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371.
Aim: There are two known oestrogen receptors (ER), oestrogen receptor α (ERα) and the recently cloned oestrogen receptor β (ERβ). ERα mRNA has been detected in mouse, rat, bovine and human skeletal muscle. ERβ mRNA has been detected in bovine skeletal muscle. To our knowledge, no study has investigated the expression of oestrogen receptor β in human skeletal muscle. Therefore, the primary aim of the present investigation was to study ERβ mRNA and protein expression in human skeletal muscle. In addition the ERα expression was also studied. Methods: Muscle biopsies were taken from vastus lateralis in six healthy adults (three women and three men). mRNA expression was detected with real‐time PCR (TaqMan) and protein localization by immunohistochemistry. Results: A clear expression of ERα and ERβ mRNA was seen in skeletal muscle in all subjects. The ERα mRNA expression was 180 fold higher compared with that of ERβ mRNA. Immunohistochemistry demonstrated positive staining for ERβ, but not for ERα, with localization to the nuclei of skeletal muscle fibres. On average, 70% of all nuclei were ERβ‐positive. Conclusion: The present study shows for the first time ERβ mRNA and protein expression in human skeletal muscle tissue in both males and females.  相似文献   
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Abstract Avulsed human permanent teeth subjected to a minimum of 1 h dry extraoral storage before replantation were followed radiographically for an average of 4.8 years. The depth of root resorption cavities was assessed using a radiographic index, and the rate of root resorption was defined as the index change over time. The frequency of inflammatory and replacement resorption was determined at each observation time. Replacement resorption increased in frequency with time in all patients. In teeth endodontically treated within 3 weeks of replantation, minimal inflammatory resorption was found regardless of the age of the patients. In teeth where endodontic treatment was performed more than 3 weeks after replantation, the frequency of inflammatory resorption was significantly higher in young patients but not in older patients, up to more than 3 years after replantation. The rate of root resorption was found to be related to age. In patients 8–16 years old at the time of avulsion the rate of root resorption was significantly higher compared with patients 17–39 years old. Age had a higher impact on the rate of root resorption compared with the delay in endodontic treatment after replantation. It was concluded that a tooth replanted with a necrotic periodontal membrane will become ankylosed and resorbed within 3–7 years in young patients, whereas a tooth replanted under similar conditions in older patients may remain in function for a considerably longer time.  相似文献   
375.
Aims: Previous studies have demonstrated that pancreatic islet blood flow is crucially dependent on blood glucose concentration. Thus, hyperglycaemia increases and hypoglycaemia decreases islet blood perfusion, by a combination of nervous and metabolic signals. The aim of the present study was to evaluate if hyperinsulinaemia, without associated hypoglycaemia, affects islet blood flow. Methods: Thiobutabarbital‐anaesthetized Wistar–Furth rats were subjected to an euglycaemic, hyperinsulinaemic clamp, that is they were infused for 60 min with either saline, insulin (18 mU kg?1 min?1), glucose (27 mg kg?1 min?1) or both glucose and insulin. This was followed by islet blood flow measurements with a microsphere technique. Results: Animals receiving only glucose doubled their blood glucose and serum insulin concentrations, whereas rats receiving only insulin had blood glucose concentrations <2 mmol L?1 and a 10‐fold increase in serum insulin concentrations. Animals given simultaneous glucose and insulin had normal blood glucose concentrations but a 10‐fold increase in serum insulin concentrations. Total pancreatic blood flow was unaffected in all animals. Islet blood flow was increased in hyperglycaemic and decreased in hypoglycaemic rats compared with control rats. Islet blood flow did not differ between clamped and control rats. Conclusions: Serum insulin concentration per se does not affect islet blood flow, whereas the ambient blood glucose concentration is of major importance in this context.  相似文献   
376.
In response to increased shear stress, vascular endothelial cells release adenosine triphosphate (ATP) by an unknown mechanism. We have investigated this mechanism using different approaches. First, we discovered that quinacrine, used to locate intracellular stores of ATP bound to peptides, displayed a granular fluorescence, typical of vesicular storage. Second, we found that two inhibitors of vesicular transport (monensin and N-ethylmaleimide) produced a highly significant reduction in the release of ATP from vascular endothelial cells in response to increased shear stress. Preliminary experiments using inhibitors of the cystic fibrosis transmembrane regulator, the sulfonylurea receptor, and the multidrug resistance protein showed no involvement of these ATP-binding cassette transporter proteins (previously characterized in endothelial cells) in the mechanism of release of ATP. We suggest, therefore, that the release of ATP from vascular endothelial cells, like that of nerve cells, is probably by vesicular exocytosis.  相似文献   
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378.
Two quantitative duplex real‐time PCR assays were developed for co‐amplification of human albumin and cytomegalovirus (CMV) or Epstein Barr virus (EBV) genes after automated extraction on whole blood, and compared two units for expressing viral DNA loads (copies per ml of blood or per 106 peripheral blood leukocytes (PBLs)) on 1,138 positive samples. Both PCRs were characterized by high sensitivity, reproducibility, and linear range. Automated extraction by a MagNA Pure LC Instrument was shown to be more efficient when peripheral blood cell count was inferior to 5 × 109 PBLs/L. Albumin co‐amplification allows the detection of PCR inhibitors and normalization of viral load according to the number of cells calculated in the sample. The two ways of expressing viral load results were highly correlated, but quantitative differences varied in relation to variations of blood cell count. As these two viruses are highly cell associated, viral loads can be underestimated in patients with leucopenia. In the setting of pre‐emptive strategies during CMV infection, the units in which results are expressed can influence clinical management, as illustrated in this article. J. Med. Virol. 81:90–98, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
379.

Background:

Cytology-based diagnostics of squamous cervical cancer (SCC) precursor lesions is subjective and can be improved by objective markers.

Methods:

IHC-based analysis of ANXA6, HSP27, peroxiredoxin 2 (PRDX2), NCF2, and tropomyosin 4 (TPM4) during SCC carcinogenesis.

Results:

Expression of ANXA6, HSP27, PRDX2, and NCF2 in the cytoplasm of dysplastic cells increased from cervical intraepithelial neoplasia 2/3 (CIN2/3) to microinvasive cancer. Invasive SCC showed lower expression of TPM4 than CIN and normal epithelium. CIN2/3 with the highest sensitivity and specificity differed from normal epithelium by cytoplasmic expression of HSP27. Patients with cytoplasmic HSP27 expression in SCC deviating from that observed in normal epithelium had worse relapse-free (P=0.019) and overall (P=0.014) survival. Invasive SCC with the highest sensitivity and specificity differed from normal epithelium by expression of PRDX2 and TPM4 in the cytoplasm, from CIN2/3 by the expression of ANXA6 and TPM4 in the cytoplasm, and from microinvasive SCC by the expression of PRDX2 and ANXA6 in the cytoplasm. The number of sporadic ANXA6+ cells between the atypical cells increased from CIN2/3 to invasive SCC.

Conclusion:

Detection of expression changes of the proteins ANXA6, HSP27, PRDX2, NCF2, and TPM4 in SCC precursor lesions may aid current cytological and pathological diagnostics and evaluation of prognosis.  相似文献   
380.

Background

Even though transurethral resection of the prostate remains the gold standard treatment for lower urinary tract symptoms (LUTS) refractory to medical therapy, photoselective vaporization of the prostate (PVP) has become a popular alternative. Early PVP studies seem encouraging, but few data exist regarding the effect of PVP on sexual function at long-term follow-up.

Objective

Our aim was to evaluate the impact of PVP on erectile function (EF) at long-term follow-up in men with LUTS due to benign prostatic hyperplasia (BPH).

Design, setting, and participants

One hundred forty-nine consecutive patients who underwent a prostate vaporization with the GreenLight laser performed by a single surgeon (FB) were prospectively enrolled in this study.

Intervention

All patients underwent PVP with the GreenLight laser performed by one experienced surgeon.

Measurements

All patients were evaluated by International Index of Erectile Function (IIEF-5) preoperatively and at 1, 3, 6, and 12 mo and then once a year. At each visit, the questionnaires were collected, and each patient's maximum flow rate and postvoid residual volume were measured with ultrasound. Biologic data were also collected at each visit, including prostate-specific antigen, creatinine, and bacterial urine culture.

Results and limitations

One hundred forty-nine patients were enrolled in the study. Median patient age was 74 yr. Urinary function was significantly improved over baseline in both men with normal or abnormal preoperative erectile function. Energy used was 255 ± 129 kJ. Hospitalization stay was 2.2 ± 3.1 d. Other than a temporary difference at 1 yr, IIEF-5 scores were comparable preoperatively and postoperatively if we consider all the population. However, considering patients with preoperative IIEF-5 >19, the postoperative IIEF-5 scores were significantly decreased at 6, 12, and 24 mo.

Conclusions

Sexual function appears to be maintained after PVP; however, in patients with normal preoperative EF, we showed a significant decrease in EF after PVP.  相似文献   
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