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21.

Background

The impact of gender on the staging and prognosis of urothelial carcinoma of the bladder (UCB) is insufficiently understood.

Objective

To assess gender-specific differences in pathologic factors and survival of UCB patients treated with radical cystectomy (RC).

Design, setting, and participants

Data from 8102 patients treated with RC (6497 men [80%] and 1605 women [20%]) for UCB between 1971 and 2012 were analyzed.

Outcome measurements and statistical analysis

Multivariable competing-risk regression analyses were performed to evaluate the relationship of gender on disease recurrence (DR) and cancer-specific mortality (CSM). We also tested the interaction of gender and tumor stage, nodal status, and lymphovascular invasion (LVI).

Results and limitations

Female patients were older at the time of RC (p = 0.033) and had higher rates of pathologic stage T3/T4 disease (p < 0.001). In univariable, but not in multivariable analysis, female gender was associated with a higher risk of DR (p = 0.022 and p = 0.11, respectively). Female gender was an independent predictor for CSM (p = 0.004). We did not find a significant interaction between gender and stage, nodal metastasis, or LVI (all p values >0.05).

Conclusions

We found female gender to be associated with a higher risk of CSM following RC. However, these findings do not appear to be explained by gender differences in pathologic stage, nodal status, or LVI. This gender disparity may be due to differences in care and/or the biology of UCB.  相似文献   
22.
Health literacy (HL) research among Hispanics currently focuses on individuals with limited English proficiency but impacts of HL on healthcare outcomes among other English language proficiency groups is relatively unknown. Regression models assessed associations between HL and healthcare outcomes for Hispanics overall (n = 4013) and for proficiency level sub-populations using the 2007 Pew Hispanic Health Survey. Overall, Hispanics with adequate HL percieved US medical care as “excellent,” were more satisfied with their doctor’s help, and reported “excellent” overall health. In the sub-population analysis, “excellent” perception of US healthcare was associated with HL among the Spanish and English dominant groups. Among bilinguals, adequate HL was associated with decreased use of traditional medicine. The effect of adequate HL varied within English proficiency groups. HL research that focuses only on Spanish dominant speakers can exclude a substantial percentage of English proficient or bilingual populations who have low HL.  相似文献   
23.
Coumarins and coumestans represent an important family of compounds with diverse pharmacological properties. We recently identified coumestans as novel inhibitors of hepatitis C virus NS5B polymerase and predicted their binding in thumb pocket‐1 (TP‐1) of NS5B. As the coumarins are structurally related to coumestans by virtue of their common A‐ and B‐rings, we postulated them to also exhibit similar binding interaction with NS5B and inhibit its polymerase function. We therefore investigated 24 coumarin and neoflavone derivatives as candidate NS5B inhibitors and identified 14 compounds inhibiting NS5B polymerase activity with IC50 values between 17 and 63 μm . Of these, the newly synthesized 6,8‐diallyl‐5,7‐dihydroxycoumarin ( 8a ) was produced in three steps in high chemical yield from floroglucinol and found to be the most potent of this series, exhibiting activity similar to the reference coumestan LQB‐ 34 . The binding site of 8a was mapped to TP‐1 of NS5B by counter screening against P495L NS5B mutant, employed as a screen for TP‐1 site binders. NS5B‐TP‐1‐ 8a interaction map provided insight into 8a binding and offered clues for future SAR optimization.  相似文献   
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25.
Contactins are a group of cell adhesion molecules that are mainly expressed in the brain and play pivotal roles in the organization of axonal domains, axonal guidance, neuritogenesis, neuronal development, synapse formation and plasticity, axo-glia interactions and neural regeneration. Contactins comprise a family of six members. Their absence leads to malformed axons and impaired nerve conduction. Contactin mediated protein complex formation is critical for the organization of the axon in early central nervous system development. Mutations and differential expression of contactins have been identified in neuro-developmental or neurological disorders. Taken together, contactins are extensively studied in the context of nervous system development. This review summarizes the physiological roles of all six members of the Contactin family in neurodevelopment as well as their involvement in neurological/neurodevelopmental disorders.  相似文献   
26.
The experiments reported here were designed for both in vivo and in vitro approaches in the same animals to obtain a better picture of the role of estrogen in the control of parturition. Chronically catheterized pregnant ewes were treated with vehicle (n = 5) or estradiol (n = 6), 5 mg twice a day, im for 2 d starting at d 119 of gestation. Maternal and fetal plasma estradiol, progesterone, and cortisol were measured by RIA and maternal plasma prostaglandin (PG) F2alpha was measured by enzyme immunoassay. Intrauterine PG H synthase 2 mRNA and protein and placental P450(c17)alpha hydroxylase mRNA were determined by Northern, in situ hybridization, Western blot analysis, and immunocytochemistry. Data were analyzed by ANOVA.Five of six estradiol-treated ewes delivered their fetuses within 48 h; however, the placenta was still retained 5-6 h after fetal delivery. Both maternal plasma estradiol and PGF2 alpha increased significantly in the estradiol-treated group. Maternal and fetal plasma progesterone and cortisol were not altered in either group. There were significant increases of PGH synthase 2 mRNA and protein in myometrium, endometrium, and maternal placenta but not in fetal placenta in estradiol-treated ewes. Placental P450(c17)alpha hydroxylase mRNA was not detectable in vehicle or estradiol-treated groups.Estradiol can, in the absence of increase in plasma cortisol, stimulate uterine PG production and induce labor, resulting in fetal delivery in the sheep. Failure of placental delivery after estradiol treatment suggests that estradiol alone is insufficient to stimulate some of the key changes required to complete delivery at the stage of gestation studied.  相似文献   
27.
28.
Understanding the conductivity variations induced by compositional changes in sodium super ionic conducting (NASICON) glass materials is highly relevant for applications such as solid electrolytes for sodium (Na) ion batteries. In the research reported in this paper, NASICON-based NCAP glass (Na2.8Ca0.1Al2P3O12) was selected as the parent glass. The present study demonstrates the changes in the Na+ ion conductivity of NCAP bulk glass with the substitution of boron (NCABP: Na2.8Ca0.1Al2B0.5P2.7O12) and gallium (NCAGP: Na2.8Ca0.1Al2Ga0.5P2.7O12) for phosphorus and the resulting structural variations found in the glass network. For a detailed structural analysis of NCAP, NCABP and NCAGP glasses, micro-Raman and magic angle spinning-nuclear magnetic resonance (MAS-NMR) spectroscopic techniques (for 31P, 27Al, 23Na, 11B and 71Ga nuclei) were used. The Raman spectrum revealed that the NCAP glass structure is more analogous to the AlPO4 mesoporous glass structure. The 31P MAS-NMR spectrum illustrated that the NCAP glass structure consists of a high concentration of Q0 (3Al) units, followed by Q0 (2Al) units. The 27Al MAS-NMR spectrum indicates that alumina exists at five different sites, which include AlO4 units surrounded by AlO6 units, Al(OP)4, Al(OP)5, Al(OAl)6 and Al(OP)6, in the NCAP glass structure. The 31P, 27Al and 11B MAS-NMR spectra of the NCABP glass revealed the absence of B–O–Al linkages and the presence of B3–O–B4–O–P4 linkages which further leads to the formation of borate and borophosphate domains. The 71Ga MAS-NMR spectrum suggests that gallium cations in the NCAGP glass compete with the alumina cations and occupy four (GaO4), five (GaO5) and six (GaO6) coordinated sites. The Raman spectrum of NCAGP glass indicates that sodium cations have also been substituted by gallium cations in the NCAP glass structure. From impedance analysis, the dc conductivity of the NCAP glass (∼3.13 × 10−8 S cm−1) is slightly decreased with the substitution of gallium (∼2.27 × 10−8 S cm−1) but considerably decreased with the substitution of boron (∼1.46 × 10−8 S cm−1). The variation in the conductivity values are described based on the structural changes of NCAP glass with the substitution of gallium and boron.

Understanding the conductivity variations induced by compositional changes in sodium super ionic conducting (NASICON) glass materials is highly relevant for applications such as solid electrolytes for sodium (Na) ion batteries.  相似文献   
29.
Objectives. We investigated the development of and service utilization at Supporting Positive Opportunities with Teens (SPOT)—a community-based health and social service facility in St. Louis, Missouri, for youths that focuses on increasing HIV and sexually transmitted infection (STI) testing.Methods. We identified the US-based, co-located youth health and social service models that guided the establishment of the SPOT. We analyzed the first 5 years (2008–2013) of service delivery and utilization data.Results. During the study period, the SPOT provided services for 8233 youths in 37 480 visits. The 5 most utilized services included HIV and STI screening, food, transportation, contraception, and case management. A total of 9812 gonorrhea and chlamydia screenings revealed 1379 (14.1%) cases of chlamydia and 437 (4.5%) cases of gonorrhea, and 5703 HIV tests revealed 59 HIV infections (1.0%); 93.0% of patients found to have an STI were treated within a 5-day window.Conclusions. Co-locating health and social services in informal community settings attracts high-risk youths to utilize services and can prove instrumental in reducing STI burden in this population.Sexual behaviors that contribute to unintended pregnancy and sexually transmitted infections (STIs), including HIV, are considered a priority health-risk behavior among youths in the United States.1 In 2008, St. Louis, Missouri, had some of the highest rates of Neisseria gonorrheae and Chlamydia trachomatis infections of all US cities.2 The majority of STIs in youths aged 15 to 24 years in Missouri are seen disproportionately among African American youths. HIV infection rates among youths continue to rise.3 From 2008 to 2010 new cases of HIV/AIDS among male youths in St. Louis increased by 33%, compared with a 2% increase among adult males.3,4These high rates of STIs and HIV highlight gaps in services for youths in our region. Evidence suggests that it is best to co-locate health and social services when providing care to a very needy population of youths.5–7 There are programs that do this in multiple sites across the country. Studies found that peer-to-peer information sharing and outreach, peer advisory groups, tightly linked medical and social services, and active case management to assess need and link youths to services were critical for keeping youths engaged.6,7 Despite the obvious needs of youths in St. Louis, no social service agency or health facility has ever combined these services for youths aged 13 to 24 years.We describe the development of our youth center, the SPOT (Supporting Positive Opportunities with Teens), and report screening outcomes and service utilization measures for the first 5 years of the center. We focus on identifying STI and HIV infections in youths and ensuring access to timely treatment.  相似文献   
30.
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