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81.
A case of Takayasu's arteritis resulting in extensive fusiform aneurysmal dilatation of the entire aorta extending from the aortic root to the abdominal bifurcation associated with aortic regurgitation is described. She underwent successful radical replacement of the aortic root, ascending, transverse arch and proximal part of the descending aorta employing simultaneous modified Bentall and Elephant trunk techniques. During aortic arch replacement the brain was protected by selective antegrade innominate perfusion under moderate hypothermia. A pattern to the best of our knowledge, has not been reported earlier.  相似文献   
82.
PURPOSE: In a living related transplantation program it is not always possible to find an ideal donor. Sometimes the only available donor in the family has some benign disease or suboptimal renal anatomy or physiology, or is too old to be accepted and defined as a marginal donor. However, with proper screening the donor pool can be increased by accepting these marginal donors and treating the benign diseases which is beneficial to the donor. We evaluate the outcome of grafts from marginal donors. MATERIALS AND METHODS: From July 1988 to August 1997, 581 live related transplantations were performed. Of the donors 52 were older than 60 years and 34 had associated benign renal or nonrenal anomaly or disease. These donors were accepted after thorough questioning and consultation with family members. The recipients of graft from elderly donors were evaluated for the number of rejections, serum creatinine at last followup and graft survival. RESULTS: Of the recipients 52 received grafts from elderly donors with a mean age of 62.6+/-3.7 years. Mean followup was 34.14+/-0.7 months. The 2 and 5-year actuarial graft survival was 96% and 74%, respectively. Creatinine was normal (less than 1.5) in 37% of recipients and 1.5 to 2.5 mg.% in 46%. The rejection rate in postoperative month 1 was 29%. All donors underwent simultaneous surgery to treat the benign disease, and all did well after surgery. CONCLUSIONS: By accepting these marginal donors a 14.6% increase in the living related donor pool was achieved without compromising recipient or donor safety. Otherwise these recipients would have been forced to undergo unrelated transplantation or be maintained on dialysis, which is particularly difficult in a developing country. Donors with associated disease benefited from cure.  相似文献   
83.
Objective: To compare transvaginal sonography (TVS), sonohysterography (SHG), hysteroscopy and endometrial aspiration (EA) and p53 expression in assessing endometrial abnormalities in women on tamoxifen. Methods: In a cross sectional study of 50 pre- and post-menopausal women receiving tamoxifen for > 2 years, all participants underwent TVS and EA. Those with endometrial thickness > 4 mm on TVS underwent hysteroscopy and SHG. Serum p53 antibody and p53 immunohistochemistry were tested in all women. Results: The sensitivity and specificity when compared with histopathology as the reference standard were as follows: TVS 100% and 33.3%, SHG 85.7% and 50%, hysteroscopy 92.8% and 80.8%, serum p53 50% and 83.3%, and p53 immunohistochemistry 57.1% and 61.1%. Prevalence of endometrial abnormalities was not significantly different in asymptomatic and symptomatic women. Conclusion: Tamoxifen-users require routine testing for endometrial evaluation. TVS followed by hysteroscopy and biopsy is an effective option. p53 expression correlates with histological abnormalities. Key words: Tamoxifen, Sonography, Sonohysterography, Hysteroscopy, Endometrium, p53.  相似文献   
84.
Several 1-(substituted phenoxy)-3-{[4-(4-trifluoromethyl) phenoxy] piperidin-1-yl} propan-2-ols (str.II) were prepared in a six-step reaction sequence starting from methylamine and ethyl acrylate and evaluated for antidepressant activity. The compounds were fully characterized by spectral and elemental analyses, and were tested for their effect on gross behavior, antireserpine and anorexigenic activity. No effect was observed on gross behavior and some of them showed fluoxetine like antireserpine and anorexigenic activity.  相似文献   
85.
Activation of cell surface death receptors by their cognate ligands triggers apoptosis. Several human death receptors (Fas, TNF-R1, TRAMP, DR4, DR5, DR6, EDA-R and NGF-R) have been identified. The most promising cytokine for anticancer therapy is TRAIL/APO-2L, which induces apoptosis in cancer cells by binding to death receptors TRAIL-R1/DR4 and TRAIL-R2/DR5. The cytotoxic activity of TRAIL is relatively selective to cancer cells compared to normal cells. Signaling by TRAIL and its receptors is tightly regulated process essential for key physiological functions in a variety of organs, as well as the maintenance of immune homeostasis. Despite early promising results, recent studies have identified several TRAIL-resistant cancer cells of various origins. Based on molecular analysis of death-receptor signaling pathways several new approaches have been developed to increase the efficacy of TRAIL. Resistance of cancer cells to TRAIL appears to occur through the modulation of various molecular targets. They may include differential expression of death receptors, constitutively active Akt and NFkappaB, overexpression of cFLIP and IAPs, mutations in Bax and Bak genes, and defects in the release of mitochondrial proteins in resistant cells. Conventional chemotherapeutic and chemopreventive drugs, and irradiation can sensitize TRAIL-resistant cells to undergo apoptosis. Thus, these agents enhance the therapeutic potential of TRAIL in TRAIL-sensitive cells and sensitize TRAIL-resistant cells. TRAIL and TRAIL-receptor antibodies may prove to be useful for cancer therapy, either alone or in association with conventional approaches such as chemotherapy or radiation therapy. This review discusses intracellular mechanisms of TRAIL resistance and various approaches that can be taken to sensitize TRAIL-resistant cancer cells.  相似文献   
86.
The nitrogen-bearing heterocycle pyridine in its several analogous forms occupies an important position as a precious source of clinically useful agents in the field of medicinal chemistry research. This privileged scaffold has been consistently incorporated in a diverse range of drug candidates approved by the FDA (Food and Drug Administration). This moiety has attracted increasing attention from several disease states owing to its ease of parallelization and testing potential pertaining to the chemical space. In the next few years, a larger share of novel pyridine-based drug candidates is expected. This review unifies the current advances in novel pyridine-based molecular frameworks and their unique clinical relevance as reported over the last two decades. It highlights an inclination to the use of pyridine-based molecules in drug crafting and the subsequent emergence of several potent and eligible candidates against a range of diversified diseases.

The nitrogen-bearing heterocycle pyridine in its several analogous forms occupies an important position as a precious source of clinically useful agents in the field of medicinal chemistry research.  相似文献   
87.
The involvement of testosterone in di(2-ethylhexyl)phthalate (DEHP) induced testicular injury has been examined by coadministration of testosterone (1 mg/kg) along with DEHP (2000 mg/kg) daily for 15 days. The coadministration of testosterone and DEHP appears to have prevented the testicular injury as judged by the biochemical and histopathological changes. The sperm count and the activity of the testicular enzymes, gamma-glutamyl transpeptidase (GGT), lactate dehydrogenase (LDH), sorbitol dehydrogenase (SDH), beta-glucuronidase and acid phosphatase, related with the maturation of sperm, which were significantly altered by DEHP treatment were found to be within normal levels after the combination treatment of DEHP and testosterone. The histopathological studies also showed more or less normal spermatogenic events. The results of this study have suggested the involvement of testosterone in DEHP induced testicular atrophy.  相似文献   
88.
PURPOSE: To propose a novel concept that progesterone receptor antagonists, e.g., mifepristone, may prove effective in treating a variety of cancers--even those not shown to be hormonally dependent or possessing progesterone receptors. METHODS: Multiple human leukemia cell lines were evaluated for mRNA expression of an immunomodulatory protein called the progesterone-induced blocking factor (PIBF) that suppresses natural killer (NK) cell activity during normal pregnancy. Furthermore, we evaluated the effects of progesterone (P) and mifepristone in PIBF protein expression. Finally, the effect of mifepristone treatment of mice with advanced leukemia was evaluated. RESULTS: All tumor cell lines evaluated were found to express mRNA for PIBF and some were found to even express the PIBF protein. The addition of P to the media increased the expression of PIBF and mifepristone downregulated its expression. Treatment of mice with spontaneous leukemia when they already had extensive disease seemed to increase the length and quality of their life. CONCLUSIONS: These data and other experience with mice with lung cancer and some anecdotal human cancer experience suggest that various cancers may utilize similar mechanisms used by the fetus to escape NK cell surveillance. Mifepristone and other progesterone receptor antagonists may deserve a clinical trial in human cancer even where there is no knowledge of the presence of progesterone receptors.  相似文献   
89.
90.
Objective Ogilvies syndrome (OS) is a rare condition in obstetrics but occurs most commonly after caesarean section. Mortality rates from OS can be as high as 36–50% when bowel perforation or ischemia develops which highlights the early recognition of this condition. Early diagnosis is therefore essential to prevent serious morbidity and mortality. Conclusion We, therefore report a case of OS after caesarean section in which early detection by senior clinicians resulted in successful management of the condition and an excellent outcome.  相似文献   
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