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101.
102.
Higashikawa K Furuki K Takada S Okamoto S Ukai H Yuasa T Ikeda M 《Industrial health》2000,38(2):181-188
The present study was initiated to examine the quantitative relationship between blood lead (Pb-B) and urinary delta-aminolevulinic acid (ALA-U) among Pb-exposed workers, and to find a threshold Pb-B level to induce an increase in ALA-U. For this purpose, pairs of venous blood and spot urine samples were collected from 8,274 men and 5,856 women (14,130 workers in total) who were occupationally exposed to inorganic lead. The blood and urine samples were analyzed for Pb-B and ALA-U by atomic absorption spectrometry and colorimetry, respectively, and the correlation between pairs of measures were subjected to statistical analysis. The assumption of the 3rd degree regression for correlation gave a substantially greater correlation coefficient (0.645 for men and 0.619 for women) than 1st or 2nd degree regression, whereas only very small improvement in the coefficient was achieved with 4th to 6th degree ones. Logarithmic conversion of the parameters was not effective in improving the correlation. The assumption of the 3rd degree regression followed by calculation of the local minimum gave 22, 29 and 23 micrograms/100 ml Pb-B for men, women, and men + women, respectively, as the threshold Pb-B to induce ALA-U increase. Pb-B to elevate ALA-U to the 95% upper normal limit (8 mg/l, common to men and women) was 62, 50 and 58 micrograms/100 ml for men, women and men + women, respectively. The validity of the 3rd degree regression assumption as a tool to calculate a threshold from experimental or epidemiological data is discussed. 相似文献
103.
Antisense RNA-mediated reduction of p53 induces malignant phenotype in nontumorigenic rat urothelial cells 总被引:2,自引:1,他引:2
p53 mutation is commonly associated with high-grade, high-stage human
urothelial carcinomas. Recent studies suggest that p53 mutation in low-
grade, low-stage bladder carcinomas may be correlated with the progression
of the disease. In the present study, we used antisense RNA methodology in
vitro to evaluate the significance of the loss of p53 function at an early
stage of urinary bladder carcinogenesis. An immortalized nontumorigenic rat
urothelial cell line (MYP3) that strongly expresses wild-type (WT) p53 was
transfected with a plasmid (pcDL-SR alpha-296) containing a rat WT p53 cDNA
in antisense orientation. The transfection resulted in a significant
reduction in p53 mRNA expression and protein synthesis, in stimulation of
anchorage- dependent growth, and in acquisition of anchorage-independent
growth potential. Three such clones, when tested in athymic nude mice, all
formed muscle-invasive, high-grade transitional cell carcinomas at s.c.
injection sites. When cells were inoculated into an orthotopic site
(urinary bladder), one of two antisense transfectants tested formed bulky
tumors in the bladder in all seven nude mice and metastases to lungs in
three of the seven mice. Analysis of these cells revealed a decrease in the
expression of p21 (WAF1, sdi1, or CIP1) and retinoblastoma (Rb) gene
product. Phosphorylation of Rb protein was not inhibited when the cells
were starved. No significant difference was observed in the expression of
p16 protein. In cell cycle analysis, all antisense transfectants tested
escaped from G1 arrest by starvation. Furthermore, secretion of interleukin
(IL)-6 into culture medium was increased significantly. Treatment with
anti-IL-6 antibody suppressed anchorage-dependent growth. This study
directly demonstrates that the loss of p53 function at an early stage of
urothelial carcinogenesis may result in acquisition of a malignant
phenotype by regulating IL-6 production as well as cell cycle related
genes.
相似文献
104.
Hiroaki Okamoto Akira Nagatomo Hideo Kunitoh Hiroshi Kunikane Koshiro Watanabe 《Cancer chemotherapy and pharmacology》1998,42(4):307-312
Purpose: Carboplatin doses can be individualized using the formula of Calvert et al. (Calvert formula) dose (mg) = area under the
plasma concentration versus time curve (AUC) · [glomerular filtration rate (GFR) + 25]. Creatinine clearance (Ccr), either
measured by the 24-h method or calculated by the formula of Cockcroft and Gault [Cockcroft-Gault (CG) formula], is often substituted
for the GFR. The CG formula is based on patient weight, age and sex, and the serum creatinine (Cr) concentration. Another
method for predicting carboplatin clearance (CL) using patient characteristics has also been proposed by Chatelut et al. (Chatelut
formula). This study was undertaken to evaluate the performance of the three formulae in predicting standard- and low-dose
carboplatin pharmacokinetics. Methods: A total of 52 patients with advanced lung cancer were enrolled in this pharmacokinetic study; 37 received standard-dose
carboplatin and 25 received low-dose carboplatin. The Cr concentration was measured using an enzymatic assay. The three formulae
were used to predict carboplatin CL. The median absolute percent error (MAPE) for each formula was evaluated by comparing
the calculated and observed CL. For comparison of AUCs, free platinum plasma concentrations were measured at intervals up
to 24 h after carboplatin administration. AUCs were determined and compared with predicted values. Results: In the standard-dose carboplatin group, the MAPEs for the prediction of carboplatin CL from the 24-h Calvert, CG-Calvert
and Chatelut formulae were 13%, 12% and 23%, respectively. In the low-dose carboplatin group, the corresponding MAPEs were
27%, 18% and 44%, respectively. Observed standard-dose carboplatin AUCs after aiming for target AUCs of 5 and 6 mg · min/ml
using the Calvert formula based upon the 24-h Ccr were 5.3 ± 0.8 and 5.9 ± 0.8, respectively, indicating a small and acceptable
bias compared with that predicted from the dosing formula. Conclusions: The pharmacokinetics of standard-dose carboplatin were accurately predicted by the Calvert formula based upon either 24-h
or CG-calculated Ccr, but not by the Chatelut formula. Either CG-calculated or 24-h Ccr can be substituted for the GFR in
the Calvert formula for the determination of individual doses. The poor predictability of the Chatelut formula found in this
study might be the result of a differences in either the Cr assay or the patient population. Therefore, formulae which attempt
to estimate GFR are not necessarily valid if either the Cr assay or the patient population is changed.
Received: 23 July 1997 / Accepted: 16 December 1997 相似文献
105.
106.
Kase M Sakamoto K Yamagata T Watanabe K Kunikane H Okamoto H Nagatomo A 《Kyobu geka. The Japanese journal of thoracic surgery》2000,53(12):1055-1057
A 29-year-old woman was referred to our hospital for an abnormal shadow on chest roentgenogram. She had no symptom but its shadow was pointed out about 20 years ago. Chest CT scan showed a sharply demarcated homogenous mass measured 10 x 10 mm in the S4 segment. The tumor was resected with video-assisted thoracoscopic surgery under CT-guided marking wire inserted. Microscopic examination suspected cavernous hemangioma. Immunohistological staining demonstrated most lining cells of the cavernous structure stained positively for von Willebrand factor antibody, which suggests that this tumor was associated with endothelium. Then we decided that this tumor was pulmonary cavernous hemangioma. 相似文献
107.
Hand-assisted laparoscopic surgery for a large gastrointestinal stromal tumor of the stomach 总被引:6,自引:1,他引:6
Hiroshi Yano Yutaka Kimura Takashi Iwazawa Hirotoshi Takemoto Mitsunobu Imasato Takushi Monden Shigeru Okamoto 《Gastric cancer》2005,8(3):186-192
We report two cases of large gastrointestinal stromal tumor (GIST) of the stomach that were successfully treated by hand-assisted laparoscopic surgery (HALS). Two patients, a 56-year-old woman and a 60-year-old man, were admitted to our department for the treatment of a large submucosal tumor of the stomach. After gastrointestinal endoscopy, ultrasonography, computed tomography, and magnetic resonance imaging, we suspected that the masses, measuring 7.0 cm and 8.0 cm in diameter, respectively, were GISTs in the stomach. However, preoperatively, we could not rule out the possibility of malignant neoplasms, because they had been bleeding or gradually growing. Hand-assisted laparoscopic wedge resection was safely performed for the diagnosis and treatment of the submucosal tumor of the stomach. The immunohistochemical diagnosis in both patients was GIST of the stomach with intermediate-grade malignancy. HALS may be a good indication for large GISTs of the stomach that are difficult to diagnose preoperatively, whether they are malignant or benign, because it is safe and minimally invasive, promoting rapid recovery. 相似文献
108.
Intraosseous microcystic meningioma 总被引:2,自引:0,他引:2
Extradural ectopic meningioma is a rare tumor. We report on an example of microcystic meningioma arising in the skull of an
elderly woman. Radiological examination revealed a localized osteolytic lesion in the left parietal bone. At surgery, it was
discovered that the tumor was located within the skull without any evidence of extraosseous extension. The light microscopic,
immunohistochemical and ultrastructural features were consistent with a microcystic variant of meningioma. To our knowledge,
this is the first case of an intraosseous microcystic meningioma, and we believe that this type of meningioma should be considered
in the differential diagnoses of myxoid bone tumors of the calvarium.
Received: 10 January 2000 Revision requested: 21 February 2000 Revision received: 8 March 2000 Accepted: 13 March 2000 相似文献
109.
110.
Maruichi M Takai S Sugiyama T Ueki M Oku H Sakaguchi M Okamoto Y Muramatsu M Ikeda T Miyazaki M 《Experimental eye research》2004,79(1):111-118
Chymase is a chymotrypsin-like serine protease contained in the secretory granules of mast cells. Recently, we reported that chymase activity and the number of chymase-positive mast cells in conjunctival tissues were significantly increased during the wound healing process in a hamster model of glaucoma surgery. However, it has been unclear the role of chymase on conjunctival scarring. In the present study, we evaluated the effect of dog chymase on cell proliferation of fibroblasts established from canine Tenon's capsule and the effect of a chymase inhibitor on scarring in a canine conjunctival flap model. After a fibroblast cell culture was established from canine Tenon's capsules, the fibroblasts were incubated in the presence of dog chymase (5-20 ng ml(-1)). Cell proliferation was evaluated by bromodeoxyuridine incorporation. In a canine conjunctival flap model, a sponge treated with a chymase inhibitor, Suc-Val-Pro-Phe(P)(OPh)(2), or placebo was placed in between the conjunctiva and sclera and the conjunctival incision was closed. One week after the surgery, adhesion degree was assessed, and chymase activities in the conjunctival lesion and in the areas of the conjunctiva and sclera were measured. In cultured canine Tenon's capsule fibroblasts, dog chymase significantly increased cell proliferation, and this chymase-dependent proliferation was completely suppressed by the chymase inhibitor. In the canine surgical model, chymase activity in placebo-treated eyes was significantly increased compared to control eyes, while it was significantly decreased by treatment with the chymase inhibitor. Scores for adhesion degree in the chymase inhibitor-treated eyes were significantly decreased in comparison with those in placebo-treated eyes. The conjunctival area in the chymase inhibitor-treated eyes was also suppressed to 52.6% compared with that in placebo-treated treated eyes. In conclusion, chymase stimulates proliferation of fibroblasts derived from canine Tenon's capsule and chymase may play an important role in scarring after glaucoma surgery. 相似文献