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971.
Effects of gastric bypass procedures on bone mineral density,calcium, parathyroid hormone,and vitamin d 总被引:2,自引:0,他引:2
Jason M. Johnson James W. Maher Isaac Samuel Deborah Heitshusen Cornelius Doherty Robert W. Downs 《Journal of gastrointestinal surgery》2005,9(8):1106-1111
Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data
on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals
after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic
preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had
or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by
9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n =
14; P<.001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year,
by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the
operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS)
by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS)
and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively
(25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the
first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the
first year.
Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18,
2005 (oral presentation). 相似文献
972.
Treatment of congenital cystic adenomatoid malformation-does resection in the early postnatal period increase surgical risk? 总被引:1,自引:0,他引:1
Young Tae Kim Jun Sung Kim June Dong Park Chang Hyun Kang Sook Whan Sung Joo Hyun Kim 《European journal of cardio-thoracic surgery》2005,27(4):658-661
OBJECTIVE: The recent development of fetal ultrasonography has allowed for an increasing number of prenatal diagnoses for congenital cystic adenomatoid malformation (CCAM). However, the appropriate surgical timing of these patients has not been studied as of yet. The aim of this study is to suggest a safe strategy for the treatment of CCAM by identifying the relationship between the timing of surgery and postoperative outcome. METHODS: Between 1987 and 2003, 40 patients (28 males, 12 females) underwent surgical resection for CCAM. The mean age was 38.6+/-9.1 (2 days-13 years) months. CCAM was diagnosed by prenatal ultrasonography in eight patients. Early operations were performed in four out of the eight. Operation was deferred until 2-12 months of age for the remaining four patients. RESULTS: Type I CCAM was found in 20 patients, type II in 20 and no patient exhibited type III. Five patients had associated pectus excavatum anomaly. There were no cases of operative mortality. Seventeen minor postoperative complications developed in 16 patients (40.0%): prolonged chest tube drain in 10, wound infection in 4, and 1 case of pneumonia, empyema and pleural space, respectively. The average hospital stay was 11.8 (6-29) days. During the mean follow-up period of 67.5 months, one patient died of accidental aspiration 7 months after operation during the postoperative recovery course of Ravich operation for pectus excavatum. The remaining patients reported doing well with normal physical activity. All five patients who underwent surgery at the age of under 1 month did not exhibit increased postoperative morbidity. CONCLUSIONS: We concluded that surgery for CCAM could be safely performed in all age groups with satisfactory long-term outcomes. It is suggested that early elective surgical correction can be recommended for a patient whose diagnosis was made in utero. 相似文献
973.
新基因Tctex5在雄鼠生殖细胞中的表达 总被引:1,自引:0,他引:1
目的探讨雄鼠生殖细胞中是否有Tctex5基因的表达。方法从三株体外培养的雄鼠生殖细胞CRL-1715、CRL-2053和CRL-2196细胞株中提取总RNA和蛋白,采用RT-PCR和Western blot分别从mRNA和蛋白质水平分析基因产物的表达。结果Tctex5基因在CRL-1715、CRL-2053、CRL-2196三株细胞中都有高表达。结论Tctex5基因作为一个未知功能的基因,在雄鼠生殖细胞中有丰富的表达,可能参与了精子发生的功能调节,作为男性正常生育的。个新的标志物,它可能在精子发生中扮演了一个重要的角色,该基因在雄性生殖细胞中的发现可能会对男性不育的诊断与治疗提供新的途径。 相似文献
974.
Exogenous advanced glycosylation end products induce diabetes-like vascular dysfunction in normal rats: a factor in diabetic retinopathy 总被引:2,自引:0,他引:2
Xun Xu Zhiping Li Dawei Luo Yufeng Huang Jianfeng Zhu Xiaojue Wang Honghui Hu C. Patrick 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2003,241(1):56-62
BACKGROUND. Diabetic retinopathy has been shown to be directly associated with the degree and duration of hyperglycemia, and advanced glycosylation end products (AGEs) have been implicated in this pathological process. The purpose of the experiments reported here was to study the effect of AGE deposition on retinal vascular damage which leads to diabetic retinopathy. METHODS. Intravenous injection of exogenous AGEs was used to treat wild-type non-diabetic Sprague-Dawley rats. One of the two retinal slides from each animal was treated using immunohistochemical staining to label retinal vascular AGE deposition, the other H&E staining for counting of capillary pericytes. The results were compared with the findings in untreated wild-type and diabetic controls and in rats treated with unmodified rat serum albumin (RSA). RESULTS. After 2 weeks of continuous treatment, AGEs were identified in the retinal vascular tissue of the AGE-RSA-injected group. The average number of retinal capillary pericytes per 10x100 microscope power field was 4.313+/-0.34 (mean +/- SD) in the AGE-RSA-injected group, compared with 5.798+/-0.481 in the control group ( P<0.01). CONCLUSION. These experiments demonstrate that AGEs, independent of other metabolic factors, can induce vascular change resembling that of diabetic retinopathy. 相似文献
975.
Gardenia C. G. Militão Daniel P. Bezerra Claudia Pessoa Manoel Odorico de Moraes Flavio A. F. da Ponte Mary Anne S. Lima Edilberto R. Silveira Letícia V. Costa-Lotufo 《Journal of natural medicines》2007,61(2):196-199
The purpose of this study was to investigate the antiproliferative activity of 2,3,9-trimethoxypterocarpan, a known pterocarpan
with cytotoxic activity against many tumor cell lines, in a panel of four leukemia cell lines (HL-60, Molt-4, Jurkat, and
K562) and on human peripheral blood mononuclear cells (PBMC). The pterocarpan showed IC50 ranging from 0.1 to 0.5 μg/ml at leukemic cells after 72 h of incubation, with K562 being the most resistant cell line. This
compound seemed to be selective to tumor cell lines, since at a concentration of 10 μg/ml after 72 h, it only reduced 19%
of viable peripheral mononuclear cells. 相似文献
976.
A high molecular weight arabinogalactan protein (AGP) from the pressed juice of Echinacea purpurea, known to exhibit immunomodulatory properties in vitro, was characterized. Alkaline hydrolysis was carried out, leading to
degradation of the protein core and to carbohydrate moieties linked to the amino acid responsible for binding. Gel permeation
chromatography of these AG subunits gave one peak with a molecular weight of 30 × 103 Da. Hydroxyproline (42.9% w/w) was detected as the dominant amino acid after alkaline hydrolysis and was thus identified as
the major amino acid responsible for the binding between the protein and the AG subunits via an O-glycosidic linkage. Large
amounts of glutamine/glutamic acid (24.5% w/w) and asparagine/aspartic acid (17.3% w/w) were also found. Polyclonal antibodies
raised against the intact AGP were shown to bind to the AG subunits too, indicating that the epitopes responsible for such
interactions are localized in the polysaccharide moiety of the AGP. 相似文献
977.
978.
Marco Frattini Enrico Vaienti Giovanni Soncini Francesco Pogliacomi 《Musculoskeletal surgery》2009,93(3):109-114
Tibial plateau fractures are complex injuries which, if not adequately treated, can lead to invalidating sequelae. They constitute
on average about 1% of all fractures, and up to 8% in patients over 65 years, and can be caused by both high- and low-energy
trauma. Unlike in younger subjects, treatment of tibial plateau fractures in the elderly is not univocal and depends on the
patient’s functional needs, bone quality and systemic comorbidities. In this retrospective study, 49 patients with a mean
age of 72 years, who underwent surgical treatment of a tibial plateau fracture, were assessed by the Rasmussen’s clinical
and radiological grading systems. Clinical and radiographic outcomes were satisfactory in 75.5 and 59.1% of cases, respectively.
Data were also analyzed, in terms of fracture type, age and gender, to detect any statistically significant correlation between
these parameters and clinical and radiographic outcomes. 相似文献
979.
Eung Y. Kim Dong-Hyun Kim Eunhye Yoo Hae-Jeong Park Xavier Golay Seung-Koo Lee Dong J. Kim Jinna Kim Dong I. Kim 《International journal of developmental neuroscience》2007,25(6):409-414
Previous studies have shown that maturation of the white matter in terms of its relative signal intensity changes on MRI is almost complete at 2-3 years of age. We hypothesized that quantitative analysis may show maturation of the white matter during childhood and adolescence. In the present study we performed multi-echo T2 relaxometry in 33 healthy subjects (girls, 15; boys, 18) aged 3-15 years. T2 relaxation times of the genu and splenium were measured. In healthy subjects, the T2 relaxation times were significantly correlated with age in both girls (r=0.611, p=.016) and boys (r=0.721, p=.001) in the splenium, but not in the genu (p>.05). To further confirm genu-to-splenium signal intensity ratio changes, a total of 389 brain MRIs were retrospectively selected from the patients who had normal results (189 girls/women, 200 boys/men; age range, 3-20 years). The genu-to-splenium signal intensity ratio was obtained from the T2-weighted images. In patients with normal MRI, the genu-to-splenium signal intensity ratio was significantly decreased with age (p<.001) by 16 years. The T2 relaxation times gradually increase in the splenium during childhood and adolescence, suggestive of maturation. 相似文献
980.
Sayime Aydin Bulent Ertugrul Berna Gultekin Guliz Uyar Erkin Kir 《BMC infectious diseases》2007,7(1):87