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1.
Using real-time PCR and immunohistochemistry, we have examined the expression of carbonic anhydrase isozymes (CA) I, II, III, IV, IX, XII, XIII and XIV in the brain, kidney, stomach and colon of the wild-type, CA II-deficient ( Car2−/− ), and CA IX deficient ( Car9−/− ) mice. The expression of Car4, Car12, Car13 and Car14 mRNAs did not show any significant deviations between the three groups of mice, whereas both groups of CA deficient mice showed decreased expression levels of Car1 in the colon and Car3 in the kidney. The Car2 mRNA level was greatly reduced but not completely abolished in all four tissues from the Car2−/− mice in which no CA II protein was expressed. Sequencing the Car2 cDNA isolated from C57BL6 Car2−/− mice revealed two nucleotide differences from the wild-type C57BL6 mice. One is a silent polymorphism found in Car2 mRNA from wild-type DBA mice, which is the strain that provided the original mutagenized chromosome. The second change is a mutation that causes prematurely terminated translation at codon 155 (Gln155X). Car9 mRNA and CA IX protein expression levels were up-regulated about 2.5- and 3.6-fold, respectively, in the stomach of the Car2−/− mice. These results suggest that the loss of function of cytosolic CA II in the stomach of Car2−/− mice leads to up-regulation of an extracellular CA, namely CA IX, which is expressed on the cell surface of the gastric epithelium.  相似文献   
2.
Carbonic anhydrase isoenzyme IX, MN/CA IX, is a recently discovered member of the carbonic anhydrase (CA) gene family with a suggested function in acid-base balance, intercellular communication, and cell proliferation. Increased expression of MN/CA IX has been observed with certain epithelial tumors. We investigated the expression of MN/CA IX in 69 colorectal neoplasms, consisting of 1 juvenile polyp, 8 hyperplastic polyps, 39 adenomatous lesions, 21 carcinomas, and 7 metastases. Tissue sections were immunostained with a monoclonal antibody specific to MN/CA IX. The proliferative activity of the tumor cells was evaluated by Ki-67 antigen immunoreactivity. The hyperplastic polyps showed a weak or moderate reaction for MN/CA IX only in the cryptal epithelium, as did the normal intestinal mucosa. The adenomas showed immunoreactivity mainly in the superficial part of the mucosa, whereas the distribution in the carcinomas and metastases was more diffuse. Comparative immunostaining of serial sections for Ki-67, a well established marker of cell proliferation, confirmed that MN/CA IX is expressed in areas with high proliferative capacity. Our results show abnormal MN/CA IX expression in colorectal neoplasms, suggesting its involvement in their pathogenesis. The co-occurrence of MN/CA IX and Ki-67 in the same tumor cells indicates its potential for use as a marker of increased proliferation in the colorectal mucosa.  相似文献   
3.
The quality and usefulness of the EuroTransMed (ETM) international satellite medical educational programmes were assessed. Medical educational sessions are broadcast once a week from London in English to over 140 sites in Europe. The aim is to provide an update of medical information to physicians as a part of their continuing medical education (CME). A questionnaire was distributed to two groups of postgraduate medical trainees, internists and family doctors. The groups viewed two video-recordings of the satellite broadcasts, translated into Polish. The first programme was watched by 219 doctors and the second by 265. There was a 96% response rate to the questionnaires. Results suggest that the ETM satellite programmes are both relevant and of good quality, but are of limited usefulness to the target audience. These limitations result mainly from a shortage of time available for such a form of education, as well as from difficulty understanding the English broadcasts, because of a lack of fluency among general practitioners in Poland.  相似文献   
4.
5.

Background &; Aims

Wilson disease (WD) is an inherited disorder of copper disposition caused by an ATP7B transporter gene mutation, leading to copper accumulation in predisposed tissues. In addition to a genetic predisposition, other factors are likely to contribute to its clinical manifestation. The aim of the study was to assess whether oxidative stress affects the phenotypic manifestation of WD.

Methods

In 56 patients with WD (29 men; 26 with the hepatic form, 22 with the neurologic form, and eight asymptomatic; mean age 38.5?±?12 years), total serum antioxidant capacity (TAC) and inflammatory parameters (hs-CRP, IL-1??, IL-2, IL-6, IL-10, and TNF-??) were analyzed and related to the clinical manifestation, and mutations of the ATP7B gene. The control group for the TAC and inflammatory parameters consisted of 50 age- and gender-matched healthy individuals.

Results

WD patients had a significantly lower TAC (p?Conclusions Data from our study suggest that the increased oxidative stress contributes significantly to the clinical manifestation of WD; as a lower TAC is associated with the neurological symptoms in WD patients.  相似文献   
6.
ObjectiveRetrospective data analyses have suggested that carbonic anhydrase IX (CAIX) may have a predictive role in patients with metastatic clear cell renal cell carcinoma (ccRCC) receiving high dose interleukin-2 or sorafenib. We examined the predictive value of CAIX in estimating treatment outcome in patients receiving sorafenib vs. placebo as part of the Treatment Approaches in Renal Cancer Global Evaluation Trial (TARGET) study.Materials and methodsParaffin embedded tumor tissues were collected from 133 patients from the TARGET study (n = 903). The percentage of CAIX-positive cells was assessed by a single pathologist. The impact of CAIX expression on progression-free survival (PFS, primary endpoint) and tumor shrinkage (TS, secondary endpoint) was analyzed.ResultsClinical characteristics were similarly distributed between patients with low vs. high CAIX staining, as well as patients with available CAIX data vs. not. Median PFS for patients with high CAIX vs. low CAIX expression was 5.5 and 5.4 months, respectively, on the sorafenib arm (P = 0.97), and 1.5 and 1.7 months on the placebo arm (P = 0.76). Median TS for patients with high CAIX status was ?14.9% vs. ?12.6% in patients with low CAIX status (P = 0.63) on the sorafenib arm, and +1.3% (high CAIX) vs. +4.8% (low CAIX) in patients on the placebo arm (P = 0.60).ConclusionsDespite suggestive retrospective evidence, data from the TARGET study did not find CAIX expression status to be either predictive of clinical benefit for treatment with sorafenib or of prognostic value in patients with metastatic ccRCC following cytokine therapy.  相似文献   
7.

Introduction and hypothesis

Information on urethral bulking therapy in women after previous pelvic radiotherapy is lacking. This study compared the safety and efficacy of polyacrylamide intraurethral injections in patients with and without previous radiotherapy.

Methods

A total of 46 patients with severe stress urinary incontinence (SUI) were enrolled in this multicenter prospective trial. Group A consisted of 24 patients with previous radiotherapy to the pelvis for the treatment of a gynaecological malignancy. Group B consisted of 22 patients without previous radiotherapy. All patients were treated with a transurethral injection of a bulking solution (Bulkamid). The average follow-up was 12.4 months. The paired Wilcoxon test was used to compare the results before and after the procedure within the groups, and the two-sample Wilcoxon test was used for comparisons between groups.

Results

Complete continence was achieved in 25 % of patients in group A and in 36.4 % of patients in group B. Significantly reduced urine leakage was observed in both groups (p?=?0.0164 in group A and p?=?0.0002 in group B). The total scores in the International Consultation on Incontinence Questionnaire decreased by 5.2 in group A (p?=?0.0000) and 6.36 in group B (p?=?0.0001). The scores for the Total Patient Perception of Bladder Condition decreased by 1.54 in group A (p?=?0.0001) and 2.59 in group B (p?=?0.0000), with a significant difference between groups (p?=?0.0224). No clinically significant changes in urodynamic parameters were observed. No severe adverse events were noted.

Conclusions

Based on our results, we conclude that urethral bulking therapy is a valuable treatment option in patients with severe SUI who have undergone pelvic radiotherapy for the treatment of gynaecological malignancy.
  相似文献   
8.
Titanium dioxide modified with 3 wt% La was prepared via a green freeze-casting method, and its photocatalytic activity was tested in terms of its ability to degrade 4-chlorophenol (4-CP) and remove total organic carbon (TOC). Under annealing conditions, the freeze-cast precursor was transformed into an La-modified anatase with a well-defined 2D TiO2 nanosheet morphology. Rietveld refinement of the X-ray diffraction patterns confirmed the substitutional nature of the La cation that induced local structural variations and involved subtle ion displacement in the TiO2 lattice due to the ionic size effect. Despite nearly identical tetragonal structures, replacement of Ti with La alters the photocatalytic activity through a reduction in band gap energies and an increase in charge carrier mobility. Material annealed at 650 °C exhibited the highest photocatalytic performance and achieved efficient TOC removal. Upon annealing at 800 °C, nanoscale lanthanum-enriched regions were generated due to the diffusive migration of La cations and phase transition from anatase to rutile. The La3+ cation, acting as a structural promoter, supported 2D TiO2 growth with well controlled crystallite size, surface area and porosity. La3+ could be regarded as a potential electronic promoter that can reduce the band gap of 2D TiO2 nanosheets and can provide a signature of the electron transfer and carrier charge separation. Both methods, kinetics of degradation of 4-CP and TOC, provided similar results, revealing that the photocatalytic activity under UV light irradiation increased in the order 950C < 500 °C < 800 °C < 650 °C < TiO2-P25.

Titanium dioxide modified with 3 wt% La was prepared via a green freeze-casting method, and its photocatalytic activity was tested in terms of its ability to degrade 4-chlorophenol (4-CP) and remove total organic carbon (TOC).  相似文献   
9.
10.
The purpose of this study was to investigate the effects of expression of CA IX, a marker of hypoxia, on outcome in bladder cancer. Immunohistochemistry was used to examine expression of CA IX in archival tissues of patients included in various therapeutic trials for transitional cell carcinoma (TCC) of the bladder. Data were collected on 57 patients who first presented with either invasive or superficial bladder cancer. Median follow-up for the 19 alive patients was 110 months (range 12 months to 14 years and 7 months). Median survival was 48 months (95% CI 35-110 months). Median survivals based on CA IX expression were as follows: there was a non-significant trend towards shorter survival for tumour expressing CA IX weakly (median 45 vs. 70 months, p=0.21). The hazard ratio for this variable is 1.5 (95% CI 0.8-3.0). Significantly more superficial bladder cancers than invasive cancers strongly expressed CA IX (82% vs. 52%; p=0.03). For non-invasive bladder cancer (n=28), CA IX positive patients had a median survival of 111 months while the median has not yet been achieved for CA IX negative patients (p=0.9). For invasive bladder cancer (n=29), CA IX positive patients had a median survival of 18 months as compared to 26 months for CA IX negative patients (p=0.94). There was a trend towards longer survival for tumour expressing CA IX strongly. This is likely to be a reflection of the significantly higher rate of strong CA IX expression in non-invasive cancers influencing these survival data.  相似文献   
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