全文获取类型
收费全文 | 716篇 |
免费 | 70篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 21篇 |
妇产科学 | 18篇 |
基础医学 | 115篇 |
口腔科学 | 17篇 |
临床医学 | 75篇 |
内科学 | 162篇 |
皮肤病学 | 24篇 |
神经病学 | 64篇 |
特种医学 | 58篇 |
外科学 | 54篇 |
综合类 | 3篇 |
预防医学 | 61篇 |
眼科学 | 9篇 |
药学 | 64篇 |
中国医学 | 4篇 |
肿瘤学 | 29篇 |
出版年
2023年 | 8篇 |
2022年 | 8篇 |
2021年 | 20篇 |
2020年 | 22篇 |
2019年 | 34篇 |
2018年 | 42篇 |
2017年 | 34篇 |
2016年 | 40篇 |
2015年 | 26篇 |
2014年 | 56篇 |
2013年 | 78篇 |
2012年 | 53篇 |
2011年 | 41篇 |
2010年 | 38篇 |
2009年 | 24篇 |
2008年 | 28篇 |
2007年 | 20篇 |
2006年 | 23篇 |
2005年 | 16篇 |
2004年 | 11篇 |
2003年 | 14篇 |
2002年 | 11篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 7篇 |
1998年 | 10篇 |
1997年 | 6篇 |
1996年 | 5篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1986年 | 3篇 |
1985年 | 9篇 |
1984年 | 3篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1977年 | 2篇 |
1975年 | 4篇 |
1974年 | 2篇 |
1972年 | 3篇 |
1971年 | 2篇 |
1969年 | 3篇 |
1934年 | 2篇 |
1926年 | 2篇 |
1924年 | 3篇 |
排序方式: 共有786条查询结果,搜索用时 15 毫秒
1.
Roky R Chapotot F Benchekroun MT Benaji B Hakkou F Elkhalifi H Buguet A 《Journal of sleep research》2003,12(2):95-101
During the lunar month of Ramadan, Muslims abstain from eating, drinking and smoking from sunrise to sunset. We reported previously that Ramadan provokes a shortening in nocturnal total sleep time by 40 min, an increase in sleep latency, and a decrease in slow-wave sleep (SWS) and rapid eye movement (REM) sleep duration during Ramadan. During the same study, the effects of Ramadan intermittent fasting on daytime sleepiness were also investigated in eight healthy young male subjects using a quantitative waking electroencephalograph (EEG) analysis following the multiple sleep latency test (MSLT) procedure. This procedure was combined with subjective alertness and mood ratings and was conducted during four successive experimental sessions: (1) baseline (BL) 15 days before Ramadan, (2) beginning of Ramadan (R11) on the 11th day of Ramadan, (3) end of Ramadan (R25) on the 25th day of Ramadan, (4) recovery 2 weeks after Ramadan (AR). During each session, four 20-min nap opportunities (MSLTs) were given at 10:00, 12:00, 14:00 and 16:00 h and were preceded by rectal temperature readings. Nocturnal sleep was recorded before each daytime session. Subjective daytime alertness did not change in R25 but decreased in R11 at 12:00 h, and subjective mood decreased at 16:00 h, both in R11 and R25. During the MSLT, mean sleep latency decreased by an average of 2 min in R11 (especially at 10:00 and 16:00 h) and 6 min in R25 (especially at 10:00 and 12:00 h) compared with BL. There was an increase in the daily mean of waking EEG absolute power in the theta (5.5-8.5 Hz) frequency band. Significant correlations were found between sleep latency during the MSLT and the waking EEG absolute power of the fast alpha (10.5-12.5 Hz), sigma (11.5-15.5 Hz) and beta (12.5-30 Hz) frequency bands. Sleep latency was also related to rectal temperature. In conclusion, Ramadan diurnal fasting induced an increase in subjective and objective daytime sleepiness associated with changes in diurnal rectal temperature. 相似文献
2.
Ivancic J Gulija TK Forcic D Baricevic M Jug R Mesko-Prejac M Mazuran R 《Virus research》2005,109(1):95-105
Eleven mumps vaccine strains, all containing live attenuated virus, have been used throughout the world. Although L-Zagreb mumps vaccine has been licensed since 1972, only its partial nucleotide sequence was previously determined (accession numbers , and ). Therefore, we sequenced the entire genome of L-Zagreb vaccine strain (Institute of Immunology Inc., Zagreb, Croatia). In order to investigate the genetic stability of the vaccine, sequences of both L-Zagreb master seed and currently produced vaccine batch were determined and no difference between them was observed. A phylogenetic analysis based on SH gene sequence has shown that L-Zagreb strain does not belong to any of established mumps genotypes and that it is most similar to old, laboratory preserved European strains (1950s-1970s). L-Zagreb nucleotide and deduced protein sequences were compared with other mumps virus sequences obtained from the GenBank. Emphasis was put on functionally important protein regions and known antigenic epitopes. The extensive comparisons of nucleotide and deduced protein sequences between L-Zagreb vaccine strain and other previously determined mumps virus sequences have shown that while the functional regions of HN, V, and L proteins are well conserved among various mumps strains, there can be a substantial amino acid difference in antigenic epitopes of all proteins and in functional regions of F protein. No molecular pattern was identified that can be used as a distinction marker between virulent and attenuated strains. 相似文献
3.
Vladimíra Džugasová Margita Obernauerová Katarína Horváthová Mariana Vachová Martina Žáková Július Šubík 《Current genetics》1998,34(4):297-302
The PEL1/PGS1 gene of the yeast Saccharomyces cerevisiae is essential for the viability of rho
–/rho° mutants and the normal cardiolipin content of cells. The PEL1-GFP fusion gene has been found to complement the pel1/pgs1 mutation and its fluorescent protein was localized to mitochondria similarly to the β-galactosidase activity of a protein encoded by the PEL1-lacZ fusion gene. The expression of the PEL1-lacZ reporter gene was repressed in cells grown in the presence of inositol and choline, reduced in the ino2 and ino4 strains, but constitutive in the opi1 null-mutant strain. The results demonstrate that Pel1p, playing a vital role in cells impaired in the mitochondrial DNA,
is localized in the mitochondria and expressed in response to inositol and choline.
Received: 15 June / 15 July 1998 相似文献
4.
I. TREBICHAVSKÝ F. KOVÁŘŮ V. STOŽICKÝ P. ŠIMAN 《American journal of reproductive immunology (New York, N.Y. : 1989)》1984,5(4):161-163
ABSTRACT: Placentomata of sheep immunized with human serum albumin (HSA) were examined. Both HSA and immunoglobulins were found in the maternal part and maternofetal border of the placenta using FITC labelled antisera on paraffin sections. Radiolabelled HSA was also detected in the fetal blood. The ultrastructure of placentomata revealed immunopathological process. 相似文献
5.
Plasma testosterone and catecholamine responses to physical exercise of different intensities in men
D. JeŽová M. Vigaš P. Tatár R. Kvetňanský K. Nazar H. Kaciuba-UŚcilko S. Kozlowski 《European journal of applied physiology》1985,54(1):62-66
Summary Plasma testosterone, noradrenaline, and adrenaline concentrations during three bicycle ergometer tests of the same total work output (2160 J·kg–1) but different intensity and duration were measured in healthy male subjects. Tests A and B consisted of three consecutive exercise bouts, lasting 6 min each, of either increasing (1.5, 2.0, 2.5 W·kg–1) or constant (2.0, 2.0, 2.0 W·kg–1) work loads, respectively. In test C the subjects performed two exercise bouts each lasting 4.5 min, with work loads of 4.0 W·kg–1. All the exercise bouts were separated by 1-min periods of rest.Exercise B of constant low intensity resulted only in a small increase in plasma noradrenaline concentration. Exercise A of graded intensity caused an increase in both catecholamine levels, whereas, during the most intensive exercise C, significant elevations in plasma noradrenaline, adrenaline and testosterone concentrations occurred. A significant positive correlation was obtained between the mean value of plasma testosterone and that of adrenaline as well as noradrenaline during exercise.It is concluded that both plasma testosterone and catecholamine responses to physical effort depend more on work intensity than on work duration or total work output.This work was performed within the Scientific Exchange Programme between the Institute of Experimental Endocrinology, Slovak Academy of Sciences in Bratislava and Medical Research Centre, Polish Academy of Sciences, Warsaw/Project 10.4/ 相似文献
6.
7.
G. Gjurić M. Prišlin-Muškić B. Žurga E. Nikolić R. Čordašić M. Stanojević 《European journal of pediatrics》1993,152(7):599-600
We report three newborns with different manifestations ofUreaplasma urealyticum infection; a term newborn with acute neonatal pneumonia and two very low birth weight infants with bronchopulmonary dysplasia and osteomyelitis of the femur, respectively. The association ofU. urealyticum with acute and chronic respiratory disease in term and preterm newborns has recently been reported. Our two cases are similar to other case reports from the literature, but we were unable to find any previous reports of osteomyelitis due toU. urealyticum in the premature babies. Isolation ofU. urealyticum in pure culture from the blood was considered to be related to local infection in all three patients. All patients were cured by erythromycin. 相似文献
8.
O. Djurković-Djaković N. Milošević-Jovčić S. Žerjav D. Šibalić 《European journal of pediatrics》1992,151(1):42-43
Sera from 263 newborns and infants suspected of congenital toxoplasmosis were tested for the presence of rheumatoid factor (RF) by the latex agglutination test, of which 40 were also tested by the enzyme-linked immunosorbent assay (ELISA). RF was detected in only one serum sample (0.38%), suggesting that false-positive results of the IgM-indirect fluorescent antibody test and the IgM-ELISA due to RF is most unusual in infancy. 相似文献
9.
Two newborn infants with duodenal and jejunal atresia and agenesis of the dorsal mesentery represent our surgical experience with "apple peel" small bowel or "christmas tree" demormity. The first patient had the typical appearance of this condition. The postoperative course was complicated by hyperbilirubinemia, septicemia, and disseminated intravascular coagulation. The infant is in satisfactory condition 1.5 years after operation. The second patient had agenesis of the dorsal mesentery without spiraling of the bowel around its vascular stalk. The child died after 1 month, with complete absence of extrahepatic bile ducts as seen at a second laparotomy. Neither child had been subjected to gastrostomy. 相似文献
10.
Terezija M HrŽenjak Maja PopoviĆ Ljerka TiŠka-rudman 《Pathology oncology research : POR》1998,4(3):206-211
u-PA is secreted by the most malignant tumors. As a response to u-PA synthesis surrounding cells synthetize inhibitors of
plasminogen activators for tissue protection. Plasminogen activators were found also in earthworm tissue. From the tissue
homogenate of earthworm Eisenia foetida the glycolipoprotein mixture named G-90 was isolated. It contains two serine proteases
(P I, P II) with fibrinolytic and anticoagulative activities. The fibrinolytic activity of G-90, P I and P II was tested in
an in vitro euglobulinic test applied to fibrin clot from blood plasma of patients suffered from malignant tumors. G-90 and
above-mentioned proteases applied in this study showed euglobulinic time proportionally with the concentrations of added substances.
The influence of G-90 on the fibrinolysis rate does not depend only on its concentration, but depends too on histological
type of tissue (organ) where the malignant tumors are located. Enzyme P I and P II do not show this activity. 相似文献