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21.
Hypertension and hypercholesterolemia are frequently associated, and their treatment is proven to reduce cardiovascular risk. Current guidelines on cardiovascular prevention strongly recommend treating both disorders. Unfortunately, the low treatment and control rates, combined with the high prevalence of both conditions, still contribute to the high burden of cardiovascular disease in Western countries. In the past 5 years, many studies evaluating the benefit of combined antihypertensive and lipid-lowering treatment on endothelial dysfunction, coronary atherosclerosis, hypertension control, and on primary and secondary prevention of cardiovascular events have been published. In this article, we discuss and critically evaluate the available evidence on the potential benefits of combined antihypertensive and lipid-lowering treatment.  相似文献   
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Isolated mitochondrial complex IV (cytochrome c oxidase) deficiency is an important cause of mitochondrial disease in children and adults. It is genetically heterogeneous, given that both mtDNA-encoded and nuclear-encoded gene products contribute to structural components and assembly factors. Pathogenic variants within these proteins are associated with clinical variability ranging from isolated organ involvement to multisystem disease presentations. Defects in more than 10 complex IV assembly factors have been described including a recent Lebanese founder mutation in PET100 in patients presenting with Leigh syndrome. We report the clinical and molecular investigation of a patient with a fatal, neonatal-onset isolated complex IV deficiency associated with multiorgan involvement born to consanguineous, first-cousin British Asian parents. Exome sequencing revealed a homozygous truncating variant (c.142C>T, p.(Gln48*)) in the PET100 gene that results in a complete loss of enzyme activity and assembly of the holocomplex. Our report confirms PET100 mutation as an important cause of isolated complex IV deficiency outside of the Lebanese population, extending the phenotypic spectrum associated with abnormalities within this gene.  相似文献   
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Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.  相似文献   
24.
Independent predictors of isolated clinic ('white-coat') hypertension   总被引:3,自引:0,他引:3  
BACKGROUND: Hypertension guidelines recommend 24 h ambulatory blood pressure (ABP) monitoring in hypertensive subjects with suspected isolated clinic hypertension (ICH). However, the pre-test probability of ICH based on the distribution of its independent predictors has not yet been estimated in hypertensive subjects with mildly elevated blood pressure. OBJECTIVE: To ascertain the independent predictors of ICH in mildly hypertensive subjects. METHODS: In the setting of the HARVEST-PIUMA collaboration, we studied 1564 subjects with hypertension stage I. At entry, all subjects were untreated and all underwent ABP monitoring and echocardiography. Diabetes, hypertension grade > I, renal failure or previous cardiovascular morbid events were exclusion criteria. Clinic BP was 143/92 mmHg (SD 9/5) and 24 h ABP was 128/81 mmHg (SD 10/8). RESULTS: Prevalence of ICH (daytime ABP < 130 mmHg systolic and 80 mmHg diastolic) was 10.4%. In a multivariate logistic regression analysis, sex (P = 0.002), smoking (P = 0.038) and clinic diastolic BP (P = 0.0002) were the sole independent predictors of ICH according to the following equation: Y = 2.6438 + 0.5128 x sex (0 = men; 1 = women) + 0.4543 x current smoking (0 = yes; 1 = no) - 0.0531 x clinic diastolic BP (mmHg) and P (probability of ICH) = exp(Y)/[1 + (exp(Y)]. Left ventricular (LV) mass at echocardiography was a further independent predictor (P = 0.002) of ICH according to the following equation: Y= 3.4343 + 0.4603 x sex + 0.5989 x current smoking - 0.0482 x clinic diastolic BP - 0.0312 x LV mass [g/height (m)2.7]. LV mass was greater (P < 0.01) in the group with ambulatory hypertension [42.3 g/height (m)2.7] than in that with ICH [39.2 g/height (m)2.7] and not dissimilar between the ICH group and a control group of 370 healthy normotensive subjects [38.1 g/height (m)2.7]. CONCLUSIONS: In untreated subjects with stage I hypertension, ICH is most frequent among women, nonsmokers and subjects with low clinic BP and smaller LV mass. These findings allow identification of subjects with indication to ABP monitoring because of suspected ICH.  相似文献   
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Okamoto  S; Olson  AC; Berdel  WE; Vogler  WR 《Blood》1988,72(5):1777-1783
Ether lipids (EL) and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemic cells. In this study, the combined effects of EL (ET-18-OCH3, ET-16-NHCOCH3, or BM 41.440) and hyperthermia on the growth of hematopoietic progenitors, myeloid leukemic cell lines, and leukemic cells obtained from patients with acute myeloid leukemia (AML) were examined to determine if this combination resulted in a greater selective killing of leukemic cells than that achieved by either EL or heat alone. When the cells were treated simultaneously with EL (50 micrograms/mL) and hyperthermia (42 degrees C) for one hour, the killing of leukemic cell line cells was enhanced considerably. Among the three EL, however, the combination of ET-18-OCH3 and heat seemed to be the most cytotoxic to leukemic cell line cells with no effect on the growth of hematopoietic progenitors. An increase in the duration of treatment with ET-18-OCH3 to four hours with heat added during the last hour resulted in a further reduction of leukemic cell line cells while sparing 50% of hematopoietic progenitors after cryopreservation. The combined treatment with ET-18-OCH3 and heat also inhibited the growth of leukemic progenitors obtained from AML patients by 97% to 100%. These data indicate that the combined treatment with EL and hyperthermia might offer an efficient means to eliminate myeloid leukemic cells in vitro.  相似文献   
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It is unclear whether revascularization of renal artery stenosis (RAS) by means of percutaneous renal angioplasty and stenting (PTRAS) is advantageous over optimal medical therapy. Hence, we designed a randomized clinical trial based on an optimized patient selection strategy and hard experimental endpoints. Primary objective of this study is to determine whether PTRAS is superior or equivalent to optimal medical treatment for preserving glomerular filtration rate (GFR) in the ischemic kidney as assessed by 99mTcDTPA sequential renal scintiscan. Secondary objectives of this study are to establish whether the two treatments are equivalent in lowering blood pressure, preserving overall renal function and regressing target organ damage, preventing cardiovascular events and improving quality of life. The study is designed as a prospective multicentre randomized, un-blinded two-arm study. Eligible patients will have clinical and angio-CT evidence of RAS. Inclusion criteria is RAS affecting the main renal artery or its major branches either >70% or, if <70, with post-stenotic dilatation. Renal function will be assessed with 99mTc-DTPA renal scintigraphy. Patients will be randomized to either arms considering both resistance index value in the ischemic kidney and the presence of unilateral/bilateral stenosis. Primary experimental endpoint will be the GFR of the ischemic kidney, assessed as quantitative variable by 99TcDTPA, and the loss of ischemic kidney defined as a categorical variable.  相似文献   
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