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31.
Snipes  RG; Lam  KW; Dodd  RC; Gray  TK; Cohen  MS 《Blood》1986,67(3):729-734
Tartrate-resistant acid phosphatase (TRAcP) is used as a marker for osteoclasts, which are believed to be derived from phagocytic cells or phagocyte stem cell precursors. To further investigate the relationship between monocytic phagocytes and osteoclasts, acid phosphatase (AcP) activity was measured by three different techniques in human peripheral blood monocytes, monocyte-derived macrophages, and the U937 cell line. We found that cytochemistry and gel electrophoresis led to similar results, but that the colorimetric assay was inconsistent. Normal human peripheral monocytes expressed both tartrate-sensitive and -resistant AcP. In culture these cells formed polykaryons and expressed TRAcP activity that was further identified as an isoenzyme associated with bone tissue. In contrast, the U937 cells did not express TRAcP activity as measured by gel electrophoresis. Both U937 cells and monocytes possess material that interferes with interpretation of the colorimetric assay of AcP. The presence of TRAcP in monocyte-derived macrophages further supports the relationship between phagocytic cells and bone osteoclasts.  相似文献   
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Objectives

To evaluate the use of shear wave elastography in assessment of kidney allograft tubulointerstitial fibrosis.

Methods

Shear wave elastography assessment was carried out by two independent operators in kidney transplant recipients who underwent allograft biopsy for clinical indications (i.e. rising creatinine >15% or proteinuria >1 g/day). Allograft biopsies were interpreted by the same pathologist according to the 2013 Banff Classification.

Results

A total of 40 elastography scans were carried out (median creatinine 172.5 μmol/L [interquartile range 133.8–281.8 μmol/L]). Median tissue stiffness at the cortex (22.6 kPa [interquartile range 18.8–25.7 kPa] vs 22.3 kPa [interquartile range 19.0–26.5 kPa], P = 0.70) and medulla (15.0 kPa [interquartile range 13.7–18.0 kPa] vs 15.6 kPa [interquartile range 14.4–18.2 kPa]) showed no significant differences between the two observers. Interobserver agreement was satisfactory (intraclass correlation coefficient of the cortex 0.84, 95% CI 0.70–0.92 and intraclass correlation coefficient of the medulla 0.88, 95% CI 0.78–0.94). The areas under the receiver operating characteristic curves for detection of tubulointerstitial fibrosis were estimated to be 0.75 (95% CI 0.61–0.89), 0.85 (95% CI 0.75–0.95) and 0.65 (95% CI 0.53–0.78) for cortical, medullary tissue stiffness and serum creatinine, respectively.

Conclusions

Shear wave elastography can be used as a non‐invasive tool to evaluate kidney allograft fibrosis with reasonable interobserver agreement and superior test performance to serum creatinine in detecting early tubulointerstitial fibrosis.  相似文献   
34.
BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion.  相似文献   
35.
骺板软骨细胞的体外培养及鉴定   总被引:2,自引:0,他引:2  
目的:建立体外培养及鉴定骺板软骨细胞的方法。方法:实验于2005-03/2006-05在苏州大学附属儿童医院骨科实验室完成。选用3只生后14~28d的新西兰幼兔,空气栓塞处死,暴露股骨下端和胫骨上端,分别取2处的骺板组织,将其剪切成1~3mm3的小块,经胰蛋白酶消化,接种于含150g/L牛血清的1640培养基中,饱和湿度培养,传代。①细胞接种后3h在倒置显微镜下观察细胞生长情况,见细胞贴壁后每天观察2次。②第2代细胞达到80%~90%左右汇合时采用常规苏木精-伊红染色,光镜观察细胞爬片情况。③第3代细胞爬片至细胞达到80~90%左右汇合时,采用苏木素染色3min,3%亮绿染色5min,蕃红花“O”染色5min,光镜观察细胞产生蛋白聚糖情况。④采用PCR检测细胞Ⅱ型胶原的表达。⑤采用四唑盐MTT比色法检测细胞活性。结果:①骺软骨细胞刚接种后呈大小不等之圆形悬浮于培养液中,3h后见大部分细胞贴壁,24h后贴壁细胞呈短梭形、圆形、三角形和不规则形,见细胞分裂相。48h后见细胞伸展明显,细胞分裂相每高倍镜视野可见多个。经隔日换液细胞生长至第5天,细胞呈聚集生长,达到汇合状态,将细胞传代。接种后第1代细胞2d后呈梭形,培养4d传至第2代,第2代细胞长满瓶底后,90%呈胞膜较厚的圆形,10%为梭形,第3代、第4代亦如此。传至第5代见肥大细胞增多,细胞松散,折光性减弱,呈凋亡状态。②细胞爬片后观察骺软骨细胞形态以梭形居多,同时也有圆形、三角形和不规则形。可见细胞分裂及细胞中的分泌小泡。③见细胞呈红色,无绿色,证明蕃红花“O”-亮绿染色阳性,显示所培养的细胞可以分泌蛋白聚糖。④PCR检测术所养细胞含有Ⅱ型胶原,电泳带在440bp上。⑤四唑盐MTT比色法检测显示,第3代骺软骨细胞的生长曲线近似倒“S”形,在第4,5,6天细胞呈对数生长,约在7,8,9,10d达平台期,至第12天细胞出现生长抑制。结论:建立了骺板软骨细胞的体外培养方法,并证实所培养出的细胞分泌蛋白聚糖和Ⅱ型胶原,具有软骨细胞的共同特点。  相似文献   
36.
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38.
Platelet aggregation requires the binding of adhesive proteins such as fibrinogen to the heterodimer of membrane glycoproteins IIb (GPIIb) and IIIa (GPIIIa). Human erythroleukemia (HEL) cells synthesize both GPIIb and GPIIIa. Using poly(A+) RNA purified from HEL cells, we constructed a cDNA library in the lambda gt10 phage vector. This library was screened with a 38mer oligonucleotide derived from a platelet GPIIIa peptide, and three overlapping cDNAs were isolated. The three inserts encompassed 3.5 kilobases (kb), including the entire coding region of mature GPIIIa (2,286 basepairs, bp) and 1.3 kb of 3' untranslated sequence. All 222 residues determined directly from platelet GPIIIa tryptic peptides exactly matched the HEL cell-deduced amino acid sequence. The HEL cell sequence matched a previously reported endothelial cell cDNA sequence except for eight nucleotides. Five of these nucleotide differences were silent changes consistent with genetic polymorphisms. The other three differences resulted in changes in the deduced amino acid sequence of GPIIIa; reexamination of the endothelial cell cDNA sequence in these three areas revealed that it is actually identical to the HEL cell sequence. The virtual identity of the endothelial and HEL cell cDNA sequences provides direct evidence that GPIIIa is a subunit common to cell-adhesion receptors present in more than one cell type. We localized the gene for GPIIIa to chromosome 17, the same chromosome to which we had previously mapped the gene for GPIIb.  相似文献   
39.

Back ground

Stroke produces a wide range of mental and emotional disorders. Neuropsychiatric complications associated with stroke may have negative effects on the social functioning, overall quality of life and the recovery of motor functioning of stroke survivors.

Objective

To determine the prevalence and nature of psychiatric morbidity among stroke patients attending neurology outpatient clinic of the University of Ilorin Teaching Hospital (UITH), Ilorin-Nigeria.

Methods

All patients with stroke aged 18 years and above at an outpatient neurology clinic in Ilorin, Nigeria were assessed for mental and emotional disorders using the Schedule for Clinical Assessment in Neuropsychiatry (SCAN) over one year (March 2009 to February 2010).

Results

Overall prevalence of psychiatric morbidity was 36.0% (30/83) among 83 patients who constituted the study population. Specific diagnoses recorded were depression (19.2%), generalised anxiety disorder (9.6%), harmful alcohol use (2.4%); dementia, somatoform disorder, phobia and delusional disorder each had a prevalence of 1.2%. Clinical and sociodemographic variables were not significantly associated with psychiatric morbidity.

Conclusion

Psychiatric disorders are often associated with stroke. Identifying and treating stroke patients with these psychiatric co-morbidities could thus help to improve the overall quality of life of these patients.  相似文献   
40.
Overpressure blast-wave induced brain injury (OBI) leads to progressive pathophysiologic changes resulting in a reduction in brain blood flow, blood brain barrier breakdown, edema, and cerebral ischemia. The aim of this study was to evaluate cerebral vascular function after single and repeated OBI. Male Sprague-Dawley rats were divided into three groups: Control (Naive), single OBI (30 psi peak pressure, 1 to 2 msec duration), and repeated (days 1, 4, and 7) OBI (r-OBI). Rats were killed 24 hours after injury and the basilar artery was isolated, cannulated, and pressurized (90 cm H2O). Vascular responses to potassium chloride (KCl) (30 to 100 mmol/L), endothelin-1 (10−12 to 107 mol/L), acetylcholine (ACh) (1010 to 104 mol/L) and diethylamine-NONO-ate (DEA-NONO-ate) (10−10 to 104 mol/L) were evaluated. The OBI resulted in an increase in the contractile responses to endothelin and a decrease in the relaxant responses to ACh in both single and r-OBI groups. However, impaired DEA-NONO-ate-induced vasodilation and increased wall thickness to lumen ratio were observed only in the r-OBI group. The endothelin-1 type A (ETA) receptor and endothelial nitric oxide synthase (eNOS) immunoreactivity were significantly enhanced by OBI. These findings indicate that both single and r-OBI impairs cerebral vascular endothelium-dependent dilation, potentially a consequence of endothelial dysfunction and/or vascular remodelling in basilar arteries after OBI.  相似文献   
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