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51.
E. Casari M. Alfano M. Valente G. D. Clarke G. Ferni V. Grazioli 《Osteoporosis international》1997,7(6):539-543
The ovariectomized rat is the most commonly used animal model of human postmenopausal osteoporosis, exhibiting a high rate
of bone turnover with resorption exceeding formation. At present, bone turnover is quantified directly by dynamic histomorphometry.
The aim of the present study was to determine whether the measurement of the urinary output of some specific bone collagen
catabolites — pyridinolines and hydroxylysine glycosides — could be used to indirectly monitor the initial phase of bone turnover
increase in ovariectomized 90-day-old rats. Ninety-day-old female rats were randomly divided into three groups (n=6): ovariectomized, sham-operated and non-treated controls. Urine samples (24 h) were collected 6 days before surgery and
twice weekly for the 4 weeks following ovariectomy. Urinary excretion of pyridinoline (PYD), deoxypyridinoline (DPD), glucosyl-galactosyl-hydroxylysine
(GGHYL) and galactosyl-hydroxylysine (GHYL) were measured. As expected, ovariectomy was associated with a significant decrease
in bone mineral density in both the proximal tibial and distal femoral metaphysis. Compared with both sham-operated and control
animals, ovariectomized rats showed significant increases in PYD, GGHYL and GHYL urinary output 8 days after surgery and in
DPD output after 15 days. These changes were maintained throughout the study. The results confirm that measurement of the
urinary excretion of pyridinolines and hydroxylysine glycosides represents a powerful tool for detecting the onset of bone
turnover in ovariectomized 90-day-old rats. 相似文献
52.
目的 研究联合补充大豆异黄酮和钙对去卵巢大鼠骨质疏松的预防作用。方法 将50只3月龄SD雌性大鼠摘除卵巢后按体重随机分成5组:假手术对照组、手术对照组、大豆异黄酮组(40mg/kgBW)、钙组(100mg/kgBW)、钙+大豆异黄酮组(Ca100mg/kgBW+SI40mg/kgBW)。连续灌胃饲养3个月后测定大鼠血清骨钙素,左侧股骨测定骨密度和骨钙含量、右侧股骨进行骨组织形态学计量分析。结果 Ca+SI组血清BGP水平和股骨骨密度均高于其他去卵巢各组(P〈0.05),但低于Sham组(P〈0.05);Ca+SI组大鼠股骨的骨钙含量与Ca组、Sham组差异均无统计学意义;在去卵巢各组大鼠中手术对照组、大豆异黄酮组和钙组大鼠的骨小梁数目和骨小梁厚度显著减少,骨小梁间距明显增宽,与钙+大豆异黄酮组相比有显著差异(P〈0.05)。结论 与单独补充大豆异黄酮或钙相比,大豆异黄酮与钙的联合应用能够更有效地预防去卵巢大鼠骨质疏松的发生。 相似文献
53.
54.
Bone remodeling during the development of osteoporosis in paraplegia 总被引:11,自引:0,他引:11
Professeur A. Chantraine B. Nusgens Ch. M. Lapiere 《Calcified tissue international》1986,38(6):323-327
Summary Osteoporosis developing during the first weeks after the onset of traumatic paraplegia was studied with cortical and cancellous
samples of iliac crest and tibia of 14 patients, and compared to normals. We used a procedure of bone particle fractionation
(according to degree of mineralization) that allowed us to establish a profile reflecting the metabolic remodeling of bone
and to analyze the organic matrix of the newly synthesized tissue. In paraplegics, we observed a large increase in the proportion
of little calcified bone in the cortical as well as in the cancellous bone. Based on amino acid analyses, we found a decreased
number of hydroxyproline residues in the newly synthesized organic matrix from paraplegia bone resulting either from an alteration
of the prolyl hydroxylation or from the presence of an excess of noncollagen polypeptides. These results, together with previously
published data reporting increased urinary hydroxylproline and calcium kinetic parameters, suggest an enhanced rate of skeletal
remodeling in acute paraplegia. When investigated 2 years after injury, the patterns of distribution approach that of normal
subjects. 相似文献
55.
M. Ito T. F. Lang M. Jergas M. Ohki M. Takada T. Nakamura K. Hayashi H. K. Genant 《Calcified tissue international》1997,61(2):123-128
This study examined trabecular bone mineral density (BMD) in Japanese women with and without spinal fracture, and compared
the results to American women with and without fracture. The quantitative computed tomography (QCT) systems used at the University
of California, San Francisco (UCSF) and at Nagasaki University were cross-calibrated. Normative BMD was assessed with the
K2HPO4 liquid phantom in 538 Americans aged 20–85 years, and with the B-MAS200 phantom in 577 Japanese aged 20–83 years. These BMD
were adjusted for use with the Image Analysis solid phantom using the result of cross-calibration. The trabecular BMD in 111
postmenopausal American women (55 with fracture), and in 185 postmenopausal Japanese women (67 with fracture) were compared
for investigation of the difference in BMD values relative to fracture status. The absolute BMD values in Japanese were lower
than those in Americans, and the differences were greater with advancing age. The magnitude of the BMD difference was 8.6,
20.5, 38.1 mg/cm3 in women aged 20–24 years, 40–44 years, 60–64 years, respectively. In premenopausal women, BMD began to decrease at the age
of 20 in Japanese, whereas the peak bone mass was maintained until the age of 35 in the American women. In immediate postmenopausal
women, BMD significantly decreased in both populations. In later postmenopausal women, BMD significantly decreased with age
in the Japanese women but decreased less rapidly in the American women. The aging decrease of BMD was 1.4% and 2.2% per year
in the later postmenopausal American and Japanese women, respectively. The fracture threshold is considered to be lower in
Japanese women. However, the BMD difference between American and Japanese women with fracture was similar to that without
fracture. The Z-scores of fracture subjects versus controls were 2.9 in American and 1.8 in Japanese women. In conclusion,
Japanese women were found to have a lower BMD and lower fracture threshold than American women. The significant decrease of
spinal trabecular BMD in late postmenopause is potentially responsible for the higher prevalence of spinal fracture in Japanese
women.
Received: 18 December 1995 / Accepted: 23 September 1996 相似文献
56.
Vitamin D metabolites can prevent estrogen depletion-induced bone loss in ovariectomized (OVX) rats. Our aim was to compare
the bone-protective effects of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3), 1α,25-dihydroxyvitamin D2 (1,25(OH)2D2), 1α-hydroxyvitamin D3 (1α(OH)D3), and 1α-hydroxyvitamin D2 (1α(OH)D2) in OVX rats. 1α(OH)D3 and 1α(OH)D2 are thought to be activated in the liver to form 1,25(OH)2D3 and 1,25(OH)2D2, respectively. Forty-four 12-week-old female Fischer-344 rats were either OVX or sham-operated (SHAM). Groups of OVX rats
(n = 7 each) received vehicle alone, 1,25(OH)2D3, 1,25(OH)2D2, 1α(OH)D3, or 1α(OH)D2, starting 2 weeks after surgery. All vitamin D metabolites were administered orally at a dose of 15 ng/day/rat. Urine and
blood samples were collected 6, 9, 12, and 16 weeks after surgery. Serum samples were analyzed for total calcium and phosphate.
Calcium, phosphate, creatinine, and free collagen cross-links (ELISA) were determined in urine. After tetracycline double
labeling, the rats were sacrificed 16 weeks postsurgery, and the proximal tibiae and the first lumbar vertebrae were processed
undecalcified for static and dynamic bone histomorphometry. 1,25(OH)2D3 and, to a slightly lesser extent, 1,25(OH)2D2 elevated vertebral cancellous bone mass in OVX rats to a level beyond that observed in SHAM animals, and both compounds increased
serum calcium and urinary calcium excretion to similar extents. 1α(OH)D3 and 1α(OH)D2 resulted in a 64% and 84%, respectively, inhibition of ovariectomy-induced vertebral cancellous bone loss. In the proximal
tibial metaphysis, all vitamin D metabolites tested could only partially prevent post-OVX trabecular bone loss, with a tendency
for 1α(OH)D3 to be the least active compound. The effects of 1α(OH)D3 and 1α(OH)D2 on calcium homeostasis differed markedly, however. The mean increase in urinary calcium excretion over the whole experiment
was fivefold for 1α(OH)D3, whereas the corresponding increase for 1α(OH)D2 was only twofold. We conclude that, compared with 1α(OH)D3, 1α(OH)D2 combined at least equal or higher bone-protective activity in OVX rats with distinctly less pronounced effects on calcium
homeostasis. This effect was not due to a differential action of the corresponding main activation products, 1,25(OH)2D3 and 1,25(OH)2D2.
Received: 2 May 1996 / Accepted: 18 October 1996 相似文献
57.
Effect of Psoas Training on Postmenopausal Lumbar Bone Loss: A 3-Year Follow-Up Study 总被引:4,自引:0,他引:4
M. A. Mayoux-Benhamou F. Bagheri C. Roux G. R. Auleley J. P. Rabourdin M. Revel 《Calcified tissue international》1997,60(4):348-353
The present study completed a previous randomized trial that demonstrated the protective effect of 1-year psoas training
on lumbar bone loss in postmenopausal women. Computerized tomography had been carried out at the beginning (CT1) and at the
end (CT2) of this trial. In the present study, 67 women having completed the first trial were asked to practice psoas exercises
(60 hip flexions in sitting position with a 5 kg weight on the knee) for 2 additional years with a third CT control at the
end of this period (CT3). The aim of this complementary study was to assess the compliance rate and long-term effect on bone
of daily psoas muscle training over a longer period. Twenty-one women performed this daily psoas training for 3 years from
CT1 to CT3, and 14 acted as controls during the same period. Fourteen women were controls during the first year (from CT1
to CT2) but practiced psoas training during the following 2 years (from CT2 to CT3). Four women were psoas trained during
the first year (from CT1 to CT2) and subsequently crossed over to the control group for the last 2 years. The compliance rate
was 42%, with an attendance rate of 88%. The lumbar bone loss was lower in the 21 women trained over the 3 years (−3.26 ±
28.45 mg/cm3) than in the 14 untrained women (−16.79 ± 8.51 mg/cm3) (P= 0.02). The bone loss was not significantly reduced between the two periods of the study in the 12 women having been controls
from CT1 to CT2 and having crossed over to the active training group from CT2 to CT3. Psoas training may be effective against
lumbar bone loss. We conclude that specific training may play a contributing role in the preventive strategy to avoid osteoporosis.
Received: 23 February 1996 / Accepted: 25 October 1996 相似文献
58.
K. S. Chon M.E. D. J. Sartoris M.D. S. A. Brown Ph.D. P. Clopton M.S. 《Skeletal radiology》1992,21(7):431-436
Although alcoholism is a known risk factor for osteoporosis, there are few published reports on alcoholism-associated bone loss. To study alcoholism-associated bone loss, this study used a dual X-ray absorptiometry (DXA) densitometer to measure lumbar and femoral bone mineral density (BMD) in a previously little-studied population: 32 relatively healthy, nonhospitalized, Caucasian, alcoholic men with a period of abstinence longer than that previously studied (median abstinence 4.0 months, range 3 days–36 months). DXA is a new, highly precise densitometric method with many advantages over the methods used in previous studies. The subjects had statistically significant bone loss at three sites: lumbar spine, femoral neck, and Ward's triangle (multiple correction adjusted two-tailed P < 0.008). Compared to the mean BMD of sex-, age-, and race-matched norms, the subjects' average femoral neck, Ward's triangle, and lumbar BMDs were, respectively, 0.56, 0.69, and 0.57 standard deviations (SDs) below the normative values.This study was partially funded by a National Institutes of Health Short Term Research Training Grant (PHSHL 07491) to K.C. 相似文献
59.
P. Lips MD C. Cooper D. Agnusdei F. Caulin P. Egger O. Johnell J. A. Kanis U. Liberman H. Minne J. Reeve J. Y. Reginster M. C. de Vernejoul I. Wiklund 《Osteoporosis international》1997,7(1):36-38
The morbidity of osteoporosis is caused by fractures. Vertebral fractures lead to pain and disability and a decrease in quality of life. A Working Party of the European Foundation for Osteoporosis has developed a specific questionnaire for patients with established vertebral osteoporosis. This questionnaire is intended for use in clinical trials. The questionnaire consists of questions and visual analogue scales in the following domains: pain, activities of daily living, jobs around the house, mobility, leisure and social activities, general health perception and mood. The questionnaire has been translated from English into French, German, Italian, Hebrew, Swedish and Dutch. The questionnaire is currently being validated in a multicentre study involving patients with stable osteoporosis and control subjects. Preliminary results indicate that the reproducibility is sufficient and that the questionnaire is able to discriminate between patients with vertebral osteoporosis and control subjects. 相似文献
60.
利塞膦酸钠在防治绝经后骨质疏松症中的作用 总被引:2,自引:0,他引:2
目的 观察利塞膦酸钠防治绝经后骨质疏松症的疗效。方法 绝经后骨质疏松症共4 8例 ,随机分为 2组 ,对照组 2 4例 ,服安慰剂 ;试验组 2 4例 ,服利塞膦酸钠 5mg/d。另外 ,两组患者每日均服钙维生素D3 合剂 (凯思立 ) 1片 ,两组共服药 12个月 ,试验后 0、1、3、6、9、12个月进行随访。结果 利塞膦酸钠组腰椎、股骨颈及大粗隆的骨密度均明显升高 (P <0 0 5 ) ,其中腰椎骨密度治疗前为 0 80± 0 0 9,治疗后 6个月及 12个月均达到 0 82± 0 0 9,增加率为 2 93%及 2 85 % ,均明显高于对照组 (P <0 0 5 )。 6个月及 12个月治疗总有效率试验组为 80 95 %及 71 4 3% ,显著高于对照组的4 5 4 5 %及 31 82 % (P <0 0 5 )。两组患者均无严重副作用。结论 利塞膦酸钠能明显提高绝经后骨质疏松症患者的骨密度 ,副作用轻。 相似文献