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21.
Lymphokine-activated killer (LAK) cells can be focused at sites of tumor growth by products of macrophage activation 总被引:1,自引:0,他引:1
R J Migliori S A Gruber M D Sawyer R Hoffman A Ochoa F H Bach R L Simmons 《Surgery》1987,102(2):155-162
Successful adoptive cancer immunotherapy presumably depends on the accumulation of tumoricidal leukocytes at the sites of tumor growth. Large numbers of lymphokine-activated killer (LAK) cells can be generated in vitro by growth in high concentrations of interleukin-2 (IL-2), but relatively few arrive at the tumor site after intravenous injection. We hypothesize that the delivery of LAK cells to tumor sites may be augmented by previously demonstrated lymphocyte-recruiting factors, including activated macrophage products such as interleukin-1 (IL-1) and tumor necrosis factor. 111Indium-labeled LAK cells were injected intravenously into syngeneic mice bearing the macrophage activator endotoxin (LPS) in one hind footpad, and saline solution was injected into the contralateral footpad. Significantly more activity was recovered from the LPS-bearing footpad at all times during a 96-hour period. Recombinant IL-1 also attracted more LAK cells after injection into tumor-free hind footpads. Furthermore, LAK cells preferentially homed to hind footpads that were bearing 3-day established sarcomas after intralesional injections of LPS, IL-1, or tumor necrosis factor when compared with contralateral tumor-bearing footpads injected with saline solution alone. In preliminary experiments, mice with hind-footpad tumors appeared to survive longer after combined systemic IL-2 and LAK therapy if intralesional LPS was administered. These studies demonstrate that macrophage activation factors that have been shown capable of attracting circulating normal lymphocytes can also effectively attract LAK cells from the circulation. By the stimulation of macrophages at the sites of tumor growth, more LAK cells can be attracted. It is hoped that by "focusing" the migration of LAK cells to tumors, LAK cells and IL-2 would effect tumor regression more efficiently and with less toxicity. 相似文献
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Pyle MA Jasinevicius TR Lalumandier JA Kohrs KJ Sawyer DR 《General dentistry》1999,47(5):500-3; quiz 504-5
The occurrence of retromolar foramina (RMF) was examined in a sample of dry skulls (African American n = 249; Causcasian n = 226) to consider the potential clinical impact. A prevalence rate of 7.8% of RMF was found. There were no statistical differences based on race or gender. The prevalence may contribute to the explanation of a portion of inferior alveolar nerve block failures and provide insight into potential implications of surgery in the posterior mandible. 相似文献
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A domestic swine model was developed to examine the interaction of chemical warfare agents with anesthetics and other drugs used during general anesthesia. Animals were fully instrumented, and clinically relevant physiological parameters were monitored throughout the experimental procedures. Exposure of animals under halothane anesthesia to the chemical warfare agent sulfur mustard (HD; 1 mg/kg intravenous) produced mild signs of systemic intoxication during the subsequent 5 hours. Induction doses of ketamine 1 hour after HD exposure resulted in periods of profound apnea, with continued respiratory distress for the next 2 hours. When animals were treated with HD 1 hour after the initiation of ketamine anesthesia, severe and persistent convulsion-like muscular activity was observed within 45 minutes of HD administration. This nonpurposeful activity was not ameliorated by diazepam but was dramatically reduced or eliminated by resumption of halothane anesthesia. Treatment of HD-intoxicated pigs with succinylcholine produced a prolonged apnea resulting in death. In these apparently mildly HD-intoxicated animals, the introduction of ketamine or succinylcholine can rapidly induce potentially life-threatening situations. 相似文献
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Fifty five teenage girls with cystic fibrosis and their mothers were interviewed to assess the provision of sexual health information. Parents were the most common source of information for adolescents. The cystic fibrosis doctor was identified as the key resource for parents. Yet few parents had spoken to their doctor about these issues, and 96% requested more information. This information was wanted before puberty by mothers, and from puberty onwards by girls. 相似文献
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OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for =2 months. Women were more knowledgeable about OM signs and symptoms than about risk factors. Mean OM knowledge score (the sum of correct true-false responses) was 7.0 (standard deviation = 1.6). Using multiple linear regression, knowledge score was significantly related to marital status, education, age, area of residence, breastfeeding (months), and number of cigarettes smoked per day by the mother, but not to infant or sibling OM history or day care attendance (R = .23). Infant history of OM (odds ratio, 1.9; 95% confidence interval, 1.1 to 3.2) and white race (odds ratio, 0.3; 95% confidence interval, 0. 1 to 0.8), but not the presence of risk factors, were significantly related to having received clinicians' advice about OM prevention advice. CONCLUSION: OM education and prevention programs should target pregnant women and new mothers with OM risk factors, and those who are young, single, and less educated. 相似文献
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Michael G Sawyer Lauren Miller-Lewis Sophie Guy Melissa Wake Louise Canterford John B Carlin 《Ambulatory Pediatrics》2006,6(6):306-311
OBJECTIVE: To investigate the relationship between overweight and obesity, and mental health problems in Australian 4- to 5-year-old children. METHODS: The study used data from wave 1 (2004) of the Longitudinal Study of Australian Children (LSAC). The participants were 4983 4- to 5-year-old children (2537 boys and 2446 girls) with a mean age of 56.9 months (standard deviation 2.6 months; range 51-67 months). Children were classified as nonoverweight, overweight, and obese on the basis of International Obesity Task Force definitions. Mental health problems were assessed by the Strengths and Difficulties Questionnaire (SDQ) completed by parents and teachers. RESULTS: Although obese 4- to 5-year-old boys had more mental health problems than nonoverweight boys, differences between the groups were small and substantially reduced when analyses controlled for children's sociodemographic characteristics. Parents reported that overweight/obese girls had more peer problems, whereas teachers reported they had more conduct problems. Children in all weight groups had mean scores within the normal range of scores on all the SDQ subscales. CONCLUSIONS: Differences in rates of mental health problems experienced by young children of different weight status appear relatively small. Higher rates of mental health problems experienced by more obese boys may reflect differences in their sociodemographic characteristics rather than their weight status per se. Policies that reduce the number of young children living in poverty or experiencing other adverse social circumstances have the potential to reduce rates of mental health problems experienced by older children with overweight/obesity. 相似文献
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