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排序方式: 共有618条查询结果,搜索用时 15 毫秒
41.
Carbon M Kingsley PB Su S Smith GS Spetsieris P Bressman S Eidelberg D 《Annals of neurology》2004,56(2):283-286
We tested the hypothesis that the DYT1 genotype is associated with a disorder of anatomical connectivity involving primarily the sensorimotor cortex. We used diffusion tensor magnetic resonance imaging (DTI) to assess the microstructure of white matter pathways in mutation carriers and control subjects. Fractional anisotropy (FA), a measure of axonal integrity and coherence, was reduced (p < 0.005) in the subgyral white matter of the sensorimotor cortex of DYT1 carriers. Abnormal anatomical connectivity of the supplementary motor area may contribute to the susceptibility of DYT1 carriers to develop clinical manifestations of dystonia. 相似文献
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OBJECTIVE: To compare awake-sleep ambulatory blood pressure variation between Japanese-American and Caucasian women in Hawaii, specifically determining whether Japanese-Americans have reduced dipping of blood pressure during sleep, as is found in comparisons of Japanese and US samples. METHODS: Normotensive school teachers from East Hawaii who were either of Japanese-American (n = 70) or Caucasian (n = 48) ethnicity were recruited. They wore an ambulatory blood pressure monitor (Spacelabs 90207) that took measurements every 15 min during waking hours and every 30 min during sleep for a 24-h period on a normal workday. All subjects provided demographic information and underwent a series of anthropometric measurements the day before monitoring. Japanese-American subjects also answered questionnaires relating to cultural identity and migration history. RESULTS: The Japanese-American women had significantly higher mean diastolic (P < 0.01) blood pressure during sleep. These ethnic differences in sleep blood pressure persisted when analyses controlled for age, body mass index, and the waist-hip circumference ratio. There were also significant differences in the proportion by which blood pressure dipped from waking to sleeping, with the Japanese-American women dipping significantly less than the Caucasian women (P < 0.05 systolic, P < 0.001 diastolic). CONCLUSIONS: Normotensive Japanese-American women have higher sleep pressure, and a smaller awake-sleep dip, in pressure than Caucasian women. The relative elevation of blood pressure in Japanese-American women during sleep, but not at other times of the day, is similar to the pattern seen among Japanese women in Japan. 相似文献
44.
Hadden CE Sharaf MHM Guido JE Robins RH Tackie AN Phoebe CH Schiff PL Martin GE 《Journal of natural products》1999,62(2):238-240
A new alkaloid has been isolated from extracts of the West African plant Cryptolepis sanguinolenta and identified by submicro NMR techniques as 11-isopropylcryptolepine (1). The unusual incorporation of the isopropyl group at the 11-position of the indolo[3,2-b]quinoline nucleus is suggestive of a mixed biosynthetic origin for the alkaloid. 相似文献
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46.
To assess the radiosulfur colloid distribution in the liver-spleen scans of trauma patients, 73 trauma patients (age: 4-74 years, mean: 32 years) who had Tc-99m sulfur colloid liver-spleen scans for trauma workup were studied and compared with the liver-spleen scans of 87 control patients (age: 2-64 years, mean: 36 years). Radiocolloid distribution was visually assessed by two physicians independently, and the areas of the greatest density in the liver and spleen on the posterior view that included both organs were compared. The scans were grouped into three grades: Grade I, liver density greater than spleen density; Grade II, both organs showing equal density; and Grade III, splenic density greater than liver density (colloid shift). Forty-three of the trauma patients (59%) were in Grade III, 22 (30%) in Grade I, and 2 (11%) in Grade II. The control group had 12 (14%) patients in Grade III, 54 (62%) in Grade I, and 21 (24%) in Grade II. When the young adults and children of the trauma patients (age: 4-20 years, mean: 14 years) were looked at separately, 17 of 20 (85%) showed colloid shift (Grade III). It is concluded that there is a significantly higher incidence of colloid shift in trauma patients compared to control patients (P less than .01). 相似文献
47.
Phoebe Rich 《Dermatologic therapy》2001,14(3):228-236
The nail cosmetics industry is enormous, with $6.28 billion spent annually by consumers in the United States on salon services. Nail cosmetics provide the opportunity for women to camouflage unsightly nail conditions and improve the appearance of their nails. Most nail enhancements provide a coating over the nail plate to hide flaws. The coating can be a layer of nail enamel or one of the three main extension systems: acrylic sculptured nails, silk wraps, and ultraviolet (UV) polymerized acrylic gels. The end result is smooth, attractive, blemish-free nails. Adverse reactions to nail cosmetics and salon services are relatively uncommon and involve allergic, irritant, mechanical, and infectious problems. Nail cosmetic techniques are useful for disguising a variety of unsightly nail conditions. There are several conditions that may worsen in the presence of nail cosmetics. Because nail cosmetic use is so widespread, it is important for dermatologists to understand the procedures, materials, and rituals surrounding this industry. 相似文献
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49.
Alain Vonlaufena Phoebe A. Phillipsa Lu Yanga Zhihong Xua Eva Fiala-Beera Xuguo Zhanga Romano C. Pirola Jeremy S. Wilson Minoti V. Apte 《Pancreatology》2010,10(4):434-443
Background: Pancreatic stellate cells (PSCs) play a critical role in pancreatic fibrosis. To date, human PSC biology has been studied using cancer- or inflammation-associated (preactivated) PSCs, but an in vitro model of quiescent normal human PSCs (NhPSCs) has been lacking. Aims: To (i) isolate and characterize quiescent NhPSCs, and (ii) evaluate the response of culture-activated NhPSCs to cytokines and LPS. Methods: Quiescent NhPSCs were isolated from normal pancreatic tissue using density gradient centrifugation. PSC markers, glial fibrillary acidic protein (GFAP), desmin, α-smooth muscle actin (αSMA) and the lipopolysaccharide (LPS) receptors TLR4 and CD14 were identified by immunoblotting and immunocytochemistry. The effect of plateletderived growth factor (PDGF), transforming growth factor β (TGFβ) and LPS on NhPSC activation was also assessed. Results: Freshly isolated NhPSCs displayed a polygonal appearance with refringent cytoplasmic lipid droplets. Culture-activated NhPSCs expressed GFAP, desmin, αSMA, TLR4 and CD14, and were responsive to PDGF, TGFβ and LPS. Conclusion: Isolated NhPSCs expressed the same markers as rat PSCs and human cancer-associated PSCs and responded to PDGF and TGFβ similarly to rat PSCs. NhPSC preparations provide a useful in vitro tool to study the biology of PSCs in their physiological, non-activated state. 相似文献
50.
Kosoy R Nassir R Tian C White PA Butler LM Silva G Kittles R Alarcon-Riquelme ME Gregersen PK Belmont JW De La Vega FM Seldin MF 《Human mutation》2009,30(1):69-78
To provide a resource for assessing continental ancestry in a wide variety of genetic studies, we identified, validated, and characterized a set of 128 ancestry informative markers (AIMs). The markers were chosen for informativeness, genome-wide distribution, and genotype reproducibility on two platforms (TaqMan assays and Illumina arrays). We analyzed genotyping data from 825 subjects with diverse ancestry, including European, East Asian, Amerindian, African, South Asian, Mexican, and Puerto Rican. A comprehensive set of 128 AIMs and subsets as small as 24 AIMs are shown to be useful tools for ascertaining the origin of subjects from particular continents, and to correct for population stratification in admixed population sample sets. Our findings provide general guidelines for the application of specific AIM subsets as a resource for wide application. We conclude that investigators can use TaqMan assays for the selected AIMs as a simple and cost efficient tool to control for differences in continental ancestry when conducting association studies in ethnically diverse populations. 相似文献