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31.
Maximal oxygen consumption,pulmonary function,body composition,and anthropometry of adolescent female athletes 总被引:2,自引:0,他引:2
Ladislav P. Novak M. Bierbaum H. Mellerowicz 《European journal of applied physiology》1973,31(2):103-119
Three groups of girl athletes — 10 gymnasts and 8 middle-distance swimmers averaging 14 years of age, and 8 middle-distance runners averaging almost 19 — were the subjects of this study. The maximal oxygen intake was determined by graded work load on a bicycle ergometer, certain pulmonary functions by spirometry, and total body potassium by wholebody counting of naturally radioactive40K. The total body water was obtained from measurements of deuterium oxide and application of the dilution principle, and creatinine excretion was determined from urine collections. Fat-free mass was calculated from total body water, and the amount of body fat was obtained by subtracting fat-free mass from body weight. Cell mass was calculated from total body potassium. Supporting evidence of leanness or fatness was provided by anthropometric measurements.The runners and swimmers achieved significantly higher maximal oxygen consumption per kg of body weight, fat-free mass, and cell mass; and the runners excelled the gymnasts in certain other pulmonary functions. Total body potassium in milliequivalents per kg of body weight, total body water expressed in percentage of body weight, and creatinine coefficients were similar in all three groups of subjects. These results indicated no differences in body composition. Calculations of body fat, fat-free mass, and cellular mass verified that conclusion; and supporting evidence was obtained from subcutaneous fat folds and from appraisal of leanness by corrected limb diameters or volumes, which also were similar in all three groups. 相似文献
32.
Pal L; Leykin L; Schifren JL; Isaacson KB; Chang YC; Nikruil N; Chen Z; Toth TL 《Human reproduction (Oxford, England)》1998,13(7):1837-1840
A case series of eight cycles of in-vitro fertilization (IVF) in five women
diagnosed with malignant disorders is presented. These patients chose to
defer definitive treatment for a chance for preservation of potential
fertility. The response of these patients to ovarian stimulation, and the
outcome, was compared with 17 IVF cycles in 12 age- matched patients with
isolated tubal infertility. An apparent adverse influence of malignant
disease on the quality and behaviour of oocytes was observed. Despite a
comparable total number of oocytes per cycle in the two groups, a
significantly reduced percentage of mature oocytes was retrieved per cycle
from patients with malignant diseases. The oocytes from patients with
malignant disorders were of a poorer quality and exhibited a significantly
impaired fertilization rate compared to the controls. We propose that
neoplastic processes, irrespective of the site or cell of origin, may have
a detrimental impact on the biology of oocytes, an effect akin to that seen
on spermatozoa in men with certain malignancies.
相似文献
33.
Prevalence of Antibodies to Hepatitis E Virus in Veterinarians Working with Swine and in Normal Blood Donors in the United States and Other Countries 总被引:27,自引:0,他引:27
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X. J. Meng B. Wiseman F. Elvinger D. K. Guenette T. E. Toth R. E. Engle S. U. Emerson R. H. Purcell 《Journal of clinical microbiology》2002,40(1):117-122
Hepatitis E virus (HEV) is endemic in many developing and some industrialized countries. It has been hypothesized that animals may be the source of infection. The recent identification of swine HEV in U.S. pigs and the demonstration of its ability to infect across species have lent credence to this hypothesis. To assess the potential risk of zoonotic HEV infection, we tested a total of 468 veterinarians working with swine (including 389 U.S. swine veterinarians) and 400 normal U.S. blood donors for immunoglobulin G anti-HEV. Recombinant capsid antigens from a U.S. strain of swine HEV and from a human HEV strain (Sar-55) were each used in an enzyme-linked immunosorbent assay. The anti-HEV prevalence assayed with the swine HEV antigen showed 97% concordance with that obtained with the human HEV antigen (kappa = 92%). Among the 295 swine veterinarians tested from the eight U.S. states (Minnesota, Indiana, Nebraska, Iowa, Illinois, Missouri, North Carolina, and Alabama) from which normal blood donor samples were available, 26% were positive with Sar-55 antigen and 23% were positive with swine HEV antigen. In contrast, 18% of the blood donors from the same eight U.S. states were positive with Sar-55 antigen and 17% were positive with swine HEV antigen. Swine veterinarians in the eight states were 1.51 times more likely when tested with swine HEV antigen (95% confidence interval, 1.03 to 2.20) and 1.46 times more likely when tested with Sar-55 antigen (95% confidence interval, 0.99 to 2.17) to be anti-HEV positive than normal blood donors. We did not find a difference in anti-HEV prevalence between veterinarians who reported having had a needle stick or cut and those who had not or between those who spent more time (> or = 80% of the time) and those who spent less time (< or = 20% of the time) working with pigs. Similarly, we did not find a difference in anti-HEV prevalence according to four job categories (academic, practicing, student, and industry veterinarians). There was a difference in anti-HEV prevalence in both swine veterinarians and blood donors among the eight selected states, with subjects from Minnesota six times more likely to be anti-HEV positive than those from Alabama. Age was not a factor in the observed differences from state to state. Anti-HEV prevalence in swine veterinarians and normal blood donors was age specific and paralleled increasing age. The results suggest that swine veterinarians may be at somewhat higher risk of HEV infection than are normal blood donors. 相似文献
34.
35.
J. Toth C. Schultze-Werninghaus B. Marks A. F. P. Temmel P. Stübner S. Jäger F. Horak 《Allergy》1998,53(12):1172-1177
Background Preceding mucosal response to one allergen leads to the priming of the nasal mucosal response to another allergen. This study aimed t o determine whether environmental allergens, especially ubiquitous animal dander, can induce nasal priming.
Methods We investigated 26 grass-pollen-allergic subjects with additional sensitization to other aeroallergens. We performed continuous allergen challenge for 2 h with 1500 Dactylis glomerata pollen/m3 in the Vienna challenge chamber. The nasal flow at 150 Pa was examined, and subjective scores were obtained every 15 min. Statistical analysis was calculated from the area under curve of nasal flow reduction by Student's f-test and the Mann-Whitney U-test. Alpha was 0.05.
Results In subjects with positive cat-dander RAST (class of ≥ 3), besides grass-pollen allergy, the specific nasal allergic reaction to Dactylis challenge was significantly pronounced (P <0.01). and an earlier onset of reaction was evident. TTie same results were obtained with additional sensitization to dog dander (P<0.05). Concomitant sensitization to mugwort also led to escalating symptoms (P<0.05).
Conclusions These results indicate that a specific nasal allergic reaction is augmented by environmental priming caused by ubiquitous animal dander and possibly is influenced by the daily use of spices. 相似文献
Methods We investigated 26 grass-pollen-allergic subjects with additional sensitization to other aeroallergens. We performed continuous allergen challenge for 2 h with 1500 Dactylis glomerata pollen/m
Results In subjects with positive cat-dander RAST (class of ≥ 3), besides grass-pollen allergy, the specific nasal allergic reaction to Dactylis challenge was significantly pronounced (P <0.01). and an earlier onset of reaction was evident. TTie same results were obtained with additional sensitization to dog dander (P<0.05). Concomitant sensitization to mugwort also led to escalating symptoms (P<0.05).
Conclusions These results indicate that a specific nasal allergic reaction is augmented by environmental priming caused by ubiquitous animal dander and possibly is influenced by the daily use of spices. 相似文献
36.
B Toth 《Anticancer research》1985,5(5):457-469
The experimental techniques, methods of evaluation, and environmental implications of the findings of chemical carcinogenesis studies and related subject areas are herein critically reviewed. It is concluded that firstly, certain presently used procedures provide the best possibilities for the study of the hazardous nature of chemicals. Secondly, other matters, including the dosage of chemicals, animal species, meaning of the term "tumor induction", values of short-term tests, evaluation of tumor incidences, relation of the responses of humans and animals to carcinogenic stimuli, require new attitudes, innovative approaches, and meaningful changes. Thirdly, some of the issues are and will remain controversial until our basic knowledge substantially improves. Finally, it appears advisable to abandon some of the dogmatic attitudes for a more flexible approach. 相似文献
37.
Ladislav Novotný Hassan Farghali Miloš Ryba Ivo Janků Jiří Beránek 《Cancer chemotherapy and pharmacology》1984,13(3):195-199
Summary Both transport and biotransformation processes for a series of pyrimidine nucleobases, ribonucleosides, 2-deoxyribonucleosides, and acetyl and 5-substituted derivatives of the cancerostatic agent araC were studied in the isolated everted rat jejunum with a continuous perfusion technique. Metabolic alterations during penetration were assessed by HPLC. 5-Halogeno and 5-deoxy derivatives of cytosine nucleosides exhibited higher transport rates and higher stability towards the deamination reaction than did unsubstituted derivatives. Octanol-buffer partition coefficients were estimated for the study compounds, and fragmental constants for the sugar moieties of nucleosides were assessed. With the present study compounds there was no correlation between lipophilicity and transport rate, as previously reported, but there was a correlation between lipophilicity and metabolic alteration of araC derivatives (r=0.99, n=5). 相似文献
38.
Ladislav Pila Lucie Kvasni
kov Stanislavsk Roman Kvasni
ka Richard Hartman Ivana Tich 《Nutrients》2021,13(6)
Social media platforms have become part of many people’s lives. Users are spending more and more time on these platforms, creating an active and passive digital footprint through their interaction. This footprint has high research potential in many research areas because understanding people’s communication on social media is essential in understanding their values, attitudes, experiences and behaviors. Researchers found that the use of social networking sites impacts adolescents’ eating behavior. If we define adolescents as individuals between ages 10 and 24 (WHO’s definition), 76% of USA young people at age 18–24 use Instagram, so the Instagram social network analysis is important for understanding young people’s expressions in the context of healthy food. This study aims to identify the main topic associated with healthy food on the Instagram social network via hashtag and community analysis based on 2,045,653 messages created by 427,936 individual users. The results show that users most associate Healthy food with healthy lifestyle, fitness, weight loss and diet. In terms of food, these are foods that are Vegan, Homemade, Clean and Plant-based. Given that young people change their behavior in relation to people’s behavior on social networks, it is possible to use this data to predict their future association with healthy food characteristics. 相似文献
39.
40.
Lubna Pal Jan L. Shifren Keith B. Isaacson YuChiao Chang Lucy Leykin Thomas L. Toth 《Journal of assisted reproduction and genetics》1998,15(1):27-31
Purpose:
The impact of severity of endometriosis on the outcome of in vitro fertilization (IVF) was analyzed in an uncontrolled, retrospective study in an academic IVF program.
Methods:
Sixty-one patients with a primary diagnosis of endometriosis undergoing 85 cycles of IVF were included in the study. Patients were divided according to the severity of disease based on the revised American Fertility Society (AFS) classification into groups A (stages I/II, or minimal/mild) and B (stages III/IV, or moderate/severe). Group A included 32 patients undergoing 45 IVF-embryo transfer (ET) cycles; group B included 29 patients undergoing 40 IVF cycles. Exclusion criteria were age older than 40 years, basal day 3 follicle stimulating hormone (FSH) greater than 20 IU/L, male-factor infertility, assisted hatching, and gamete intrafallopian transfer cases. Stimulation for IVF cycles was standard using pituitary down-regulation with gonadotropin-releasing hormone agonist in a midluteal protocol. Controlled ovarian hyperstimulation (COH) was achieved using a combination of FSH and human menopausal gonadotropin. Outcomes assessed included response to COH and number, maturity, and quality of oocytes retrieved. Fertilization, implantation, and pregnancy rates after IVF-ET were also analyzed.
Results:
The response to COH and the number, maturity, and quality of the oocytes was comparable between patients with varying severity of endometriosis. Fertilization rates for oocytes of patients in group B (stages III/IV) were significantly impaired compared to those in group A (stages I/II) (P = 0,004). The rates for implantation, clinical pregnancy, and miscarriage were comparable between the two groups.
Conclusions:
The reduced fertilization potential of the oocytes obtained from patients with severe endometriosis in the absence of male-factor infertility suggests an adverse biological impact of the advanced disease on the oocytes. The outcome of IVF-ET, however, is unaffected by increasing severity of endometriosis. This suggests that IVF may compensate for or overcome this reduction in the biological potential of the oocytes associated with severe disease, thus accounting for a comparable outcome irrespective of the severity of endometriosis. 相似文献