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161.
Aquaculture is important to the United States and the world''s fishery system. Both import and export markets for aquaculture products will expand and increase as research begins to remove physiologic and other animal husbandry barriers. Overfishing of wild stock will necessitate supplementation and replenishment through aquaculture. The aquaculture industry must have a better understanding of the impact of the "shrouded" public and animal health issues: technology ignorance, abuse, and neglect. Cross-pollination and cross-training of public health and aquaculture personnel in the effect of public health, animal health, and environmental health on aquaculture are also needed. Future aquaculture development programs require an integrated Gestalt public health approach to ensure that aquaculture does not cause unacceptable risks to public or environmental health and negate the potential economic and nutritional benefits of aquaculture.  相似文献   
162.
Service system reforms of the past decade have yielded innovations in type, accessibility, and cost of services provided for some children and families with serious problems, but few of the treatments delivered have been empirically evaluated. Rigorous tests of well-conceived treatments are needed to provide a solid foundation for continued reform. Multisystemic therapy has demonstrated efficacy in treating serious clinical problems in adolescents and their multineed families and is an example of the successful blending of rigorous treatment outcome research and service system innovation.  相似文献   
163.
Curative surgery for gastric cancer: Study of 166 consecutive patients   总被引:1,自引:0,他引:1  
From January 1980 to December 1991 we operated on 295 patients with a gastric carcinoma. In 166 cases (56.3%) surgery was performed with curative intent. In 93 patients (56%) a subtotal gastrectomy was performed, and in 73 cases (44%) a total gastrectomy. In all the cases a D-2 type lymphadenectomy was used. The global morbidity rate was 23%, and in-hospital mortality was 3.6%. The morbidity and mortality rates of these two operations were statistically different. Global 5-year survival estimate for the whole series is 61.3%. Univariate and multivariate analysis according to T and N (TNM classification), the number of positive nodes resected, and the relation of positive per resected nodes, revealed statistically different outcomes. This kind of quantitative classification allowed identification of high risk groups irrespective of site of nodal involvement. Tumors classified as intestinal or diffuse type by the Lauren classification had similar survival curves and 5-year survival estimates (p=0.834). By univariate and multivariate analysis this classification did not reveal a prognostic value in this group of patients. In our opinion, tumor penetration and lymph node involvement are at present the most reliable prognostic factors available.
Resumen En el período enero 1980 a diciembre 1991 se operaron 295 pacientes con carcinoma gástrico. En 166 (56.3%), la cirugía fue realizada con intención curativa; en 93 (56%) se realizó gastrectomía subtotal y en 73 (44%) gastrectomía total. En la totalidad de los casos se realizó linfadenectomía D-2. La mortalidad global fue 23% y la mortalidad hospitalaria 3.6%. Las tasas de mortalidad y morbilidad de estas dos operaciones aparecieron significativamente diferentes. La sobrevida global a cinco años estimada para la totalidad de la serie es de 61.3%. Los análisis uni y multivariables de acuerdo con la clasificación TNM, el número de ganglios positivos resecados y la relación positivos/resecados revelaron resultados estadísticamente diferentes. Este tipo de clasificación cuantitativa permitió la identificación de Grupos de alto riesgo independientes del lugar de la invasión ganglionar. Los tumores clasificados como intestinales o difusos (clasificación de Lauren), registraron similares curvas de sobrevida y de sobrevida estimada a cinco años (P=0.834). Mediante el análisis univariable y multivariable esta clasificación no demostró tener valor pronóstico en nuestro Grupo de pacientes. En nuestra opinión, el grado de penetración del tumor y la invasión ganglionar son los factores de pronóstico más confiables.

Résumé Entre Janvier 1980 et Décembre 1991, nous avons opéré 295 patients ayant un cancer gastrique. Chez 166 (56.3%), l'exérèse a été jugée curative. Chez 93 (56%) des cas, il s'agissait d'une gastrectomie subtotale alors que dans 73 (44%) cas, une gastrectomie totale a été pratiquée. Dans tous les cas une lymphadénectomie du type D-2 lui a été associée. La morbidité globale a été de 23% et la mortalité hospitalière de 3.6%. La morbidité et la mortalité des deux types d'intervention différaient de façon statistiquement significative. La survie à 5 ans de la série en entier a été de 61.3%. Une analyse uni et multifactorielle a pu mettre en évidence une différence statistiquement significative en ce qui concerne la survie par rapport à la classification T-N (TNM), le nombre de ganglions réséqués et le nombre de ganglions envahis/nombre de ganglions enlevés. Cette analyse a permis d'identifier les malades à haut risque, indépendamment du site de l'envahissement lymphatique. La courbe de survie et la survie estimée à 5 ans étaient identiques selon que la tumeur a été classée intestinale ou diffuse selon Lauren. Cette classification n'a pas, pourtant, de valeur pronostique d'après les analyses uni et multifactorielle. A notre avis, la pénétration tumorale et le degré d'envahissement lymphatique sont les deux facteurs pronostiques les plus constants.
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164.
165.
The heterogeneity of disease conditions in acute leukemia (AL) requires the most discriminative procedures for a differential diagnostic classification. Selected cases of AL, representative of lineage fidelity, multilineage phenotype and phenotypic switch, are reviewed to document that the diversity of the leukemic cells (lineage involved, maturation stage, aberrant markers), although not always characterizable by morphological differences, is reflected by a variety of immunophenotypes which may be efficiently characterized by flow cytometry to obtain a precise diagnosis.  相似文献   
166.
In widespread informal gold mining in the Amazon Basin, mercury is used to capture the gold particles as amalgam. Releases of mercury to the environment have resulted in the contamination of freshwater fish with methylmercury. In four comparable Amazonian communities, we examined 351 of 420 eligible children between 7 and 12 years of age. In three Tapajós villages with the highest exposures, more than 80% of 246 children had hair-mercury concentrations above 10 microg/g, a limit above which adverse effects on brain development are likely to occur. Neuropsychological tests of motor function, attention, and visuospatial performance showed decrements associated with the hair-mercury concentrations. Especially on the Santa Ana form board and the Stanford-Binet copying tests, similar associations were also apparent in the 105 children from the village with the lowest exposures, where all but two children had hair-mercury concentrations below 10 microg/g. Although average exposure levels may not have changed during recent years, prenatal exposure levels are unknown, and exact dose relationships cannot be generated from this cross-sectional study. However, the current mercury pollution seems sufficiently severe to cause adverse effects on brain development.  相似文献   
167.
A direct sandwich enzyme-linked immunosorbent assay (ELISA), employing affinity purified antivenom antibodies specifically recognizing the homologous venom, was developed for species-specific detection of bothropic venom. The method is based on a two-step affinity purification of the specific antibodies. A species monovalent antivenom is adsorbed onto a venom adsorbent containing heterologous venoms from the Bothrops, Crotalus and Lachesis genera. The species-specific antibodies obtained, are then adsorbed onto a second venom adsorbent containing only the homologous venom for the removal of non antivenom antibodies. Venom concentrations of 0.1 and 1,000 ng/ml were specifically identified for Bothrops jararacussu and B. alternatus venom respectively.  相似文献   
168.
In December 2019, a new viral respiratory infection known as coronavirus disease 2019 (COVID-19) was first diagnosed in the city of Wuhan, China. COVID-19 quickly spread across the world, leading the World Health Organization to declare it a pandemic on March 11, 2020. The disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a similar virus to those involved in other epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Epidemiological studies have shown that COVID-19 frequently affects young adults of reproductive age and that the elderly and patients with chronic disease have high mortality rates. Little is known about the impact of COVID-19 on pregnancy and breastfeeding. Most COVID-19 cases present with mild flu-like symptoms and only require treatment with symptomatic relief medications, whereas other cases with COVID-19 require treatment in an intensive care unit. There is currently no specific effective treatment for COVID-19. A large number of drugs are being used to fight infection by SARS-CoV-2. Experience with this therapeutic arsenal has been gained over the years in the treatment of other viral, autoimmune, parasitic, and bacterial diseases. Importantly, the search for an effective treatment for COVID-19 cannot expose pregnant women infected with SARS-CoV-2 to the potential teratogenic risks of these drugs. Therefore, it is necessary to determine and understand the safety of anti-COVID-19 therapies prior to conception and during pregnancy and breastfeeding.Key words: COVID-19, SARS-CoV-2, antiviral, pregnancy, breastfeeding  相似文献   
169.
Factors influencing contralateral lymph node metastasis from oral carcinoma   总被引:4,自引:0,他引:4  
BACKGROUND: An ipsilateral neck dissection is mandatory during initial treatment stages II-IV oral carcinomas. However, no consensus exists whether or not to perform an elective contralateral neck dissection. METHODS: Five hundred thirteen consecutive cases of squamous cell carcinoma (269 tongue, 135 floor of the mouth, 44 inferior gingiva, 65 retromolar trigone) were reviewed. Tumor stages were: 69 T1, 227 T2, 217 T3-T4, 263 N0, 250 N1-N3. A total of 563 neck dissections were performed in 448 patients. Univariate and multivariate analysis of risk factors were performed using logistic regression. RESULTS: Two hundred twenty-three patients (49.8%) had positive nodes in the specimen (182 ipsilateral, 36 bilateral, 5 contralateral). Contralateral neck recurrences occurred in 38 cases (33 not submitted to a contralateral neck dissection initially). Multivariate logistic regression analysis demonstrated that clinical stage (p = .0001), tumor crossing midline (p = .0011), and floor of the mouth involvement (p = .0236) were the most important predictors of contralateral metastasis. CONCLUSION: The contralateral side of the neck is a common and potentially preventable site of recurrence in tumors of the oral cavity. The multivariate model obtained discriminates patients with low and high risk (more than 20%) of contralateral metastasis. The application of this mathematical model can be useful for the indication of contralateral neck dissections, because not all tumors crossing midline are associated to a high risk (stages I and II tumors not involving the floor of the mouth) and not all tumors not crossing midline are at low risk (stages III and IV tumors involving the floor of the mouth).  相似文献   
170.
Moyamoya is a chronic progressive cerebrovascular disease with characteristic angiographic findings and a clinical picture with episodes of transient ischemic attacks, headache, seizures, hemiparesis, which may resolve after surgical treatment. We describe the case of a girl with the typical findings of the disease, comparing them before and after surgery with the use of neuropsychological tests, neurological examination and laboratory tests.  相似文献   
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