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41.
42.
The DSM-III and DSM-III-R criteria for "brief reactive psychosis" change the original concept of this disorder in a manner so restrictive as to virtually eliminate the diagnosis. In a companion paper to this one, we have reviewed the original concept and data supporting further study of this classification. We now argue that the operational criteria of the DSM-IIIs do not enhance the study of this putative disease entity, but rather thwart this goal by restricting the diagnosis so severely that too few cases will be found to test the third psychosis hypothesis. We suggest revised criteria that will retain the essential features of the traditional concept while defining explicit criteria in the style of the DSM-IIIs. 相似文献
43.
The variability in the concentration and biological availability of niacin in corn was investigated. Plots of both sweet and field corn were harvested at different stages. In rat growth assays for available niacin, grains harvested at the immature, "milky" stage and then dried gave values of 88 and 74 micrograms/g, respectively. These values were in contrast to the low growth assay values of 18 and 16 micrograms/g for grain harvested at maturity, and even higher than the value of approximately 56 micrograms/g obtained for each immature corn in both the Association of Official Analytical Chemists procedure of chemical analysis and a standard microbiological procedure. However, when the milky grains were precooked at neutral pH, the values from these procedures were higher and agreed with the biological assay results. It is suggested that, during the initial alkaline digestion used for these two procedures, a proportion of the niacin in NAD, the major form of niacin in milky corn, degrades. However, when the materials are first cooked at neutral pH, nicotinamide is released without loss, and the pyridine ring is then stable. The traditional American Indian practice of roasting and drying "green corn" apparently provided a valuable source of niacin. 相似文献
44.
K D Carpenter 《The Journal of nursing education》1989,28(6):256-264
Seventy-nine percent of academic middle managers for baccalaureate nursing reported that they did not plan to continue in their current management positions, or advance in academic leadership positions (George, 1981). This study examined the relationships between the job characteristics, a mediating variable "growth need strength", and the general job satisfaction and work motivation of academic middle managers for baccalaureate nursing. The sample was drawn from the population of academic middle managers for baccalaureate nursing in 126 colleges and universities across the United States that offer both baccalaureate and higher nursing degree programs. Sixty seven percent returned the Job Diagnostic Survey Short Form (JDSSF). The findings were interpreted through an examination of three analytical techniques: zero-order correlations, multiple regression, and multiple regression with interaction. Findings indicate that the dependent variable, "internal work motivation," can be measured in the population, but it cannot be predicted using the seven job characteristics measured by the JDSSF. The job characteristic autonomy was significant in predicting "general job satisfaction." General job satisfaction also proved to be some combination of security satisfaction and growth need satisfaction. both independent variables "autonomy" and "feedback from the job itself" were significant in predicting growth need satisfaction. As a mediating variable, "growth need strength" was not significant in predicting general job satisfaction in a linear model, nor was it significant when entered as an interactive term. However, the multiplicative model did increase, by four percent above the linear model, the amount of variance predictable in general job satisfaction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
45.
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47.
In-vitro maturation of human germinal vesicle stage oocytes: role of cumulus cells and epidermal growth factor in the culture medium 总被引:21,自引:6,他引:21
Goud PT; Goud AP; Qian C; Laverge H; Van der Elst J; De Sutter P; Dhont M 《Human reproduction (Oxford, England)》1998,13(6):1638-1644
In-vitro maturation (IVM) of oocytes is a promising technique to reduce the
costs and avert the side-effects of gonadotrophin stimulation for in-vitro
fertilization (IVF). The pregnancy rates from oocytes matured in vitro are
much lower than those of in-vivo stimulation cycles indicating that
optimization of IVM remains a challenge. Therefore, we investigated the
effect of supplementation of the medium with gonadotrophins, oestradiol and
epidermal growth factor (EGF) and the effect of retaining or removing the
cumulus cells on nuclear and cytoplasmic maturation of immature oocytes.
Human germinal vesicle (GV) oocytes obtained after gonadotrophin
stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a
complex defined medium either supplemented with gonadotrophins, oestradiol
and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and
oestradiol alone. The cumulus cells were either removed or kept intact. In
GV stage oocytes cultured without cumulus (group I) significantly more
oocytes reached the metaphase II (MII) stage at 30 h in media supplemented
with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with
intact cumulus (group II), more oocytes reached MII at 30 h than in group
I, but there was no difference in medium with or without EGF
supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of
MII oocytes was judged from their capability to activate and fertilize
after ICSI. In group I, the rates of activation and normal fertilization
were similar. However, in group II, significantly more oocytes underwent
normal fertilization in the EGF-supplemented than the unsupplemented group
(71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized
oocytes were similar in the sibling oocyte subgroups cultured with or
without EGF supplementation, but the overall cleavage rates were higher in
cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P
< 0.001). Thus, supplementation of the maturation medium with EGF and
maintenance of the cumulus during culture improve the nuclear and
cytoplasmic maturation of human oocytes in vitro.
相似文献
48.
Carpenter MG Thorstensson A Cresswell AG 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,167(3):433-445
Understanding the physiological and psychological factors that contribute to healthy and pathological balance control in man
has been made difficult by the confounding effects of the perturbations used to test balance reactions. The present study
examined how postural responses were influenced by the acceleration–deceleration interval of an unexpected horizontal translation.
Twelve adult males maintained balance during unexpected forward and backward surface translations with two different acceleration–deceleration
intervals and presentation orders (serial or random). “SHORT” perturbations consisted of an initial acceleration (peak acceleration
1.3 m s−2; duration 300 ms) followed 100 ms later by a deceleration. “LONG” perturbations had the same acceleration as SHORT perturbations,
followed by a 2-s interval of constant velocity before deceleration. Surface and intra-muscular electromyography (EMG) from
the leg, trunk, and shoulder muscles were recorded along with motion and force plate data. LONG perturbations induced larger
trunk displacements compared to SHORT perturbations when presented randomly and larger EMG responses in proximal and distal
muscles during later (500–800 ms) response intervals. During SHORT perturbations, activity in some antagonist muscles was
found to be associated with deceleration and not the initial acceleration of the support surface. When predictable, SHORT
perturbations facilitated the use of anticipatory mechanisms to attenuate early (100–400 ms) EMG response amplitudes, ankle
torque change and trunk displacement. In contrast, LONG perturbations, without an early deceleration effect, did not facilitate
anticipatory changes when presented in a predictable order. Therefore, perturbations with a short acceleration–deceleration
interval can influence triggered postural responses through reactive effects and, when predictable with repeated exposure,
through anticipatory mechanisms. 相似文献
49.
Tibor Hortobágyi Joseph A. Houmard Richard G. Israel John W. Carpenter Judy Heath Hisham A. Barakat 《European journal of applied physiology》1993,67(3):226-230
Summary The purpose of this study was to determine the effects of short-term exercise cessation on lipid and lipoprotein profile and insulin sensitivity in highly trained runners (n=12; mean age 19.9 years) and power athletes (n=12; mean age 24.4 years). Following 14 days of exercise cessation, running time to exhaustion and maximal oxygen uptake decreased by 9.2% and 4.8% (P < 0.05) in the runners, while in the power athletes one repetition maximum squat and bench press did not change (P>0.05). No changes occurred in body composition. Data from a 2-h oral glucose tolerance test revealed an impairment of the glycemic state in all athletes (P<0.05). In contrast, exercise cessation did not significantly (P>0.05) alter plasma levels of cholesterol, triglycerides, and low density (LDL) and high density lipoprotein (HDL). No changes were observed in HDL2, HDL2b, and HDL3 subfractions, LDL diameter, and qualitative LDL pattern (P>0.05). These data thus suggest that despite a decrease in insulin sensitivity, short-term exercise cessation, independent of exercise mode, was insufficient to alter plasma lipid and lipoprotein profiles in well-trained athletes. 相似文献
50.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献