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排序方式: 共有3310条查询结果,搜索用时 15 毫秒
31.
Marinovich M Guizzetti M Grazi E Trombetta G Galli CL 《Environmental toxicology and pharmacology》1996,1(1):13-20
The toxin triphenyl tin (TPT), Sn(C(6)H(5))(+)(3) caused a rapid decrease in the F-actin content of promyelocytic human leukemia cells (HL-60) chemically differentiated to neutrophils. Prior incubation (2 min) of the cells with 10 μM TPT did not modify the extent of actin polymerization inducible either by a receptor-mediated stimulus (chemotactic peptide fMLP) or by a direct activator of G proteins (AlF(-)(4)). The inorganic tin salts SnCl(2) and SnCl(4) did not affect F-actin content or production of HL-60 cells. Microfilament thiol groups were not reduced by exposure of cells to TPT, but even increased. When F-actin was exposed to 10 |GmM triphenyltin in a cell-free system, the depolymerizing effect was not detectable. Thus, TPT does not affect cytoskeletal protein directly but depends for its toxicity on some other induced change, probably ionic/osmotic in the intact cell. 相似文献
32.
33.
Emanuela Masini R. Fantozzi P. Blandina A. Galli Tatiana Bani-Sacchi A. Giotti Lucilla Zilletti P. F. Mannaioni 《Naunyn-Schmiedeberg's archives of pharmacology》1982,321(3):171-176
Summary The correlation between the binding of a -adrenoceptor antagonist, (–)[3H]-dihydroalprenolol (DHAP), and the adrenergic inhibition of histamine release by acetylcholine and by compound 48/80 was studied with isolated purified rat mast cells and in rat mast cell crude membrane fractions.Acetylcholine-evoked histamine release was inhibited by catecholamines, in the order isoprenaline > adrenaline > noradrenaline. Pretreatment of cells with (–)alprenolol antagonized the inhibitory effect of isoprenaline on acetylcholine-induced histamine release.40/80-evoked histamine release was bocked by isoprenaline at significantly higher concentrations than those required to inhibit cholinergic histamine release. The inhibitory effect of isoprenaline was equally antagonized by preincubating mast cells with (–)alprenolol.Specific binding sites for DHAP have been demonstrated in rat mast cell membranes. The specific binding of DHAP was inhibited by adrenoceptor agonists and antagonists according to the stereospecificity of these compounds.A close correlation between the binding-inhibitory potency of various adrenergic compounds and the data obtained in the pharmacological experiments was found, thus indicating the presence of -adrenoceptors in rat mast cells. 相似文献
34.
G Galli G Ausili-Cefaro M Salvatori C L Maini V Ciarniello F Spremberg 《La Radiologia medica》1982,68(10):753-757
The authors have reviewed their experiences in determining the presence of liver metastases in 103 patients by radiocolloid scanning. The sensitivity of liver scanning proved to be quite low if the presence of focal defects of tracer's distribution was chosen as the diagnostic criterion. The inclusion of less restrictive criteria, such as liver enlargement or irregular distribution of the tracer, resulted in an higher sensitivity without lowering the predictive value of a negative scan. Using the more extensive diagnostic criterion, sensitivity, specificity and accuracy were in the range of 90%. Abnormal liver scans are common in patients classified as T3-T4 or N+ and their chances of to be "true positives" are high. Conversely, abnormal scans are seldom found in patients classified as T1-T2 or N0 and chances of "false positives" are high. 相似文献
35.
Gerardo Zanetta Consultant Stefania Chiari Consultant Sonia Rota Registrar Giorgio Bratina Professor rea Maneo Registrar Valter Torri Medical Statistician Costantino Mangioni Professor 《BJOG : an international journal of obstetrics and gynaecology》1997,104(9):1030-1035
Objective To assess the results of a policy of tailored conservative surgical management for young women with stage I ovarian carcinomas.
Design Retrospective study.
Participants Ninety-nine women aged 40 years or younger who underwent either primary surgery in our department or were referred after primary surgery performed elsewhere.
Methods Of the 99 women in our study, 56 underwent fertility-sparing surgery and 43 more radical surgery. Minimal requirements for conservative management were adequate staging and complete information about the therapeutic options. Factors important in the choice of the treatment were, age, wish to preserve fertility, histologic type and grade, and the stage of the tumour.
Results Conservative treatment was conducted in 84% of nulliparous and in 33% of parous women; 62% of grade 1 tumours, 48% of grade 2, and 50% of grade 3 were treated conservatively. With a median follow up of seven years, we observed five recurrences (9%) of carcinoma in women treated conservatively and five (12%) in those treated more radically. Two women (one in each treatment arm) were saved after recurrence. Two recurrences after conservative surgery involved the residual ovary (3.6%). Two women developed borderline tumour in the contralateral ovary and both were treated by surgery.
Conclusion After adequate staging and accurate information is given to the patient, conservative treatment may be safe in some women with early ovarian cancer. The risk of recurrence in the contralateral ovary is low. Conservative surgery may be also considered in some Stage I grade 3 tumours and in some women with stage IC tumours. 相似文献
Design Retrospective study.
Participants Ninety-nine women aged 40 years or younger who underwent either primary surgery in our department or were referred after primary surgery performed elsewhere.
Methods Of the 99 women in our study, 56 underwent fertility-sparing surgery and 43 more radical surgery. Minimal requirements for conservative management were adequate staging and complete information about the therapeutic options. Factors important in the choice of the treatment were, age, wish to preserve fertility, histologic type and grade, and the stage of the tumour.
Results Conservative treatment was conducted in 84% of nulliparous and in 33% of parous women; 62% of grade 1 tumours, 48% of grade 2, and 50% of grade 3 were treated conservatively. With a median follow up of seven years, we observed five recurrences (9%) of carcinoma in women treated conservatively and five (12%) in those treated more radically. Two women (one in each treatment arm) were saved after recurrence. Two recurrences after conservative surgery involved the residual ovary (3.6%). Two women developed borderline tumour in the contralateral ovary and both were treated by surgery.
Conclusion After adequate staging and accurate information is given to the patient, conservative treatment may be safe in some women with early ovarian cancer. The risk of recurrence in the contralateral ovary is low. Conservative surgery may be also considered in some Stage I grade 3 tumours and in some women with stage IC tumours. 相似文献
36.
Marangoni F Agostoni C Lammardo AM Giovannini M Galli C Riva E 《The British journal of nutrition》2000,84(1):103-109
While a wealth of data on the fatty acid composition of mature human milk has been published, limited information is available on the quantities of individual fatty acids supplied to the suckling infant with maternal milk, through the whole first year of life. Our aim was to qualitatively and quantitatively evaluate the fatty acid composition of human milk from Italian mothers, throughout extended lactation with particular emphasis on the long-chain polyunsaturated fatty acids. We have thus measured the total fat content and the concentrations of major fatty acids by quantitative GLC in pooled breast hindmilk collected from all feedings over 24 h at colostrum, 1, 3, 6, 9 and 12 months in ten mothers recruited after delivery of full-term infants. Total saturated fatty acids progressively increase and total monounsaturated progressively decrease as percentage levels, while among long-chain polyunsaturated fatty acids, percentages of arachidonic acid and docosahexaenoic acid decrease from colostrum up to the third month. Hindmilk total lipids (mg/dl) rise more than twofold up to 3 months, and then remain stable. The amounts (mg/dl) of linoleic acid and alpha-linolenic acid progressively increase, following the trend of total fat, while arachidonic and docosahexaenoic concentrations (mg/dl) remain stable throughout the whole nursing period. Assessment of the intakes per kg body weight shows different trends for the individual major long-chain polyunsaturated fatty acids supplied to the infant from hindmilk during exclusive breast-feeding (3 months). This information may be useful for the evaluation of infant intakes during extended lactation. 相似文献
37.
CONTEXT: Since the introduction of combined antiretroviral therapy, mortality rates in adults with human immunodeficiency virus type 1 (HIV-1) infection have decreased. However, little information is available outside the setting of controlled trials on survival of perinatally HIV-infected children treated with antiretroviral therapy. OBJECTIVE: To assess effect of availability of antiretroviral therapy on decreasing mortality in perinatally HIV-infected children. DESIGN: Population-based, multicenter longitudinal study involving data collected by the Italian Register for HIV Infection in Children. SETTING: A network of 106 pediatric clinical centers. SUBJECTS: A total of 1142 children born between November 1980 and December 1997 with perinatally acquired HIV infection with a median follow-up of 5.9 years. MAIN OUTCOME MEASURE: Time to HIV-related death calculated for birth cohort and calendar period and grouped by distribution of predominant type of antiretroviral therapy administered over time. RESULTS: Survival was longer in the 1996-1997 birth cohort (crude relative hazard [RH] of death, 0.39; 95% confidence interval [CI], 0.15-0.96) and 1996-1998 calendar period (crude RH of death, 0.65; 95% CI, 0.45-0.95) than in birth cohort and calendar period 1980-1995, but not when adjusted for maternal antiretroviral treatment during pregnancy and clinical condition at time of delivery, gestational age, and birth weight (adjusted RH of death, 0.55; 95% CI, 0.20-1.50, for birth cohort; and adjusted RH of death, 0.71, 95% CI, 0.43-1.16, for calendar period). In a multivariate model with 1980-1995 as comparison, the 1996-1997 birth cohort had an RH of 0.57 (95% CI, 0.22-1.47; P=.27) but RH for calendar period 1996-1998 was 0.63 (95% CI, 0.47-0.85; P<. 01). When the effects of birth cohort, calendar period, and type of antiretroviral therapy were evaluated simultaneously in the same model, the RH of death was not significantly different from 1.0 for the 1996-1997 birth cohort (P=.19) and calendar period 1996-1998 (P=. 83) suggesting a causal relationship between decreased risk of death and use of combination therapy. The RH of death in children receiving monotherapy or double or triple combination therapy was 0. 77 (95% CI, 0.55-1.08), 0.70 (95% CI, 0.42-1.17), and 0.29 (95% CI, 0.13-0.67), respectively, vs no antiretroviral therapy. CONCLUSION: Survival of perinatally HIV-infected children improved in 1996-1998 as a result of the introduction of combined antiretroviral therapies. JAMA. 2000;284:190-197 相似文献
38.
Videothoracoscopic approach in the treatment of intralobar pulmonary sequestration. Report of a case
The Authors report on the use of a videothorascopic approach in the treatment of a patient with intralobar bronchopulmonary sequestration. The latter is a rare malformation which more often than not manifests itself in young patients with hemophthisis, recurrent infection and cough. The condition is difficult to diagnose and is often diagnosed intraoperatively. The treatment is surgical resection. The videothorascopic approach was used in a young patient presenting a lesion of the left inferior lobe with polycyclic contours suspected of being an intralobar bronchopulmonary sequestration, along with medical history findings of cough and hyperpyrexia. The approach permitted identification of the lesion in the context of the left inferior lobe, safe identification and section of the abnormal systemic vessel supplying the lesion and subsequent inferior lobectomy. The postoperative course was uneventful and the patient was discharged on postoperative day 5 with an excellent esthetic and functional outcome. The videothorascopic approach should be taken into consideration for the diagnosis and treatment of intralobar bronchopulmonary sequestrations. 相似文献
39.
Exposure to mercury during the first six months via human milk and vaccines: modifying risk factors 总被引:3,自引:0,他引:3
Dórea JG 《American journal of perinatology》2007,24(7):387-400
Breastfeeding is the best natural protection infants have against morbidity and mortality, and the development of safe and effective vaccines has made it possible to immunize children against infectious disease. Both of these mechanisms for ensuring good health in children may be compromised by contact with mercury (Hg). Maternal exposure to environmental Hg during pregnancy can predispose nursing children to neurodevelopmental disorders. Despite the World Health Organization assurance that thimerosal-preserved vaccines are safe to use in infants, the United States, the European Union, and dozens of other countries have eliminated thimerosal as a vaccine preservative and stopped the immunization of children with such vaccines. Because of the increase in environmental pollution and the need to produce cheap and safe vaccines, there is a need to address the uncertainty of vaccine-ethylmercury risk of toxicity and Hg exposure during breastfeeding. 相似文献