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71.
72.
The increasing prevalence of HIV infection in urban India together with limited financial resources necessitates judicious HIV testing. This prospective study was undertaken to determine the utility of selective screening for HIV infection based on five clinical risk factors reported in African children. The study was conducted at the Departments of Paediatrics and Microbiology, LTMG Hospital, Bombay, India between September 1998 and 2000. The children were enrolled after taking informed consent from their parents. The HIV seroprevalence rate was determined in children (aged 1 month to 12 years) consecutively admitted with severe malnutrition, serious pyogenic infections (pneumonia, pyogenic meningitis, septicaemia), disseminated tuberculosis, chronic diarrhoea and oral candidiasis, present either singly or in combination. Children above 18 months of age were diagnosed as being infected with HIV if they tested positive by two different HIV enzyme-linked immunosorbent assay (ELISA) tests. In children less than 18 months of age the diagnosis of HIV infection was made if they were ELISA positive and also fulfilled the WHO criteria for symptomatic HIV infection. Of a total 204 children (110 male, 94 female) screened, 24 (11.8 per cent) were diagnosed as HIV-infected. The HIV seropositive rate was highest in children having oral candidiasis (40.6 per cent), followed by chronic diarrhoea (18.2 per cent), disseminated tuberculosis (16.2 per cent), severe malnutrition (14.4 per cent), and serious pyogenic infections (11.2 per cent). Only the presence of oral candidiasis was a significant independent risk factor for predicting HIV infection (p < 0.0001). However, as the number of risk factors concomitantly present increased, the chances of the child being infected with HIV also increased significantly (p < 0.001). Our study shows that clinically-directed selective screening does have a practical role in diagnosing HIV infection in a resource-poor setting.  相似文献   
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BACKGROUND: Stent-based delivery of sirolimus (SRL) has shown reduction in neointimal hyperplasia and restenosis. The purpose of this study was to evaluate the chronic vascular response and the expression of cell cycle regulators after SRL-eluting stent implantation in a porcine coronary model. METHODS: Forty-nine pigs underwent placement of 109 oversized stents (control, n=54, SRL (140 microg/cm(2)), n=55) in the coronary arteries with histologic analysis and Western blot (PCNA, p27(kip1), CD45, MCP-1, IL-2, IL-6, TNF-beta) at 3, 30, 90 or 180 days. RESULTS: At 3 days, the mean thrombus area was similar for control (0.38+/-0.19 mm(2)) and SRL (0.29+/-0.09 mm(2)) stents. After 30 days, the mean neointimal area was significantly less for the SRL (1.40+/-0.35 mm(2)) versus the control stents (2.94+/-1.28 mm(2), p<0.001). At 90 and 180 days, the mean neointimal area was similar for the SRL (3.03+/-0.92 and 3.34+/-0.99 mm(2)) as compared with control stents (3.45+/-1.09 and 3.65+/-1.23 mm(2)). Western blot analysis demonstrated an increased expression of p27(kip1) in the vessel wall at 90 days for the SRL versus control stents (p=0.05) but with increased levels of PCNA in the SRL as compared with control stents (p=0.003). CONCLUSION: SRL-eluting stents favorably modulate neointimal formation for 30 days in the porcine coronary model. Long-term inhibition of neointimal hyperplasia is not sustained presumably due to delayed cellular proliferation despite increased levels of the cyclin-dependent kinase p27(kip1) in the vessel wall.  相似文献   
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The aim of this study was to evaluate the role of retinoblastoma protein (pRb), alone and in combination with p16, as a predictive marker for metastases in non-sentinel nodes in cases where the sentinel node showed metastatic breast carcinoma. Paraffin blocks of lymph nodes from 48 patients with metastatic breast carcinoma were immunostained with a monoclonal antibody to retinoblastoma protein (PharMingen). Results were compared with known prognostic parameters of the primary tumor, estrogen and progesterone receptor status, proliferation index, and p16 (DAKO) expression. Lymph nodes from 38 of the 48 (79%) cases were pRb positive. There was no correlation of pRb staining alone with the primary tumor parameters studied or the proliferative index of the metastatic tumor. In 16 patients with both a sentinel node biopsy and an axillary lymph node dissection, 8 (50%) had metastatic breast carcinoma. The sentinel nodes of three of these eight patients (38%) were pRb negative (positive predictive value of 60% vs. 73% for p16). The remaining eight patients (50%) had no metastases in non-sentinel nodes, even though their sentinel nodes had metastatic breast carcinoma; six of these eight patients (75%) were pRb positive (negative predictive value of 55% vs. 83% for p16). pRb and p16 staining results combined showed that pRb-negative/p16-positive cases were associated with non-sentinel node metastases (positive predictive value of 100%) as well as poor prognostic parameters. Patients with the opposite staining profile (pRb positive and p16 negative) were mostly without non-sentinel node metastases (negative predictive value of 75%). Cases negative for both pRb and p16 were consistently associated with a better prognostic phenotype and absence of additional axillary node metastases. In conclusion, the presence or absence of pRb in sentinel nodes is of little predictive value for non-sentinel node metastases unless taken in conjunction with the presence of p16 staining. Instead, it appears to enhance the positive predictive value of p16 in determining the presence of non-sentinel node metastases. Due to the limited subgroup sample size in this study, clinical guidelines cannot be suggested as yet, but further research focused on the pRb-negative/p16-positivie and pRb-negative/p16-negative phenotypes may yield beneficial results.  相似文献   
78.

Purpose

We explored the impact of obesity, body composition, and genetic polymorphisms on the pharmacokinetics (PK) of daunorubicin in children with cancer.

Patients and methods

Patients ≤21 years receiving daunorubicin as an infusion of any duration <24 h for any type of cancer were eligible. Plasma drug concentrations were measured by high-performance liquid chromatography. Body composition was measured by dual-energy X-ray absorptiometry. Obesity was defined as a BMI >95 % for age or as body fat >30 %. NONMEM was used to perform PK model fitting. The Affymetrix DMET chip was used for genotyping. The impact of genetic polymorphisms was investigated using SNP/haplotype association analysis with estimated individual PK parameters.

Results

A total of 107 subjects were enrolled, 98 patients had PK sampling, and 50 patients underwent DNA analysis. Population estimates for daunorubicin clearance and volume of distribution were 116 L/m2/h ± 14 % and 68.1 L/m2 ± 24 %, respectively. Apparent daunorubicinol clearance and volume of distribution were 26.8 L/m2/h ± 5.6 % and 232 L/m2 ± 10 %, respectively. No effect of body composition or obesity was observed on PK. Forty-four genes with variant haplotypes were tested for association with PK. FMO3-H1/H3 genotype was associated with lower daunorubicin clearance than FMO3-H1/H1, p = 0.00829. GSTP1*B/*B genotype was also associated with lower daunorubicin clearance compared to GSTP1*A/*A, p = 0.0347. However, neither of these associations was significant after adjusting for multiple testing by either Bonferroni or false discovery rate correction.

Conclusions

We did not detect an effect of body composition or obesity on daunorubicin PK. We found suggestive associations between FMO3 and GSTP1 haplotypes with daunorubicin PK that could potentially affect efficacy and toxicity.  相似文献   
79.
Aim of the study: The monitoring of antiepileptic drugs (AEDs) in clinical setting is important for measuring the efficacy of drugs and their safety and in personalizing drug therapy. We investigated the levels of AED, carbamazepine (CBZ), phenytoin (PHT) and phenobarbital (PHB), to understand their association in saliva compared with those in serum during the therapy. Materials and methods: In this study, we performed a prospective study of 116 persons with epilepsy (PWE; mean age 26.90 ± 11.83 years). Serum and saliva samples were collected at trough levels from the patients, who were under the treatment of CBZ, PHT and PHB either alone or in combination of these drugs for at least three months. The drug levels were assessed by high-performance liquid chromatography. Results and conclusions: The number of males (n = 88; 75.86%) was higher than females (n = 28; 24.14%) among the recruited patients. The intake of CBZ, PHT and PHB was observed in 49.14%, 68.10% and 38.79% of PWE, respectively. The levels of these AEDs showed a significant correlation (p < 0.05) between serum and saliva. Interestingly, the levels of mono-therapy or bi-therapy showed a significant association (p < 0.05) between serum and saliva, however, there was no significant association in case of poly-therapy. This is the first report in the Indian population on simultaneous estimation of the three commonly used AEDs, such as CBZ, PHT and PHB in serum and saliva implicating their associations, either in mono-therapy or bi-therapy in PWE.  相似文献   
80.
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