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951.
A. Cano C. Fernandez M. Scapa D. Boixeda G. Plaza 《The American journal of gastroenterology》1984,79(4):280-282
Two patients with pelvic and right hypochondrial pain and with purulent vaginal exudate in which Neisseria gonorrhoeae was isolated, are presented. Laparoscopy was used in both cases. A diagnosis of perihepatitis was made by demonstrating the typical adhesions in "violin string" shape and by obtaining clinical improvement after breaking up those adhesions. Our conclusion is that laparoscopy is a useful diagnostic and therapeutic procedure in young women with pain in the right upper quadrant of the abdomen and with signs of lower genital infection. 相似文献
952.
953.
Elena Cano Rita Carmona Adrián Ruiz-Villalba Anabel Rojas You-Ying Chau Kay D. Wagner Nicole Wagner Nicholas D. Hastie Ramón Mu?oz-Chápuli José M. Pérez-Pomares 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(3):656-661
Recent reports suggest that mammalian embryonic coronary endothelium (CoE) originates from the sinus venosus and ventricular endocardium. However, the contribution of extracardiac cells to CoE is thought to be minor and nonsignificant for coronary formation. Using classic (Wt1Cre) and previously undescribed (G2-Gata4Cre) transgenic mouse models for the study of coronary vascular development, we show that extracardiac septum transversum/proepicardium (ST/PE)-derived endothelial cells are required for the formation of ventricular coronary arterio–venous vascular connections. Our results indicate that at least 20% of embryonic coronary arterial and capillary endothelial cells derive from the ST/PE compartment. Moreover, we show that conditional deletion of the ST/PE lineage-specific Wilms’ tumor suppressor gene (Wt1) in the ST/PE ofG2-Gata4Cre mice and in the endothelium of Tie2Cre mice disrupts embryonic coronary transmural patterning, leading to embryonic death. Taken together, our results demonstrate that ST/PE-derived endothelial cells contribute significantly to and are required for proper coronary vascular morphogenesis.The coronary vascular system, whose function is necessary to sustain late embryonic and postnatal cardiac function, is formed by a complex network of blood vessels, including arteries, arterioles, capillaries, venules, and veins (1). Recent reports indicate that various sources of endothelial cells contribute to the mammalian embryonic coronary system (2–4). However, the specific fate and function of these different endothelial cell pools during coronary vascular morphogenesis is the subject of intense controversy (5).Two endocardial populations have been reported to participate in the building of the embryonic coronary vascular system. The first derives from the sinus venosus endocardium, which sprouts to give rise to the nascent Apelin+ coronary vasculature (2). A careful analysis of this study suggests that the sinus venosus endocardium, which is able to vascularize subepicardial and myocardial heart layers, mainly provides a cellular scaffold for the development of coronary veins (CoV). Accordingly, a second source of coronary endothelium (CoE) has been identified in the ventricular endocardium (Nfatc1+ lineage), which contributes massively to coronary arterial (CoA) endothelium (3, 6).A third disputed source of CoE is the proepicardium (PE), a structure that comprises epicardial progenitor cells. The PE protrudes from the septum transversum (ST), a folding of the lateral mesoderm that initiates the separation of thoracic and abdominal cavities in mammals (7). Although in vivo cell tracing and in vitro culture of avian PE cells clearly shows that PE cells can differentiate into CoE (8, 9), data from studies in mammals claimed the contribution of PE to CoE is minor (10–12). The so-called “epicardial” Cre constructs used in these studies are based on the expression of genes such as Gata5, Tbx18, or Wilms’ tumor suppressor (Wt1) (13). Because the final fate of these cells, the extent of their contribution, and their specific role during coronary blood vessel morphogenesis remain unknown, we aimed at studying these complex aspects of coronary development.
Open in a separate windowQuantification of epicardial lineage-derived endothelial cells reported by different studies is shown. 相似文献
Table S1.
Reported epicardial lineage-derived CoE cellsTransgenic mouse model | CoE cells from the tagged cell lineages | Reference |
Gata5Cre | None | Merki et al., 2005 (10) |
Tbx18Cre | Low, not quantified | Cai et al., 2008 (11) |
Wt1GFPCre | Low, not quantified | Zhou et al., 2008 (12) |
Sema3DCre | 6.9% of Sema3DCre+ cells | Katz et al., 2012 (13) |
ScxCre | 49% of ScxCre+ cells | Katz et al., 2012 (13) |
Wt1IRESGFPCre | 49.3% of total ventricular CD31+ cells | This work |
G2-Gata4Cre | 25.1% of total ventricular CD31+ cells | This work |
954.
The deleterious effects of low-dose corticosteroids on bone density in patients with polymyalgia rheumatica 总被引:4,自引:1,他引:4
Pearce G; Ryan PF; Delmas PD; Tabensky DA; Seeman E 《Rheumatology (Oxford, England)》1998,37(3):292-299
The beneficial effects of corticosteroid therapy in the treatment of
rheumatic diseases may be offset by the occurrence of corticosteroid-
related osteoporosis. This problem may be overcome by using low-dose
corticosteroids; however, the dose of corticosteroids that is both
efficacious and skeletal sparing is uncertain. Therefore, the aim of this
study was to determine whether low-dose prednisolone treatment results in
bone loss and modifies bone turnover. Nineteen patients (12 female, seven
male) suffering from polymyalgia rheumatica received 10 mg or less daily,
given in reducing dosage, with a range of 2.5-10 mg and an average of
6.0+/-0.2 mg daily (+/-S.E.M.). Prior to the commencement of therapy and at
regular intervals during treatment, bone mineral density (BMD) using dual
X-ray absorptiometry and circulating biochemical and hormonal determinants
of bone turnover were measured. The patients were followed for 14.4+/-1.6
months (range 6-27). They were compared to 19 age-matched controls. Despite
a mean exposure dose of 6 mg/day and disease remission, BMD decreased in
the patients at the lumbar spine (2.6+/-0.8%, P < 0.01), femoral neck
(2.9+/-1.5%, P=0.06), Ward's triangle (5.5+/-2.9%, P=0.06) and the
trochanter (4.3+/-1.9%, P < 0.05). Total body bone mass decreased by
50+/-19 g in the first 6 months (P < 0.02), and by 39+/-30 g in the
remaining 8 months of follow- up [not significant (NS)]. In the first 6
months, BMD decreased at the lumbar spine (1.7+/-0.9%, P = 0.06). From 6
months to the end of follow- up, BMD decreased by 8.5+/-3.5% at Ward's
triangle (P < 0.05) and by 4.8+/-2.5% at the femoral neck (P=0.08). The
fall in BMD correlated with the cumulative prednisolone dose at
trabecular-rich regions (trunk r=-0.72, P < 0.001; ribs r=-0.53, P <
0.05). Bone resorption, assessed by urinary cross-laps, was 54.7% higher
than controls before treatment was started (P < 0.05) and decreased by
23.5+/-7.1% in the first month of treatment when the mean prednisolone dose
was 9.1 mg/day, range 5-10 (P < 0.0001). Serum osteocalcin was not
suppressed by disease before treatment, decreased by 27.4+/-5.1% during the
first month of treatment (P < 0.001), remained suppressed while the
daily dose of prednisolone was > 5 mg/day, but returned to baseline
below this dose. Serum parathyroid hormone was 19.3% lower in the patients
than controls at baseline (NS), and increased by 46.1% (P < 0.05) but
was no higher than controls at any time. Muscle strength increased by
20-60% (P < 0.05 to < 0.01). Prophylaxis should be considered in
patients receiving > or = 5 mg/day prednisolone daily as bone loss is 2-
to 3-fold expected rates. Earlier trabecular bone loss may predispose to
spine and rib fracture; later cortical bone loss may predispose to hip
fractures. Doses of prednisolone of < 5 mg daily may be skeletal
sparing, but may not be efficacious.
相似文献
955.
Cano NJ Pichard C Roth H Court-Fortuné I Cynober L Gérard-Boncompain M Cuvelier A Laaban JP Melchior JC Raphaël JC Pison CM;Clinical Research Group of the Société Francophone de Nutrition Entérale et Parentérale 《Chest》2004,126(2):540-546
STUDY OBJECTIVE: To determine the predictive factors of morbidity and mortality in patients with end-stage respiratory disease. DESIGN: Prospective, multicenter cohort study. SETTING: Thirteen outpatient chest clinics within the Association Nationale de Traitement à Domicile de l'Insuffisance Respiratoire. PARTICIPANTS: Stable adult patients with chronic respiratory failure receiving long-term oxygen therapy and/or home mechanical ventilation (n = 446; 182 women and 264 men; aged 68.5 +/- 12.1 years [+/- SD]); Respiratory diseases were COPD in 42.8%, restrictive disorders in 36.3%, mixed respiratory failure in 13.5%, and bronchiectasis in 7.4%. Recruitment was performed during the yearly examination. Patients with neuromuscular diseases and sleeping apnea were excluded. MEASUREMENTS AND RESULTS: Hospitalization days and survival were recorded during a follow-up of 14.3 +/- 5.6 months. Body mass index (BMI), serum albumin, and transthyretin levels were considered for their predictive value of outcome, together with demographic data, underlying respiratory disease, respiratory function, hemoglobin, C-reactive protein, smoking habits, oral corticosteroid use, and antibiotic treatment courses. Overall, 1.8 +/- 1.7 hospitalizations (cumulative stay, 17.6 +/- 27.1 days) were observed in 254 of 446 patients (57%). Independent predictors of hospitalization were oral corticosteroids, FEV(1), and plasma C-reactive protein. One-year and 2-year cumulative survivals were 93% and 69%, respectively. Plasma C-reactive protein, BMI, Pao(2) on room air, and oral corticosteroids independently predicted survival in multivariate analysis. CONCLUSION: Besides established prognosis factors such as FEV(1) and Pao(2), nutritional depletion as assessed by BMI and overall systemic inflammation as estimated by C-reactive protein appear as major determinants of hospitalization and death risks whatever the end-stage respiratory disease. BMI and C-reactive protein should be included in the monitoring of chronic respiratory failure. Oral corticosteroids as maintenance treatment in patients with end-stage respiratory disease are an independent risk factor of death, and should be avoided in most cases. 相似文献
956.
957.
We tested whether the in vivo infusion of recombinant, soluble CTLA4 fused with Ig heavy chains, as a surrogate ligand used to block CD28/CTLA4 T-cell costimulation, could prevent efficient T-cell activation and thereby reduce graft-versus-host disease (GVHD). Lethally irradiated B10.BR recipients of major histocompatibility complex disparate C57BL/6 donor grafts received intraperitoneal injections of human CTLA4-Ig (hCTLA4-Ig) or murine CTLA4-Ig (mCTLA4-Ig) in various doses and schedules beginning on day -1 or day 0 of bone marrow transplantation (BMT). In all five experiments, recipients of CTLA4-Ig had a significantly higher actuarial survival rate compared to mice injected with an irrelevant antibody control (L6) or saline alone. Survival rates in recipients of hL6 or PBS were 0% at 29 to 45 days post-BMT. In recipients of CTLA4-Ig, survival rates were as high as 63% mice surviving 3 months post-BMT. However, protection was somewhat variable and recipients of CTLA4-Ig were not GVHD-free by body weight, clinical appearance, and histopathologic examination. There were no significant differences in the survival rates in comparing injection dose, injection duration, or species of CTLA4-Ig (hCTLA4-Ig v mCTLA4- Ig). Splenic and peripheral blood flow cytometry studies of long-term hCTLA4-Ig-injected survivors showed a significant peripheral B-cell and CD4+ T-cell lymphopenia, consistent with GVHD. A kinetic study of splenic reconstitution was performed in mice that received hCTLA4-Ig and showed that mature splenic localized CD8+ T-cell repopulation was not significantly different in recipients of hCTLA4-Ig compared with hL6, despite the significant increase in actuarial survival rate in that experiment. These data suggest that the beneficial effect of hCTLA4-Ig on survival is not mediated by interfering with mature donor- derived T-cell repopulation post-BMT. Neither hCTLA4-Ig nor mCTLA4-Ig interfered with hematopoietic recovery post-BMT. We conclude that CTLA4- Ig (most likely in combination with other agents) may represent an important new modality for GVHD prevention. 相似文献
958.
Fay JW; Lazarus H; Herzig R; Saez R; Stevens DA; Collins RH Jr; Pineiro LA; Cooper BW; DiCesare J; Campion M 《Blood》1994,84(7):2151-2157
Preclinical studies of recombinant human interleukin-3 (rhIL-3) and granulocyte-macrophage colony-stimulating factor (rhGM-CSF) have shown enhancement of multilineage hematopoiesis when administered sequentially. This study was designed to evaluate the safety, tolerability, and biologic effects of sequential administration of rhIL- 3 and rhGM-CSF after marrow ablative cytotoxic therapy and autologous bone marrow transplantation (ABMT) for patients with malignant lymphoma. Thirty-seven patients (20 patients with non-Hodgkin's lymphoma and 17 patients with Hodgkin's disease) received one of four different treatment regimens before ABMT. Patients were entered in one of four study groups to receive rhIL-3 (2.5 or 5.0 micrograms/kg/day) administered by subcutaneous injection for either 5 or 10 days starting 4 hours after the marrow infusion. Twenty-four hours after the last dose of rhIL-3, rhGM-CSF (250 micrograms/m2/d as a 2-hour intravenous infusion) administration was initiated. rhGM-CSF was administered daily until the absolute neutrophil count (ANC) was > or = 1,500/microL for 3 consecutive days or until day 27 posttransplant. The most frequent adverse events in the trial included nausea, fever, diarrhea, mucositis, vomiting, rash, edema, chills, abdominal pain, and tachycardia. Three patients were removed from the study because of chest, skeletal, and abdominal pain felt to be probably related to study drug. Four patients died during the study period because of complications unrelated to either rhIL-3 or rhGM-CSF. The median time to recovery of neutrophils (ANC > or = 500/microL) and platelets (platelet count > or = 20,000/microL) was 14 and 15 days, respectively. There were fewer days of platelet transfusions than seen in historical control groups using rhGM-CSF, rhG-CSF, or rhIL-3 alone. In addition, there were fewer days of red blood cell transfusions compared with historical controls using no cytokines or rhGM-CSF. These data indicate that the sequential administration of rhIL-3 and rhGM-CSF after ABMT is safe and generally well-tolerated and results in rapid recovery of multilineage hematopoiesis. 相似文献
959.
Minamoto GY; Scheinberg DA; Dietz K; Gold JW; Chein N; Gee T; Reich LM; Hoffer J; Mayer K; Armstrong D 《Blood》1988,71(4):1147-1149
Eighteen human immunodeficiency virus (HIV)-seropositive patients were found among 211 previously treated adult patients with a variety of leukemias who had been multiply transfused before April 1985. Patients known to be homosexual or intravenous drug users were excluded from this study. The spouse of one HIV-seropositive patient became HIV infected and subsequently developed the acquired immune deficiency syndrome. Patients with leukemia who were multiply transfused before the availability of screening of blood products for HIV antibody should be counseled regarding their individual risks of HIV infection and the risk to sexual contacts. 相似文献
960.
Platelets contain mitogenic activities for MCF-7 human breast cancer cells when assayed under serum-free chemically defined conditions. Purification from outdated human platelets identified insulinlike growth factor I (IGF-I) as the most potent breast cancer cell mitogen in lysates (Karey KP, Sirbasku DA: see accompanying article, this issue). In this study the release and subcellular localization of IGF-I was investigated. Degranulation of platelets by thrombin treatment caused release of lysosomal enzymes (beta-glucuronidase and N-acetyl-D- glucosaminidase), alpha-granule proteins (beta-thromboglobulin and fibrinogen) as well as mitogenic activity for MCF-7 cells and IGF-I as measured by radioimmunoassay (RIA) and radioreceptor assay. Release of mitogenic activity and immunologically identified IGF-I was induced tenfold over controls by thrombin and was nearly complete as compared to platelets disrupted by repeated freezing and thawing. Disruption of platelets by nitrogen cavitation followed by separation of the organelles by sucrose density gradient sedimentation showed that IGF-I and mitogenic activity localized predominantly to fractions containing alpha-granules rather than soluble cellular components, lysosomes, or dense granules. The morphology of MCF-7 cells in serum-free medium supplemented with supernatants from thrombin-treated platelets also indicated the release of important cell-adhesion factors for human breast cancer cells. 相似文献