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991.
A wide variety of clinical and biochemical manifestations have been reported in association with pseudohypoparathyroidism and associated disorders. This is illustrated by a family study in which the affected members show widely differing characteristics. 相似文献
992.
Two patients are described with chronic hypoglycaemia; the first having glucose-6-phosphatase deficiency (type I glycogen storage disease), and the second fructose 1:6-diphosphatase deficiency. Both cases were associated with a bleeding diathesis, a defect of platelet aggregation, and a deficiency of platelet adenine nucleotides. The effect on the platelet abnormalities of a period of normoglycaemia was studied in both patients. Correction of the platelet abnormalities occurred rapidly after stabilization of the blood glucose within the normal range. Normal function persisted for the duration of the normoglycaemia, facilitating diagnostic liver biopsy and surgical procedures. A biochemical explanation for the nucleotide deficiency is suggested. 相似文献
993.
994.
Bijvoet AG; Kroos MA; Pieper FR; Van der Vliet M; De Boer HA; Van der Ploeg AT; Verbeet MP; Reuser AJ 《Human molecular genetics》1998,7(11):1815-1824
Glycogen storage disease type II (GSDII) is caused by lysosomal acid
alpha-glucosidase deficiency. Patients have a rapidly fatal or slowly
progressive impairment of muscle function. Enzyme replacement therapy is
under investigation. For large-scale, cost-effective production of
recombinant human acid alpha-glucosidase in the milk of transgenic animals,
we have fused the human acid alpha-glucosidase gene to 6.3 kb of the bovine
alphaS1-casein gene promoter and have tested the performance of this
transgene in mice. The highest production level reached was 2 mg/ml. The
major fraction of the purified recombinant enzyme has a molecular mass of
110 kDa and resembles the natural acid alpha-glucosidase precursor from
human urine and the recombinant precursor secreted by CHO cells, with
respect to pH optimum, Km, Vmax, N-terminal amino acid sequence and
glycosylation pattern. The therapeutic potential of the recombinant enzyme
produced in milk is demonstrated in vitro and in vivo. The precursor is
taken up in a mannose 6-phosphate receptor-dependent manner by cultured
fibroblasts, is converted to mature enzyme of 76 kDa and depletes the
glycogen deposit in fibroblasts of patients. When injected intravenously,
the milk enzyme corrects the acid alpha-glucosidase deficiency in heart and
skeletal muscle of GSDII knockout mice.
相似文献
995.
van der Vliet HJ Nishi N Koezuka Y von Blomberg BM van den Eertwegh AJ Porcelli SA Pinedo HM Scheper RJ Giaccone G 《Journal of immunological methods》2001,247(1-2):61-72
Natural killer T (NKT) cells have an extremely restricted T-cell receptor repertoire, in man consisting of a Valpha24 chain preferentially paired with a Vbeta11 chain, and play crucial roles in various immune responses. Characterization of circulating Valpha24(+)Vbeta11(+)-T cells is hampered by their low frequencies. The alpha-galactosylceramide KRN7000 was reported to be presented by CD1d to NKT cells. Since dendritic cells (DC) are potent antigen presenting cells, and have been shown to express CD1d, we analyzed whether these cells could efficiently mediate expansion of Valpha24(+)Vbeta11(+)-T cells. During a 7-day co-culture of peripheral blood mononuclear cells and KRN7000-loaded mature monocyte derived DC (moDC) in the presence of interleukin-7 (IL-7) and IL-15, we observed up to 76-fold expansion of Valpha24(+)Vbeta11(+)-T cells. The expanded Valpha24(+)Vbeta11(+)-T cells expressed the cytotoxic molecule granzyme B, showed negligible expression of Fas ligand and could be induced to express high levels of interferon-gamma, while retaining the capacity to produce IL-4. B cells, expressing CD1d, could also present KRN7000, but Valpha24(+)Vbeta11(+)-T cell expansion was only observed in the presence of IL-7 and/or IL-15. Considering the low frequency of circulating Valpha24(+)Vbeta11(+)-T cells, the present method for expansion of Valpha24(+)Vbeta11(+)-T cells using KRN7000-loaded mature moDC will be of value for the further characterization of this unique T cell subset. 相似文献
996.
Human tubal fluid: production, nutrient composition and response to adrenergic agents 总被引:1,自引:6,他引:1
Tay JI; Rutherford AJ; Killick SR; Maguiness SD; Partridge RJ; Leese HJ 《Human reproduction (Oxford, England)》1997,12(11):2451-2456
Vascularly perfused Fallopian tubes have been used to study the formation
and composition of human tubal fluid and the response to adrenergic agents.
An artery serving the tube was cannulated and perfused with Medium 199
supplemented with bovine serum albumin (BSA) and antibiotics. A second
cannula was attached to the fimbriated end for native tubal fluid
collection. The preparation was viable for up to 2 h. Tubal fluid was only
obtained in tubes removed in the proliferative and early secretory phases
of the ovarian cycle. Isoproterenol (1 mM) added to the perfusate
stimulated fluid production, whereas dibutyryl cyclic AMP (1 mM) reduced
fluid formation by 66%. Glucose, pyruvate and lactate concentrations in
tubal fluid, measured by microfluorescence assays, were 1.11, 0.14 and 5.4
mM respectively. The concentrations of 17 amino acids in tubal fluid were
measured by high performance liquid chromatography following fluorescence
derivatization. Arginine (0.19 mM) > alanine (0.11 mM) > glutamate
(0.09 mM) were present in highest concentration in all phases of the cycle.
All 17 amino acid concentrations in tubal fluid were below those in the
vascular perfusate. These data provides the basis for a culture medium
whose composition mimics the physiological environment to which early human
embryos are exposed.
相似文献
997.
Anderson RA; Wallace EM; Groome NP; Bellis AJ; Wu FC 《Human reproduction (Oxford, England)》1997,12(4):746-751
Inhibin has been postulated to be secreted by Sertoli cells in response to
follicle stimulating hormone (FSH) and in turn to exert an inhibitory
effect on FSH production. We have investigated this relationship using an
assay specific for dimeric inhibin B. A total of 56 normal men received 200
mg testosterone enanthate (TE) i.m. weekly, for 65 +/- 1 weeks in a trial
of hormonal male contraception. Before treatment a significant negative
correlation between inhibin B and FSH concentration (r = 0.49, P <
0.001) was observed. During TE treatment, luteinizing hormone (LH) and FSH
were rapidly suppressed. This was followed by a parallel decline in inhibin
B and sperm concentration. During the early recovery phase, inhibin B
concentrations remained suppressed in men who showed a delay in resumption
of spermatogenesis, despite higher FSH concentrations. Inhibin B returned
to pretreatment concentrations after 24 weeks recovery, when the inverse
relationship with FSH was restored. Our results showed the expected inverse
physiological relationship between inhibin B and FSH in normal men, with a
decline during TE treatment and alpha subsequent resumption of the inverse
relationship during recovery. These data clearly support the hypothesis
that inhibin B plays a physiological role in the feedback control of FSH
secretion, and reflects FSH-stimulated Sertoli cell function.
相似文献
998.
Inhibin A, inhibin B and activin A in the follicular fluid of regularly cycling women 总被引:4,自引:10,他引:4
Recent measurements of circulating inhibin A and inhibin B concentrations
indicate that inhibin B may play an important role in the selection of
dominant follicles. The concentrations of inhibin A, inhibin B and activin
A were measured in the follicular fluids of 61 individual follicles (4.8-20
mm in diameter) from 47 regularly cycling women using specific two-site
enzyme-linked immunosorbent assays. The microenvironment of each follicle
was characterized by measuring follicular fluid androstenedione and
oestradiol concentrations. The mean activin A concentrations were < 8
ng/ml for follicles of all sizes (4-17 mm). Inhibin A concentrations were
< 1 ng/ml in follicles < 6 mm, and progressively increased to
concentrations > 50 ng/ml in follicles > or = 13 mm. Follicles with
androstenedione/oestradiol ratios < or = 4 had higher concentrations of
inhibin A than follicles with androstenedione/oestradiol ratios > 4.
Inhibin B concentrations were higher than inhibin A concentrations in all
follicles, increasing from 19.2 +/- 8.3 ng/ml in 4 mm follicles to 409 +/-
9.6 ng/ml in 13 mm follicles and then declining to 275 +/- 47 ng/ml in 17
mm follicles. These results support the hypothesis that inhibin B may play
a more important paracrine role in developing follicles and a greater
regulatory role with respect to follicle stimulating hormone (FSH)
secretion than inhibin A.
相似文献
999.
Johnson KA Cunnington R Iansek R Bradshaw JL Georgiou N Chiu E 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,138(4):492-499
Movement-related potentials (MRPs) reflect increasing cortical activity related to the preparation and execution of voluntary
movement. Execution and preparatory components may be separated by comparing MRPs recorded from actual and imagined movement.
Imagined movement initiates preparatory processes, but not motor execution activity. MRPs are maximal over the supplementary
motor area (SMA), an area of the cortex involved in the planning and preparation of movement. The SMA receives input from
the basal ganglia, which are affected in Huntington's disease (HD), a hyperkinetic movement disorder. In order to further
elucidate the effects of the disorder upon the cortical activity relating to movement, MRPs were recorded from ten HD patients,
and ten age-matched controls, whilst they performed and imagined performing a sequential button-pressing task. HD patients
produced MRPs of significantly reduced size both for performed and imagined movement. The component relating to movement execution
was obtained by subtracting the MRP for imagined movement from the MRP for performed movement, and was found to be normal
in HD. The movement preparation component was found by subtracting the MRP found for a control condition of watching the visual
cues from the MRP for imagined movement. This preparation component in HD was reduced in early slope, peak amplitude, and
post-peak slope. This study therefore reported abnormal MRPs in HD, particularly in terms of the components relating to movement
preparation, and this finding may further explain the movement deficits reported in the disease.
Electronic Publication 相似文献
1000.
Boyton RJ; Lohmann T; Londei M; Kalbacher H; Halder T; Frater AJ; Douek DC; Leslie DG; Flavell RA; Altmann DM 《International immunology》1998,10(12):1765-1776
Glutamic acid decarboxylase (GAD65) has been implicated as a targeted self
antigen in the immune destruction of pancreatic beta cells. T cell
responses to GAD65 peptides have been detected in both patients with type I
diabetes and in the non-obese diabetic (NOD) mouse. To establish which
GAD65 epitopes are important in the immunopathogenesis of disease we
initially compared T cell responses to GAD65 epitopes in conditions of
disease susceptibility and protection. T cell responses to GAD65 peptides
were measured in monozygotic twin pairs selected on the basis of disease
discordance and T cell recognition of immunogenic regions of GAD65.
Peptides of interest were then used to immunize susceptible NOD mice and
H2-E transgenic NOD mice which are protected from diabetes. A differential
response to the epitope GAD65 521-535 discriminated diabetic from
non-diabetic human twins as well as susceptible from protected mice. This
epitope as well as GAD 505-519 induces T cell responses despite binding the
type I diabetes associated HLA- DQA1*0301/DQB1*0302 product with low
affinity. Since DQ-restricted T cell responses are difficult to study in
humans, HLA-DQ8 transgenic mice were then used: GAD epitopes 521-535 and
505-519 induced responses in DQ8 transgenic mice and T cell lines were
established. Long-term T cell lines against GAD 505-519 were HLA-DQ
restricted, and responded to peptide with a strong IFN-gamma and IL-10
response. The findings implicate GAD 521-535 as a possible target peptide
in pathogenesis and are compatible with a model whereby self-reactive T
cells specific for low-affinity peptide-MHC complexes may escape thymic
negative selection.
相似文献