全文获取类型
收费全文 | 821篇 |
免费 | 33篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 39篇 |
妇产科学 | 14篇 |
基础医学 | 72篇 |
口腔科学 | 18篇 |
临床医学 | 83篇 |
内科学 | 173篇 |
皮肤病学 | 10篇 |
神经病学 | 22篇 |
特种医学 | 248篇 |
外科学 | 41篇 |
综合类 | 16篇 |
预防医学 | 34篇 |
眼科学 | 8篇 |
药学 | 32篇 |
1篇 | |
中国医学 | 8篇 |
肿瘤学 | 25篇 |
出版年
2021年 | 5篇 |
2019年 | 3篇 |
2018年 | 4篇 |
2017年 | 4篇 |
2016年 | 4篇 |
2015年 | 10篇 |
2014年 | 7篇 |
2013年 | 15篇 |
2012年 | 9篇 |
2011年 | 25篇 |
2010年 | 29篇 |
2009年 | 23篇 |
2008年 | 15篇 |
2007年 | 20篇 |
2006年 | 20篇 |
2005年 | 14篇 |
2004年 | 6篇 |
2003年 | 10篇 |
2002年 | 10篇 |
2001年 | 10篇 |
2000年 | 10篇 |
1999年 | 11篇 |
1998年 | 40篇 |
1997年 | 34篇 |
1996年 | 35篇 |
1995年 | 47篇 |
1994年 | 38篇 |
1993年 | 38篇 |
1992年 | 12篇 |
1991年 | 4篇 |
1990年 | 11篇 |
1989年 | 37篇 |
1988年 | 24篇 |
1987年 | 30篇 |
1986年 | 40篇 |
1985年 | 21篇 |
1984年 | 18篇 |
1983年 | 15篇 |
1982年 | 15篇 |
1981年 | 19篇 |
1980年 | 18篇 |
1979年 | 10篇 |
1978年 | 16篇 |
1977年 | 15篇 |
1976年 | 14篇 |
1975年 | 13篇 |
1959年 | 2篇 |
1958年 | 4篇 |
1957年 | 6篇 |
1954年 | 2篇 |
排序方式: 共有857条查询结果,搜索用时 15 毫秒
81.
A five-drug remission induction regimen with intensive consolidation for adults with acute lymphoblastic leukemia: cancer and leukemia group B study 8811 总被引:23,自引:13,他引:23
Larson RA; Dodge RK; Burns CP; Lee EJ; Stone RM; Schulman P; Duggan D; Davey FR; Sobol RE; Frankel SR 《Blood》1995,85(8):2025-2037
The goal of this phase II multicenter clinical trial was to evaluate a new intensive chemotherapy program for adults with untreated acute lymphoblastic leukemia (ALL) and to examine prospectively the impact of clinical and biologic characteristics on the outcome. One hundred ninety-seven eligible and evaluable patients (16 to 80 years of age; median, 32 years of age) received cyclophosphamide, daunorubicin, vincristine, prednisone, and L-asparaginase; 167 patients (85%) achieved a complete remission (CR), 13 (7%) had refractory disease, and 17 (9%) died during induction. A higher CR rate was observed in younger patients (94% for those < 30 years old, 85% for those 30 to 59 years old, and 39% for those > or = 60 years old, P < .001) and in those who had a mediastinal mass (100%) or blasts with a T-cell immunophenotype. Eighty percent of B-lineage and 97% of T-cell ALL patients achieved a CR (P = .01). The coexpression of myeloid antigens did not affect the response rate or duration. Seventy percent of those with cytogenetic or molecular evidence of the Philadelphia (Ph) chromosome and 84% of those without such evidence achieved a CR (P = .11). Patients in remission received multiagent consolidation treatment, central nervous system prophylaxis, late intensification, and maintenance chemotherapy for a total of 24 months. After a median follow-up time of 43 months, the median survival for all 197 patients is 36 months; the median remission duration for the 167 CR patients is 29 months. Favorable pretreatment characteristics relative to remission duration or survival are younger age, the presence of a mediastinal mass or lymphadenopathy, a white blood cell count (WBC) less than 30,000/microL, L1 morphology, T or TMy immunophenotype, and the absence of the Ph chromosome. The estimates of the proportion surviving at 3 years are 69% for patients less than 30 years old, 39% for those 30 to 59 years old, 89% for those who had a mediastinal mass, 59% with WBC less than 30,000/microL, 63% with L1 morphology, 69% for T or TMy antigen expression, and 62% for those who lack the Ph chromosome. Fifteen patients (8%) had no unfavorable prognostic factors and have an estimated probability of survival at 5 years of 100% (95% confidence interval, 77% to 100%). This intensive chemotherapy regimen produces a high remission rate and a high proportion of durable remissions in adults with ALL. 相似文献
82.
The hematologic disorder paroxysmal nocturnal hemoglobinuria (PNH) occurs following an acquired somatic mutation in the Piga gene within a bone marrow stem cell. The progeny of this mutated cell cannot synthesize glycosylphosphatidylinositol (GPI) anchors, with a resultant deficiency in surface expression of all GPI-linked proteins. The protean clinical manifestations of PNH presumably result from the deficiency of these GPI-linked surface proteins. To explain the observation that neutrophils are affected at a significantly higher percentage than circulating erythrocytes and to analyze the proliferative rates of erythroid production in PNH, we studied 25 patients using flow cytometry. The fluorescent dye thiazole orange was used to detect reticulocytes, and CD59 monoclonal antibody was used to identify GPI-deficient cells. In contrast to the mature circulating erythrocytes, the percentage of abnormal reticulocytes was similar to the percentage of affected neutrophils. However, the vast majority of reticulocytes was completely GPI-deficient, ie, were type III cells, even in patients with only modest numbers of circulating type III erythrocytes. In addition, greater than 5% type II reticulocytes were identified in only 3 patients, although greater than 5% type II mature erythrocytes were identified in 10 of 25 patients. The results show that the erythroid and neutrophil bone marrow precursors have an equivalent proliferative advantage in PNH. The data also have important implications for the origin of type-II erythrocytes in PNH. 相似文献
83.
Elevated platelet count as a cause of abnormal von Willebrand factor multimer distribution in plasma 总被引:3,自引:1,他引:3
Twelve of 19 patients with myeloproliferative disorders showed a decrease of absence of the largest multimers of plasma von Willebrand factor (vWF) that correlated with elevated platelet counts but not with leukocyte counts. This suggested that platelets, rather than leukocytes, may be associated with the pathogenesis of the acquired vWF abnormality seen in these patients. To examine the hypothesis further, we studied 12 patients with reactive thrombocytosis after splenectomy. Increased platelet count (> 5 x 10(11)/L) after splenectomy was associated with vWF abnormalities indistinguishable from those detected in patients with myeloproliferative disorders. Accordingly, there was an inverse correlation between proportion of large vWF multimers and platelet, but not leukocyte, number: normalization of the platelet count was accompanied by restoration of a normal vWF multimeric pattern. These findings suggest that an increase in the number of platelets circulating in blood may favor the adsorption of larger vWF multimers onto the platelet membrane, resulting in their removal from the circulation and subsequent degradation. 相似文献
84.
2-Chloro-2'-deoxyadenosine (CldAdo) and 9-beta-D-arabinosyl-2- fluoroadenine (F-ara-A) have shown marked activity in the treatment of indolent lymphoid malignancies. Based on the susceptibility of various lymphocyte populations to apoptosis, we investigated whether CldAdo or F-ara-A would induce this process in lymphocytes from patients with chronic lymphocytic leukemia (CLL). In vitro exposure of leukemic lymphocytes to CldAdo or F-ara-A for 24 to 72 hours elicited features of apoptosis visible by light and electron microscopy. Analysis of DNA integrity showed DNA cleavage into nucleosomal-sized multimers. Using a quantitative assay, drug-induced DNA fragmentation was both time and dose dependent. Inhibition of active macromolecular synthesis did not prevent drug-induced fragmentation; however, both drug-induced and spontaneous DNA fragmentation were prevented by intracellular calcium chelation. In vitro culture with phorbol ester generally decreased drug- induced DNA cleavage. After prolonged incubation, CLL cells exhibited spontaneous cleavage; albeit, at significantly lower rates than drug- treated cells. Heterogeneity was observed for spontaneous and drug- induced DNA fragmentation and was significantly lower in B-leukemic cells obtained from patients with high-risk and refractory disease. We conclude that CldAdo and F-ara-A are potent inducers of apoptotic death in CLL and that this feature correlates with the disease status. 相似文献
85.
Single-locus DNA probes for tandem repeat sequences are now used in conjunction with particular endonucleases to characterize heritable restriction fragment lengths in parentage tests. Southern blots of this type, however, demonstrate only two attributes of an allele: its length and the presence of nucleotide sequences that are complementary to the probe. Not all restriction fragments of the same apparent length that react with the same probe are identical. Differences between comigrating fragments can be detected by the selection of a restriction enzyme that recognizes sites in a subset of the repeat sequences, and the information content of these loci is therefore increased. This report describes a paternity case in which two brothers appeared, after DNA phenotyping using Hinf I, to be the father. A second phenotyping using Hae III excluded one of the brothers. 相似文献
86.
87.
88.
FREDERIC TELLIEZ VERONIQUE BACH GERARD DEWASMES RE LEKE & JEAN-PIERRE LIBERT 《Journal of sleep research》1998,7(1):31-39
Sleep processes and body temperature regulation of neonates are never taken into account in the evaluation of nutrients, although these functions are implicated in the regulation of energy metabolism and are influenced by the nutritional state and its metabolic consequences. Medium-chain triglycerides (MCT) are currently used in paediatric units during the first weeks of because they are considered to be a rapid source of energy, easy to assimilate for growing premature infants, whose digestive function is immature. However, no study has described the thermic effect of these nutrients on body temperature regulation and sleep. The present study aimed at analysing the influence of three feeding formulas with different content of MCT on sleep processes and on thermoregulation of neonates fed until desired intake was reached. Whatever the thermal conditions (thermal equilibrium or cool environment), the MCT-fed groups had higher body temperatures and than groups fed without MCT, for whom total sleep time was reduced at thermal equilibrium. In this group, the large amount of quiet sleep seems to favour a strategy of conserving energy . Higher energy expenditure in MCT-fed groups is not harmful to growth rate since nutritional efficiency is even better reflected by a larger body mass gain. The thermic effect of MCT contributes to lessening the vulnerability of neonates exposed to low incubator temperatures. 相似文献
89.
90.
Efficacy study of the small-bowel examination 总被引:8,自引:0,他引:8