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1.
PURPOSE: Men have a lower uptake of genetic services than women; however, the specific needs and preferences of men at risk of genetic conditions other than hereditary breast ovarian cancer are not known. We ascertain the information preferences of men with a family history of prostate cancer. METHODS: Unaffected men and their partners were administered a written questionnaire. RESULTS: Responses were received from 280 men (response rate: 59.2%) and 174 partners (response rate: 74%). Most men (59.6%) reported having insufficient information about their risk and wanted further information about personal risk (93.2%) and risk management (93.6%). Strikingly, 56.3% preferred to receive information related only to positive outcomes. Urologists were the preferred source of information, but there was considerable interest in a multidisciplinary service approach significantly associated with the number of affected relatives (odds ratio = 1.94, P < .002). Partners' level of concern was not associated with interest in multidisciplinary services, satisfaction with information, or support received. CONCLUSIONS: Delivering services to men at risk will require a multifaceted approach by primary care providers and specialists. Challenges include meeting men's expectations in the face of uncertain medical knowledge, engaging those at high risk in multidisciplinary services, and delivering tailored information to those at lower risk.  相似文献   
2.
Lipid levels in plasma strongly influence the risk for coronary heart disease. To localise and subsequently identify genes affecting lipid levels, we performed four genome-wide linkage scans followed by combined linkage/association analysis. Genome-scans were performed in 701 dizygotic twin pairs from four samples with data on plasma levels of HDL- and LDL-cholesterol and their major protein constituents, apolipoprotein AI (ApoAI) and Apolipoprotein B (ApoB). To maximise power, the genome scans were analysed simultaneously using a well-established meta-analysis method that was newly applied to linkage analysis. Overall LOD scores were estimated using the means of the sample-specific quantitative trait locus (QTL) effects inversely weighted by the standard errors obtained using an inverse regression method. Possible heterogeneity was accounted for with a random effects model. Suggestive linkage for HDL-C was observed on 8p23.1 and 12q21.2 and for ApoAI on 1q21.3. For LDL-C and ApoB, linkage regions frequently coincided (2p24.1, 2q32.1, 19p13.2 and 19q13.31). Six of the putative QTLs replicated previous findings. After fine mapping, three maximum LOD scores mapped within 1 cM of major candidate genes, namely APOB (LOD=2.1), LDLR (LOD=1.9) and APOE (LOD=1.7). APOB haplotypes explained 27% of the QTL effect observed for LDL-C on 2p24.1 and reduced the LOD-score by 0.82. Accounting for the effect of the LDLR and APOE haplotypes did not change the LOD score close to the LDLR gene but abolished the linkage signal at the APOE gene. In conclusion, application of a new meta-analysis approach maximised the power to detect QTLs for lipid levels and improved the precision of their location estimate.  相似文献   
3.
The results of histological and immunohistochemical examination of gastric and duodenal biopsy specimens from 50 volunteers without a clinical history of gastrointestinal disease are reported. Multiple specimens of tissue from standard sites in the stomach and duodenum were carefully orientated, and serially sectioned for examination by light microscopy and for immunohistochemical characterisation of plasma cells within the lamina propria. The antrum and fundus were normal in 32 of the 50 subjects but the other 18 showed histopathological evidence of gastritis in either the antrum or fundus. The latter appeared to be age-related. There was considerable variation in the appearance of the surface epithelium of the duodenum within as well as among individual subjects. Superficial gastric metaplasia in one or more biopsy specimens from the duodenal bulb was found in 64% of individuals. Histopathological examination of the duodenum revealed signs of chronic inflammation in 12% of the subjects. In two individuals there was active inflammation but in only one of these was the diagnosis made on endoscopic appearances. Histological criteria important for the diagnosis of duodenitis are discussed. The number of plasma cells in different biopsy specimens from subjects not showing histological signs of inflammation was variable. The ratio IgA:IgG:IgM producing plasma cells was remarkably constant from subject to subject as well as from specimen to specimen.  相似文献   
4.
Serum carcinoembryonic antigen concentrations (serum CEA) in 80 patients with primary breast cancer were measured preoperatively, one month after operation, and thereafter serially every third month. These data were related to histological and morphometric features of the primary breast carcinoma and the lymph node metastases and to clinical follow up data. Analysis of the serum CEA values showed significant correlations with size of tumour, the presence of lymph node metastases, oestrogen receptor, and occurrence of distant metastases. Furthermore, the results indicated that serial determination of serum CEA in the first two years after operation may be useful in monitoring for the occurrence of distant metastases in patients with metastatic spread to lymph nodes and with large (greater than or equal to 2 cm) primary breast tumours positive for oestrogen receptor. In agreement with other studies, however, it was found that the predictive value of serum CEA concentrations in general is weak and costs may prohibit the implementation of the routine assessment of CEA concentrations.  相似文献   
5.
Classical evolutionary theory predicts the existence of genes with antagonistic effects on longevity and various components of early-life fitness. Quantitative genetic studies have provided convincing evidence that such genes exist. However, antagonistic pleiotropic effects have rarely been attributed to individual loci. We examine several classes of longevity-assurance genes: those involved in regulation of the gonad; the insulin-like growth factor pathway; free-radical scavenging; heat shock proteins and apoptosis. We find initial evidence that antagonistic pleiotropic effects are pervasive in each of these classes of genes and in various model systems--although most studies lack explicit studies of fitness components. This is particularly true of human studies. Very little is known about the early-life fitness effects of longevity loci. Given the possible medical importance of such effects we urge their future study.  相似文献   
6.
OBJECTIVE: To determine whether population differences can explain the contrasting impacts on HIV observed in the Mwanza trial of sexually transmitted disease (STD) syndromic treatment (ST), the Rakai trial of STD mass treatment (MT), and the Masaka trial of information, education, and communication (IEC) with and without ST as well as to predict the effectiveness of each intervention strategy in each population. METHODS: Stochastic modeling of the transmission of HIV and 6 STDs was used with parameters fitted to demographic, sexual behavior, and epidemiological data from the trials and general review of STD/HIV biology. RESULTS: The baseline trial populations could be simulated by assuming higher risk behavior in Uganda compared with Mwanza in the 1980s, followed by reductions in risk behavior in Uganda preceding the trials. In line with trial observations, the projected HIV impacts were larger for the ST intervention in Mwanza than for the MT intervention in Rakai or the IEC and IEC + ST interventions in Masaka. All 4 simulated intervention strategies were more effective in reducing incidence of HIV infection in Mwanza than in either Rakai or Masaka. CONCLUSIONS: Population differences in sexual behavior, curable STD rates, and HIV epidemic stage can explain most of the contrast in HIV impact observed between the 3 trials. This study supports the hypothesis that STD management is an effective HIV prevention strategy in populations with a high prevalence of curable STDs, particularly in an early HIV epidemic.  相似文献   
7.
Parietal cell protrusion (PCP), swelling and bulging of parietal cells, has been observed in the oxyntic mucosa of patients receiving omeprazole. The frequency of this event and the underlying mechanisms remain to be clarified. As such, it is unknown whether there is a relation with either serum gastrin or Helicobacter pylori infection, and whether PCP predisposes to the development of fundic gland cysts (FGC). We therefore investigated the development of PCP and FGC in gastroesophageal reflux disease (GERD) patients treated with omeprazole and correlated findings to duration of therapy, gastrin, and H pylori infection. In a randomized, double-blinded study, GERD patients were evaluated by endoscopy with biopsy sampling for histology and culture at baseline, and after 3 and 12 months' therapy with omeprazole 40 mg daily. H pylori-positive patients were randomized to additional eradication therapy or placebo antibiotics at baseline. All histological slides were scored blinded for time and outcome of culture for the presence of PCP and FGC. Fasting serum samples from all visits were used for gastrin measurements. The prevalence of PCP increased during omeprazole therapy from 18% at baseline to 79% and 86% at 3 and 12 months (P < .001, baseline v both 3 and 12 months). The prevalence of FGC increased from 8% to 17% and 35% (P < .05, baseline v 12 months). The prevalence of PCP and FGC did not differ among the H pylori-positive and H pylori-negative patients at baseline (PCP 16% v 20% and FGC 7% v 8%, respectively). Whereas H pylori eradication did not significantly affect development of PCP (P = .7), FGC developed significantly more often in the H pylori-eradicated patients when compared with persistent H pylori-positive patients (P < .05). PCP development was related to serum gastrin rise during therapy. In conclusion, PCP occurs in most patients within the first months of omeprazole treatment and is related to increased gastrin levels. FGC develops more gradually and is enhanced by H pylori eradication.  相似文献   
8.
beta(2)-Glycoprotein I (beta(2)GPI) is a principal target antigen for antiphospholipid antibodies associated with recurrent pregnancy loss and fetal growth restriction in women. The significance of disrupted beta(2)GPI activity in contributing to pregnancy pathology in antiphospholipid syndrome (APS) is not clear. In this study the physiological requirement for functional beta(2)GPI in pregnancy was investigated by evaluating reproductive outcomes in beta(2)GPI null mutant (beta(2)GPI-/-) mice. beta(2)GPI-/- mice were fertile and carried viable fetuses to term. However, there was an 18% reduction in the number of viable implantation sites in beta(2)GPI-/- mice and reduced fetal weight and fetal:placental weight ratio in late gestation, suggesting compromised placental function. Placental architecture was altered in beta(2)GPI-/- implantation sites with a 24% increase in the junctional zone: labyrinthine ratio, but placentae showed no evidence of increased thrombosis in the absence of beta(2)GPI. The effect of beta(2)GPI genotype on pregnancy success after passive transfer of human and mouse antibodies reactive with beta(2)GPI was also explored. Two of five anti-beta(2)GPI antibodies induced pregnancy loss in beta(2)GPI+/+ mice but beta(2)GPI-/- mice were refractory to antibody-induced pregnancy failure. We conclude that functional beta(2)GPI is not essential for successful pregnancy in mice, but optimal placental development and fetal growth require this molecule. Together these data are consistent with pathogenic mechanisms in antiphospholipid syndrome involving both neutralization of beta(2)GPI function and beta(2)GPI-immunoglobulin complex formation.  相似文献   
9.
Vascular smooth muscle cells of rabbit aorta were enzymatically dispersed, kept in primary culture, and studied between days 1 and 7 in a bath rinsed with Ringer-like solution at 37°C. The electrical membrane potential difference (PD) was measured with microelectrodes. The mean value of PD was –50±0.4 mV (n=53). Cromakalim (BRL 34915), 1 mol/l and 10 mol/l, hyperpolarized the membrane potential by 9±1 mV (n=11) and 15±1 mV (n=53) respectively. Glibenclamide (10 mol/l) abolished the hyperpolarizing effect of cromakalim (n=6). Simultaneous addition of cromakalim and glibenclamide (both 10 mol/l, n=11) and glibenclamide itself (10 mol/l, n=7) had no effect on PD. In patch-clamp experiments in outside-out-oriented Ca2+-sensitive K+ channels, cromakalim increased the open probability (P o) only slightly and only with a cytosolic Ca2+ activity of 1 mol/l. In all other series cromakalim had no effect on the P o of these channels. Forskolin (10 mol/l) hyperpolarized PD by 6±1 mV (n=13). The nucleotides UTP, ATP and ITP (10 mol/l) depolarized PD by 12±1 mV (n=7), 8±1 mV (n=65) and 5±1 mV (n=6) respectively. GTP, [,-methylene]ATP and adenosine had no significant effect. Mn2+ (1 mmol/l, n=18), Ni2+ (1 mmol/l, n=13), Co2+ (1 mmol/l, n=11), Zn2+ (1 mmol/l, n=6) and the Ca2+-channel blockers verapamil and nifedipine (both 0.1 mmol/l, n=6) did not attenuate the depolarization induced by 10 mol/l ATP. Fetal calf serum (100 ml/l, n=7) depolarized PD by 11±2 mV. This effect was not abolished by nifedipine or by replacing NaCl by choline chloride. The data indicate that PD of vascular smooth muscle cells is depolarized by P2 agonists and hyperpolarized by the K+-channel opener cromakalim. The effect of cromakalim is antagonized by glibenclamide. The effect of cromakalim is probably not mediated by the K+ channel identified in excised patches.Supported by DFG Gr 480/10  相似文献   
10.
The X-ray structural investigation of the naphthoylenebis-(benzimidazole) ( 1 ) cis- and trans-isomers as models for the cis and trans elementary units of the corresponding poly(naphthoylene-benzimidazoles) (PNBI) was carried out. The correctness of the previous identification of the isomers was confirmed, and exact geometrical parameters of the PNBI elementary units (required, in particular, for the calculation of the Kuhn segment of PNBI) were determined. Quantum-chemical semi-empirical calculations of the ground and excited electronic states of the isomers were carried out. Both experimental and theoretical data confirm a larger stability of the planar π-conjugated structure of the trans-isomer in comparison with the cis-isomer in the ground as well as in the excited electronic state. Crystals of the cis- and trans-isomers obtained from trifluoroacetic acid solutions are the solvates of bis(trifluoroacetates) of diprotonated 1 with an extremely high content of the solvating trifluoroacetic acid. This peculiarity is favourable for modelling the main characteristics of the interaction between PNBI and protonic polar solvent molecules, viz. preferred types of H-bonding and a possibility of interaction of the electronic lone pairs of the solvent molecules with the π-electronic systems of the elementary units of PNBI by charge transfer complexes.  相似文献   
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