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1.
Twenty-four patients treated with 150 mg amitriptyline per day for an episode of major depression underwent a standardized heart rate analysis (HRA) before therapy and after 14 days. The battery of cardiovascular reflex tests included the determination of the coefficient of variation (CV) while resting and during deep respiration, a spectral analysis of heart rate, the heart rate response to standing, and the Valsalva manoeuvre. The results of the initial HRA did not differ from a group of 24 normal control subjects matched for age and sex. On day 14 of treatment the patients showed significantly reduced values of heart rate variability in all tests (P<0.0001), probably due to the anticholinergic side effects of amitriptyline. Heart rate increased form 78.1 to 93.6 bpm on average (P<0.0001). Abnormal CV at rest was registered in 96% of the patients; during deep respiration 29% showed abnormal CV results. An abnormal spectral analysis was found in 100% of the cases (low frequency peak: 42%, mid-frequency peak: 100%, high frequency peak: 79%). The heart rate response to standing was abnormal in 75% and the Valsalva test in 33% of the cases. Eighty-eight percent of the patients fulfilled the criteria of a cardiovascular autonomic neuropathy under the conditions of amitriptyline therapy. As yet, the consequences of these changes for the patients have not been sufficiently elucidated. 相似文献
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This article describes how genetic components of disease susceptibility can be evaluated in case-control studies, where cases and controls are sampled independently from the population at large. Subjects are assumed unrelated, in contrast to studies of familial aggregation and linkage. The logistic model can be used to test collapsibility over phenotypes or genotypes, and to estimate interactions between environmental and genetic factors. Such interactions provide an example of a context where non-hierarchical models make sense biologically. Also, if the exposure and genetic categories occur independently and the disease is rare, then analyses based only on cases are valid, and offer better precision for estimating gene-environment interactions than those based on the full data. 相似文献
4.
Plasma Concentrations of Mycophenolic Acid Acyl Glucuronide Are Not Associated with Diarrhea in Renal Transplant Recipients 总被引:2,自引:0,他引:2
T. Heller T. van Gelder K. Budde J. W. de Fijter D. Kuypers W. Arns J. Schmidt L. Rostaing S. H. Powis K. Claesson I. A. M. MacPhee E. Pohanka J. Engelmayer G. Brandhorst M. Oellerich V. W. Armstrong 《American journal of transplantation》2007,7(7):1822-1831
The aim of this study was to determine whether plasma concentrations of the acyl (AcMPAG) and phenolic (MPAG) glucuronide metabolites of mycophenolic acid (MPA) were related to diarrhoea in renal transplant patients on mycophenolate mofetil (MMF) with cyclosporine (CsA) or tacrolimus (TCL). Blood samples (0, 30, 120 min) were taken at days 3, 10, week 4, months 3, 6 and 12 for determination of MPA, MPAG and AcMPAG. MPA-AUC was estimated using validated algorithms. Two hour AUCs were calculated for MPAG and AcMPAG. Immunosuppressive therapy consisted of CsA/MMF (n= 110) and of TCL/MMF (n= 180). In 70/290 (24%) patients 86 episodes of diarrhoea were recorded during 12 months. Significantly more patients on TCL (31.1%) suffered from diarrhea compared to CsA (12.7%). MMF dose, MPA-AUC and the 2 h AUCs of MPAG and AcMPAG did not differ between patients with and without diarrhoea. Plasma AcMPAG and MPAG concentrations were substantially higher in patients on CsA compared with TCL, while MPA-AUC was lower in the former group. These data support the concept that CsA inhibits the biliary excretion of MPAG and AcMPAG, thereby potentially reducing the risk of intestinal injury through enterohepatic recycling of MPA and its metabolites. 相似文献
5.
Mark L. Kraus Judith S. Weis Peddrick Weis 《Archives of environmental contamination and toxicology》1988,17(3):355-363
Tolerance to mercury in two populations of the grass shrimpPalaemonetes pugio was examined at different stages of this animal's life cycle. One population came from a mercury-contaminated creek, Piles Creek (PC), near industrialized Linden, New Jersey. The other population came from a relatively clean area, Big Sheepshead Creek (BSC), near non-industrialized Tuckerton, New Jersey. Larval grass shrimp showed no significant difference between populations in terms of mortality in 0.01 mg/L HgCl2, although treated BSC larvae metamorphosed significantly (P < 0.05) more slowly than their respective control group. While no BSC larvae survived the 0.0125 mg/L methylmercuric chloride (meHg) treatment, PC larvae exposed to 0.0125 mg/L meHg survived as well as their controls, indicating enhanced tolerance to meHg in this population.Adult shrimp were exposed for 14 days to control, 0.025 mg/L meHg, 0.025 mg/L HgCl2, 0.05 mg/L meHg, or 0.05 mg/L HgCl2 PC shrimp were significantly (P < 0.05) more tolerant to both 0.025 mg/L meHg, and 0.025 mg/L HgCl2 than were the BSC adults.Polyacrylamide gel electrophoresis suggests that both populations of shrimp are capable of producing a metallothionein like protein (MT) in response to treatment with HgCl2; MT is found in higher levels in field-caught PC shrimp than in field-caught BSC shrimp. MT was not present in field-collected, viable eggs from either population. 相似文献
6.
Andreas Büttner Bilge Bavbek Peter A. Winkler Parviz Mehraein Serge Weis 《Neuropathology》1997,17(2):94-100
The clinical, radiological, and pathological features in 10 cases of ganglioglioma are described. The clinical data were derived from the patients' medical records, including a review of the age, sex, details of the presenting symptoms, radiological imagings, surgical intervention, and the clinical outcome. Age ranged from 1 to 66 years (mean 29); there were five males and five females. The tumors were located in the fronto-medial, bifrontal, temporal, temporo-basal, temporo-parieto-occipital, and parietal lobes; the 3rd ventricle; the cervicothoracic spinal cord; and the conus medullaris. The presenting symptoms were focal seizures, headaches, hemiparesis, paraparesis, and tetraparesis. In four patients, gross total resection was achieved and in the remaining six patients only subtotal resection was possible. Tumor recurrence occurred in three patients, 1 year, 14 months, and 2 years after the first operation. The histopathologic appearance of gangliogliomas showed a broad variation of the neuronal, glial, and stromal component. Studying proliferation characteristics, labeling for Ki-67 ranged from 0 to 13.7% (mean 4.1) and for PCNA from 0 to 32.1% (mean 20.4). Due to their favorable prognosis, early recognition and correct diagnosis are important in order to avoid progressive neurological deficits and unnecessary aggressive therapy. The application of immunohistochemistry for both neuronal (synaptophysin, NSE, NFP) and astrocytic (GFAP) cell markers, as well as proliferation markers, are recommended in the diagnostic setting for gangliogliomas. The treatment of choice is total surgical resection. The role of radio- and chemotherapy is still controversial. 相似文献
7.
W W Loney B J Kudchodkar S Weis M B Clearfield J Shores A G Lacko 《American journal of therapeutics》1997,4(9-10):301-309
Subjects with high-density lipoprotein cholesterol (HDL-C) values of less than 47 mg/dL (mean 35.6 +/- 5.5 mg/dL) were selected for this study to examine relationships between plasma lipids, lipoprotein components, and the outcome of gemfibrozil therapy. Changes in plasma lipoprotein subfractions were determined to better understand the previously observed variability of the responses in both HDL-C and triglycerides to gemfibrozil. Based on the data collected, an attempt was made to identify pretreatment lipid parameters that may be predictive regarding the efficacy of gemfibrozil therapy. Serum samples were analyzed at the outset and after the conclusion of 12 weeks of gemfibrozil therapy. Because the HDL-C response to therapy was highly variable, the data from patients were separated into two groups, responders (>20% increase in HDL-C) and nonresponders (<20% increase in HDL-C). The lipid components of lipoprotein subfractions were evaluated using multiple regression analysis yielding predictive models that show the relationship between specific lipoprotein subfractions and the percentage change in HDL-C and posttreatment triglyceride levels. Group classification was then predicted with 78% accuracy using specific lipoprotein subfractions to estimate an individual's percentage change in HDL-C. The major difference between the responder and nonresponder groups was their respective correlations between triglyceride-lowering and changes in HDL-C. In the responder group, there was a significant correlation between the changes in HDL-C and the lowering of triglycerides (r = 0.61, p = 0.03), whereas the nonresponder group showed no such correlation (r = 0.17, p = 0.52). The predictive model also proved to be highly accurate in forecasting the effectiveness of the triglyceride-lowering action of gemfibrozil in this group of patients. 相似文献
8.
Judith S. Weis Richard Cohen Jill K. Kwiatkowsi 《Aquatic toxicology (Amsterdam, Netherlands)》1987,10(5-6):279-290
Fiddler crabs, Uca pugilator, were exposed to the insect growth regulator diflubenzuron (Dimilin®) at 0.5, 5, and 50 μg/l after multiple autotomy of one chela and five walking legs. Regeneration of the first walking leg was monitored, and time to ecdysis, mortality, and morphology of the regenerated limbs observed. Continuous exposure to the chemical produced a dose-dependent retardation of regeneration. Animals molting in the higher concentrations exhibited significant mortality at ecdysis. Exposure to the pesticide for a single week produced similar but less severe effects. However, if crabs molted while in the pesticide, significant mortality was observed. The presence of sediment in the container with the crab moderated the effects of the pesticide, but did not eliminate them.
The regenerated limbs of the crabs that survived ecdysis were found to have lesions in the form of black areas in which the cuticle was improperly developed. These lesions were seen in crabs that had been in the pesticide for only one week (week 2 or week 3) as well as those that had had continuous exposure. They were also seen in crabs that regenerated in Dimilin with sediment. In addition, the number of setae on limbs was reduced compared to the number on limbs that had regenerated in clean sea water. 相似文献
9.
A 65-year-old female had polyglucosan body myopathy, usually called "polysaccharide storage myopathy" that presented with increasing distal paresis and only slight weakness of the proximal limb girdle musculature. Muscle biopsy revealed dystrophic changes that could have been mistaken for muscular dystrophy, and the characteristic light as well as electron microscopic features of polyglucosan bodies varying in number at the three sites of muscle biopsies studied (deltoid, quadriceps femoris, and anterior tibial muscle). In addition, there were occasional nonspecific paracristalline mitochondrial inclusions. No abnormal polyglucosan deposits were found in the sural nerve biopsy. Morphometric evaluation of nerve fiber cross sectional areas revealed some degree of demyelination and remyelination, and of nerve fiber degeneration and regeneration. Unlike a series of 10 unselected control sural nerves with Renaut bodies, hypomyelinated nerve fibers were more numerous adjacent to Renaut bodies. This is the first case of polyglucosan body myopathy in which the axon/myelin ratio and the axonal circularity factor in the sural nerve is evaluated and in which a definite lack of polyglucosan bodies or other abnormal glycogen storage products in a peripheral nerve is documented. 相似文献
10.
Cytogenetic effects of methylmercury in embryos of the killifish,Fundulus heteroclitus 总被引:1,自引:0,他引:1
Dean M. Perry Judith S. Weis Peddrick Weis 《Archives of environmental contamination and toxicology》1988,17(5):569-574
Fertilized eggs of the killifish,Fundulus heteroclitus, were exposed experimentally to methylmercury (MeHg) to evaluate whether this compound induced cytogenetic effects expressed in the embryos. An additional objective was to assess cytogenetically whetherFundulus embryos from groups that were determined to be more susceptible to the teratogenic effects of MeHg were also more susceptible to its mutagenic effects. Embryos exposed to 0.05 mg/L MeHg for 1 and 7 days post-fertilization were preserved in 10% formalin for cytological examination, while unfixed embryos from the same clutches were evaluated for teratogenic effects. Untreated embyros from each clutch served as controls. Cytogenetic-cytological analyses of fixed treated susceptible embryos that exhibited teratogenic effects revealed decreased mitotic counts (5.0-fold), and increased chromosomal aberrations (2.5-fold) when compared to their controls. There were also decreased mitotic counts (1.5-fold) and increased chromosomal aberrations (2-fold) in embryos from resistant groups when compared to their controls. Exposure to MeHg also retarded development. Forty to fifty percent of the susceptible and resistant control embryos reached the tail-bud stage, but only 28% of the treated resistant and none of the treated susceptible embryos reached this stage. There was also a significant correlation (P < 0.05) between teratogenic and mutagenic effects of MeHg in early stages ofFundulus. 相似文献