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61.
Levels of rotavirus-specific immunoglobulin G (IgG), IgA, IgM, and secretory immunoglobulin in maternal and cord serum, colostrum and milk, and infants' stools were measured by enzyme-linked immunosorbent assay in 92 mothers and their infants. Although antirotaviral IgG, IgA, and secretory immunoglobulin were present in most maternal sera, only IgG crossed the placenta. All samples of colostrum and milk tested contained antirotaviral secretory immunoglobulin and IgA except those of two women in whom IgA deficiency was subsequently described. Specific IgM and IgG were also detected in many colostral samples. Antirotaviral IgA was detected in many colostral samples. Antirotaviral IgA was detected in stools of breast-fed but not bottle-fed neonates. Apparently the human infant receives rotaviral antibodies both transplacentally and via maternal colostrum and milk. 相似文献
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In 34 studies on six "upright" anesthetized sheep central venous pressure from sites in the upper and lower superior vena cava (SVC) was recorded before, during, and after the injection into a neck vein of 1-ml increments of air every minute for 15 min. After the injection of air, the pressure recorded from the upper site increased significantly. This increase was the result of air collecting in the SVC with a consequent loss or partial loss of the SVC hydrostatic pressure difference. The time of onset and the duration of collection were not influenced by hyper- or hypovolemia nor by 1 kPa positive end-expiratory pressure. The readily identifiable change in the venous pressure in the upper SVC provided an earlier and more reliable warning of these small-volume air emboli than did a Doppler probe directed at the right side of the heart. 相似文献
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Summary The mechanism of quinidine action on rabbit cardiac and skeletal muscle was examined with functionally skinned muscle-fiber preparations. By using these preparations we could correlate measurements of muscle tension with the effect of quinidine on the Ca2+ activation of the contractile proteins and on the Ca2+ uptake and release from the sarcoplasmic reticulum (SR).
Effect of quinidine on the contractile proteins. Quinidine concentrations above 0.5 mmol/l increased the maximal Ca2+-activated tension development 12% for papillary muscle and 5% for soleus (slow-twitch). Adductor magnus (fast-twitch) showed no significant change. Quinidine (0.1–1.0 mmol/l) also increased the submaximal Ca2+-activated tension development for the three muscle types (papillary muscle=soleus>adductor magnus) and shifted the [Ca2+]-tension curves to the left in a dose-dependent fashion.
Effects of quinidine on the Ca
2+ uptake and release from the SR. Sarcoplasmic reticulum of skinned fibers was loaded with Ca2+ (uptake phase), then Ca2+ was released by 25 mmol/l caffeine (release phase) giving a tension transient. The area under the tension transient was used to estimate the amount of Ca2+ released. Quinidine (>0.5 mmol/l) decreased the Ca2+ uptake (soleus>adductor magnus>papillary muscle) and increased the Ca2+ release [papillary muscle=soleus adductor magnus (only at 1.5 mmol/l, the highest concentration tested)] from the SR of all three muscles in a dose-dependent manner. Quinidine at low concentration (0.1 and 0.5 mmol/l) increased the caffeine-induced tension transient of papillary muscle and higher quinidine concentrations (1.0 and 1.5 mmol/l) decreased the caffeine-induced tension transient of soleus and adductor magnus during both the uptake and release phases. The decreased Ca2+ uptake of papillary muscle in 1.5 mmol/l quinidine was antagonized by increasing the free Mg2+ from 0.032 to 0.32 mmol/l.In summary, quinidine has similar mechanisms of action in all three muscles: increased Ca2+ activation of the contractile proteins, decreased Ca2+ uptake and increased Ca2+ release from the SR in functionally skinned muscle fibers. We conclude that quinidine-induced decreases in Ca2+ uptake by the SR could be responsible for quinidine-induced myocardial depression and that quinidine-induced increases in Ca2+ activation of the contractile proteins and Ca2+ release from the SR could be responsible for the increases in skeletal muscle contraction caused by quinidine. 相似文献
67.
Ryan Gage Martin Girling-Butcher Ester Joe Moira Smith Cliona Ni Mhurchu Christina McKerchar Viliami Puloka Rachael McLean Louise Signal 《Nutrients》2021,13(1)
Snacking is a common eating behaviour, but there is little objective data about children’s snacking. We aimed to determine the frequency and context of children’s snacking (n = 158; mean age = 12.6 years) by ethnicity, gender, socioeconomic deprivation and body mass index (BMI) children. Participants wore wearable cameras that passively captured images of their surroundings every seven seconds. Images (n = 739,162) were coded for snacking episodes, defined as eating occasions in between main meals. Contextual factors analysed included: snacking location, food source, timing, social contact and screen use. Rates of total, discretionary (not recommended for consumption) and healthful (recommended for consumption) snacking were calculated using negative binomial regression. On average, children consumed 8.2 (95%CI 7.4, 9.1) snacks per day, of which 5.2 (95%CI 4.6, 5.9) were discretionary foods/beverages. Children consumed more discretionary snacks than healthful snacks in each setting and at all times, including 15.0× more discretionary snacks in public spaces and 2.4× more discretionary snacks in schools. Most snacks (68.9%) were sourced from home. Girls consumed more total, discretionary and healthful snacks than boys, and Māori and Pacific consumed fewer healthful snacks than New Zealand (NZ) Europeans. Results show that children snack frequently, and that most snacking involves discretionary food items. Our findings suggest targeting home buying behaviour and environmental changes to support healthy snacking choices. 相似文献
68.
Winnie K. W. So Judy Y. W. Chan Bernard M. H. Law Kai Chow Choi Jessica Y. L. Ching Kam Leung Chan Raymond S. Y. Tang Carmen W. H. Chan Justin C. Y. Wu Stephen K. W. Tsui 《Nutrients》2021,13(2)
Rice bran exhibits chemopreventive properties that may help to prevent colorectal cancer (CRC), and a short-term rice bran dietary intervention may promote intestinal health via modification of the intestinal microbiota. We conducted a pilot, double-blind, randomised placebo-controlled trial to assess the feasibility of implementing a long-term (24-week) rice bran dietary intervention in Chinese subjects with a high risk of CRC, and to examine its effects on the composition of their intestinal microbiota. Forty subjects were randomised into the intervention group (n = 19) or the control group (n = 20). The intervention participants consumed 30 g of rice bran over 24-h intervals for 24 weeks, whilst the control participants consumed 30 g of rice powder on the same schedule. High rates of retention (97.5%) and compliance (≥91.3%) were observed. No adverse effects were reported. The intervention significantly enhanced the intestinal abundance of Firmicutes and Lactobacillus, and tended to increase the Firmicutes/Bacteroidetes ratio and the intestinal abundance of Prevotella_9 and the health-promoting Lactobacillales and Bifidobacteria, but had no effect on bacterial diversity. Overall, a 24-week rice bran dietary intervention was feasible, and may increase intestinal health by inducing health-promoting modification of the intestinal microbiota. Further larger-scale studies involving a longer intervention duration and multiple follow-up outcome assessments are recommended. 相似文献
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Ari Whiteman Alice Wang Kelly McCain Betsy Gunnels Robin Toblin James Tseryuan Lee Carolyn Bridges Laura Reynolds Bhavini Patel Murthy Judy Qualters James A. Singleton Kimberley Fox Shannon Stokley LaTreace Harris Lynn Gibbs-Scharf Neetu Abad Kathryn A. Brookmeyer Susan Farrall Cassandra Pingali Anita Patel Ruth Link-Gelles Sharoda Dasgupta Radhika Gharpure Matthew D. Ritchey Kamil. E. Barbour 《MMWR. Morbidity and mortality weekly report》2021,70(19):725