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111.
112.
The farnesyl transferase inhibitor (FTI) SCH66336 has been shown to have antitumor activities in head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. However, its mechanism of action has not been well defined. Here, we report that the insulin-like growth factor (IGF) binding protein (IGFBP)-3 mediates antitumor activities of SCH66336 in HNSCC by inhibiting angiogenesis. SCH66336 significantly suppressed HNSCC tumor growth and angiogenesis via mechanisms that are independent of H-Ras and RhoB. By inducing IGFBP-3 secretion from HNSCC cells, this compound suppresses angiogenic activities of endothelial cells, including vessel formation in chorioallantoic membranes of chick, endothelial cell sprouting from chick aorta, and capillary tube formation of human umbilical vascular endothelial cells (HUVEC). Knockdown of IGFBP-3 expression in HNSCC cells by RNA interference or depletion of IGFBP-3 in HUVECs by neutralizing antibody effectively blocked the effects of IGFBP-3 secreted from SCH66336-treated HNSCC cells on HUVECs. These findings suggest that IGFBP-3 could be a primary target for antitumor activities of FTIs and that IGFBP-3 is an effective therapeutic approach against angiogenesis in HNSCC.  相似文献   
113.
PURPOSE: Alteration of the FAS/FAS ligand (FASLG) pathway regulating cell death may lead to cancer development, but the effects of functional promoter polymorphisms of the FAS and FASLG genes on risk of squamous cell carcinoma of the head and neck (SCCHN) are unknown. DESIGN: We genotyped the FAS -1377 G>A, FAS -670 A>G, FASLG -844 C>T, and FASLG IVS2nt -124 A>G polymorphisms in 721 case patients with SCCHN and 1,234 cancer-free non-Hispanic White control subjects frequency-matched by age and sex. Multivariate logistic regression was used to assess the adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Compared with the FAS -1377 GG and -670 AA genotypes, the FAS -1377 AA and -670 (GG+AG) genotypes were associated with an increased risk of SCCHN (OR, 2.23; 95% CI, 1.07-4.64 and OR, 1.24; 95% CI, 1.01-1.52, respectively), whereas no risk of SCCHN was associated with any of the FASLG genotypes. When we used the combined FAS -1377 (GG+AG)/-670 AA genotypes as the reference, we found that the individuals carrying the FAS -1377 AA/-670 (GG+AG) had the highest risk (OR, 2.69; 95% CI, 1.24-5.83), whereas individuals carrying genotypes other than FAS -1377 (GG+AG)/-670 AA had a higher risk of SCCHN (OR, 1.24; 95% CI, 1.01-1.52). Furthermore, the elevated risk was particularly evident for pharyngeal cancer with the larger tumors without regional lymph metastasis (OR, 1.77; 95% CI, 1.07-2.94). CONCLUSIONS: The FAS (but not FASLG) polymorphisms seem to contribute to risk of developing SCCHN, particularly the pharyngeal cancer in non-Hispanic Whites. However, potential selection bias warrants future population-based studies to verify the findings.  相似文献   
114.
Summary: This paper describes factors associated with singleton stillbirths weighing 2,500 g or more, born in 1987 and reported to the NSW Midwives' Data Collection (MDC), a statewide perinatal data collection system. A total of 136 singleton stillbirths in this weight range were notified to the MDC, representing one-quarter of all singleton stillbirths in NSW. MDC records on these stillbirths were linked with perinatal death registrations for 125 of the 136. The death registrations indicated that fetal death occurred during labour in 20 cases, prior to the onset of labour in 98, and at an unknown time in the remaining 7 cases. Placental complications, including haemorrhage and functional abnormalities of the placenta, were the most frequent group of conditions associated with the stillbirths, being recorded as the underlying cause of death in 42 (34%) of the 125 cases. Cord complications (such as cord compression or cord around the neck) were given as the underlying cause of death in 30 cases (24%). The death certificate diagnosis was confirmed by autopsy in only 27 of the 125 cases (22%), although autopsies may have been done on a further 45 cases (36%). An adequate explanation of the cause appeared to be lacking for many of the fetal deaths. This highlights the importance of a thorough and systematic investigation of stillbirths. A list of standard investigations to be carried out following a stillbirth is proposed.  相似文献   
115.
Summary: Two different screening methods, the Papanicolaou (Pap) smear and cervigram were compared in screening 245 Sydney women over a 6-month period in 1988 at a city sexually transmitted diseases (STD) centre, for cervical human papillomavirus (HPV), cervical intraepithelial neoplasia (CIN) and cervical cancer. The Pap smear through the identification of cytologically abnormal cells correctly detected 54% of cases of histologically proven CIN and 39.2% of cases of HPV. The cervigram through the identification of acetowhite epithelium and/or abnormal vessels on the cervix correctly detected 64% of cases of histologically proven CIN and 70.6% of cases of HPV. However, when both tests were used together, 92% of CIN lesions and 82.4% of HPV lesions were correctly identified. Histology of a colposcopically directed biopsy was used as the 'gold standard'. The sensitivity and specificity of the Pap smear after correction for verification bias was 46% and 78% respectively, and for the cervigram was 49% and 60% respectively. Hence neither screening test appears adequate on its own, at least in an STD population.  相似文献   
116.
Galectins are a family of non-integrin beta-galactosidase-binding lectins. Altered expression of galectins has been associated with neoplastic transformation and progression in several human tumors. In this study, we examined the distribution patterns of galectin-1 and galectin-3 in normal (n=45), benign (n=16), and malignant (n=49) salivary gland specimens using immunohistochemistry to determine their diagnostic and/or biological implications in salivary gland tumorigenesis. In normal salivary glands, galectin-3 expression was limited to ductal cells, and galectin-1 was usually faintly detected in ductal cells and strongly positive in myoepithelial cells. In benign tumors, galectin-3 maintained the ductal localization, but galectin-1 showed variable expression in ductal and myoepithelial cells. In malignant tumors, most of the polymorphous low-grade adenocarcinomas and carcinoma ex-pleomorphic adenomas expressed both galectins, whereas adenoid cystic and acinic cell carcinomas showed dramatically reduced galectin-3 expression and heterogeneous galactin-1 staining. Our data demonstrated altered localization and expression of galectin-3, and to lesser extent, galectin-1 in salivary gland carcinomas. These findings may assist in the differential diagnosis of some salivary gland malignancies, especially when using small and limited fine-needle aspiration materials.  相似文献   
117.
118.
Treatments designed to relieve paradoxical contraction of the anal sphincters during defecation (anismus) have had limited success in children with encopresis. This has raised doubts as to the clinical relevance of this diagnosis in childhood as anorectal dysfunction. Our aim was to determine whether, in patients who had treatment-resistant encopresis, the presence of electromyographic anismus was associated with increased faecal retention. Sixty-eight children with soiling (mean age 8.7 ± 2.06 years) were assessed by clinical examination, abdominal radiography and then with anorectal manometry. Patients with electromyographic anismus (n= 32; 47%) had significantly increased radiographic rectal faecal retention and were significantly less likely to be able to defecate water-filled balloons. There were no significant differences in response to prior therapy, history of primary encopresis, behavioural adjustment or in sociodemographic data. Our results suggest that electromyographic anismus is associated with obstructed defecation and faecal retention.  相似文献   
119.
BACKGROUND: In neoplastic head and neck lesions, it has been found that the loss or reduction in E-cadherin expression is a late event and is associated with invasion. Low p27 levels have been associated with a poor prognosis in many different tumors, including laryngeal carcinoma. The authors investigated p27 and E-cadherin protein expression in the early stages of head and neck tumorigenesis and evaluated their predictive roles individually and in association with carcinogenesis. METHODS: Tissue biopsies from 46 patients who were participants in 3 chemoprevention trials were analyzed for E-cadherin expression, and 40 samples were analyzed for p27 expression using immunohistochemistry. RESULTS: The data suggested that loss of both E-cadherin expression and p27 expression occurred early during the preneoplastic steps of head and neck carcinogenesis, and loss of p27 protein expression alone (P=0.02) and in combination with loss of E-cadherin expression (P=0.04) was a significant predictor of the risk for head and neck carcinoma. CONCLUSIONS: The loss of p27 expression may be useful in the construction of a risk model for head and neck carcinogenesis and may represent a potential target for chemopreventive interventions. Longer follow-up of the high percentage of low-risk preneoplastic lesions in the current study and validation in a larger sample size may be required to establish the predictive role of these abnormalities.  相似文献   
120.

Background

The sudden increase in incidence and magnitude of mine blast injuries prompted us to highlight the problem and its management.

Methods

The cases of mine blast injuries occurring during mining and demining in a particular geographical area were analysed. Total 27 cases of mine blast injuries occurred during mining or demining operations in a period of 13 months.

Results

Various body regions were involved in the mine blast injuries but the main brunt was borne by feet and legs followed by multiple body regions due to splinters. 14 patients underwent below knee (BK) amputation while 4 patients required through knee (TK) amputations. The effect of blast was so severe that most of the cases required 2 to 5 times wound debridements. The initial aggressive debridement / open stump amputation saved the limb and life of all patients.

Conclusion

A mine blast causes extensive injuries and psychological trauma. Management is needed urgently, surgery is difficult, and amputation is often inevitable. Maximum lives and limbs can be saved with aggressive debridement, repeated inspections and dressings under anaesthesia and definitive closure at optimum time.Key Words: Amputation, Antipersonnel mine, Crush syndrome, Debridements, Mine blast injury, Secondary missiles, Shrapenels  相似文献   
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