 70% of hypertensive subjects were aware of their status, vs. 58%
in Northern Ireland (p < 0.10). Overall, 40% of subjects with a history
of hypertension were untreated, and only 32% of the French and 12% of the
Northern Irish subjects treated for hypertension (diet with/without drugs)
were normotensive. The prevalence of hypercholesterolaemia was 46% in
France and 48% in Northern Ireland (p < 0.62). In France, 59% of
hypercholesterolaemic subjects were aware of their status, vs. only 17% in
Northern Ireland (p < 0.0001). In both countries, half of those with a
history of hypercholesterolaemia were untreated, and only 47% of the French
and 43% of the Northern Irish patients treated for hypercholesterolaemia
(diet with/without drugs) were controlled. While awareness of hypertension
is comparable in France and Northern Ireland, awareness of
hypercholesterolaemia is much lower in the latter. Control of hypertension
and hypercholesterolaemia in both countries is poor and should be improved.
相似文献
996.
Human gamete fusion can bypass beta1 integrin requirement 总被引:2,自引:2,他引:0
Since alpha6beta1 integrin has been shown to function as a sperm adhesion
receptor in the mouse, we investigated the potential role of beta1 integrin
in the gamete fusion process in humans. The expression of beta1 integrin
was morphologically analysed by indirect immunofluorescence and confocal
microscopy. A homogeneous and intense staining was detected at the plasma
membrane, and in some subcortical vesicles of germinal vesicle stage
oocytes (GV). Beta1 almost disappeared from oolemma and cytoplasm of
metaphase I (MI) oocytes, but was re-expressed as asymmetrical patches at
the plasma membrane of metaphase II stage oocytes (MII). A functional
fusion assay based on Hoechst or calcein-AM dye transfer from one gamete to
the other showed that maturing oocytes were able to fuse with an increasing
number of spermatozoa (11-22 from GV to MII respectively), and that fused
spermatozoa co-localized with beta1 integrin patches. Human gamete fusion
was only partially inhibited either by RGD-containing peptide (GRGDTP), or
by blocking anti-human beta1 integrin monoclonal antibody (DE9), with a
maximum of 50% inhibition. Despite the combined addition of GRGDTP and
blocking mouse anti-human beta1 integrin DE9 in the assay, a complete
inhibition of fusion could not be achieved. A mouse polyclonal antibody
raised against human oocyte membranes was more potent in inhibiting the
fusion. Since beta1 integrin expression at the plasma membrane was not
correlated to oocyte fusibility, and since it was only partially inhibited
by DE9 and/or RGD peptide, we suggest that human gamete fusion can bypass
the beta1 requirement. Beta1 integrin certainly participates in human
gamete fusion by acting in co-operation with multiple integrin/disintegrin
couples or another cofactor, not yet identified.
相似文献
997.
Methotrexate for the treatment of refractory Crohn's disease. 总被引:4,自引:2,他引:2
Lemann M Chamiot-Prieur C Mesnard B Halphen M Messing B Rambaud JC Gendre JP Colombel JF Modigliani R 《Alimentary pharmacology & therapeutics》1996,10(3):309-314
BACKGROUND: Previous studies suggested that methotrexate has beneficial effects in patients with Crohn's disease. We report our experience with this agent in patients with chronic active Crohn's disease who previously failed to improve with conventional treatment, including azathioprine in most cases. METHODS: Between June 1988 and June 1992, 39 patients with refractory Crohn's disease were treated with methotrexate. In patients with active disease, clinical remission was defined by a Harvey-Bradshaw index of less than 4. For patients also taking corticosteroids, the dates of remission and complete steroid withdrawal were recorded. For patients who achieved clinical remission, and those in clinical remission when methotrexate was started, the relapse rate on methotrexate therapy was noted. RESULTS: In the 37 patients with active disease at methotrexate initiation, the probability of remission was 72% at 3 months. The probability of remission and steroid withdrawal was 42% at 12 months. In patients on clinical remission, the probability of relapse on methotrexate was 58% at 12 months. Twenty-two patients experienced side-effects, but these only warranted methotrexate discontinuation in four cases. CONCLUSIONS: Methotrexate appears effective in most patients with refractory Crohn's disease and its short-term toxicity is acceptable, but the long-term benefit seems more limited. 相似文献
998.
Pardigon N; Bercovici N; Calbo S; Santos-Lima EC; Liblau R; Kourilsky P; Abastado JP 《International immunology》1998,10(5):619-630
The two-signal model states that activation of naive T cells requires a
signal 1 stimulus through the TCR and a co-stimulatory signal 2. By
contrast, signal 1 alone is sufficient for pre-activated T cells. Recently,
however, it has been shown that under certain conditions T cells can bypass
the requirement for co-stimulation. For example, CD28- deficient mice, when
immunized with lymphocytic choriomeningitis virus, mount a vigorous
cytotoxic T lymphocyte response and clear the virus. As a continuous effort
to unravel the mechanisms of T cell activation, we previously reported
activation of hybridoma T cells by recombinant single-chain MHC molecules
in the absence of antigen-presenting cells. In such reconstitution
experiments, since the signals delivered to the T cells are well
controlled, the contribution of any known or unknown signals can be ruled
out. In the present study, we analyzed the requirements for activation of
naive T cells by using splenocytes from TCR transgenic mice as a source of
responding cells. We observed that naive CD8+ T cells are fully activated
by signal 1 alone, but that co- stimulation lowers their activation
threshold. Previously activated T cells are fully responsive, even when the
first stimulation was performed in the absence of co-stimulation. They
display a low activation threshold and are insensitive to co-stimulation.
The physiological relevance of this finding and its consequences for
immunotherapy as well as for our understanding of self-tolerance are
discussed.
相似文献
999.
1000.
Spontaneous calcific cerebral embolus is a rare complication of calcific vascular disease such as calcified aortic plaques, and calcific aortic and mitral stenosis. Fewer than 10 case reports are described in the literature. Cerebral ischaemic symptoms may provide the indication for surgical replacement, even in the absence of valvular insufficiency or stenotic symptoms. We report a case of stroke in a young man with a known bicuspid calcific aortic valve. 相似文献