全文获取类型
收费全文 | 1430篇 |
免费 | 57篇 |
国内免费 | 147篇 |
专业分类
儿科学 | 70篇 |
妇产科学 | 22篇 |
基础医学 | 87篇 |
口腔科学 | 18篇 |
临床医学 | 212篇 |
内科学 | 320篇 |
皮肤病学 | 46篇 |
神经病学 | 62篇 |
特种医学 | 308篇 |
外科学 | 65篇 |
综合类 | 25篇 |
预防医学 | 67篇 |
眼科学 | 13篇 |
药学 | 244篇 |
1篇 | |
肿瘤学 | 74篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 9篇 |
2020年 | 7篇 |
2019年 | 8篇 |
2018年 | 20篇 |
2017年 | 7篇 |
2016年 | 15篇 |
2015年 | 18篇 |
2014年 | 30篇 |
2013年 | 54篇 |
2012年 | 34篇 |
2011年 | 43篇 |
2010年 | 50篇 |
2009年 | 59篇 |
2008年 | 63篇 |
2007年 | 136篇 |
2006年 | 55篇 |
2005年 | 49篇 |
2004年 | 30篇 |
2003年 | 21篇 |
2002年 | 45篇 |
2001年 | 32篇 |
2000年 | 24篇 |
1999年 | 31篇 |
1998年 | 81篇 |
1997年 | 80篇 |
1996年 | 73篇 |
1995年 | 65篇 |
1994年 | 43篇 |
1993年 | 52篇 |
1992年 | 15篇 |
1991年 | 18篇 |
1990年 | 16篇 |
1989年 | 53篇 |
1988年 | 34篇 |
1987年 | 34篇 |
1986年 | 30篇 |
1985年 | 27篇 |
1984年 | 25篇 |
1983年 | 15篇 |
1982年 | 31篇 |
1981年 | 14篇 |
1980年 | 14篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1977年 | 16篇 |
1976年 | 28篇 |
1975年 | 13篇 |
1973年 | 1篇 |
排序方式: 共有1634条查询结果,搜索用时 15 毫秒
1.
In patients with Type 2 diabetes, the appropriate intensity of glucose control is determined by age, life expectancy, and the presence of concomitant disease. Geriatric patients are especially susceptible to hypoglycaemia and therefore particular care should be taken in this group characterized by polypharmacy, renal or hepatic dysfunction, cardiovascular multimorbidity and malnutrition. As hypoglycaemia is a significant cause of morbidity and mortality, treatment regimens for diabetes should minimize the occurrence of hypoglycaemic episodes and be tailored to the patient's individual needs. The pharmacological options for treating Type 2 diabetes have increased considerably and the risk of hypoglycaemia of the currently available drugs varies considerably. Metformin, thiazolidinediones, and acarbose, oral antidiabetic drugs that decrease insulin resistance or postprandial glucose absorption, are associated with a low risk of hypoglycaemia. These drugs can also be used effectively in various combination regimens; however, by improving insulin sensitivity, combinations of metformin and thiolidinediones with sulphonylureas or meglitinides may considerably increase the risk of hypoglycaemia. On account of its complex pharmacoprofile glibenclamide is a problematic substance carrying a high risk of hypoglycaemia. There are limited preliminary data indicating that, under routine conditions, glimepiride may be associated with a lower risk of hypoglycaemia than glibenclamide and is no more likely to cause hypoglycaemia than other shorter-acting agents such as gliclazide and glipizide. Nateglinide and repaglinide as short-acting insulin secretagogues may be associated with a reduced risk of hypoglycaemia compared with glibenclamide, in particular when dosed flexibly. Repaglinide might be beneficial in individuals with renal impairment. 相似文献
2.
3.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
4.
5.
6.
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities. 相似文献
7.
8.
EVIDENCE FOR MULTIPLE DISTINCT MAJOR HISTOCOMPATIBILITY COMPLEX CLASS I LINEAGES IN TELEOSTEAN FISH*
S. H. M. Van Erp E. Egberts R. J. M. Stet 《International journal of immunogenetics》1996,23(5):371-381
In the context of studies on the expression of MhcCyca-Z sequences of the common carp, PCR amplifications of exon 4 were performed on cDNA obtained from pooled thymi of 20 carp F1 individuals. Five recombinant clones (Cyca-TC3, -TC13, -TC15, -TC17 and -TC18) were found to be 96% similar to the exon 4 region of Cyca-ZA1. Each of the five sequences was unique, and differed in a few positions in both the nucleotide and the derived amino acid sequences from any of the Cyca-Z sequences known to date. These data suggest that multiple Z genes per locus are present in the carp, which are transcribed in the thymus. In the course of analysing the amplified Cyca-Z sequences, serendipity yielded a clone, Cyca-TC16, containing a class I-like sequence substantially different from any other carp class I sequence. The predicted amino acid sequence of Cyca-TC16 was most similar to the class I genes (Lach-U) from the coelacanth (42–46% amino acid identity). Cyca-TC16 contains three conserved β2-microglobulin contact residues, and the secondary structure was predicted by computer algorithms to be similar to that of the α3 domain of HLA-A2. Phylogenetic analysis shows that carp class I sequences reside in four distinct clusters: (i) Cyca-Z, Cyca-TC3, -TC13, -TC15, -TC17 and -TC18 together with Caau-Z from ginbuna crucian carp, (ii) Cyca-U with Bree-U (zebrafish) and Sasa-p30 (Atlantic salmon), (iii) Cyca-TC16 with Lach-U (coelacanth), and (iv) Cyca-C4. 相似文献
9.
P. M. L. A. van den Bemt A. C. G. Egberts A. W. Lenderink J. M. Verzijl K. A. Simons W. S. C. J. M. van der Pol H. G. M. Leufkens 《European journal of clinical pharmacology》1999,55(2):155-158
Objective: This study investigated the relative value of adverse drug events reported by doctors, nurses and patients.
Methods: The study was conducted on a total of four wards: the paediatric and internal medicine wards (including geriatric patients)
of two peripheral hospitals in the Netherlands. Adverse drug events were collected by spontaneous reporting (doctor and nurse
reports) and by daily ward visits, during which the patients were interviewed by a hospital pharmacist (patient reports).
Criteria for relative value of the reported adverse drug events were the number of potentially serious reactions, the number
of reactions not mentioned in the patient information leaflet and the number of reactions reported to new drugs (5 years or
less on the Dutch market). No formal causality assessment was applied.
Results: Over a period of 2 months in 1996 (Hospital I) and 2 months in 1997 (Hospital II) a total of 620 patients were included
in the study and adverse drug events were reported in 179 (29%) of these cases. Doctors reported a statistically significant
larger number of serious (26% of all doctor reports; odds ratio (OR) 3.2; confidence interval (CI) 1.2–8.7) and unknown (39%;
OR 2.5; CI 1.0–6.0) adverse drug events than patients themselves during the daily ward visit. Doctors also reported more serious
and unknown adverse drug events than nurses. Adverse reactions to new drugs were reported during the daily ward visit only
(8% of all daily ward visit reports).
Conclusion: This study reconfirms that doctors are the main source for reports of serious and unknown adverse drug events in hospitalized
patients. However, patients themselves seem to report more adverse reactions to new drugs (during the daily ward visit). By
focusing on patients using new drugs, the daily ward visit might become cost-effective. This needs to be explored in future
studies.
Received: 10 September 1998 / Accepted in revised form: 30 November 1998 相似文献
10.
Marrow regeneration after mechanical depletion 总被引:1,自引:0,他引:1
The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration. 相似文献