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81.
82.
ObjectiveThe aim of this study was to compare the neonatal umbilical artery blood gas values, C-reactive protein (CRP) levels, nucleated red blood cells (NRBCs), and white blood cells (WBCs) differential counts between offspring’s of the diabetic mothers who needed insulin during pregnancy and normal mothers after cesarean delivery.Materials and MethodsA prospective study was performed involving 68 pregnant diabetic women who needed insulin during pregnancy and 410 healthy pregnant women and their neonates with gestational ages between 35 weeks and 41 weeks. Arterial blood was analyzed for pH and blood gas values and venous blood was analyzed for CRP level, NRBC, and WBC differential counts.ResultsThe mean NRBC count in the neonates of diabetic mothers and healthy mothers was 560 ± 985/μL and 202 ± 281/μL, respectively (p < 0.001). The umbilical arterial blood gas showed a lower pH (7.22 ± 0.07 vs. 7.24 ± 0.04, p = 0.004) and a higher pCO2 (49.33 ± 10.08 vs. 47 ± 8.67, p = 0.045) in neonates of diabetic mothers compared with the controls. Values of pO2, HCO3?, base excess, WBC differential counts, and CRP levels were almost similar in the two groups.ConclusionLower pH, higher pCO2, and elevated NRBC counts were found in the neonates of diabetic mothers that may be suggestive of chronic intrauterine acidosis.  相似文献   
83.
促红细胞生成素对实验性肾性贫血的作用   总被引:1,自引:0,他引:1  
促红细胞生成素(erythropoietin,EPO)是由肾细胞分泌的一种糖蛋白激素。从人胚肾细胞中诱导,经生物化学方法分离、提纯得到此品。本试验用5/6肾切除的方法造成大鼠慢性肾衰性(CRF)贫血,研究不同剂量EPO对CRF贫血的作用。结果表明EPO有显著的促进红细胞生成,改善CRF贫血状态,使其接近或达到正常水平,最佳剂量为1000 U/kg,并可预防实验性贫血,对正常鼠未见明显作用。  相似文献   
84.
The present study compared sign-only to simultaneous sign and speech (SIMCOM) on recall of stories by deaf children. Thirty-six 11 to 14-year-old deaf students were presented with a series of short stories “bimodally” (using simultaneous sign and speech/SIMCOM) and “unimodally” (using sign-only) and then asked to recall whatever they could remember. A within-subject analysis was used to examine the differences in recall scores as a function of communication mode. Participants scored significantly higher in the sign-only condition than in the SIMCOM condition. There were no differences due to age, gender, home language, pure-tone average, or type of hearing-assistive technology (hearing aids or cochlear implants), but scores in both groups correlated with standardized reading scores. The finding of improved recall with sign-only presentation suggests that simultaneous speech and sign may have compromised comprehension by competing for limited attentional resources. The findings challenge the use of SIMCOM in classrooms.  相似文献   
85.
BACKGROUND & AIMS: After partial hepatectomy, liver regeneration occurs with the return of hepatocyte mass to normal, Limited data exist regarding the renewal of the biliary tree after partial hepatectomy. This study tested the hypothesis that, after partial hepatectomy, the biliary tree regenerates by proliferation of the remaining cholangiocytes, leading to an increase in secretin-induced ductal bile secretion. METHODS: After 70% partial hepatectomy, cholangiocyte proliferation was assessed in situ by morphometric analysis and In vitro by measurement of 3H-thymidine incorporation. Ductal secretion was estimated by measurement of secretin receptor gene expression and adenosine 3',5'-cyclic monophosphate (cAMP) levels in vitro and by the effect of secretin on ductal bile secretion in vivo. RESULTS: DNA synthesis was undetectable in control cholangiocytes, increased and peaked at day 3 after partial hepatectomy, and returned to normal by day 28. Morphometric analysis showed regrowth of the biliary tree beginning at day 1 with restoration by day 10. The expression of secretin receptor gene and secretin-induced cAMP levels and secretin- induced bicarbonate-rich choleresis increased during the period of bile duct renewal. CONCLUSIONS: After partial hepatectomy, the increase in secretin-induced ductal bile secretion observed during bile duct renewal results from proliferation of remaining cholangiocytes. (Gastroenterology 1996 Dec;111(6):1633-44)  相似文献   
86.

Background:

The quality of liver biopsy specimens obtained with different fine needle biopsy (FNB) techniques has not been compared.

Objectives:

This study was performed to evaluate the diagnostic quality of three different liver FNB biopsy techniques.

Materials and Methods:

Two sequential biopsy series were performed on piglets. Three biopsy techniques were compared: capillary-FNB, core-FNB (CFNB) and vacuum-assisted CFNB (VACFNB) in a swine model. Initially, 30 liver biopsies were performed (ten for each technique). The cellularity and quantity of blood in specimens were measured and compared. In the second series, 54 additional biopsies using CFNB and VACFNB techniques (27 each) in a separate piglet were evaluated in the same fashion.

Results:

In the first series, cellularity and blood levels were significantly lower in capillary-FNB compared with CFNB (P < 0.001 and P = 0.011, respectively). There was no significant difference between CFNB and VACFNB in cellularity and blood (P = 0.15 and P = 0.1, respectively). In the second series, cellularity was significantly higher in CFNB compared with VACFNB (P < 0.001) with no significant difference in blood (P = 0.5).

Conclusions:

Among these three different FNB techniques, CFNB technique provided the greatest cellularity. Capillary-FNB technique was inferior among all with the lowest quality of obtained material for cytopathological interpretation.  相似文献   
87.
To determine whether reactive oxygen molecules could directly and reversibly increase the transfer of albumin across an endothelial barrier, we measured albumin transfer across monolayers of endothelium cultured on micropore filters before and after exposure to xanthine and xanthine oxidase. Xanthine and xanthine oxidase increased endothelial albumin transfer in a dose-dependent fashion. Parallel phase contrast and fluorescence microscopy demonstrated retraction of adjacent cells from one another and disruption of the actin filaments. The oxidant- induced increases in albumin transfer and changes in cell shape were reversed by removing xanthine oxidase and then incubating the monolayers for 3 1/2 hours in tissue culture media enriched with fetal bovine serum. However, incubation in tissue culture media without serum resulted in progressive injury and cell death. Hence, the brief exposure to oxidants initiated a progressive injury process that was reversed by incubation in serum. Because intracellular and extracellular calcium are important determinants of cell shape, and because some oxidized membrane lipids act as calcium ionophores, we asked whether oxidants altered endothelial calcium homeostasis. Xanthine-xanthine oxidase increased release of 45Ca++ from preloaded cells. The calcium antagonist lanthanum chloride prevented xanthine- xanthine oxidase increases in endothelial albumin transfer and prevented the changes in cell shape; chelation of extracellular calcium inhibited lysis of endothelium by xanthine-xanthine oxidase; and the calcium ionophore A23187 increased endothelial albumin transfer and mimicked the oxidant-induced changes in cell shape. Lanthanum chloride inhibited these effects of A23187. These data suggest that oxygen radicals can reversibly increase endothelial permeability to macromolecules, that this is associated with reversible changes in endothelial cell shape and actin filaments, and that the changes in cell shape are related to oxidant-induced changes in endothelial calcium homeostasis.  相似文献   
88.
Patterns of cell proliferation and cell migration in the Sezary syndrome   总被引:1,自引:0,他引:1  
Bunn  PA Jr; Edelson  R; Ford  SS; Shackney  SE 《Blood》1981,57(3):452-463
The patterns of cell proliferation and cell migration were studied in three patients with the Sezary syndrome using autoradiographic techniques. Cell labeling patterns following pulse labeling with tritiated thymidine in vivo indicated that Sezary cells proliferate actively in skin and in lymph nodes but that few if any Sezary cells proliferate in the peripheral blood. In two of the patients serial samples were obtained. Label dilution patterns in skin and blood over time suggested that circulating Sezary cells originated in extracutaneous sites where cells were proliferating more rapidly than in the skin. Cells labeled in extracutaneous sites of proliferation appear rapidly in the blood, and their transit time through the peripheral blood compartment is short. Circulating Sezary cells may then be deposited in the skin where they resume proliferation at a low rate. Thus, while Sezary cells proliferate in both cutaneous and extracutaneous sites, proliferation appears to be more rapid in extracutaneous sites such as lymph nodes. This suggests that trials of systemic therapeutic approaches should be undertaken.  相似文献   
89.
Bone marrow from animals treated with 5-fluorouracil (5FU) competes equally with normal marrow when assessed in vivo in an irradiated mouse, but shows markedly defective engraftment when transplanted into noncytoablated hosts. Using Southern Blot analysis and a Y-chromosome specific probe, we determined the level of engraftment of male donor cells in the bone marrow, spleen, and thymus of unprepared female hosts. We have confirmed the defective engraftment of marrow harvested 6 days after 5FU (FU-6) and transplanted into unprepared hosts and shown that this defect is transient; by 35 days after 5FU (FU-35), engraftment has returned to levels seen with normal marrow. FU-6 marrow represents an actively cycling population of stem cells, and we hypothesize that the cycle status of the stem cell may relate to its capacity to engraft in the nonirradiated host. Accordingly, we have evaluated the cycle status of engrafting normal and FU-6 marrow into normal hosts using an in vivo hydroxyurea technique. We have shown that those cells engrafting from normal marrow and over 70% of the cells engrafting from FU-6 marrow were quiescent, demonstrating no killing with hydroxyurea. We have also used fluorescent in situ hybridization (FISH) analysis with a Y-chromosome probe and demonstrated that normal and post-5FU engraftment patterns in peripheral blood were similar to those seen in bone marrow, spleen, and thymus. Altogether these data indicate that cells engrafting in normal, unprepared hosts are dormant, and the defect that occurs after 5FU is concomitant with the induction of these cells to transit the cell cycle.  相似文献   
90.
Delfino  DV; Patrene  KD; Lu  J; Deleo  A; Deleo  R; Herberman  RB; Boggs  SS 《Blood》1996,87(6):2394-2400
Natural killer (NK) cells develop from the nonadherent cell component of NK long-term bone marrow (BM) cultures (NK-LTBMC). Because these nonadherent cells are depleted of mature NK cells and T cells, but appear to enriched for NK precursors, they were used as a starting population to begin to define the NK precursors that function in NK- LTBMC. As the stromal cell component of NK-LTBMC has been shown to support interleukin (IL)-2-induced, CD44 dependent, NK cell development from nonadherent NK precursors, NK-LTBMC stroma was used in a limiting dilution assay (LDA) to quantitate the precursors. NK-LTBMC in 96-well plates were irradiated (20 Gy) to kill hematopoietic cells (including the NK precursors), seeded with limiting dilutions of the cells to be quantitated, cultured with 500 U/mL IL-2 for 13 days and assayed for development of NK activity by adding 51Cr-labeled YAC-1 cells to the wells and evaluating the release of 51Cr after 4 hours. Flow cytometric analysis, sorting, and quantitation of the nonadherent cell component of NK-LTBMC showed that NK precursors were concentrated in the CD44neg/dim subset that comprised 10% of the "lymphoid" gated cells. When the CD44neg/dim subset was sorted from BM of mice treated with 5- fluorouracil (5-FU) day before (-1FUBM), there were about 30% T cells, but no NK-1.1+ cells. When the T cells were removed by sorting and the CD44neg/dim, alphabeta, gammadelta T-cell receptorneg (TCR-) subpopulation was seeded onto irradiated stroma with IL-2, they proliferated, developed NK activity, became NK-1.1+ and CD44bright and remained alphabeta, gammadelta TCR-. The frequency of NK precursors in this population as estimated from the LDA was about 1/500.  相似文献   
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