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971.
972.
Sebire NJ; Sherod C; Abbas A; Snijders RJ; Nicolaides KH 《Human reproduction (Oxford, England)》1997,12(1):173-175
Gestation at delivery, birthweight and pregnancy outcome of surviving
fetuses from 127 multifetal pregnancies undergoing embryo reduction to
twins were compared to 354 chromosomally normal non-reduced dichorionic
twin pregnancies. First-trimester embryo reduction was carried out by
intracardiac injection of KCl. In 16 (12.6%) of the 127 multifetal
pregnancies reduced to twins, there was miscarriage of both fetuses before
24 weeks of gestation. The median interval between reduction and fetal loss
was 5 weeks (range 1-12). In livebirths, the median gestation at delivery
was 36 weeks (range 24-41) and the median difference in birthweight from
the appropriate mean was -0.94 SD (range -3.89-1.73 SD). Both fetal loss
before 24 weeks and the interval between embryo reduction and delivery were
significantly associated with the gestation at reduction (r = 0.40, P <
0.001 and r = -0.57, P < 0.001 respectively). In the pregnancies reduced
to twins compared to the non-reduced twins, the percentage of miscarriages
was higher (12.6 compared to 2.5%; chi 2 = 19.2, P < 0.001), the median
gestation at delivery was lower (36 compared to 37 weeks; t = -1.74, P <
0.05), and the median birthweight deficit was greater (-0.94 compared to
-0.65 SD: t = -4.1, P < 0.001).
相似文献
973.
Mesothelioma is a rare tumor that is considered an asbestos marker disease. It occurs in individuals following a longer latency period from first exposure than other asbestos-related diseases. The tumor also occurs in individuals with a wide range of exposures, including individuals with lower level or secondary exposures. In the present study lung tissue from 54 individuals with a pathological diagnosis of mesothelioma was evaluated for ferruginous body and uncoated asbestos fiber content. The data were compared with an earlier study of mesothelioma cases from the northwestern United States. Tissue was prepared via a digestion procedure, with the collected digestate reviewed by light microscopy for quantification of asbestos bodies and analytical transmission electron microscopy for determination of uncoated fiber burden. Twenty-seven cases in the present study had over 1000 ferruginous bodies per gram of dry tissue. The data suggest that amosite provides a more likely stimulus for ferruginous coating than the other forms of asbestos. All individuals were found to have asbestos fibers in their lung tissue. Amosite was the most commonly found fiber, with anthophyllite being the second most commonly found type of asbestos. The finding of tremolite in the tissue most often was associated with the finding of anthophyllite. A limited number of asbestos fibers of each type would have been seen in the light microscope, with the least detected being chrysotile. The majority of all fiber types were found as short fibers (< 8 mum), although some longer fibers were represented in each type of asbestos. The majority of the individuals were found to have mixed types of asbestos in their lungs. 相似文献
974.
Testicular neoplasms: 29 tumors studied by high-resolution US 总被引:2,自引:0,他引:2
Grantham JG; Charboneau JW; James EM; Kirschling RJ; Kvols LK; Segura JW; Wold LE 《Radiology》1985,157(3):775-780
High-resolution (10-MHz) ultrasonography produces extremely detailed anatomic images of the testis. The sonographic features most helpful in detecting tumors are mass, bright echogenic foci, and diffuse parenchymal texture change. Of 29 patients with testicular neoplasms, 21 (72%) had one or more masses, 19 (66%) had one or more echogenic foci, and nine (31%) had a diffuse parenchymal texture change. Bright echogenic foci were present in six (86%) of seven testes that had a regressed germ-cell tumor. In an attempt to define the histologic features of bright echogenic foci, we performed needle localization under real-time guidance on four operative specimens. We observed immature bone and cartilage, calcification, tubular atrophy and fibrosis, and focal noncalcific scarring. Discovery of occult testicular neoplasms was common (9/29); four patients were thought to have had "extragonadal" germ-cell tumors before abnormalities were found on the sonograms. 相似文献
975.
Hepatitis B in Wisconsin male prisoners: considerations for serologic screening and vaccination. 总被引:3,自引:0,他引:3 下载免费PDF全文
R F Anda S B Perlman D J D''Alessio J P Davis V N Dodson 《American journal of public health》1985,75(10):1182-1185
To develop a protocol for prevention of hepatitis B virus (HBV) transmission in Wisconsin prisons, we interviewed 619 male prisoners at incarceration to obtain information on hepatitis B risk factors. We defined previous infections by the presence of hepatitis B surface antigen (HBsAg), antibody to hepatitis B surface antigen (anti-HBs), or antibody to hepatitis B core antigen (anti-HBc). Logistic regression was used to develop a model of relative risk (RR) of HBV infection. Use of illicit intravenous (IV) drugs was the most important risk factor because of a high prevalence of IV drug use and an RR which ranged from 2.93-7.47. Other important risk factors were: prior hepatitis or jaundice (RR = 6.28), race (RR = 2.54 for Blacks, RR = 3.28 for Latinos), transfusion (RR = 3.00), and age. Previous imprisonment was not an independent risk factor for HBV, hence selective serologic screening and vaccination of prisoners are justified rather than mass screening and vaccination. Based upon prevalence of hepatitis B markers in subgroups, it is necessary to screen prisoners with prior hepatitis or jaundice, prior transfusion, and users of IV drugs. The identification of HBsAg carriers by such screening could prevent infection of "household" contacts. Users of IV drugs who are susceptible to HBV infection should be vaccinated. The remaining prisoners constitute a low-risk group for HBV infection and do not require serologic screening or vaccination. 相似文献
976.
Early response of the visceral pleura following asbestos exposure: an ultrastructural study 总被引:1,自引:0,他引:1
The acute in vivo response of the visceral pleura following intracheal instillation of amosite asbestos was examined by light microscopy and by transmission and scanning electron microscopy in the guinea pig model. Asbestos fibers were observed close to the pleura in all time periods but were never found within the pleura or subpleural regions proper. Thus, pleural changes occurred in the absence of direct fiber contact. Morphological changes in the pleural and subpleural areas were seen as early as 2 h after exposure and were associated with pathological alterations of the underlying parenchyma. The normally squamous mesothelial cells became pleomorphic in experimental animals, ranging from slightly cuboidal, to protruding "columnar-like" cells, to more bizarre forms. While many organelles remained unaltered, an increase in vacuolization in portions of the pleura indicated localized and advanced intracellular responses. Beginning at 4 h postexposure, varied numbers of particulate-free macrophages were seen on the pleural surface, and were considered an extension of the inflammatory response occurring in the underlying parenchyma. Early proliferation of the mesothelial cells, in limited areas of the pleura, and cytoplasmic extensions into the pleural space were also observed. Distortions of the basal lamina and smooth-muscle bundles accompanied the morphological changes in the pleural cells. A trend toward normality was observed in the longer time frames, but some areas of pleural change persisted through 3 mo postexposure. 相似文献
977.
Vierck Janet L. Byrne Katherine Mir Priya S. Dodson Michael V. 《Methods in Cell Science》2000,22(1):33-41
Procedures for preventing contamination in primary cell cultures must be carefully defined and strictly followed in order to obtain healthy cells. Protocols have been developed and refined in our laboratory for establishing primary cultures of muscle and fat stem cells without contamination from a variety of animals. Contamination of cell cultures is not only frustrating, but is also very expensive both in time and loss of materials. Through the consistent use of proper aseptic techniques, most instances of contamination may be avoided. We suggest that the basic principles detailed here will find wide applicability in the culturing of primary cells without contamination from many different types of animals and tissues. 相似文献
978.
Stewart Nathanial T. Byrne Katherine M. Hosick Howard L. Vierck Janet L. Dodson Michael V. 《Methods in Cell Science》2000,22(1):67-78
The selection of appropriate techniques to assay for markers of cell activity is important for obtaining optimal results in cell culture-based research. This paper is intended as a guide to many of the assays currently available and new techniques that have been recently introduced in the literature. This paper addresses both manual assay techniques, including the use of hemocytometers, phase contrast microscopy, cell staining, and the immunofluorescent antibody assay (IFA), and automated assays for cell activity, including stained optical density, proliferating cell nuclear antigen, creatine kinase assay, DNA quantification, electronic cell counting, flow cytometry, magnetic cell sorting, image analysis, chemiluminescence, radioisotope labeling, precursor incorporation, in-situ hybridization/ligand binding, and enzyme-linked immuno-culture assay (ELICA). Advantages/disadvantages and applicability of these assays to different areas of cell culture research are discussed, and guidelines for selecting an appropriate assay are suggested. 相似文献
979.
Generation of useful cell culture data 总被引:1,自引:0,他引:1
As the need for viable and interpretable cell culture systems increases, it is not sufficient to simply be successful at growing cells in vitro. Rather, vigilance is required to obtain repeatable data from these systems, especially if mechanistic or developmental experimental designs are attempted. We suggest that all aspects of basic cell culture are as important as growing cells. We offer the papers of this issue to help the cell scientist scrutinize and identify problems in many of these important areas, including obtaining tissue, eliminating microbial contamination, formulating a defined medium, isolating specific cell types from tissue and then using them for in vitro studies, cloning cells, selecting and developing methods for cell culture analyses, and recognizing abnormal cell culture activity. 相似文献
980.
Rob JM Strack van Schijndel Peter JM Weijs Rixt H Koopmans Hans P Sauerwein Albertus Beishuizen Armand RJ Girbes 《Critical care (London, England)》2009,13(4):1-11