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排序方式: 共有4015条查询结果,搜索用时 11 毫秒
91.
Chelaïfa K Bouzaïdi K Ben Ghorbel I Azaiez O Menif E Ben Messaoud M Turki I Houman H Miled M Slim R 《La Tunisie médicale》2003,81(4):273-276
Pituitary-hypothalamic axis Langerhans cell histiocytosis is an uncommon entity. It is a rare disease in adults. The CT and MR study provides us the best anatomo-topographic evaluation and determine the precise size of the lesion which are necessary to the treatment. We report a case of hypothalamic involvement by Langerhans cell histiocytosis accompanied by lesions in bone affecting a 31-year-old woman. The clinical, histiotological and CT/MR findings of histiocytosis X are described in this article. 相似文献
92.
93.
Macari GS Kassim RA Yoon P Saleh KJ 《Journal of the Southern Orthopaedic Association》2003,12(2):83-89
Despite the success of Sir John Charnley's cemented total hip arthroplasty (THA), large numbers of patients demonstrated mechanical failure due to loosening. The two main initial concerns were infection and wear. With the recent advances in antibiotics and aseptic techniques and with improvement in surgical technique, the incidence of infection has decreased tremendously. Subsequently, the issues of wear and osteolysis have become the main concern. Initially attributing these problems to so-called "cement disease," clinicians sought out alternative methods of fixation; hence arose cementless femoral stem fixation. This article provides an overview of our modern understanding of cementless femoral stem fixation, focusing on design issues and outcomes. Particular attention is paid to three areas of continuing controversy with regard to the uncemented femoral stem: geometric design, material composition, and type and extent of porous coating. 相似文献
94.
Alterations of the p53 tumor suppressor gene are the most common genetic changes detected in human cancers as well as in papillary and invasive bladder cancer. Several studies have demonstrated an association between HPV infection and urological malignancies. In the present work, the p53 gene status was studied together with the frequency of HPV in 99 cases of Bilharzial bladder cancer [BBC] in Egypt and both were correlated to the clinicopathological features of the patients. SSCP and sequencing were used to screen the p53 gene for mutations at exons 4-10 and IHC was performed to detect protein overexpression. PCR was used for detection and typing of HPV-DNA in tumor samples. p53 mutations were detected in 33.3% of the studied cases whereas protein overexpression was detected in 35.6% of the cases. The highest concordance rate was observed in cases harboring mutations at exon 4 [87.5%]. Bilharzial infestation was obvious in 72.2% of the cases that showed mutations. Exon 8 showed the highest rate of mutation [32%] followed by exons 4 and 5 [22% each]. The commonest mutational event was G:C transversion [15/50] especially at CpG dinucleotides. A mutational hot spot was detected at exon 4, codons 72-73. HPV-DNA was detected in 48.97% of the cases the majority of which [64.6%] were of type 16. Significant correlation was found between p53 mutation and the pathological stage as well as p53 overexpression and tumor grade. Our results demonstrate that the mutational spectrum in BBC is different from that of bladder cancer in Western countries in many aspects and suggest an etiological role of HPV in this type of neoplasm. However, both HPV infection and p53 gene abnormalities may contribute to Bilharzial bladder carcinogenesis in an independent way. 相似文献
95.
Esterberg J Kassim RA Redmon J Coad J Macari GS Saleh KJ 《American journal of orthopedics (Belle Mead, N.J.)》2003,32(9):455-458
Hypophosphatemic rickets, a rare metabolic bone disease, presents mainly in children but has also been reported in several adults. In this report, we describe the case of a man presenting with hip pain and weakness, both of several months' duration, and tested for hypophosphatemic rickets. The patient was eventually referred to a tertiary-care center, where he was diagnosed with bilateral subtrochanteric femoral stress fractures and severe osteopenia secondary to hypophosphatemic osteomalacia. The patient was treated with closed reduction and internal fixation and vitamin D and phosphorus. Outcomes were good at 7-month follow-up. 相似文献
96.
el-Said KF el-Sharkawy MF Abdel-Hamid HA 《The Journal of the Egyptian Public Health Association》2003,78(1-2):95-111
The bread-making industry involves a combination of hazardous exposures. A biochemical and environmental study was conducted on manual and semi-automatic bakeries. The aim of this study was to investigate different biochemical changes and environmental factors among bakery workers. Blood samples were collected from 25 exposed workers and 25 age and sex matched control subjects, determination of circulating IgE (immunoglobulin E), carbonic anhydrase and catalase enzyme were analyzed in the blood Environmental measurements (respirable dust, total suspended particulate TSP). Heat stress, noise and relative humidity were analyzed in manual and semi automatic bakeries. A significant increase in the level of IgE catalase and carbonic anhydrase were significantly higher among exposed workers in comparison with control group either in manual and semi-automatic bakeries Environmental factors were significantly higher especially in manual bakeries Where higher contaminates and heat stress exposure than automatic ones due to nature of work type of fuel. age of oven etc and most of contaminants exceeded the TLV Attention should be paid to the health of the bakery workers and it has been recommended to completely mechanize manual bakeries. 相似文献
97.
Several substances used in rubber processing are known to be of genotoxins and haematotoxins. Such as benzene, phenols, amines amides, naphthalene and benzo(a)pyrene. Twenty-five exposed workers from a rubber factory were compared with twenty-five controls working as administrative staff in the same factory. An elevated level of urinary thioether (mercapturic acid derivatives) a significant elevation in the level of DNA SSB was found among exposed workers in comparison with control group (p < 0.01). A significant increase in the absolute numbers of peripheral leukocytes and in erthrocyte mean cell volume was observed among exposed workers in comparison with controls (p < 0.01), while a significant decrease in the percentage of lymphocytes and eosinophils was found among exposed workers in comparison with controls. However, the percentage of monocytes was not altered. The reported results have justified the use of genotoxic biomarkers in assessing levels of genotoxic exposure in human population groups and as a screening biomarkers in periodic medical examination as a protective measure. 相似文献
98.
Quantifying the extent of femoral head involvement in osteonecrosis 总被引:10,自引:0,他引:10
Cherian SF Laorr A Saleh KJ Kuskowski MA Bailey RF Cheng EY 《The Journal of bone and joint surgery. American volume》2003,(2):309-315
BACKGROUND: There are numerous methods for quantifying the extent of osteonecrosis of the femoral head. However, there is no consensus regarding which method is the most reliable. The purpose of this study was to determine the reliability and prognostic accuracy of three commonly used methods for quantifying the extent of osteonecrosis of the femoral head. METHODS: Thirty-nine hips in twenty-five patients who had stage-I or II osteonecrosis of the femoral head, according to the grading system of the Association Research Circulation Osseous, were independently examined on two separate occasions by three observers of different specialty backgrounds and experience. Each observer used three methods to quantify the extent of osteonecrosis of the femoral head: (1) the index of necrotic extent, (2) the modified index of necrotic extent, and (3) the percentage of femoral head involvement. The interobserver and intraobserver agreement was determined for each method, and the ability of each method to predict the time to subchondral collapse was analyzed statistically. RESULTS: There was significantly valid agreement among the observers for all three methods (p < 0.001 for all three). The correlation coefficients demonstrated substantial agreement among raters when they measured the index of necrotic extent and the percent involvement and nearly perfect agreement when they measured the modified index of necrotic extent. Survivorship analysis revealed that the percent involvement (p < 0.05), index of necrotic extent (p < 0.007), and modified index of necrotic extent (p < 0.04) were prognostically significant predictors of subchondral fracture. CONCLUSIONS: Our results indicate that the index of necrotic extent, modified index of necrotic extent, and estimation of the percentage of involvement of the femoral head are reproducible and reliable methods for quantitatively evaluating the extent of osteonecrosis of the femoral head. We believe that the three methods can be utilized with confidence. Furthermore, they are clinically useful for identifying hips at greatest risk for subchondral collapse. 相似文献
99.
Premenstrual syndrome (PMS) and the perimenopause are each difficult conditions to manage. When they co-exist the difficulty is more than doubled. Understanding and recognising the differences and the similarities between these conditions should enable clinicians to provide appropriate treatment and significantly improve women's quality of life. Distinction between the two can be difficult. Anecdotally women seem more prone to PMS symptoms during the perimenopause, or at least they tolerate the symptoms less well. Symptoms of the perimenopause arise from falling oestrogen levels with irregular ovulation, resulting in symptoms of oestrogen lack and heavy irregular periods. Symptoms of the perimenopause are thus relieved by the administration of oestrogen. Premenstrual syndrome frequently results when ovulation occurs. PMS appears to be due directly to the progesterone produced following ovulation in women who have enhanced sensitivity to this steroid. Treatment can thus be achieved by suppressing ovulation or reducing progesterone sensitivity; the latter seems achievable by the administration of selective serotonin re-uptake inhibitors. Ovulation can be suppressed by a variety of methods and oestrogen is an approach which is frequently employed. This will also effectively treat menopausal symptoms. The main problem with using oestrogen is that a progestogen must be administered to prevent endometrial neoplasia; this can result in a return of the PMS symptoms. This article reviews the difficulties encountered in women with both disorders and provides a suggested management strategy. 相似文献
100.
The effectiveness of GnRHa with and without 'add-back' therapy in treating premenstrual syndrome: a meta analysis 总被引:2,自引:0,他引:2
Wyatt KM Dimmock PW Ismail KM Jones PW O'Brien PM 《BJOG : an international journal of obstetrics and gynaecology》2004,111(6):585-593
OBJECTIVE: To determine the effectiveness of gonadotrophin-releasing hormone analogues (GnRHa) with and without hormonal add-back therapy in the management of premenstrual syndrome. DESIGN: Randomised controlled trials were identified by searching multiple databases. SETTING: Exeter and North Devon Research and Development Support Unit and Keele University Academic Unit of Obstetrics and Gynaecology. POPULATION: Women with pre-diagnosed premenstrual syndrome and/or premenstrual dysphoric disorder. METHODS: A meta-analysis of published randomised placebo-controlled trials assessing the use of GnRHa in the management of premenstrual syndrome. The standardised mean difference for each individual study and subsequently an overall standardised mean difference were calculated after demonstrating the consistency or homogeneity of the study results. MAIN OUTCOME MEASURES: Overall improvement in premenstrual symptomatology and effectiveness of GnRHa with additional hormonal add-back therapy were the main outcome measures assessed in this analysis. A secondary analysis was performed to assess the effectiveness of GnRHa in treating physical and emotional symptoms. RESULTS: Overall standardised mean difference for all trials that assessed the efficacy of GnRHa was -1.19 (95% confidence interval [CI] -1.88 to -0.51). The equivalent odds ratio was 8.66 (95% CI 2.52 to 30.26) in favour of GnRHa. GnRHa were more efficacious for physical than behavioural symptoms, although the difference was not statistically significant. The addition of hormonal add-back therapy to GnRHa did not appear to reduce the efficacy of GnRHa alone; standardised mean difference 0.12 (95% CI -0.35 to 0.58). CONCLUSIONS: GnRHa appear to be an effective treatment in the management of premenstrual syndrome. The addition of hormonal add-back therapy to reduce side effects does not reduce efficacy. 相似文献