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排序方式: 共有435条查询结果,搜索用时 15 毫秒
101.
Son N Do Chinh Q Luong Dung T Pham Chi V Nguyen Tra T Ton Thao TN Pham Quoc TA Hoang Hanh T Hoang Dat T Nguyen Dai Q Khuong Quan H Nguyen Tuan A Nguyen Hanh TM Pham My H Nguyen Bryan F McNally Marcus EH Ong Anh D Nguyen 《Bulletin of the World Health Organization》2021,99(1):50
ObjectiveTo investigate factors associated with survival after out-of-hospital cardiac arrest in Viet Nam.MethodsWe did a multicentre prospective observational study of people (> 18 years) presenting with out-of-hospital cardiac arrest (not caused by trauma) to three tertiary hospitals in Viet Nam from February 2014 to December 2018. We collected data on characteristics, management and outcomes of patients with out-of-hospital cardiac arrest and compared these data by type of transportation to hospital and survival to hospital admission. We assessed factors associated with survival to admission to and discharge from hospital using logistic regression analysis.FindingsOf 590 eligible people with out-of-hospital cardiac arrest, 440 (74.6%) were male and the mean age was 56.1 years (standard deviation: 17.2). Only 24.2% (143/590) of these people survived to hospital admission and 14.1% (83/590) survived to hospital discharge. Most cardiac arrests (67.8%; 400/590) occurred at home, 79.4% (444/559) were witnessed by bystanders and 22.3% (124/555) were given cardiopulmonary resuscitation by a bystander. Only 8.6% (51/590) of the people were taken to hospital by the emergency medical services and 32.2% (49/152) received pre-hospital defibrillation. Pre-hospital defibrillation (odds ratio, OR: 3.90; 95% confidence interval, CI: 1.54–9.90) and return of spontaneous circulation in the emergency department (OR: 2.89; 95% CI: 1.03–8.12) were associated with survival to hospital admission. Hypothermia therapy during post-resuscitation care was associated with survival to discharge (OR: 5.44; 95% CI: 2.33–12.74).ConclusionImprovements are needed in the emergency medical services in Viet Nam such as increasing bystander cardiopulmonary resuscitation and public access defibrillation, and improving ambulance and post-resuscitation care. 相似文献
102.
KA Jackman AA Miller TM De Silva PJ Crack GR Drummond CG Sobey 《British journal of pharmacology》2009,156(4):680-688
Background and purpose:
Reactive oxygen species (ROS) derived from Nox2-containing reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity is reportedly detrimental in cerebrovascular disease. However, ROS generation by other Nox isoforms may have a physiological role. No Nox2-selective inhibitors have yet been identified, and thus it is unclear whether isoform non-selective Nox inhibitors would necessarily improve outcome after stroke. We assessed the effect of apocynin on cerebrovascular ROS production and also on outcome following cerebral ischaemia when administered either before ischaemia or after cerebral reperfusion. The involvement of Nox2-containing NADPH oxidase in the effects of apocynin was assessed using Nox2−/− mice.Experimental approach:
Transient cerebral ischaemia was induced by 0.5 h middle cerebral artery occlusion followed by 23.5 h reperfusion. Mice received apocynin (2.5 mg·kg−1, i.p.) either 0.5 h before ischaemia or 1 h after reperfusion. In situ superoxide production after cerebral ischaemia-reperfusion was measured in brain sections of wild-type mice at 24 h using dihydroethidium fluorescence.Key results:
Treatment with apocynin 0.5 h before ischaemia reduced total infarct volume, neurological impairment and mortality in wild-type but not Nox2−/− mice. Conversely, treatment with apocynin 1 h after initiation of reperfusion had no protective effect. Cerebral ischaemia and reperfusion increased superoxide production in the brain at 24 h, and pretreatment but not posttreatment with apocynin reduced superoxide levels.Conclusions and implications:
Apocynin improves outcome following stroke when administered before ischaemia in wild-type but not Nox2−/− mice. 相似文献103.
Raman Jay JE Heckman L Hinshaw S Best M Lubner DF Jarrard TM Downs SY Nakada FT Lee W Huang T Ziemlewicz 《Urologic oncology》2017,35(3):119
Purpose
Percutaneous biopsy obtained from a single location is prone to sampling error in large heterogeneous renal masses, leading to nondiagnostic results or failure to detect poor prognostic features. We evaluated the accuracy of percutaneous biopsy for large renal masses using a modified multi-quadrant technique vs. a standard biopsy technique.Materials and methods
Clinical and pathological data for all patients with cT2 or greater renal masses who underwent percutaneous biopsy from 2009 to 2014 were reviewed. The multi-quadrant technique was defined as multiple core biopsies from at least 4 separate solid enhancing areas in the tumor. The incidence of nondiagnostic findings, sarcomatoid features and procedural complications was recorded, and concordance between biopsy specimens and nephrectomy pathology was compared.Results
A total of 122 biopsies were performed for 117 tumors in 116 patients (46 using the standard biopsy technique and 76 using the multi-quadrant technique). Median tumor size was 10 cm (IQR: 8–12). Biopsy was nondiagnostic in 5 of 46 (10.9%) standard and 0 of 76 (0%) multi-quadrant biopsies (P = 0.007). Renal cell carcinoma was identified in 96 of 115 (82.0%) tumors and nonrenal cell carcinoma tumors were identified in 21 (18.0%). One complication occurred using the standard biopsy technique and no complications were reported using the multi-quadrant technique. Sarcomatoid features were present in 23 of 96 (23.9%) large renal cell carcinomas studied. Sensitivity for identifying sarcomatoid features was higher using the multi-quadrant technique compared to the standard biopsy technique at 13 of 15 (86.7%) vs. 2 of 8 (25.0%) (P = 0.0062).Conclusions
The multi-quadrant percutaneous biopsy technique increases the ability to identify aggressive pathological features in large renal tumors and decreases nondiagnostic biopsy rates. 相似文献104.
Roosmarijn TM van Hooijdonk Peter E Spronk Marcus J Schultz 《Critical care (London, England)》2014,18(2):1-2
Choice of the right renal replacement therapy for severe acute kidney injury in critically ill patients has been investigated many times in the last two decades. Although some questions have been answered, in current practice many different approaches are still used in the ICU. One basic and important issue is the frequency of renal replacement delivery: apart from pathophysiological speculations, in terms of hard outcomes (namely mortality and length of hospital stay) should dialysis be delivered continuously or intermittently? The authors of the CONVINT study provided a (last) response to this debate: in expert hands, the two treatments provide similar outcomes. This study confirms previous studies and is also important for other aspects, such as the possibility that the two modalities are complementary and may be indicated for different purposes. 相似文献
105.
P-glycoprotein expression in human plasma cell myeloma: correlation with prior chemotherapy 总被引:3,自引:3,他引:3
Grogan TM; Spier CM; Salmon SE; Matzner M; Rybski J; Weinstein RS; Scheper RJ; Dalton WS 《Blood》1993,81(2):490-495
Multidrug-resistant (MDR) myeloma patients failing chemotherapy may express P-glycoprotein (PGP), which serves as an efflux pump protecting the neoplastic cells. Unknown is whether PGP expression might relate to prior cytotoxic drug exposure. To address this question, we studied 106 consecutive bone marrow samples from 104 myeloma patients with samples studied either before or after therapy and at the time of relapse. We performed an established immunocytochemical assay of PGP using an MDR-1- specific monoclonal antibody and correlated PGP status with prior chemotherapy dosage. Myeloma patients with no prior therapy had a low incidence of PGP expression (6%, 3/47), whereas those receiving chemotherapy had a significantly higher incidence (43%, 21/49) (P < .0001). A substantially higher incidence of PGP expression (50%, 83%, respectively) occurred when the total vincristine dose exceeded 20 mg and when doxorubicin exceeded 340 mg. In the 11 patients who received both high vincristine and doxorubicin dosages (> 20 mg, > 340 mg total dose) there was 100% incidence of PGP expression in the tumor cells. These data provided the basis for a predictive mathematical model from which dose-related PGP expression normograms were generated. Time with myeloma for PGP-negative patients (mean 33 months) had overlapping confidence limits with PGP-positive patients (mean 42 months), suggesting that disease duration was not a significant variable. PGP expression did not correlate with other clinical factors or immunophenotypic factors. Our findings indicate a strong correlation between PGP expression in myeloma and past chemotherapy in myeloma, in particular, related to prior exposure to the natural product agents vincristine and doxorubicin. Additionally, the proportion of PGP- positive plasma cells was significantly higher in the doxorubicin- treated patients than the nondoxorubicin-treated patients (87.7% v 65.17%; P = .013). Combined high vincristine and doxorubicin total dosage appear highly predictive of PGP expression. 相似文献
106.
Absence of human T-cell lymphotropic virus type I coinfection in human immunodeficiency virus-infected hemophilic men 总被引:2,自引:0,他引:2
Concern for transmission of human T-cell lymphotropic virus, type 1 (HTLV-1) infection to recipients of infected cellular blood products has prompted development of tests to eliminate blood units with HTLV-I antibodies. Most hemophilic men from the United States became infected with human immunodeficiency virus (HIV) before HIV donor screening and before blood products were processed to inactivate the virus. To assess whether these men might also be infected with HTLV-I, we examined the HTLV-I antibody status of 127 factor VIII (hemophilia A) recipients and 71 factor IX (hemophilia B) recipients. One HIV-seronegative and four HIV-seropositive persons were HTLV-I reactive by enzyme-linked immunosorbent assay (ELISA). Four of five ELISA-reactive serum samples were negative by HTLV-I immunoblot assay (IB); 1 reactive and 1 borderline reactive serum were indeterminate on IB (p19 reactivity), but negative by radioimmunoprecipitation assay (RIPA). Peripheral blood mononuclear cells from one patient with indeterminate HTLV-I IB were negative for HTLV-I genomic sequences by polymerase chain reaction. The other indeterminate patient's serum antibody pattern was stable over a 2-year period, suggesting this was not an instance of early HTLV-I seroconversion. These results reaffirm the safety of factor components in the United States with regard to HTLV-I but emphasize the importance and need for further testing of reactive HTLV-I ELISA results with a second more specific technique. 相似文献
107.
Miller TP; Grogan TM; Dahlberg S; Spier CM; Braziel RM; Banks PM; Foucar K; Kjeldsberg CR; Levy N; Nathwani BN 《Blood》1994,83(6):1460-1466
The growth fraction of tumors from patients with non-Hodgkin's lymphomas (NHL) has been shown to correlate with survival in retrospective studies. The growth fraction can be evaluated using immunohistochemical techniques employing the Ki-67 monoclonal antibody (MoAb) that marks a nuclear protein present in cycling cells. The purpose of this study was to evaluate the clinical utility of the Ki-67 MoAb for predicting survival. Using a prospective trial design in a multi-institutional cooperative trials group, the proliferative index, clinical outcome, and statistical correlations were independently assessed for previously untreated patients with advanced stages of intermediate- and high-grade histologies of NHL treated on Southwest Oncology Group study (SWOG 8516, Intergroup 0067). The proportion of Ki- 67-positive cells was determined on snap-frozen thin tissue sections. A proliferative index of 80% or greater, as determined from prior retrospective studies, identified a group of patients (18%) who had a poor outcome. Overall survival was significantly reduced in these patients with a high Ki-67-associated proliferative index compared with those with a low proliferative index (P = .001). One-year survival estimates were 82% (low proliferative index) versus 18% (high proliferative index). A multivariate regression analysis incorporating commonly used clinical prognostic features confirmed the independent effect of proliferation on survival (relative risk estimate 5.9; 95% confidence interval, 2.2, 16.1). The Ki-67 MoAb identifies a group of patients with rapidly fatal NHL for whom currently available chemotherapy is inadequate. 相似文献
108.
Compartmentalization of cyclic GMP-dependent protein kinase in formyl- peptide stimulated neutrophils 总被引:2,自引:0,他引:2
The presence and physiologic role of cyclic GMP-dependent protein kinase (G-kinase) in human neutrophils was investigated by Western blot analysis and immunocytochemistry. Small quantities of G-kinase were found in the cytoskeletal-enriched fraction of neutrophil lysates as detected by Western blots using a polyclonal antibody raised against bovine aorta G-kinase. Immunofluorescence microscopy demonstrated in adherent neutrophils that G-kinase was localized diffusely within the cytoplasm, at the microtubule organizing center, and in the euchromatin of the nucleus. Because cyclic GMP is implicated as a modulator of neutrophil chemotaxis, G-kinase localization was investigated in neutrophils activated with N-formyl-methionyl-leucyl-phenylalanine (fMLP). fMLP stimulated transient focal changes in G-kinase localization that coincided with transient changes in cell shape. G- kinase translocated over a period of 5 minutes from diffuse staining of the cytosol to filaments within the uropod of polarized cells (1 minute), to bundles of filaments associated with loss of cell polarity (2.5 minutes), and finally to more intense staining of the nuclear euchromatin (5 minutes). Optical sectioning of neutrophils by confocal laser scanning microscopy confirmed that G-kinase was restricted to specific sub-cellular compartments during cell activation. This transient localization of G-kinase was disrupted by cytoskeletal inhibitors and was augmented by 8-Br-cyclic GMP. These data provide evidence for the first time that G-kinase plays a physiologic role in human neutrophils, and support the concept of compartmentalization of cyclic nucleotides during neutrophil activation. 相似文献
109.
Expression of v-src in a murine T-cell hybridoma results in constitutive T-cell receptor phosphorylation and interleukin 2 production. 总被引:5,自引:1,他引:5 下载免费PDF全文
J J O''Shea J D Ashwell T L Bailey S L Cross L E Samelson R D Klausner 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(5):1741-1745
Ligand binding to the T-cell antigen receptor results in phosphatidylinositol hydrolysis and the resultant activation of protein kinase C, as well as the activation of a receptor-coupled protein-tyrosine kinase. As a model for tyrosine kinase activation in T cells, we used retroviral gene transfer to express the v-src oncogene in an antigen-specific murine T-cell hybridoma. Clones that expressed v-src mRNA demonstrated constitutive tyrosine phosphorylation of several cellular substrates, including the zeta chain of the T-cell receptor, and constitutive interleukin 2 production. Thus, expression of a constitutively active protein-tyrosine kinase such as pp60v-src appears to be sufficient to induce the expression of at least one gene critical to the process of T-cell activation. 相似文献
110.
Hemoglobin A2 (HbA2; alpha 2 delta 2) is a powerful inhibitor of HbS (alpha 2 beta 2(3)) polymerization. However, HbA2 levels are normally low in sickle cell patients. We show that a major reason for low delta- globin gene expression is the defective CACCC box at -90 in the delta- globin promoter. When the CACCC box defect in delta is corrected, expression of an HS2 delta /Luciferase reporter is equivalent to HS2 beta /Luciferase. Erythroid Krupple-like factor (EKLF), which binds to the CACCC box of the beta-globin gene and activates high-level expression, does not bind to the normal delta-globin promoter. Our goal is to design a modified EKLF that binds to the defective delta-globin promoter and enhances delta-globin gene expression. To test the feasibility of this strategy, we inserted the beta-globin CACCC box at - 90 of the delta-globin gene promoter to produce an HS2 delta CAC-beta construct and quantitated human delta- and beta-globin mRNA in stably transformed murine erythroleukemia (MEL) cells. delta- Globin mRNA in these cells was 22.0% +/- 9.0% of total human globin mRNA (delta/delta + beta) as compared with 3.0% +/- 1.3% in the HS2 delta-beta control. In a second set of experiments a GAL4 DNA-binding site was inserted at - 90 of the delta-globin gene to produce an HS2 delta GAL4-beta construct. This construct and a GAL4(1-147)/EKLF expression vector were stably transfected into MEL cells. delta-Globin mRNA in these cells was 27.8% +/- 7.1% of total human globin mRNA as compared with 9.9% +/- 2.5% in the HS2 delta GAL4-beta plus GAL4(1-147) control. These results show that delta-globin gene expression can be significantly increased by a modified EKLF. Based on these results, we suggest that modified EKLFs, which contain zinc fingers designed to bind specifically to the defective delta-globin CACCC box, may be useful in gene therapy approaches to increase HbA2 levels and inhibit HbS polymerization. 相似文献