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991.
Chemotherapy may cause oral ulceration but a thorough investigation of symptoms and signs is important to determine the underlying diagnosis accurately. We describe a case of a patient with a poorly differentiated urothelial carcinoma of the bladder developing a tongue metastasis. This is a challenging diagnosis to make given the rarity of the presentation but it illustrates the need to evaluate any new symptoms fully.  相似文献   
992.
A laparoscopic approach is being used increasingly in specialist centres for the resection of hepatocellular carcinomas and compares favourably with the traditional open approach, in terms of perioperative morbidity and mortality as well as long-term survival. We present a case of port site recurrence in a patient who underwent a laparoscopic left lateral segmentectomy for a hepatocellular carcinoma diagnosed during investigation of symptomatic gallstones. Nearly three years following surgery, surveillance computed tomography demonstrated a suspicious lesion at the site of one of the laparoscopic ports. Further resection was carried out and the lesion was confirmed histologically to be an isolated recurrence of the primary hepatocellular carcinoma, involving peritoneum and adominal wall. This case demonstrates that it is possible to encounter port site metastasis following laparoscopic resection of primary liver tumours although the incidence is very rare.  相似文献   
993.
Several plastic materials used in blood storage were evaluated for their ability to transmit ultraviolet B (UVB) light. A plastic bag manufactured from sheets of transparent Teflon efficiently (78-86%) transmitted UVB light and was employed in subsequent functional studies of lymphocytes and platelets exposed to UVB light while contained in these bags. In vitro experiments showed a UVB dose-dependent abrogation of lymphocyte responder and stimulator functions, with concurrent preservation of platelet aggregation responses. In a phase I pilot study, UVB-treated platelet concentrates were administered to four bone marrow transplant recipients. Adverse effects attributable to the transfusions were not observed, and patients showed clinically effective transfusion responses. No patient developed lymphocytotoxic HLA or platelet antibodies. These studies suggest that platelets can be effectively irradiated with UVB light in a closed system. However, numerous variables, including container material, volume and composition of contents, steady exposure versus agitation, and exact UV wavelength, must be considered.  相似文献   
994.
Fc fragments derived from human and murine Ig were found to be potent adjuvants when administered with antigen. Both the in vivo and in vitro anti- sheep erythrocytes (SRBC) responses were significantly enhanced by Fc fragments. The adjuvant effect was shown to be extremely dependent upon the dose of antigen used, with the greatest enhancement occurring when suboptimal doses of antigen are employed. The anti-genicity of the Fc molecule was not related to its adjuvanticity because homologous Fc was as potent an adjuvant as heterologous Fc. Moreover, human Fc fragments enhanced anti-SRBC responses in mice which were tolerant to human gamma globulin.  相似文献   
995.

Background

The epidemiology of Hirschsprung's disease (HSCR) in Bangladesh has never been studied. The aim of this study was to determine the epidemiological characteristics of HSCR in Bangladesh.

Methods

Data from fifty patients were collected prospectively from two hospitals in Chittagong, Bangladesh.

Results

The rate of consanguinity (16%) among parents of HSCR patients was higher than that of the general population (10%). Maternal age at the time of birth of the affected child was ≤ 30 years in all cases except one. No association was found between parents' occupation and HSCR. No patient was born preterm and only three patients (6%) had low birth weight. Nine patients (18%) had associated anomalies. We found coexistence of bilateral accessory tragi and ankyloglossia in one patient, and coexistence of rectal duplication cyst in another. Neither anomaly had been previously reported in HSCR patients.

Conclusions

Our study suggests that consanguinity might increase the risk of HSCR whereas advanced maternal age does not. HSCR patients were found more likely to born at term and with normal birth weight. The coexistence of HSCR with previously unreported anomalies highlights the diversity of conditions that can co-occur with HSCR.

Levels of evidence

IV  相似文献   
996.
ObjectiveSupplemental MRI screening for women at high risk for breast cancer is underutilized. Our study assessed how primary care providers in our healthcare network identify high-risk women and recommend high-risk screening breast MRI.MethodsAn electronic survey was distributed to providers in OB/GYN, family, and internal medicine departments between 1/14/19 and 3/22/19. The survey inquired about methods used to assess breast cancer risk, familiarity with the American Cancer Society's definition of high-risk, and whether screening breast MRI is recommended for high-risk women.ResultsResponse rate was 17% (89/524). After excluding providers who ordered ≤10 mammograms per year, the study included 75 respondents, who mostly ordered 10-1000 mammograms per year and supported annual/biennial screening mammogram starting at age 40-50 years. More providers reported estimating breast cancer risk qualitatively (with family, clinical history, and/or breast density) than quantitatively with risk calculators (73/75, 97% vs 22/75, 29%). A minority of providers (23/75, 31%) correctly defined high lifetime risk. Only 9/75 (12%) providers recommended screening MRI for high-risk women. Use of quantitative risk calculators or ability to correctly define high-risk were not associated with likelihood of recommending MRI screening. More providers had recommended MRI for screening in the setting of dense breasts than for high-risk screening (23/75, 31% vs 9/75, 12%).ConclusionPrimary care providers at our institution did not routinely recommend screening MRI for high-risk women. Risk assessment and reporting at the time of mammography may improve MRI utilization and is an opportunity for radiologists to add value and directly participate in patient-centered care.  相似文献   
997.
998.
Coronavirus disease 2019 is a pandemic disease caused by a novel RNA coronavirus, SARS coronavirus 2 (SARS-CoV-2), which is implicated in the respiratory system. SARS-CoV-2 also targets extrapulmonary systems, including the gastrointestinal tract, liver, central nervous system and others. SARS-CoV-2, like other RNA viruses, targets the liver and produces liver injury. This literature review showed that SARS-CoV-2-induced liver injury is different from other RNA viruses by a transient elevation of hepatic enzymes and does not progress to liver fibrosis or other unfavorable events. Moreover, SARS-CoV-2-induced liver injury usually occurs in the presence of risk factors, such as nonalcoholic liver fatty disease. This review highlights the important differences between RNA viruses inducing liver injury taking into consideration the clinical, biochemical, histopathological, postmortem findings and the chronicity of liver injury that ultimately leads to liver fibrosis and hepatocellular carcinoma.  相似文献   
999.
1000.

Background

Leishmaniases are a group of diseases caused by Leishmania parasites. Growing of drug unresponsiveness in leishmaniasis patients necessitates the development of new drugs and accordingly a suitable assay is needed for evaluation of any modalities. The aim of this study was to compare four drug assays methods, agar dilution, broth dilution, cylinder plate and disk diffusion, for evaluation of anti-leishmanial drugs on Leishmania promastigotes, using glucantime as a currently available drug for treatment of leishmaniasis.

Methods

For broth dilution method, different concentration of glucantime was added to the parasite culture (promastigotes of Leishmania), while in cylinder plate method wells were punched in agar gel and filled with different concentration of drug and zone of inhibition was measured in each well. In disk diffusion method, the parasites were cultivated on the surface of agar; filter paper disks were enriched with various concentration of glucantime and were placed on the surface of agar. In agar dilution method, various concentrations of drug were incorporated onto blood agar and the parasites were cultivated on the surface of the agar.

Results

A direct correlation was found between the drug concentration and size of inhibitory zones in cylinder plate and disk diffusion methods. These two drug assays methods provided much better performance in comparison with broth and agar dilution methods.

Conclusion

Cylinder plate and disk diffusion methods seem to be acceptable methods for susceptibility testing of anti-leishmanial compounds on Leishmania promastigotes.  相似文献   
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