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81.
Objectives: To assess the systematic health effects on the liver, kidney, and haematological function tests of workers in semiconductors in Taiwan.

Methods: 926 workers of a semiconductor plant in Taiwan in July 1995 were investigated. Complete blood tests including liver, kidney, and haematological functions were available from 227 workers.

Results: There was a significantly lower mean (SD) white blood cell (WBC) count in male workers of photolithography (5870 (1190)/mm3, p=0.003) and implantation (6190 (1150)/mm3, p=0.018) than that of male control workers (7350 (1660)/mm3). There was a significantly higher prevalence of leukopenia in male photolithography workers (6 of 20; 30%) than in male control workers (1 of 18; 5.6%), the crude odds ratio (OR) was 7.3 (95% confidence interval (95% CI) 1 to 55.6), and the multivariate adjusted OR was 8.1 (95% CI 0.83 to 78.3). The tests for serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), γ glutamyl transferase (RGT), and creatinine were not significant among male workers. Female workers in photolithography had abnormal SGPT and RGT of borderline significance, the multivariate adjusted ORs were 9.6 (95% CI 0.86 to 107) and 6.35 (95% CI 0.53 to 75.8), respectively.

Conclusions: This study suggests that leukopenia is a potential health effect in male fabrication workers of the semiconductor industry. The tasks of the process, maintenance, and equipment engineers which consisted mostly of men put them at risk for intermittent short term peak exposure to glycol ethers, ionising radiation, arsenic, or other toxins. The findings of this medical surveillance are significant; however, a further investigation of the aetiological factors and the subsequent health effects is necessary.

  相似文献   
82.
BACKGROUND: With the help of a measurement feedback system, the treatment strategy for individual patients with rheumatoid arthritis (RA) can be adjusted to achieve optimal control of disease activity. OBJECTIVE: To study whether a measurement feedback system is effective in reducing disease activity in patients with RA. METHODS: Forty eight rheumatologists and 264 patients participated in a controlled clinical trial. A three month control period was followed by a 12 month period, where feedback on disease activity, disability, and damage was provided to the rheumatologist. The primary outcome measure was the rheumatoid arthritis disease activity index (RADAI). RESULTS: The feedback system was used for 142/228 (62%) patients. Disease modifying antirheumatic drug changes occurred in 69/169 (41%) patients. In patients with high disease activity and feedback use (n=70), the RADAI decreased in the feedback period by -0.27 points per 30 days (p<0.05), as compared with the control period. Patients for whom the feedback system was used had a better outcome than non-users. CONCLUSION: Much more training on the use of a feedback system and outcome measures, as well as the inclusion of explicit treatment guidelines will be necessary to increase the clinical use of measurement feedback and, possibly, to reduce disease activity for a larger number of patients with RA.  相似文献   
83.
84.
This study evaluated the treatment of intraosseous vascular malformation of the mandible. We analysed the medical records of 12 patients treated at the Salpêtrière Hospital (Paris, France) for vascular malformation of the mandible between 1965 and 1996. There were six male and six female patients, with a mean age of 16 years. The mean follow-up time was ten years. The treatment was surgery (enucleation or resection) or interventional radiology (arterial embolization or transosseous transcutaneous embolization).There are several indications for treatment, including age, and the size and type of vascular malformation (active or passive).  相似文献   
85.
TGF-beta1 induces accumulation of dendritic cells in the odontoblast layer   总被引:3,自引:0,他引:3  
TGF-beta1 released from dentin degraded by bacterial or iatrogenic agents is suspected to influence dental pulp response, including the modulation of cell migration. To determine the consequences of TGF-beta1 action on pulp immune cells, we analyzed, by immunohistochemistry, the effect of transdentinally diffusing TGF-beta1 on their localization in a human tooth slice culture model. TGF-beta1 induced an accumulation of HLA-DR-positive cells in both odontoblast and subodontoblast layers of the stimulated zone. Together with HLA-DR, these cells co-expressed Factor XIIIa and CD68, two features of immature antigen-presenting dendritic cells (DC), as well as the TGF-beta1 specific receptor TbetaRII. In contrast, no effect could be detected on the localization of either mature DC-LAMP-positive DC or of T- and B-lymphocytes. Analysis of these data suggests that TGF-beta1 released from dentin degraded by bacterial or iatrogenic agents could be involved in the immune response of the dental pulp resulting from tooth injury.  相似文献   
86.
87.
CONTEXT: The human and financial costs of academic failure amongst medical students are extremely high. Often, remedial support is infrequently available or is available only for students failing their final examinations. We describe the design, implementation and preliminary evaluation of a remedial programme (RP) for students who experience academic difficulties. METHODS : A total of 24 students were identified from Years 4 and 5 of the undergraduate medical course at our medical school. Students invited to participate were identified following failure in summative and/or continuous assessment processes. Students underwent an individual educational diagnosis by means of free discussion and a semi-structured interview. Each negotiated a problem list, action plan and learning contract with course tutors. Of the 24 students, 16 received academic support and tutorials. Tutorial content was determined by individual students and took place over a 6-12-month period, initially individually and subsequently in pairs. Regular feedback and appraisal occurred. Information was delivered to the medical school academic progress review system. Student satisfaction was investigated and subsequent examination scores reviewed. RESULTS : The causes of academic failure were widespread and ranged from deficient study skills to financial, domestic and emotional problems. In contrast, the subjects in which students had difficulty were remarkably similar, in that they all related to core clinical skills and frequently involved communication skills. Students enjoyed the programme, reported improved motivation both for study and for their chosen career and demonstrated a greatly improved pass rate in subsequent examinations. CONCLUSIONS : The causes of academic failure in undergraduate medical students are diverse and are often not academic in origin. Students can benefit from an individually tailored remedial programme and go on to success in subsequent parts of the curriculum. Provision of individually tailored remedial teaching is labour-intensive and requires full faculty support.  相似文献   
88.
We tested the benefit of using buffered propionic acid (BPA) as a means of preventing farmer's lung disease (FLD). BPA, a new formulation of propionic acid, a hay preservative with no deleterious effect on farm machinery or cattle, reduces the development of micro-organisms in hay. Twenty pairs of round bales were analysed for concentration of micro-organisms measured in the winter following hay treatment. Each pair included one untreated bale and one bale treated with BPA during haymaking. Our results showed the following decreases in concentration in treated bales: total fungal species, 40% (P < 0.05); Eurotium amstelodami (the main species found), 65% (P < 0.01); and thermophilic actinomycetes, 60% (not significant), respectively. We conclude that BPA could be used to prevent FLD.  相似文献   
89.
A randomised phase II trial was initiated to explore the feasibility of concomitant cisplatin and radiotherapy with conventional fractionation (CF) or multiple fractions per day (MFD) for patients with locally advanced head and neck malignancies. The MFD schedule was designed to achieve higher tumour concentrations of cisplatin at the time of irradiation by reducing the number of radiation treatment weeks from 7 to 3, allowing recovery from side-effects of both irradiation and cystostatic drugs during the rest periods, while keeping the same total dose and overall treatment time. Patients were randomised between a conventional fractionation scheme (CF) of 70 Gy in 7 weeks with 2 Gy per fraction with a daily dose of 6 mg/m(2) cisplatin and a modified fractionation scheme (MFD) delivering three fractions of 1.6 Gy per day, in weeks 1, 4 and 7, keeping the same overall treatment time and total dose. In the modified treatment regime, a daily dose of 10 mg/m(2) cisplatin was administered. 53 patients were entered in this trial and radiotherapy was given according to the schedule to all patients in both treatment arms. Cisplatin was given during the whole course of radiotherapy to only one quarter of the patients in the CF arm, stopping mostly after 5-6 weeks due to bone marrow depression and kidney toxicity, while patients in the MFD arm received it according to schedule. No difference was observed in acute and late toxicity in both treatment arms, while a similar or even better tumour response was obtained with MFD. A 67% higher daily dose of cisplatin concomitant with irradiation could be given in a 3-week multiple fractionation per day schedule, as opposed to the cisplatin given in the conventional daily fractionation schedule of 7 weeks with the same total radiation dose. Similar acute and late toxicities were seen in both treatment arms.  相似文献   
90.
The exposure of cells to -benzyl- 2-acetylguanosine (BNAG) and several guanine derivatives is known to reduce -alkylguanine-DNA alkyltransferase (AGAT) activity and to decrease the resistance of methyl enzyme repair positive (Mer ) cells to chloroethylnitrosoureas (CENUs) and. We evaluated the influence of AGAT activity inhibition by BNAG on the ability of two CENUs, 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and 3-(2-chloroethyl)-1-(2-methylsulphonyl)ethyl-3-nitrosourea (cystemustine), to induce an apoptotic response in two melanoma cell lines, M3 Dau (Mer ) and IPC 227F (Mer ). The apoptotic morphology of cells was assessed by microscopy after Wright-Giemsa or Hoechst 33342 staining of cells, and DNA internucleosomal cleavage was demonstrated by the ladder-like pattern of DNA separated by agarose gel electrophoresis. The concentration-dependent number of apoptotic cells assessed using a terminal deoxynucleotidyl transferase-mediated dUTP-fluorescein nick-end labelling (TUNEL) assay 72 h after BCNU or cystemustine treatment (0-400 microM for 2 h) was increased by prior AGAT depletion with BNAG pretreatment (300 microM for 4 h) in Mer cells. These results suggest that the DNA lesions on the position of guanine are a key event in inducing an apoptotic response in melanoma cells. We also observed that cystemustine was a more potent inducer of apoptosis than BCNU, and that the synergism with BNAG was more potent with cystemustine than with BCNU. These results suggest that the nature of the CENUs associated with an AGAT inhibitor is a determinant factor in forecasting the clinical efficacy of the association, especially in melanoma.  相似文献   
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