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91.
BACKGROUND: Data on the association of n-3 fatty acid content in serum lipids with mortality in patients with coronary artery disease (CAD) are limited. OBJECTIVE: We hypothesized that a high proportion of n-3 fatty acids in serum lipids would be associated with reduced risks of death and coronary events in patients with established CAD. DESIGN: We measured dietary intakes via food records and the fatty acid composition of serum cholesteryl esters (CEs) in 285 men and 130 women with CAD (x age: 61 y; range: 33-74 y). The patients participating in the EUROASPIRE (European Action on Secondary Prevention through Intervention to Reduce Events) study were followed up for 5 y. RESULTS: During the follow-up, 36 patients died, 21 had myocardial infarctions, and 12 had strokes. The relative risks (RRs) of death adjusted for cardiovascular disease risk factors for subjects in the highest tertile of fatty acids in CEs compared with those in the lowest tertile were 0.33 (95% CI: 0.11, 0.96) for alpha-linolenic acid, 0.33 (0.12, 0.93) for eicosapentaenoic acid, and 0.31 (0.11, 0.87) for docosahexaenoic acid (P for trend = 0.063, 0.056, and 0.026, respectively). A high proportion of eicosapentaenoic acid in CEs was associated with a low risk of CAD death. Compared with no consumption, consumption of fish tended to be associated with a lower risk of death [1-57 g/d, RR = 0.50 (0.20, 1.28); > 57 g/d, RR = 0.37 (0.14, 1.00); P for trend = 0.059]. CONCLUSION: High proportions of n-3 fatty acids in serum lipids are associated with a substantially reduced risk of death.  相似文献   
92.
Significantly increased up-regulation of HLA DR (major histocompatibility complex class II antigen) was seen using immunohistochemistry in postmortem brain tissue from demented patients with Alzheimer’s disease (AD) (73 cases, 61 females/12 males, mean age 84 ± 9 years) compared to controls (22 cases, 10 females/12 males, mean age 78 ± 9 years). The counts of HLA DR-expressing activated microglia were significantly higher in female AD patients compared to males, significantly higher in AD patients with the age at death greater than 75 years compared to those dying younger and higher, although not statistically significantly, in AD patients with the apolipoprotein E (ApoE) ɛ4 allele compared to those patients not carrying this allele. In contrast to the situation in AD patients, in the control cases the HLA DR expression was higher in males compared to females. Furthermore, in the very old non-demented patients (age at death > 80 years), a decrease in the up-regulation of HLA DR expression was observed. A significant correlation between activated microglia and neurofibrillary tangles was seen in female AD patients compared to males, in AD cases without ApoE ɛ4 allele compared to those with this allele, in sporadic cases compared to familial and in cases with senile rather than presenile onset of the disease. Our results indicate that there is an age- and/or sex-related variability in up-regulation of HLA DR expression of microglia and that the linkage between this up-regulation and AD lesions is significantly influenced by the ApoE ɛ4 allele, gender of subjects, age at onset and familiality of the disease. Received: 20 May 1998 / Revised: 5 August 1998, 4 October 1998 / Accepted: 21 October 1998  相似文献   
93.
94.
Cis-9, trans-11, the major isomer of conjugated linoleic acid (CLA) in bovine milk fat, is derived from ruminal biohydrogenation of 18:2 (n-6) and endogenous conversion of trans-11 18:1 (vaccenic acid; VA) in the mammary gland. Most evidence to date suggests that endogenous synthesis is the major source of cis-9, trans-11 CLA, but the extent of VA desaturation is less well defined. Four lactating cows were used in consecutive 4 x 4 Latin squares to examine changes in milk fatty acid composition and secretion in response to abomasal infusions of lipid supplements enriched with cis-9, trans-11 CLA (88.8%) or VA (29.4%). Treatments were infused over 4-d, followed by a 3-d washout, during 7 d experimental periods and administered to deliver 0, 3, 6, and 12 g cis-9, trans-11 CLA/d (Expt. 1) or 0, 7.5, 15 and 30 g VA/d (Expt. 2). Infusions of cis-9, trans-11 CLA increased linearly milk cis-9, trans-11 CLA concentrations from 0.68 to 1.46 g/100 g fatty acids. Abomasal infusions of VA increased linearly milk VA and cis-9, trans-11 CLA content from 1.22 to 2.72 and 0.61 to 1.24 g/100 g fatty acids, respectively. Changes in milk fatty acid secretion indicated that 28.9% of VA was converted to cis-9, trans-11 CLA. Results provide evidence that conversion by Delta9-desaturase to cis-9, trans-11 CLA in the lactating cow is independent of postruminal VA supply. In conclusion, endogenous synthesis via VA was equivalent to approximately 21% of the response to increases in cis-9, trans-11 CLA available for absorption.  相似文献   
95.
96.
Magnetic resonance imaging of patellofemoral relationships   总被引:2,自引:0,他引:2  
Patellofemoral relationships were analyzed in 11 patients (13 knees) with patellar dislocation and 15 asymptomatic subjects (15 knees) at 0° and 20° of flexion. The measurements were made from five consecutive axial images through the patellofemoral joint. The six indices measured were lateral patellar tilt (LPT), lateral patellofemoral angle (LPA), lateral patellar displacement (LPD), patella-lateral condyle index (L/PW), congruence angle (CA), and sulcus angle (SA). The reproducibility of the method was evaluated. The difference between the two study groups was more evident at 0° than at 20° of knee flexion. Significant differences were noted between measurements made at different levels of the joint, particularly in the controls. Isometric contraction of the quadriceps muscle lateralized and tilted the patella slightly in both groups. L/PW with and without quadriceps muscle contraction, and LPA with reference to the anterior condyles differentiated between the two study groups most clearly. LPT and LPA with reference to the anterior condyles differentiated the study groups better than LPT and LPA with reference to the posterior condyles. The reproducibility was good except for inter-observer comparison of CA and SA. The use of an imaging plane selected at the midpoint of the patellar articular cartilage increases the sensitivity of the measurements, since it takes into account both the height of the patella and the tendency towards lateralization. These results indicate that patellar tilt is best measured with the LPA index and patellar lateralization with the L/PW index at 0° knee flexion. This study should always include isometric contraction of the quadriceps muscle.  相似文献   
97.
Ospemifene is a novel selective estrogen receptor modulator (SERM) that is initially being developed for the treatment of vaginal atrophy in postmenopausal women. However, it also shows promise in the prevention and treatment of osteoporosis. As a part of a phase II trial, we compared the effects of ospemifene and raloxifene on bone turnover in postmenopausal women. The study was conducted as a randomized, double-blind study in which 118 healthy postmenopausal women received 30 (n = 29), 60 (n = 30), or 90 mg (n = 30) ospemifene or 60 mg (n = 29) raloxifene for 3 months. Bone resorption was assessed by measuring the urinary outputs of N- and C-terminal cross-linking telopeptides of type I collagen (NTX and CTX, respectively). Bone formation was assessed by measuring bone-specific alkaline phosphatase (bone ALP), osteocalcin (OC), procollagen type I N propeptide (PINP), and procollagen type I C propeptide (PICP) in serum. All markers were studied before and at 3 months and 2–4 weeks after cessation of the medication. Urine NTX outputs decreased in all study groups, and the only statistically significant difference in NTX was observed between raloxifene and 30 mg ospemifene, which was reduced more in the raloxifene group. The output of CTX decreased most clearly in 60- and 90-mg ospemifene groups, but no significant differences between study groups emerged. A significant difference was found between the 90-mg ospemifene group and raloxifene in PINP in favor of ospemifene. No other differences in bone formation markers emerged between ospemifene and raloxifene. The study confirms the bone-restoring activity of ospemifene, which is comparable to that of raloxifene.  相似文献   
98.
99.
Low-trauma fractures of elderly people are a major public health burden worldwide, and as the number and mean age of older adults in the population continue to increase, the number of fractures is also likely to increase. Epidemiologically, however, an additional concern is that, for unknown reasons, the age-standardized incidence (average individual risk) of fracture has also risen in many populations during the recent decades. Possible reasons for this rise include a birth cohort effect, deterioration in the average bone strength by time, and increased average risk of (serious) falls. Literature provides evidence that the rise is not due to a birth cohort effect, whereas no study shows whether bone fragility has increased during this relatively short period of time. This osteoporosis hypothesis could, however, be tested if researchers would now repeat the population measurements of bone mass and density that were made in the late 1980s and the 1990s. If such studies proved that women's and men's age-standardized mean values of bone mass and density have declined over time, the osteoporosis hypothesis would receive scientific support. The third explanation is based on the hypothesis that the number and/or severity of falls has risen in elderly populations during the recent decades. Although no study has directly tested this hypothesis, a great deal of indirect epidemiologic evidence supports this contention. For example, the age-standardized incidence of fall-induced severe head injuries, bruises and contusions, and joint distortions and dislocations has increased among elderly people similarly to the low-trauma fractures. The fall hypothesis could also be tested in the coming years because the 1990s saw many research teams reporting age- and sex-specific incidences of falling for elderly populations, and the same could be done now to provide data comparing the current incidence rates of falls with the earlier ones.  相似文献   
100.
We have investigated gene amplification of fibroblast growth factor receptor-4 (FGFR4) gene in 30 primary breast tumor samples and 15 gynecological tumor samples. Ten percent of the breast tumors showed 2- to 4-fold amplification. Amplification was found more frequently in estrogen- and progesterone-receptor-positive tumors and in tumors with high lymph-node involvement. Breast tumor samples were also analyzed for the amplification of fgfr3 and erbB2 genes and the chromosome I Iq 13 located genes hst I Iint2lbci1 /sea. erbB2 gene was amplified 2- to 13-fold in 13% of the cases, but no amplification of int2/hst I/be/1/sea amplicon was found. Gynecological tumors were also analyzed for the amplification of fgfr4 and fgfr3 genes and for int2 and hst I oncogenes. Eleven of the 15 gynecological tumors were ovarian neoplasms including 2 benign tumors; the remainder comprised I ovarian metastasis of breast cancer; I endometrial cancer; I uterine leiomyosarcoma and I carcinosarcoma of the fallopian tube. In gynecological tumors, fgfr4 gene was found to be amplified in 2 ovarian tumors. Amplification of hst I was found in I benign ovarian tumor. Thus, the fgfr4 gene may be involved in breast and ovarian tumorigenesis.  相似文献   
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