全文获取类型
收费全文 | 77148篇 |
免费 | 41272篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 1541篇 |
儿科学 | 4214篇 |
妇产科学 | 582篇 |
基础医学 | 15527篇 |
口腔科学 | 5037篇 |
临床医学 | 12319篇 |
内科学 | 23329篇 |
皮肤病学 | 7438篇 |
神经病学 | 13410篇 |
特种医学 | 2174篇 |
外科学 | 13750篇 |
综合类 | 17篇 |
一般理论 | 23篇 |
预防医学 | 4190篇 |
眼科学 | 1217篇 |
药学 | 5576篇 |
中国医学 | 1009篇 |
肿瘤学 | 7085篇 |
出版年
2023年 | 29篇 |
2022年 | 60篇 |
2021年 | 1290篇 |
2020年 | 5037篇 |
2019年 | 10831篇 |
2018年 | 10097篇 |
2017年 | 11456篇 |
2016年 | 12082篇 |
2015年 | 11938篇 |
2014年 | 11841篇 |
2013年 | 12303篇 |
2012年 | 4123篇 |
2011年 | 4044篇 |
2010年 | 8939篇 |
2009年 | 5271篇 |
2008年 | 2049篇 |
2007年 | 892篇 |
2006年 | 962篇 |
2005年 | 687篇 |
2004年 | 715篇 |
2003年 | 726篇 |
2002年 | 805篇 |
2001年 | 768篇 |
2000年 | 691篇 |
1999年 | 256篇 |
1998年 | 40篇 |
1997年 | 35篇 |
1996年 | 32篇 |
1995年 | 30篇 |
1994年 | 26篇 |
1993年 | 20篇 |
1992年 | 35篇 |
1991年 | 34篇 |
1990年 | 28篇 |
1989年 | 31篇 |
1988年 | 24篇 |
1987年 | 16篇 |
1986年 | 14篇 |
1985年 | 14篇 |
1984年 | 13篇 |
1982年 | 15篇 |
1981年 | 7篇 |
1980年 | 7篇 |
1979年 | 8篇 |
1978年 | 9篇 |
1976年 | 7篇 |
1975年 | 8篇 |
1974年 | 9篇 |
1972年 | 9篇 |
1963年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 87 毫秒
91.
Krister W. Fjermestad Rene Huster Christina Thunberg Simen Stokke Claus H. Gravholt Anne‐Kristin Solbakk 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(2):482-492
A few studies have examined neuropsychological functions, sleep, and mental health combined in Klinefelter syndrome (KS; 47,XXY). We investigated neuropsychological functions with standard tests, sleep with actigraphy, and self‐reported mental health in 30 men with KS (Mean age = 36.7 years) compared to 21 controls (Mean age = 36.8 years). Men with KS scored significantly lower on mental speed, attention span, working memory, inhibition, and set‐shifting tests, as well as overall IQ (mean effect size difference Cohen's d = 0.79). Men with KS had significantly longer night wakes, with no differences in other sleep variables (mean d = 0.34). Men with KS reported poorer mental health than controls (mean d = 1.16). Regression analyses showed neuropsychological functions explained variance in some sleep domains for men with KS but not for controls. Neuropsychological functions explained variance in some mental health domains for controls. For men with KS, however, verbal IQ was the only significant predictor of mental health. Altogether, men with KS display problems in neuropsychological functions and mental health but do not appear different from controls on most sleep parameters. Our findings indicate that relations between neuropsychological functions, sleep, and mental health differ between men with KS and controls. 相似文献
92.
93.
94.
E. Estefanía N. Gmez‐Lozano R. De Pablo M. E. Moreno C. Vilches 《International journal of immunogenetics》2003,30(1):11-12
We have isolated the complete coding region of HLA‐B*39 from a Spanish Caucasoid, using a new PCR primer for its 5′ untranslated region. The cDNA matched partial genomic sequences of B*3924, an allele whose distribution appears to be restricted to Mediterranean and Arabian Caucasoids. A single amino acid change exclusive to B*3924 (threonine‐98) distinguishes it from B*3903. 相似文献
95.
J.‐F. Hardy 《ISBT科学丛刊》2007,2(1):168-177
Coagulopathy associated with massive transfusion (MT) remains an important clinical problem. The author attempted to identify the causes of coagulopathy in massively transfused, adult and previously haemostatically competent patients and to differentiate between the elective surgical and the emergency settings. A MEDLINE search was conducted for articles published on ‘massive transfusion’, ‘transfusion’, ‘trauma’, ‘surgery’, ‘coagulopathy’ and ‘haemostatic defects’. A narrative format was adopted. Coagulopathy associated with MT is an intricate, multifactorial and multicellular event. In patients undergoing elective surgery, a decrease in fibrinogen concentration is observed initially while thrombocytopenia is a late occurrence. Critically low levels of coagulation factors were seldom reported when whole blood was in common use. With the use of packed red blood cells (PRBC), dilution or consumption of coagulation factors has become a significant issue requiring specific treatment with, primarily, fresh frozen plasma (FFP). In the emergency setting (e.g., trauma, ruptured abdominal aortic aneurysm), tissue trauma, shock, tissue anoxia and hypothermia contribute to the development of disseminated intravascular coagulation and microvascular bleeding. It has been shown that the proactive administration of platelets and FFP improves coagulation, decreases haemorrhage and improves survival in these massively bleeding patients. We can only speculate that in this specific context, the benefits of early and aggressive platelet and coagulation factor replacement are related to the ongoing consumption coagulopathy at the time of surgery. 相似文献
96.
Antibody against fusarochromanone (TDP‐1) was obtained from rabbits after immunization with TDP‐1 conjugated to bovine serum albumin (BSA). An indirect enzyme‐linked immunosorbent assay (ELISA) using TDP‐1‐ovalbumin conjugate as the antigen coated on to the microtiter plate was used for monitoring the antibody liter. For toxin detection, a direct competitive ELISA in which TDP‐1 was conjugated to horseradish peroxidase (HRP) was used. Competitive direct ELISA revealed that the antibody had about 5.6 and 4.5 times greater binding efficiency for monoacetyl fusarochromanone (TDP‐2) and diacetylated TDP‐1 than TDP‐1. The concentration causing 50% inhibition of binding of TDP‐1‐HRP to the antibody by TDP‐1, TDP‐2 and diacetyl‐TDP‐1 were 2.8, 0.5 and 0.62 ng/ml, respectively. For the analysis of fusarochromanones in wheat and barley, the toxins were first extracted from the commodities with 100% methanol. A small aliquot of the extract was dried, acetylated, diluted in buffer and then analyzed directly by ELISA. The overall recovery for fusarochromanone in the wheat and barley samples spiked with TDP‐1 in the concentration range of 20 to 500 ppb were found to be 97% and 103.4% with cv of 15% and 11.2% for barley and wheat, respectively. 相似文献
97.
L Horváth M Sasvári-Székely T Spasokukotskaja F Antoni M Staub 《Immunology letters》1989,22(2):161-166
Nine subpopulations of tonsillar lymphocytes and the unseparated cells were compared in their utilization of exogenous deoxycytidine ([5-3H]CdR) and thymidine ([3H]TdR). Uptake phosphorylation and incorporation of labeled precursors were determined in B and T lymphocytes, in low density (LD; enriched in S phase cells) and in high density (HD; enriched in G0/G1 phase cells) cell fractions as well as in LD and HD subfractions of B and T lymphocytes, and in cells isolated from follicles of tonsils. As expected, LD cells and B lymphocytes were more active in TdR incorporation than HD cells and T lymphocytes. However, the ratio of [5-3H]CdR to [3H]TdR in their total phosphorylation and incorporation into DNA was much lower than the expected value of 1: about 0.5 for total phosphorylation and about 0.3 for incorporation in all subpopulations, except for the follicular cells, where these ratios were 1.0 and 0.7, respectively. These results show that the relative utilization of the two pyrimidine deoxyribonucleoside precursors varies among different lymphocyte subpopulations. However, this variation is not due to the different rate of DNA synthesis; rather, it depends on the differentiation stage of lymphocytes occurring in the germinal center of the follicles. 相似文献
98.
P. Rauch I. Hochel I. Vodrážka Z. Rumlová J. Káš J.‐L. Guesdon 《Food and Agricultural Immunology》1989,1(1):65-70
To check the concentrations of hen egg lysozyme in foodstuffs, added as a bacteriostatic agent, immunoassays based on different labels have been developed. The following detection limits (defined as non‐specific binding increased by three standard deviations) were achieved using antibody labelled with either peroxidase 125 I or a biotin‐streptavidin system: 0–8; 0–75 and 0–13 ng/ml, respectively. Only the most sensitive lysozyme immunoassay was likely to be suitable for application to analysis of cheese because matrix interference effects mean that sample extracts need to be diluted prior to assay. 相似文献
99.
100.
Emil Ginsburg Tatjana kari‐Juri Eugene Kobyliansky Ida Malkin Pavao Rudan 《American journal of human biology》2001,13(3):398-408
It was recently reported that the inheritance of the metacarpal cortical index (CI) in the Chuvashian population can be described in terms of a major gene (MG) model. By applying transmission probability tests, the hypothesis was accepted that not only baseline level of CI but also its sex‐specific dependence on age were under control of the same putative large‐effect gene. Using a pedigree sample from the population of the islands of Middle Dalmatia, Croatia (847 observed individuals in 278 pedigrees), data are presented to support the above findings. The following hypotheses were accepted: (i) inheritance of baseline CI in the Croatian population can be attributed to the effect of a MG responsible for about 42% of the variation; (ii) the same MG takes part in the control of the dependence of CI on age, particularly the age at onset of involutive bone changes (inflection point), and of the rate of decrease in CI with age (slope coefficient). Issues related to the assortative mating effect on CI and the determination of the most parsimonious model are discussed. Am. J. Hum. Biol. 13:398–408, 2001. © 2001 Wiley‐Liss, Inc. 相似文献