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11.
Dr. med. Dipl.-Soz. T. Krones E. Schlüter S. El Ansari T. Wissner R. Zoll G. Richter 《Gyn?kologische Endokrinologie》2004,2(4):245-250
Preimplantation genetic diagnosis (PGD) has been vigorously debated in Germany ever since the Bundesärztekammer (BÄK) published a draft of guidelines for PGD in March 2000. Many stakeholders such as churches, medical societies, and diverse associations have participated in the discussion. However, little is known about the attitudes of experts, directly affected patient groups, and the public in Germany. In several studies that are part of the German research program on ethical implications of the Human Genome Project, representative surveys were undertaken to assess the attitudes of the general population (n=1017), five relevant expert groups (n=879), and couples at high risk for genetic disorders(n=324) towards PGD and prenatal diagnosis (PD). All groups favor legislation for PGD. Differences exist in regard to the extent of their approval. For 17% of the high-risk couples with a persisting desire for a child, PGD performed in a neighboring country is the most probable reproductive option. These results should be carefully considered in the ongoing legislation process on human reproduction in our country. 相似文献
12.
D Loutradis K Stefanidis P Drakakis K Kallianidis A El Sheikh S Milingos K Siskos S Michalas 《Gynecological endocrinology》2003,17(2):101-106
The purpose of this study was to investigate the ovarian response and the receptivity of the endometrium in women pre-treated with micronized progesterone. Eighty-two normogonodotropic women undergoing in vitro fertilization were studied. Thirty received micronized progesterone 1500 mg/day from day 21 of the cycle for a minimum of 2 weeks, and 52 did not receive micronized progesterone (control group). A gonadotropin releasing hormone agonist (GnRH-a) was administered to all the patients in the follicular phase (flare-up). Twenty-five cycles were cancelled for fertilization failure due to male factor, 12 (40%) in the progesterone group and 13 (25%) in the control group (p = 0.271). There was no difference in the number of oocytes retrieved (7.3 +/- 5 vs. 8.2 +/- 4), fertilization rate (50.8% vs. 65%), clinical pregnancy rate (16.6% vs. 25%) or implantation rate (8% vs. 14%). In the progesterone group cases without fertilization, we performed two biopsies to evaluate the receptivity of the endometrium. Pinopode expression was noted 7 days after oocyte retrieval. It seems that the administration of micronized progesterone in the previous cycle does not affect the ovarian response to the combination of follicular phase GnRH-a and gonadotropins, nor the receptivity of the endometrium. 相似文献
13.
R. El Galta C. M. Van Duijn J. C. Van Houwelingen J. J. Houwing-Duistermaat 《Annals of human genetics》2005,69(4):373-381
In genetic epidemiological studies informative families are often oversampled to increase the power of a study. For a proband‐family design, where relatives of probands are sampled, we derive the score statistic to test for clustering of binary and quantitative traits within families due to genetic factors. The derived score statistic is robust to ascertainment scheme. We considered correlation due to unspecified genetic effects and/or due to sharing alleles identical by descent (IBD) at observed marker locations in a candidate region. A simulation study was carried out to study the distribution of the statistic under the null hypothesis in small data‐sets. To illustrate the score statistic, data from 33 families with type 2 diabetes mellitus (DM2) were analyzed. In addition to the binary outcome DM2 we also analyzed the quantitative outcome, body mass index (BMI). For both traits familial aggregation was highly significant. For DM2, also including IBD sharing at marker D3S3681 as a cause of correlation gave an even more significant result, which suggests the presence of a trait gene linked to this marker. We conclude that for the proband‐family design the score statistic is a powerful and robust tool for detecting clustering of outcomes. 相似文献
14.
Conference Reports: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de. 相似文献
15.
16.
J. M. Porcher C. Lafuma R. El Nabout M. P. Jacob P. Sébastien P. A. Borm S. Honnons G. Auburtin 《International archives of occupational and environmental health》1993,65(Z1):S209-S213
This research is designed to evaluate a number of biological markers to estimate harmful exposure on coal miners from different mining regions in France and to relate the outcome to differences in prevalence of coal worker pneumoconiosis (CWP) between these regions. Eight epidemiological groups of active and ex-miners (smokers and non-smokers) have been selected in the French collieries (North, Lorraine and Provence) according to their occupational and pneumoconiotic status. The following biomarkers have been evaluated: cellularity of sputum, elementary analysis of particles in TEM/EDAX, plasma neutral metalloendo peptidase elastase type (NMEP), leucocyte elastase (HLE), fibronectin (FN) and elastin peptides. Pulmonary alveolitis, expressed by sputum cellularity, is different between active workers groups but not related to the general background of pneumoconiosis prevalence in the French collieries. In the plasma parameters, fibronectin, HLE and NMEP significantly increased in all groups of coal mine workers as compared to the control group, except for fibronectin parameter in Lorraine collierie. The degree of increase of these parameters allow us to discriminate the different groups and suggest that plasma FN, HLE and NMEP may be considered as biological markers of chronic inhalation of coal mine dust particles. The decrease of elastin peptides level in the Lorraine group alone suggests a specific alteration of elastin metabolism. These parameters were not related to the development of pneumoconiosis and its degree of severity. 相似文献
17.
Myofibroblasts and the progression of diabetic nephropathy 总被引:23,自引:3,他引:20
Essawy M; Soylemezoglu O; Muchaneta-Kubara E; Shortland J; Brown C; El Nahas A 《Nephrology, dialysis, transplantation》1997,12(1):43-50
Background. The cellular mediators of progressive
renal fibrosis in diabetic nephropathy remain unknown. Myofibroblasts have
been implicated in the pathogenesis of experimental and clinical renal
fibrosis. Their role in the progression of diabetic nephropathy is the
subject of this study.Subjects and methods. We have
studied by immunohistochemistry the expression of cytoskeletal proteins
associated with the activation of myofibroblasts; &agr;-smooth-muscle
actin (&agr;-SMA), vimentin (Vi) and desmin (D), in the kidneys of 25
patients with diabetic nephropathy (5 patients with diabetic nephropathy (5
patients had a superimposed glomerulonephritis). Comparisons were made with
normal tissue for three kidneys removed for renal-cell carcinoma.
Correlations were studied between clinical and biochemical parameters with
the expression renal cytoskeletal proteins. Results.
In normal kidneys, cells expressing &agr;-SMA were confined to the
vascular media and adventia while immunoreactive Vi was detected in
glomerular epithelial cells. In diabetic kidneys, cells expressing
&agr;-SMA were detected primarily in the renal interstitium and to a
lesser extent in some glomeruli in association with mesangial
proliferation. Vimentin immunostain decreased in glomeruli displaying
diabetic hyalinosis and sclerosis. By contrast, strong Vi immunoreactivity
was noted in atrophic diabetic tubules and to a lesser extent in the
interstitium. Desmin was not detected in either normal or diabetic kidneys.
Close correlations were observed between the expression of renal
cytoskeletal proteins and the progression of renal insufficiency.
Interstitial &agr;-SMA proved to be a predictor of progressive diabetic
nephropathy (R2 for 1/serum Cr slope=0.608,
P=0.00001). This predictive parameters; tubular atrophy
(R2=0.477, P=0.00004) and interstitial fibrosis
(R2=0.28, P=0.001). Conclusion.
We have demonstrated in this study the neoexpression of cytoskeletal
proteins within diabetic kidneys. This has allowed the identification of
new predicting histological markers for the progression of diabetic
nephropathy. 相似文献
18.
19.
The purpose of this study was to determine the nature and amounts of prostaglandins (PGs) produced by squamous carcinoma cells (SCC) and the sensitivity of these cells to non-steroidal anti-inflammatory drugs. SCC of four lines of the tongue and one line of facial epidermis of humans were incubated in phosphate buffer solution with 14 C-arachidonic acid (AA). Radioactive metabolites in aqueous methanol were chromatographed on Sep-Pack CIS cartridges, separated and quantitated by means of TLC, autoradiography, and liquid scintillation counting. The results showed that cyclooxygenase products, PGs, were the major products formed by all cell lines, and PGE2 was predominant among the PGs detected. Two radioactive bands corresponding to PGF2α and three unseparated standards of PGA2 , 15-keto-PGE2 , and 13,14-dihydro-15-keto-PGE2 were detected in lesser amounts. Very small amounts of the lipoxygenase products 12-and 15-HETE were found. The concentrations of indomethacin, ibuprofen and aspirin required to inhibit 50% of PGE2 synthesis (IC50 ) by SCC lines were .008- .080, .080–6.4 and 32–88 μM, respectively. 相似文献
20.