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91.
92.
93.
Antiglomerular basement membrane (anti-GBM) disease is characteristically described with linear deposition of IgG along the GBM. We report two unusual cases of IgA and IgM anti-GBM disease associated with diffuse thinning of the GMB, and review the literature on atypical immunoglobulin species in this disorder. Both patients were male, aged 55 and 49 years, and presented with isolated microscopic haematuria, neither having shown evidence of impaired renal or pulmonary function on follow-up for 4 and 6 years respectively. Renal histology revealed minor focal mesangial changes only, but immunoperoxidase preparations demonstrated intense linear staining of the GBM with IgA in one case, and IgM with C3 in the other. On electron-microscopy there was diffuse thinning of the GBM in both cases, mean thickness 220 and 295 nm respectively (normal range 350-450 nm). Antinuclear antibodies were not detected and their glucose tolerance tests were normal. Assays for circulating IgG anti-GBM antibodies using indirect immunofluorescence (IF) and radioimmunoassay (RIA) were negative in both patients, although IgA anti-GBM antibodies with specificity confirmed by inhibition studies were identified in the first case. Thin GBMs in these patients may expose the Goodpasture antigen to toxic or infectious insults, thus altering its antigenic profile and promoting this unusual immune response. 相似文献
94.
E A Wanek J G Horgan F M Karrer R J Hall C M Rumack J R Lilly 《Journal of pediatric surgery》1990,25(1):146-148
From December 1986 to April 1989, 38 patients with biliary atresia (eight newly diagnosed) were evaluated with doppler ultrasound of the portal venous system. Peak and mean velocities were computer derived from the spectral waveform. Good velocity was greater than 15 cm/s, intermediate velocity was 8 to 14 cm/s, abnormal velocity was less than 7 cm/s or hepatofugal. Patients were grouped according to clinical status: group 1 (n = 14), normal liver function; group 2 (n = 15), recurrent cholangitis; group 3 (n = 2), established bile drainage but complicated cirrhosis; group 4 (n = 7), failed portoenterostomy. All patients with normal liver function (group 1) had good or intermediate velocities. Thirteen of 15 patients with recurrent cholangitis (group 2) had good or intermediate velocities. Both patients in this group with abnormal velocities required transplantation. In group 3 the patient with abnormal velocity is on the transplant waiting list. In group 4, abnormal velocities preceded or coincided with deterioration of liver function in five of seven patients. Doppler ultrasound provides useful anatomic information, determines direction of flow, quantitates velocity of flow, and, when performed serially, provides adjunctive information on liver status in children with biliary atresia. These preliminary results suggest that patients with abnormal or significantly decreasing velocity are destined for transplantation. Patients with good portal venous velocity warrant ongoing, aggressive surgical management. 相似文献
95.
电针改善硬膜外吗啡用于术后镇痛所引起的免疫抑制 总被引:1,自引:1,他引:0
为观察硬膜外吗啡和电针对术后患者免疫功能的影响,检测自然杀伤细胞(NKcell)活性和PHA诱导白细胞介素2(IL-2)水平在单纯胆囊切除术患者术前和术后第1、3、7天的动态变化情况。结果吗啡组NK活性在术后第1、3、7天抑制,手术组仅在术后第1、3天出现抑制,而抑制率低于同天的吗啡组,电针可拮抗吗啡引起的NK活性抑制加深状况。在术后第1天,手术组和吗啡组IL-2水平均下降,吗啡+电针组无明显变化,术后第7天吗啡+电针组IL-2升高接近正常人水平。表明电针能改善硬膜外吗啡引起的免疫抑制,促进术后机体的恢复。硬膜外吗啡结合电针是值得推荐的术后镇痛方法。 相似文献
96.
A lethal skeletal dysplasia with features of chondrodysplasia punctata and osteogenesis imperfecta: an example of Astley-Kendall dysplasia. Further delineation of a rare genetic disorder. 下载免费PDF全文
An unusual osteochondrodysplasia presenting with lethal neonatal short limbed dwarfism, defective ossification, and punctate calcification within cartilage is presented. The features resemble four cases previously described with Astley-Kendall dysplasia. 相似文献
97.
A H Hall S C Smolinske B Stover F L Conrad B H Rumack 《Journal of toxicology. Clinical toxicology》1992,30(1):23-37
A prospective study of 63 ibuprofen overdose cases in adults (14 years or older) reported to the Rocky Mountain Poison and Drug Center between March 1987 and February 1988 was done to determine the incidence of renal injury and utility of timed plasma levels. No serious toxicity was noted. No CNS or other significant toxicity was seen with ingestion of less than 3 g. Two patients with normal serum creatinines had minor elevations of the blood urea nitrogen after ingesting 4 and 4.8 g. Timed plasma levels (125 total) from patients without coingestants from this study (48) and previously published reports (77) were compared with a previously described nomogram. The resulting nomogram revision may be useful in determining which initially asymptomatic patients are likely to remain so. Renal function tests are not routinely required for patients ingesting less than 6 g. Four h of observation is sufficient for asymptomatic patients not requiring psychiatric admission. Plasma ibuprofen levels are not required for proper patient management. 相似文献
98.
J Hall 《The International journal of health planning and management》1989,4(3):235-246
Breast cancer, screening and mammography have caused considerable debate in several countries. This article explores the concept of best medical practice in the context of mammographic screening for breast cancer. Maximizing the use of technology, ignores the risks intrinsic to technological intervention. To do no harm in modern medical practice means largely doing nothing. Best medical practice, therefore, requires a balancing of benefits and risks so that best practice is that which does more good than harm. At the same time, not all interventions that do more good than harm can be funded out of the current health care budget. Thus, best medical practice is economically efficient practice. From the conceptual notion of what is best medical practice, this article turns to the problem of what that means in practical terms. Can we recognize best medical practice when it occurs? The identification, measurement and valuation of costs and benefits are discussed as a specific case study, in the context of breast cancer screening. Many of the difficulties involved here, particularly on the benefit side, are highlighted, especially in the context of QALYs. Yet, whatever the difficulties involved they have to be seen in the context of otherwise settling for something less i.e. inefficient medical practice. 相似文献
99.
100.
Stimulation of in vivo antibody production and concanavalin-A-induced mouse spleen cell mitogenesis by prolactin 总被引:3,自引:0,他引:3
Regulation of the immune system by neuroendocrine hormones is receiving increased attention. Prolactin, a hormone normally associated with lactation, has been shown recently to reconstitute immunosuppressed hypophysectomized rats. The present studies demonstrate that prolactin administration to normal mice results in a biphasic stimulation of antibody production to sheep red blood cells. While 100 and 200 micrograms bovine prolactin/animal stimulated antibody production, 400 micrograms had no effect. Potentiation of lectin-induced T-cell mitogenesis by prolactin was also biphasic. As the concentration of prolactin increased the incorporation of [3H]thymidine into the cells first increased and then decreased. Decreasing serum prolactin levels with the dopaminergic agonist bromocriptine resulted in a reduction of antibody titers to sheep erythrocytes and a modulation of thymic weight. These data show that prolactin can stimulate the immune system in a biphasic manner and that a reduction in the basal levels of this hormone results in an attenuated immune response. 相似文献