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51.
52.
Microcephaly with or without chorioretinopathy, lymphoedema, or mental retardation (MCLMR) (MIM No.152950) is a rare autosomal dominant condition for which a causative gene has recently been identified. Mutations in the kinesin family member 11 (KIF11) gene have now been described in 16 families worldwide. This is a review of the condition based on the clinical features of 37 individuals from 22 families. This report includes nine previously unreported families and additional information for some of those reported previously. The condition arose de novo in 8/20 families (40%). The parental results were not available for two probands. The mutations were varied and include missense, nonsense, frameshift, and splice site and are distributed evenly throughout the KIF11 gene. In our cohort, 86% had microcephaly, 78% had an ocular abnormality consistent with the diagnosis, 46% had lymphoedema, 73% had mild-moderate learning difficulties, 8% had epilepsy, and 8% had a cardiac anomaly. We identified three individuals with KIF11 mutations but no clinical features of MCLMR demonstrating reduced penetrance. The variable expression of the phenotype and the presence of mildly affected individuals indicates that the prevalence may be higher than expected, and we would therefore recommend a low threshold for genetic testing.  相似文献   
53.
Automated blood glucose (BG) and insulin pump systems allow wireless transmission of all BG readings to a user’s pump. This study aimed to assess whether use of such a system, as compared with a manual BG entry insulin pump, resulted in higher mean daily frequency of BGs recorded after 6 months. A 12-month randomized crossover trial, comprising 2 phases, was conducted. All participants used insulin pump devices with automated vs manual BG entry for 6 months each; order of system use was randomly assigned. Device interactions were assessed from pump and glucometer downloads. Thirty-five participants were enrolled; 9 withdrew during the study. Use of the automated insulin pump system resulted in higher mean daily BG recorded over 6 months of use when compared to a manual BG entry system (5.8 ± 1.7 vs 5.0 ± 1.9; P = .02 [95% confidence interval, 0.14 to 1.58]). Bolus frequency was similar between groups. No HbA1c difference was observed between groups at 6 months (8.0% [64 mmol/l] ± 1.3 automated vs 7.7% [61 mmol/l] ± 0.9 manual; P = .38). Post hoc analysis demonstrated improved ΔHbA1c with automated system use in an adolescent subgroup with suboptimal baseline BG frequency (–0.9% vs + 0.5%; P = .003). Use of an automated glucometer/insulin pump resulted in higher number of BGs recorded over 6 months when compared to an insulin pump with manual BG entry. This may be especially beneficial for adolescent manual system users who enter <5 BGs per day into their pump.  相似文献   
54.
A variety of ecological processes influence diversity and species composition in natural communities. Most of these processes, whether abiotic or biotic, differentially filter individuals from birth to death, thereby altering species’ relative abundances. Nonrandom outcomes could accrue throughout ontogeny, or the processes that generate them could be particularly influential at certain stages. One long-standing paradigm in tropical forest ecology holds that patterns of relative abundance among mature trees are largely set by processes operating at the earliest life cycle stages. Several studies confirm filtering processes at some stages, but the longevity of large trees makes a rigorous comparison across size classes impossible without long-term demographic data. Here, we use one of the world’s longest-running, plot-based forest dynamics projects to compare nonrandom outcomes across stage classes. We considered a cohort of 7,977 individuals in 186 species that were alive in 1971 and monitored in 13 mortality censuses over 42 y to 2013. Nonrandom mortality with respect to species identity occurred more often in the smaller rather than the larger size classes. Furthermore, observed nonrandom mortality in the smaller size classes had a diversifying influence; species richness of the survivors was up to 30% greater than expected in the two smallest size classes, but not greater than expected in the larger size classes. These results highlight the importance of early life cycle stages in tropical forest community dynamics. More generally, they add to an accumulating body of evidence for the importance of early-stage nonrandom outcomes to community structure in marine and terrestrial environments.Processes that operate nonrandomly with respect to species identity contribute to the structure of natural communities (13). Evidence from diverse rain forests includes demographic transitions from seeds to seedlings (4, 5), at the seedling (6, 7) and sapling stages (8) and among large trees (912). Although the relative contributions of nonrandom processes at each life cycle stage to determining patterns of abundance and diversity in the mature canopy are unknown, one long-standing paradigm is that community assembly is mediated primarily by events occurring from seed dispersal through seedling germination and small-sapling establishment (1317). However, despite suggestive patterns (6, 7, 18, 19), evidence is lacking for the comparative strength of early-stage dynamics in determining canopy abundance and diversity.Numerous studies demonstrate significant interspecific variation in the susceptibility of tropical tree seedlings to postgermination hazards, including natural enemies (20, 21), adverse climatic or edaphic conditions (22), physical damage (23), and the crowding or shared-enemies effects of con- and heterospecific neighbors (24, 25). In other words, the per capita probability of seedling mortality is nonrandom because the probability of death is not the same for all individuals in a local community – it is dependent to some degree on species identity. In plant communities in which generation times are relatively short, experiments have demonstrated that nonrandom mortality through these early transitions can be sufficiently strong to affect the species composition of mature plants (2629). Such demonstrations are impossible in studies of a few decades or less in duration when generation times are long and even juveniles live for several decades or centuries, such as in many tropical forests. Even so, some hypotheses explicitly identify stressors that affect plants at the earliest life cycle stages (such as pests and pathogens, 13, 14, 30) as disproportionately influential. In addition, some empirical studies find a lack of support for nonrandom processes operating among larger stems (31, 32). Together these hypotheses and observations provide the rationale underpinning the considerable body of research on seed and seedling dynamics in tropical forests worldwide. However, no empirical or experimental assessment has been made of the relative contributions across life cycle stages from nonrandom mortality.Here, we evaluate the comparative contribution of early-stage dynamics using a multidecadal study of a tropical forest dynamics plot initiated by one of us (J.H.C.) in 1963 at a site in north Queensland, Australia. We considered a cohort of 7,977 individuals in 186 species that were alive on the plot in 1971, from tiny seedlings to large canopy trees, whose fates were monitored in 13 mortality censuses over 42 y to 2013. Individuals were assigned to one of six size classes (
Size class*N in 1971S in 1971S in 2013D in 2013 (% mortality)
SC1 (0-6.0-cm ht)1,46591241,421 (97.0)
SC2 (6.1–15.2-cm ht)1,275105471,156 (90.7)
SC3 (15.3–36.6-cm ht)1,29110677965 (74.7)
SC4 (36.7–182.9-cm ht)1,351124101639 (47.3)
SC5 (183.0-cm ht – 10-cm dbh)1,208135123330 (27.3)
SC6 (≥10.1-cm dbh)1,387122113357 (25.7)
Open in a separate windowS, number of species; N, number of stems alive in 1971; D, number of stems that died by 2013; dbh, diameter at breast height.*The original units of measurement on this plot were decimal inches and feet. Individuals < 3.2-inches girth have always been measured for height, to the nearest 0.1 ft. The upper height limits of size classes 1–4 are the metric equivalents of 0.2, 0.5, 1.2, and 6.0 ft.Our analyses proceeded in three stages. First, we determined the percentage, P, of species in each size class dying nonrandomly between 1971 and 13 progressively longer census periods to 2013. A species died nonrandomly within a given size class if the observed number of individuals dying over a census period was significantly different from the number of deaths expected under Monte Carlo simulations (10,000 runs) in which the probability of mortality was random with respect to species identity within the size class (i.e., “expected mortality”). Second, we determined for each census period and size class the effect of nonrandom mortality on the observed species richness of both the stems that survived (SS) and the stems that died (SD). From the simulations we generated means and 95% confidence limits for the expected numbers of survivors for each species in each size class in each census interval. We also calculated means and 95% confidence limits for the expected numbers of deaths for each species in each size class and census interval, as well as the means and 95% confidence limits for expected SS and SD. Third, we investigated frequency-dependent mortality as a potential mechanism explaining departures from expected species richness among observed survivors and the stems that died.  相似文献   
55.
APEX1 regulation of aldosterone synthase gene transcription is disrupted by a common polymorphism in humans     
McManus F  Sands W  Diver L  MacKenzie SM  Fraser R  Davies E  Connell JM 《Circulation research》2012,111(2):212-219
  相似文献   
56.
Traumatic dental injuries and their association with malocclusion in the primary dentition of Irish children     
Eimear Norton  Anne C. O’Connell 《Dental traumatology》2012,28(1):81-86
Abstract – Aims: This study sought to establish the prevalence of traumatic dental injuries in the primary dentition of Irish children and to investigate the relationship between dental trauma and non‐nutritive sucking habits. Materials and methods: Following ethical approval, a variety of schools and crèches in an urban setting were identified and parents of over 1000 children were contacted. Consent was obtained, and parental questionnaires were completed prior to a clinical examination of the children by one operator in a non‐dental setting. Signs of previous dental trauma were noted, and overbite and overjet were measured. Results: Eight hundred and thirty‐nine children were examined. The prevalence of dental trauma was 25.6%, with boys more frequently affected. The most commonly observed dental injury was fracture of enamel (39.4%), followed by crown discolouration (20.2%). Only 38.8% of the children with a reported history of trauma sought dental care. Non‐nutritive sucking habits were reported in 63.5% of the sample, and these habits, if prolonged, were significantly associated with anterior open bites and increased overjet (P < 0.001). Using regression analysis, it was established that the risk of dental injury is 2.99 times greater if the child has an overjet >6 mm and 2.02 times greater if the child has an anterior open bite. Conclusions: Non‐nutritive sucking habits are associated with the establishment of anterior open bite and increased overjet in the primary dentition. These malocclusions are, in turn, significantly associated with an increased prevalence of dental trauma in the primary dentition.  相似文献   
57.
Renal cell carcinoma metastases to gallbladder     
D McWhirter  M den Dulk  M Terlizzo  HZ Malik  SW Fenwick  GJ Poston 《Annals of the Royal College of Surgeons of England》2013,95(8):e136-e138
A 74-year old man underwent a radical cholecystectomy for presumed gallbladder cancer. The histology of the resected specimen in fact revealed the lesion to be metastatic renal cell carcinoma from his resected right nephrectomy performed 14 years previously.  相似文献   
58.
A presentation of Poncet's disease identified following immunosuppressive steroid therapy     
Kasivisvanathan V  Connell DW  Molyneaux PL  Singanayagam A  George PM  Tench C  Kon OM 《The international journal of tuberculosis and lung disease》2012,16(5):708-709
  相似文献   
59.
The Role of Ethnic Pride and Parental Disapproval of Smoking on Smoking Behaviors among Minority and White Adolescents in a Suburban High School     
G Kong  D Camenga  D Cavallo  CM Connell  JC Pflieger  S Krishnan-Sarin 《The American journal on addictions / American Academy of Psychiatrists in Alcoholism and Addictions》2012,21(5):424-434
Background: Adolescence is a critical developmental period when tobacco use is initiated and progression to regular smoking occurs. Another growing concern is the mounting evidence of ethnic/racial disparities in the smoking rates and adverse health consequences related to smoking. To reduce ethnic/racial disparities in smoking behaviors, understanding the protective influences against smoking behaviors among minority adolescents is important. Therefore, we examined the role of ethnic pride and parental disapproval of smoking on a wide range of smoking behaviors in ethnic/racial minority and White adolescents attending a suburban high school in Connecticut. Methods: A total of 870 adolescents (ethnic/racial minority: n= 202) completed questions on susceptibility to smoking, ever trying a cigarette, smoking at least one cigarette daily in the past 30 days, as well as parental disapproval of smoking and ethnic pride in a school-wide survey. Results: Logistic regression analyses indicated that perceived parental disapproval of adolescent smoking and ethnic pride were associated with susceptibility to smoking, ever trying a cigarette, and daily smoking differently for minority and White adolescents. For White youth, high parental disapproval of smoking was protective against all three smoking behaviors whereas ethnic pride was not. For minority youth, the combined protective effect of higher ethnic pride and higher parental disapproval of smoking was protective against all smoking behaviors. Conclusion: The protective role of parental disapproval of smoking and ethnic pride on smoking behaviors may inform culturally sensitive smoking interventions aimed at diverse, multi-ethnic youth, and future studies are needed to examine this. (Am J Addict 2012;21:424-434).  相似文献   
60.
An examination of healthy aging across a conceptual continuum: prevalence estimates, demographic patterns, and validity     
McLaughlin SJ  Jette AM  Connell CM 《The journals of gerontology. Series A, Biological sciences and medical sciences》2012,67(7):783-789
  相似文献   
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