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41.
Eight laboratories in six countries cooperated to clarify several issues concerning the phenotypes of heterozygous carriers of hemophilia "A." Plasma levels of factor VIII (F.VIII:C, formerly VIII:C) and von Willebrand factor (VWF:Ag, formerly VIIIR:Ag) of carriers and normal women were determined by various "in-house" methods; a single lyophilized plasma standard was used for all assays. Analysis of the collated data from 336 carriers (296 obligatory carriers and 40 sporadic carriers) and 137 normal women showed that there was no difference in the F.VIII:C levels of "paternal" carriers (women who had obtained the abnormal gene from their fathers) and "maternal" carriers. Neither was there a difference in the VWF:Ag levels of normal women and either type of carrier. Age was found to have a significant effect on both F.VIII:C and VWF:Ag, values being higher at very young and very old ages, the minima occurring in the 25- to 30-year range. ABO blood type had a striking effect. Women of types A, B, and AB (designated non- O in the study), both normals and carriers, had significantly higher levels of both factors than did women of type O. Analysis by laboratories showed that differences in mean levels of both factors between laboratories were highly significant. It was concluded that age, ABO blood type, and laboratory variation should be taken into account in carrier detection.  相似文献   
42.
43.
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states.  相似文献   
44.
Parainfluenza virus 3 (PIV-3) is a common viral infection not only in humans, but also in many other species. Serological evidence suggests that nearly 100 % of children in the United States have been infected with PIV-3 by 5 years of age. Similarly, in cattle, PIV-3 is commonly associated with bovine respiratory disease complex. A novel dolphin PIV-3 (TtPIV-1) was described by Nollens et al. in 2008 from a dolphin that was diagnosed with an unknown respiratory illness. At that time, TtPIV-1 was found to be most similar to, but distinct from, bovine PIV-3 (BPIV-3). In the present study, similar viral growth kinetics and pro-inflammatory cytokine (IL-1β, IL-6, and CXCL8) production were seen between BPIV-3 and TtPIV-1 in BEAS-2B, MDBK, and Vero cell lines. Initial nomenclature of TtPIV-1 was based on partial sequence of the fusion and RNA polymerase genes. Based on the similarities we saw with the in vitro work, it was important to examine the TtPIV-1 genome in more detail. Full genome sequencing and subsequent phylogenetic analysis revealed that all six viral genes of TtPIV-1 clustered within the recently described BPIV-3 genotype B strains, and it is proposed that TtPIV-1 be re-classified with BPIV-3 genotype B strains.  相似文献   
45.
Shami  PJ; Weinberg  JB 《Blood》1996,87(3):977-982
Nitric oxide (NO) is a reactive molecule with numerous physiologic and pathophysiologic roles affecting the nervous, cardiovascular, and immune systems. In previous work, we have demonstrated that NO inhibits the growth and induces the monocytic differentiation of cells of the HL- 60 cell line. We have also demonstrated that NO inhibits the growth of acute nonlymphocytic leukemia cells freshly isolated from untreated patients and increases monocytic differentiation antigens in some. In the present work, we studied the effect of NO on the growth and differentiation of normal human bone marrow cells in vitro. Mononuclear cells isolated from human bone marrow were cultured in semisolid media and treated with the NO-donating agents sodium nitroprusside (SNP) or S- nitroso-acetyl penicillamine (SNAP) (0.25 to 1 mmol/L). Both agents decreased colony-forming unit-erythroid (CFU-E) and colony-forming unit- granulocyte macrophage (CFU-GM) formation by 34% to 100%. When CD34+ cells were examined, we noted that these cells responded to SNP and SNAP differently than did the mononuclear cells. At a concentration range of 0.25 to 1 mmol/L, SNP inhibited the growth of CFU-E by 30% to 75%. However, at the same concentration range, SNP increased the number of CFU-GM by up to 94%. At concentrations of 0.25 to 1 mmol/L, SNAP inhibited the growth of CFU-E by 33% to 100%. At a concentration of 0.25 mmol/L, SNAP did not affect CFU-GM. At higher concentrations, SNAP inhibited the growth of CFU-GM. Although SNP increased intracellular levels of cGMP in bone marrow cells, increasing cGMP in cells by addition of 8-Br-cGMP (a membrane permeable cGMP analogue) did not reproduce the observed NO effects on bone marrow colonies. These results demonstrate that NO can influence the growth and differentiation of normal human bone marrow cells. NO (generated in the bone marrow microenvironment) may play an important role modulating the growth and differentiation of bone marrow cells in vivo.  相似文献   
46.
The endoplasmic reticulum (ER) lies at the crossroads of protein folding, calcium storage, lipid metabolism, and the regulation of autophagy and apoptosis. Accordingly, dysregulation of ER homeostasis leads to β-cell dysfunction in type 1 and type 2 diabetes that ultimately culminates in cell death. The ER is therefore an emerging target for understanding the mechanisms of diabetes mellitus that captures the complex etiologies of this multifactorial class of metabolic disorders. Our strategy for developing ER-targeted diagnostics and therapeutics is to focus on monogenic forms of diabetes related to ER dysregulation in an effort to understand the exact contribution of ER stress to β-cell death. In this manner, we can develop personalized genetic medicine for ERstress-related diabetic disorders, such as Wolfram syndrome. In this article, we describe the phenotypes and molecular pathogenesis of ERstress-related monogenic forms of diabetes.  相似文献   
47.
The effects of 2 different dietary fats (40% of calories from corn oil or coconut oil), in the presence of high-dietary cholesterol (1.7 mg/kcal), on the lipoprotein profiles of baboons (Papio cynocephalus sp) were studied by analytic ultracentrifugation, gradient gel electrophoresis (GGE), and heparin-manganese chloride precipitation. Relative to the corn oil (polyunsaturated fat) diet, the coconut oil (saturated fat) diet significantly increased total serum cholesterol by 43% (P less than 0.001) by increasing non-precipitable cholesterol (HDL-C) 58% (P less than 0.001) and precipitable cholesterol (VLDL + LDL-C) 35% (P less than 0.001). Analytic ultracentrifugal observations indicated that the increase in HDL-C was due to considerable increases in both HDL-I (baboon HDL of size 100-125 A and hydrated density 1.063-1.120 g/ml) and F1.20 degrees 9-28 lipoproteins (material of size 125-220 A and hydrated density 1.03-1.08 g/ml, and containing HDL apolipoproteins and apo E). Concentrations of other HDL subpopulations were unaffected by the dietary saturated rat. The increase in VLDL + LDL-C was due to increased LDL (S degree F 5-12 lipoproteins) and, to some extent, F1.20 degrees 9-28 lipoproteins because the larger, faster floating subspecies of the F1.20 degrees 9-28 lipoproteins were precipitable by heparin-manganese. In contrast, saturated fat (relative to polyunsaturated fat) induced lower concentrations of IDL (SF degree 12-20) and VLDL (SF degree 20-100). Lipoprotein size distributions by GGE indicated 5 HDL subpopulations and 2 or more LDL subpopulations in the sera of most baboons. The type of dietary fat did not affect the particle size range of each of the the HDL or LDL subpopulations. The results indicate that dietary fat markedly modulates the distribution of cholesterol between apo A-I-containing (HDL and F1.20 degrees 9-28) and apo B-containing (IDL and VLDL) lipoproteins without altering the presence of subpopulations based on particle size.  相似文献   
48.
INTRODUCTION: Diabetes is the leading cause of lower limb amputation in Australia. However, due to limited resources, it is not feasible for everyone with diabetes to access podiatry care, and some objective guidelines of who should receive podiatry is required. METHODS: A total of 250 patients with neuropathy (Biothesiometer; Biomedical Instruments, Newbury, Ohio, USA) ( > 30, age < 65)) but no active foot lesion, and 222 without neuropathy matched for age, type of diabetes, gender and duration, was followed prospectively for 2 years. Sensation was also tested using a 10 g Semmes Weinstein monofilament (Royal Prince Alfred Hospital Diabetes Centre). After the baseline examination, patients were contacted at 6 months and thereafter yearly to determine ulcer status. Incidence of foot ulceration across different risk categories was calculated using Kaplan-Meier survival curve. Log-rank test and Cox's proportional model were used to compare groups. The Number Needed to Treat (NNT) to prevent one ulcer per year was calculated using the standard formulae. RESULTS: During the follow-up period, 34 new ulcers occurred in the neuropathy group and three ulcers in the control group (chi2 (1df) = 21.3; P < 0.0001), equating to an annual incidence of 6.3% and 0.5%, respectively. Fifty-four per cent of the ulcers were due to trauma from footwear. Further stratification of the neuropathy group showed annual incidence of ulceration to be 4% for those with abnormal biothesiometer reading, but who could still feel the monofilament, 10% for those who cannot feel the monofilament and 26% for those with previous ulceration or amputation. Predictors of ulceration were past history of ulceration/amputation (chi2 = 27.8; P < 0.0001) and the presence of neuropathy (chi2 = 4.7; P = 0.03). Assuming a 55% relative risk reduction in ulceration from podiatry care (mean of estimates from 10 reports), the NNT to prevent one foot ulcer per year was: no neuropathy (vibration perception threshold (VPT) < 30)), NNT = 367; neuropathy (VPT > 30) alone, NNT = 45; +cannot feel monofilament, NNT = 18; +previous ulcer/amputation, NNT = 7. CONCLUSION: Provision of podiatry care to diabetic patients should not be only economically based, but should also be directed to those with reduced sensation, especially where there is a previous history of ulceration or amputation.  相似文献   
49.
The host foreign body response (FBR) adversely effects the performance of numerous implanted biomaterials especially biosensors, including clinically popular glucose-monitoring sensors. Reactive formation of a fibrous capsule around implanted sensors hinders the transport of essential analytes to the sensor from the surrounding tissue, resulting in loss of glucose response sensitivity and eventual sensor failure. Several strategies have sought to mitigate the foreign body response's effects on CGM sensors through the use of local delivery of pharmaceuticals and biomolecules with limited success. This study describes release of a tyrosine kinase inhibitor – masitinib – from the sensor implant to target tissue resident mast cells as key mediators of the FBR. Model implants are coated with a composite polymer hydrophilic matrix that rapidly dissolves upon tissue implantation to deposit slower-degrading polymer microparticles containing masitinib. Matrix dissolution limits coating interference with sensor function while establishing a local controlled-release delivery depot formulation to alter implant tissue pharmacology and addressing the FBR. Drug efficacy was evaluated in a murine subcutaneous pocket implant model. Drug release extends to more than 30 days in vitro. The resulting FBR in vivo, evaluated by implant capsule thickness and inflammatory cell densities at 14, 21, and 28 days, displays statistically significant reduction in capsule thickness around masitinib-releasing implant sites compared to control implant sites.  相似文献   
50.
Ceruloplasmin (CP) is a copper-binding protein in vertebrate plasma. It is the product of an intragenic triplication and is composed of three homologous domains. Oligonucleotide probes constructed according to published amino acid sequences were used to identify cDNA clones encoding human CP. Two clones, CP-1 and CP-2, differed from each other by the presence or absence, respectively, of a deduced sequence of four amino acids. The two clones provided 81% of the sequence encoding CP. Comparison of the nucleotides of the three domains of the CP coding sequence revealed internal domain homology with identity of sequences ranging from 50.1% to 56%. The nucleotide sequence of CP-2 cDNa was compared to that of a homologous human protein, clotting factor VIII, and was found to be 48% identical overall. The CP gene was mapped to human chromosome 3 by somatic-cell-hybrid analysis and to 3q25 by in situ hybridization; however, sites of hybridization to DNA on other chromosomal sites suggested additional CP-like DNA sequences in the human genome. A DNA polymorphism was detected with CP cDNA after endonuclease digestion of human DNA by Pst I. CP mRNA was detected in human liver, macrophages, and lymphocytes by in situ histohybridization.  相似文献   
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