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831.
Birth from cryopreserved embryos following in-vitro maturation of oocytes and intracytoplasmic sperm injection 总被引:2,自引:9,他引:2
Edirisinghe WR; Junk SM; Matson PL; Yovich JL 《Human reproduction (Oxford, England)》1997,12(5):1056-1058
This case report describes the birth of a baby following the transfer of
cryopreserved embryos generated from intracytoplasmic sperm injection
(ICSI) carried out on the second day after oocyte pick-up of
in-vitro-matured metaphase I and germinal vesicle stage oocytes. The couple
had a history of three failed intrauterine insemination attempts and
reduced fertilization rates in two previous in-vitro fertilization (IVF)
cycles. In the IVF-ICSI treatment cycle, 6/11 mature oocytes became
fertilized following ICSI on the first day. However, the patient failed to
conceive following the transfer of three embryos. Five oocytes were
immature (two at metaphase I stage and three with a germinal vesicle) and
these were cultured overnight. All had extruded a polar body by the
following day and ICSI was therefore performed; four oocytes became
fertilized, and were cryopreserved at the pronulear stage in propanediol.
In the next treatment cycle, transfer of frozen embryos was planned. The
pronuclear zygotes were thawed and cultured for 24 h prior to the transfer
of two embryos in a cycle stimulated with low doses of follicle stimulating
hormone. This resulted in a pregnancy and the delivery of a healthy baby
boy. In-vitro maturation of metaphase I and germinal vesicle oocytes which
are routinely collected in IVF-ICSI cycles, followed by second day ICSI
fertilization, may provide a valuable source of embryos for infertile
couples.
相似文献
832.
Glycoform composition of serum gonadotrophins through the normal menstrual cycle and in the post-menopausal state 总被引:7,自引:2,他引:7
Anobile CJ; Talbot JA; McCann SJ; Padmanabhan V; Robertson WR 《Molecular human reproduction》1998,4(7):631-639
The heterogeneity of follicle stimulating hormone (FSH) and luteinizing
hormone (LH) was investigated in five women aged 29.4 +/- 3.2 years (mean
+/- SD) throughout their menstrual cycles and in five post- menopausal
women aged 53.8 +/- 5.6 years. Chromatofocusing (pH range 7- 4) revealed
menstrual cycle stage- and postmenopausal-related differences in the serum
gonadotrophin charge. There were differences in the proportion of FSH with
an isoelectric point (pl) > 4.3 across phases of the menstrual cycle (P
= 0.019): midcycle (MC) 50%; early to mid-follicular (EMF) 36%; late
follicular (LF) 37%, luteal (L) 29% and following the menopause (PM) 17%.
There was no significant difference in the proportion of LH with pl >
6.55 between midcycle (53%) and EMF, LF or L phases (36, 43 and 32%
respectively); although all were greater than that found in the menopause
(13%). Concanavalin A chromatography revealed less (P < 0.005) complex
FSH and LH glycoforms at midcycle (63 and 13%) than in the EMF, LF and L
phases (90 and 18; 90 and 20 and 93 and 24% respectively). Menopausal
gonadotrophins were least complex (FSH 34%, LH 4%). There was a direct
relationship between serum FSH and FSH pl/complexity, and less acidic FSH
was associated with reduced FSH complexity. Increased oestradiol was
associated with basic FSH isoforms during the menstrual cycle and reduced
follicular phase FSH complexity. We conclude that changes in gonadotrophin
glycoforms occur through the menstrual cycle which are related to changes
in the prevailing steroid environment. Following the menopause oestrogenic
loss resulted in acidic, relatively simple glycoforms.
相似文献
833.
OBJECTIVES: Endothelial dysfunction is established in aged individuals; however, the mechanism(s) are not fully elucidated. We have previously identified l-arginine transport as a potential rate-limiting factor in nitric oxide (NO) production in heart-failure patients, characterized with endothelial dysfunction. We therefore aimed to investigate whether the age-related decline in endothelial function is due to reduced transport of the NO precursor, L-arginine. METHODS: Thirty-seven healthy males aged between 19 and 69 were recruited. Throughout 40 min of intra-arterial (i.a.) infusion of [3H]L-arginine (100 nCi/min), venous blood samples were withdrawn for the determination of L-arginine clearance. Venous occlusion plethysmography was then used to record the forearm blood flow responses to i.a. infusions of acetylcholine (ACh; 9.25 and 37 microg/min) and sodium nitroprusside (SNP; 2 and 8 microg/min). RESULTS: While ACh-induced vasodilation decreased with age (37 microg/min; young 15.87 +/- 1.30, middle-aged 9.59 +/- 1.33, older 10.42 +/- 1.12 ml/min per 100 ml tissue; P = 0.001), there was no change in forearm [3H]L-arginine clearance (young 126.08 +/- 19.05, middle-aged 122.47 +/- 20.96, older 126.56 +/- 19.56 ml/min; NS). Further [3H]L-arginine uptake studies in isolated peripheral blood mononuclear cells supported our in vivo findings, demonstrating no difference in [3H]L-arginine transport across the age spectrum. CONCLUSIONS: The present study excludes the hypothesis of impaired L-arginine transport as a potential mechanism for the age-related decline in endothelial function. 相似文献
834.
Contact dermatitis, an inflammatory response of the skin to an irritant or an allergen, can affect hospital staff. Most clinicians are routinely exposed to irritants such as latex, detergents, and chemicals. Treatment with topical corticosteroids and avoidance of suspect irritants usually resolves the dermatitis. A case study is presented of a licensed practical nurse who developed persistent contact dermatitis. The dermatitis did not resolve with 15 months of traditional treatments. Only after 3 months of treatment with two investigational topical products, which are now available to the public, was the dermatitis resolved and complete healing achieved. This case study discusses the new products and traditional treatment products used and presents results of irritant specificity testing and a series of photographs documenting resolution and healing. 相似文献
835.
An endogenous suppressor of hairy-wing insulator separates regulatory domains in Drosophila
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Parnell TJ Viering MM Skjesol A Helou C Kuhn EJ Geyer PK 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(23):13436-13441
Insulators define independent domains of gene function throughout the genome. The Drosophila gypsy insulator was isolated from the gypsy retrotransposon as a region that contains a cluster of binding sites for the Suppressor of Hairy-wing [Su(Hw)] protein. To study the effects of the gypsy insulator on gene expression within a single genomic domain, targeted gene replacement was used to exchange the endogenous yellow gene, located at cytological location 1A, with a set of gypsy-modified yellow genes. Replaced yellow genes carried a gypsy insulator positioned between the yellow promoter and either the upstream or the downstream tissue-specific enhancers. Whereas the gypsy insulator blocked the function of the upstream enhancers at the endogenous location, the downstream enhancers were not blocked. Investigation of the 1A region revealed two clustered Su(Hw)-binding sites downstream of the yellow gene, named 1A-2, that bind Su(Hw) in vivo and possess enhancer blocking function. We propose that interaction between 1A-2 and the gypsy insulator permits activation of yellow expression by enhancers in the neighboring achaete-scute complex, causing an apparent absence of the block of the downstream yellow enhancers. Based on these data, we suggest that 1A-2 is an endogenous Su(Hw) insulator that separates regulatory domains within the Drosophila genome. 相似文献
836.
Rackoff WR; Orazi A; Robinson CA; Cooper RJ; Alter BP; Freedman MH; Harris RE; Williams DA 《Blood》1996,88(5):1588-1593
This report examines the effect of filgrastim (granulocyte colony- stimulating factor, [G-CSF] in 12 patients with neutropenia [absolute neutrophil count [ANC] < 1,000/mm3]) caused by Fanconi anemia (FA). Two of 14 patients who were evaluated for study entry were ineligible because of unsuspected cytogenetic abnormalities in their bone marrow (BM). G-CSF was started at 5 micrograms/kg/d. All patients had an increase in their ANC at week 8 (mean increase = 15,664/mm3). The median ANC during therapy was 5,030/mm3. Eight of 10 patients who completed 40 weeks on study maintained an ANC > 1,500/mm3 on G-CSF given every-otherday. Four patients had an increase in their platelet count by week 8 without transfusion (maximum increase = 23,000 to 45,000/mm3); however, platelet counts fell toward baseline levels as the G-CSF dose was reduced. BM CFU-MK were increased at week 8 in three of four evaluable patients. Four patients who did not receive red blood cell transfusions had an increase in their hemoglobin level of at least 2.0 g/dL. A fifth patient had a red blood cell transfusion in week 2 and then had a similar increase in hemoglobin level without subsequent transfusion. Eight of 10 patients who completed 40 weeks of treatment showed increases in the percentage of BM CD34+ cells measured by flow cytometry. The same proportion showed increases in peripheral blood CD34+ cells. Increased BM cellularity and myeloid hyperplasia were constant findings and were associated with increased expression of the proliferating cell nuclear antigen. Adverse experiences were mild fever (1 patient) and a new BM cytogenetic abnormality at week 40 (1 patient). This study shows that prolonged administration of G-CSF exerts a stimulatory effect on the BM of FA patients and may be used to maintain a clinically adequate ANC in these patients. G-CSF has beneficial effects on multiple hematopoietic lineages in some patients and may be a good candidate for use in combination cytokine protocols for FA patients with progressive aplastic anemia. G-CSF use results in an increase in circulating CD34+ cells, a finding with important implications for future gene transfer protocols. 相似文献
837.
Background
Ischemic heart disease is the leading cause of death in the United States and the world. Advanced age is the strongest risk factor for ischemic heart disease and the best independent predictor for poor outcomes after acute coronary syndrome (ACS). Elderly patients are at high risk for ACS, and numerous studies have shown that octogenarians in particular experience increased morbidity and mortality compared to younger patients.Case Report
We describe a case of an 83-year-old woman who presented to the emergency department with a chief complaint of sore throat and was found to have a non-ST elevation myocardial infarction (NSTEMI) and was treated successfully with primary coronary intervention (PCI).Why Should an Emergency Physician Be Aware of This?
Chest pain is a common presenting symptom for ACS, but elderly patients with MI are more likely to present with other chief complaints. Only 40% of patients in the National Registry of Myocardial Infarction database ≥ 85 years of age had chest pain on initial presentation. Recent studies comparing invasive therapy (PCI or coronary artery bypass graft) with optimal medical therapy for patients > 75 years of age diagnosed with NSTEMI have reported a reduced risk of death and major cardiac events with invasive therapy. Emergency physicians should have a high level of suspicion for ACS in octogenarians, even in those presenting without chest pain. Timely diagnosis and management can improve morbidity and mortality in these patients. 相似文献838.
Figures WR; Scearce LM; DeFeo P; Stewart G; Zhou F; Chen J; Daniel J; Colman RF; Colman RW 《Blood》1987,70(3):796-803
Previous reports have indicated that the nucleotide affinity analog 5'- p-fluorosulfonylbenzoyl adenosine (FSBA) at concentrations between 40 and 100 mumol/L and at times greater than 20 minutes covalently modifies a single protein component on the external platelet membrane surface and that adenosine diphosphate (ADP) protects against this reaction. That this protein is an ADP receptor linked to platelet activation is shown by FSBA inhibition of ADP-mediated platelet shape change, aggregation, and fibrinogen receptor exposure. In this report, further evidence for the interaction of FSBA with the ADP receptor on platelets is provided by the observation that FSBA at high concentrations (100 to 500 mumol/L) behaves as a weak agonist to produce platelet shape change within one minute as detected by spectroscopic assay and scanning electron microscopy with concomitant phosphorylation of the light chain of platelet myosin. The specificity of FSBA as an agonist is demonstrated by inhibition of FSBA-induced shape change by ATP and the covalent incorporation of SBA as well as the failure of 5'-fluorosulfonylbenozoyl guanosine (FSBG) to cause shape change. In contrast, incubation of platelets with low concentrations of [3H]-FSBA (40 mol/L) is not associated with stimulation of platelet shape change or myosin light chain phosphorylation. 相似文献
839.
Wang LM; Michieli P; Lie WR; Liu F; Lee CC; Minty A; Sun XJ; Levine A; White MF; Pierce JH 《Blood》1995,86(11):4218-4227
Interleukin-13 (IL-13) induced a potent mitogenic response in IL-3- dependent TF-1 cells and DNA synthesis to a lesser extent in MO7E and FDC-P1 cells. IL-13 stimulation of these lines, like IL-4 and insulin- like growth factor-1 (IGF-1), resulted in tyrosine phosphorylation of a 170-kD substrate. The tyrosine-phosphorylated 170-kD substrate strongly associated with the 85-kD subunit of phosphoinositol-3 (PI-3) kinase and with Grb-2. Anti-4PS serum readily detected the 170-kD substrate in lysates from both TF-1 and FDC-P1 cells stimulated with IL-13 or IL-4. These data provide evidence that IL-13 induces tyrosine phosphorylation of the 4PS substrate, providing an essential interface between the IL- 13 receptor and signaling molecules containing SH2 domains. IL-13 and IL-4 stimulation of murine L cell fibroblasts, which endogenously express the IL-4 receptor (IL-4R alpha) and lack expression of the IL-2 receptor gamma subunit (IL-2R gamma), resulted in tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1)/4PS. Enhanced tyrosine phosphorylation of IRS-1/4PS was observed in response to IL-4, but not IL-13 treatment of L cells transfected with the IL-2R gamma chain. These results indicate that IL-13 does not use the IL-2R gamma subunit in its receptor complex and that expression of IL-2R gamma enhances, but is not absolutely required for mediating IL-4-induced tyrosine phosphorylation of IRS-1/4PS. 相似文献
840.
Leukemia of non-T lineage natural killer cells 总被引:2,自引:0,他引:2
Sheridan W; Winton EF; Chan WC; Gordon DS; Vogler WR; Phillips C; Bongiovanni KF; Waldmann TA 《Blood》1988,72(5):1701-1707
An unusual case of an aggressive leukemia of natural killer (NK) cells occurred in a 65-year-old male. Clinical characteristics of this case included hepatosplenomegaly, ascites, marrow infiltrate with leukemic cells, and a WBC up to 82.8 X 10(9) before therapy. One year before his presentation he had been noted to have a WBC of 12.1 X 10(9) with 78% lymphocytes, and 6 months before had noted intermittent fever and weight loss. He and his brother had well documented hereditary cold urticaria. The patient was treated with a modification of ProMACE CYTABOM regimen and had prompt regression of the leukemia with associated acute tumor lysis. Renal, hepatic, and marrow failure predominated during a terminal course that ended 22 days after therapy was commenced, and at autopsy there was no evidence for leukemic cell infiltrate in the liver, spleen or marrow. The leukemic cells were large granular lymphocytes by light and electron microscopic criteria, and had the following immunophenotype: CD2+, DR+, Leu7+, NKH1+, CD11+, CD3-, CD5-, CD4-, CD8-, CD16-. The cells displayed high antibody- dependent cell-mediated cytotoxicity (ADCC) and NK activity, and had a high rate of spontaneous proliferation in vitro that was not augmented by phytohemagglutinin (PHA), concanavalin A (Con A), or pokeweed mitogen (PWM). Southern analysis of DNA from leukemic cells revealed normal germline arrangements for the beta and gamma chains of the T cell antigen receptor and immunoglobulin heavy chain genes. The majority of metaphases were clonally abnormal revealing consistent rearrangements involving extra material attached to the long arms of chromosomes 5 and 11. 相似文献