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991.
992.
Trends in stillbirth rates, perinatal, neonatal and postneonatal mortality in Italy over the perrod 1955–84 were analyzed. There was a 75% reduction (from 28.4 to 7.1/1000 births) in stillbirth rates, and a nearly 70% fall (from 46.2 to 14.5/1000 births) in overall perinatal mortality (from the 180th day of pregnancy to the first week of life). Further, mortality rates from the 8th to the 28th day of life dropped from 7.4 to 1.6/1000 livebirths, and mortality from the second month to the first year of life from 25.1 to 2.2/1000 livebirths. The fall in stillbirth rates was similarly evident across various indicators of maternal education and social class, and could only marginally be accounted for by changes in maternal age distribution. The causes of this large drop in perinatal, neonatal and postneonatal mortality are likely to be numerous and complex. In the absence of any comprehensive program of rationalization of obstetrical and neonatal care, a determinant role must have been played by a general improvement in economic and cultural conditions. However, the observation that decreased perinatal mortality was not due to a decline in the proportion of low birth weight indicates that improved perinatal care may have had an important role as well. Although the decrease in various measures of perinatal and postneonatal mortality in Italy was proportionally comparable with that registered in several other developed countries, Italian perinatal mortality rates (14.5/1000 births in 1984) still appear considerably higher than in other countries, and are clearly far from the optimal theoretical value.  相似文献   
993.

Background  

Numerical rating scales (NRS), and verbal rating scales (VRS) showed to be reliable and valid tools for subjective cancer pain measurement, but no one of them consistently proved to be superior to the other. Aim of the present study is to compare NRS and VRS performance in assessing breakthrough or episodic pain (BP-EP) exacerbations.  相似文献   
994.
The static acute toxicities of 18 ionic liquids (ILs) were determined for three representative freshwater organisms, the cladoceran Daphnia magna, the green alga Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum), and the fish Danio rerio (formerly known as zebrafish). The test kit compounds contained three widely used ILs (1-butyl-3-methylimidazolium bis(triflimide), [bmim][Tf2N], butylpyridinium bis(triflimide), [bpy][Tf2N], and N,N-methylbutylpyrrolidinium bis(triflimide), [bmpyrr][Tf2N]) and 15 less common salts. These latter comprised a range of five anions, four positively charged head groups (ammonium, morpholinium, thiophenium, and sulfonium), five 1-methyl-3-alkyl imidazolium derivatives bearing a specific functional group on the longer alkyl chain (Cl, OH, or (CH3)3Si) and three imidazolium derivatives characterized by the presence of a hydrogen atom on the imidazolium nitrogen (“Brønsted acidic imidazolium”-based ILs). Generally, long-chain ammonium salts showed higher toxicity to algae, cladocerans, and fish, whereas very low toxicities characterized sulfonium- and morpholinium-based ILs. In imidazolium-based ILs, the substitution of one or two carbon atoms of the longer alkyl chain with a more electronegative atom (chlorine or oxygen) reduced the acute toxicity for algae and cladocerans. Low toxicity also characterized the “Brønsted acidic imidazolium”-based ILs. Structural information for a rational designer of safer ILs can be obtained from these studies.  相似文献   
995.
New promising compounds, derived from the esterification of hyaluronic acid with butyric acid, were investigated in vitro on a non-small cell lung carcinoma cell line (NCI-H460) and an its metastatic subclone (NCI-H460M). All new compounds exerted a dose-dependent inhibitory effect on both cell lines, which expressed CD44, the specific surface receptor for hyaluronic acid, in a very high percentage of cells (90%). HE1, the most effective of these compounds, was 10-fold more effective than sodium butyrate (NaB) in inhibiting cell proliferation. Similarly to NaB, after 24 hours of treatment, HE1 affected the expression of three cell cycle-related proteins (p27(kip1), p53 and p21(waf1)) responsible for growth arrest, indicating that the presence of the hyaluronic acid backbone does not interfere with the biologic activity. Intratumoral treatment with HE1 demonstrated a marked efficacy on primary tumor growth and on lung metastases formation of the murine Lewis Lung Carcinoma model. Altogether, present findings suggest a possible clinical application of these novel butyric pro-drugs in primary and metastatic lung cancer.  相似文献   
996.
To evaluate familial aggregation of inflammatory bowel disease (IBD) in the Mediterranean area and to estimate the disease risk in first degree relatives. 427 patients with IBD were consecutively interviewed in order to obtain a complete pedigree of first degree relatives. Sufficient information was obtained in 98% of 2,685 family members. The prevalence ratio of IBD in family members was estimated and compared to the prevalence ratio of IBD in general population; the ratio was then standardized by age since the prevalence of the disease is age-dependent. The lifetime risk was assessed by the Kaplan Meier method. Thirty index cases (7%) had at least one affected first degree relative. As compared with the general population, first degree relatives of the 427 patients with IBD had a 4.38-fold increase in the age corrected risk of having the same disease. The Kaplan-Meier curve showed a higher risk at 25 years of age for offsprings (3%) than for parents (1%) and siblings (1%) whereas the crude ratio showed a higher risk for siblings (1.9%) compared to parents (0.8%) and offsprings (1%). In the Mediterranean area, the familial prevalence of IBD is higher than in the general population and comparable to North European rates.Abbreviations CD Crohn's disease - IBD inflammatory bowel disease - UC ulcerative colitis  相似文献   
997.
An epidemiological study on the urinary tract anomalies (UTA) associated with other congenital malformations or syndromes ascertained by the Emilia-Romagna Registry on Congenital Malformations (IMER) among 209,882 consecutive births monitored during the period 1981–1990 is presented. UTA were ascertained in 349 infants for a rate at birth of 16.6 per 10,000 total births, or one case for every 600 births. The occurrence rate of UTA increased significantly during the ten years of monitoring passing from 6.1 per 10,000 in 1981–1982 to 25.1 in 1989–1990 (r = 0.85; p < 0.001). This increase is in connection with a progressively higher notification of isolated cases of UTA, directly related to the impact of the prenatal diagnosis. Among the 349 cases, 106 (30.4%) were associated with other conditions, including 18 who had chromosomal aberrations (ChrA). The incidence in the total number of the ChrA registered was 43.6 per 1,000. Genetic syndromes (GS) in 33 cases with a specific rate of 150 per 1,000; and 55 cases of multiples with a specific rate of 205.2 per 1,000. In multiples we observed some preferential associations of UTA with intestinal defects and severe ear defects (p < 0.001) and for Central Nervous System and heart defects (p < 0.05). UTA are often associated with other extrarenal defects and sometimes are a component of syndromes that are difficult to identify and for which genetic implications are great and genetic counselling necessary. Pediatricians need to be aware of the possible involvement of the kidney in specific and rare syndromes, and pediatric nephrologists must recognize the association of renal diseases with abnormalities in other physiological systems.  相似文献   
998.
Sediments from the Venice lagoon, a polluted coastal environment in northeastern Italy, were assayed for mutagenicity and content of several toxic microcontaminants, which included selected polycyclic aromatic hydrocarbons (PAHs); the latter are specifically dealt with in this paper. Samples were collected at three lagoon sites with reasonably distinct environmental features—urban, industrial, or agricultural—and at two others considered to be under mixed pollution influences; a sixth sample was obtained from an open sea area to act as background control. The organic matter (EOM) associated with the mineral substrata was extracted; after cleanup, analyte determination was carried out by HRGC-LRMS(SIM) using isotopically labeled compounds as internal standards. Cumulative levels of the selected PAHs were found to be in the range of 0.065 to 0.46 μg/g of dry matrix at five sites; a much higher concentration (48 μg/g) was detected in the sample from the urban environment. The remarkable PAH level increase at this site was mostly accounted for by the concurrent, apparent increase of EOM contamination as PAH concentration was seen to reach 32 μg/mg of EOM from <1 μg/mg at the five remaining sites. Mutagenicity assays withSalmonella typhimuriumstrains TA98 and TA100 of marine sediment organic extracts also highlighted a distinct activity in the sample from the urban site. Further fractionation and analysis of this extract pointed to PAHs as the main mutagenic component present in the sediment matrix, possibly accounting for up to approximately 70–80% of the entire mutagenic potential detected.  相似文献   
999.
Classic hereditary hemochromatosis (HH) is a common genetic disorder of iron metabolism caused by a mutation in the HFE gene. Whereas the prevalence of the mutation is very high, the clinical penetrance of the disease is low, suggesting that the HFE mutation is a necessary but not sufficient cause of clinical HH. Several candidate modifier genes have been proposed in mice and humans, including haptoglobin. Haptoglobin is the plasma protein with the highest binding affinity for hemoglobin. It delivers free plasma hemoglobin to the reticuloendothelial system, thus reducing loss of hemoglobin through the glomeruli and allowing heme-iron recycling. To gain insight into the role of haptoglobin as a modifier gene in HH, we used Hfe and haptoglobin double-null mice. Here, we show that Hfe and haptoglobin compound mutant mice accumulate significantly less hepatic iron than Hfe-null mice, thus demonstrating that haptoglobin-mediated heme-iron recovery may contribute significantly to iron loading in HH.  相似文献   
1000.
Folliculitis spinulosa decalvans is an uncommon condition characterized by follicular hyperkeratosis, followed by scarring alopecia. We report a 12-year-old boy affected by keratotic papules of the scalp and keratosis pilaris of the limbs who developed erythema, pustules, and scale crusts on the scalp associated with scarring alopecia. Histologic examination showed follicular and interfollicular hyperkeratosis, follicular plugging, mild inflammation, and focal scarring. A transient remission of the inflammatory changes on the scalp was obtained after treatment with isotretinoin. The follicular spinulous hyperkeratosis persisted. A severe relapse of the scalp inflammation was observed during a 2-year follow-up.  相似文献   
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