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61.
The well-known and extremely well-documented chimpanzees from Gombe National Park were analyzed for presence of skeletal pathologies. Of the 15 animals available for study, 11 were old and complete enough to permit systematic analysis. Of these, 10 showed some evidence of skeletal pathological involvement. The most common type of lesion seen resulted from trauma. Those chimps with the most fractures (Old Female, 3; Flo, 4; Hugo, 8) are consistently the oldest individuals in the sample. In addition to accidental falls, the most common cause of trauma was from interpersonal violence, resulting in bite wounds (see in two individuals) and fractures (see in three individuals). Conversely to trauma, degenerative disease was exceedingly rare in this population, found in no large intervertebral joints (N = 344) and only two major synovial joints (N = 186). In fact, the complete lack of osteophytosis, even in older individuals, stands in stark contrast to the situation seen in modern humans, perhaps in our species reflecting a biomechanical cost of bipedality.  相似文献   
62.
The response of Potamogeton crispus L. breakdown to controlled doses of different levels of chlorine and chlorine + ammonia was investigated over two years in outdoor experimental streams. In 1985, downstream riffles of 2 streams were dosed (observed in-stream concentrations) at ca. 10 μg/L Total Residual Chlorine (TRC), one stream at 64 μg/L TRC and one stream at 230 μg/L TRC. Two control streams were not dosed and the upstream riffles of each stream served as within stream controls. In 1986, the downstream riffle of one stream was dosed at 70 μg/L TRC and a second stream was dosed at 200 μg/L TRC. Four streams were also dosed with 2.5 mg/L NH3-N: one stream with no chlorine, one stream with ca. 10 μg/L TRC, one with 56 μg/L TRC, and one with 150 μg/L TRC. A seventh stream was dosed for 2 h at 2000 μg/L TRC and 2.5 mg/L ammonia and then allowed to recover (recovery stream). Each year, litter decomposition (degree day k values) was measured during two 35 day trials (Jun–Jul and Aug–Sep). In 1985, when streams were dosed with chlorine alone, decomposition was significantly reduced with the high (230 μg/L TRC) chlorine dose. Downstream decomposition was 27% (Jun–Jul) and 59% (Aug–Sep) of the upstream (control) rate. No other chlorine effects were found during this period. In Jun–Jul 1986, there was significantly lower decomposition in the downstream dosed sites of the 200 μg/L TRC alone stream, the 146 μg/L TRC + ammonia stream and the recovery stream; downstream decay rates were (respectively) 56%, 42% and 64% of the upstream control sites. No other up-down pairs were different in July 1986. In Aug–Sep, all three streams with chlorine + ammonia (6, 56 and 146 μg/L TRC + 2,5 mg/L ammonia) and the 70 μg/L TRC alone stream had significantly lower decomposition rates in the downstream dosed sites. For these streams, downstream decay rates ranged from 46% (high chlorine + ammonia) to 73% (low chlorine + ammonia) of the upstream control rates. No other up-down pairs were different during this trial. Up and downstream sites of the stream dosed with 2.5 mg/L ammonia alone were nearly identical for both trials (< 3% difference). These results indicate that TRC at less than 250 μg/L can significantly reduce litter decomposition and strongly suggest that addition of ammonia to chlorinated water can increase the toxic effect of chlorine. currently at the Department of Fisheries and Wildlife currently at the Department of Fisheries and Wildlife  相似文献   
63.
In order to determine whether the small-scale distribution of immature Ixodes dammini Spielman et al. corresponds closely to the activity patterns of white-tailed deer, Odocoileus virginianus (Zimmerman), these relationships were examined in a site on Long Island, New York, U.S.A. We first determined the extent and temporal pattern of adult ticks feeding on deer by examining twenty-three resident deer tranquilized during September-December 1985. I. dammini adults infested deer throughout this fall period, most abundantly during October and November. With radio-telemetry collars attached to deer we determined the relative frequency that they occupied 0.25 ha quadrats of the study site. During the following summer, we examined white-footed mice, Peromyscus leucopus (Rafinesque), that inhabited these quadrats and removed immature ticks from each. 8975 larval and 163 nymphal I. dammini were removed from 208 mice trapped in forty-three such quadrats. The frequency of deer using these quadrats was positively correlated with both the number of larval and of nymphal ticks per mouse. These results suggest that risk of I. damminiborne zoonotic disease may be decreased by locally reducing deer density in sites that experience intense human activity.  相似文献   
64.
Summary Deficient arylsulfatase-A activity is diagnostic of a neurodegenerative human lysosomal storage disease, metachromatic leukodystrophy. Paradoxically, similar enzyme deficiency also occurs in normal individuals, who are known as being pseudo arylsulfatase-A deficient. We showed previously that this phenotype is associated with a structural gene mutation that produces an exceptionally labile enzyme. We now report on the nature and consequence of this mutation. When the mutant arylsulfatase-A is deglycosylated by endoglycosidase H, only one smaller molecular species was generated, instead of the two from the normal enzyme. This is consistent with the loss of one of the two N-linked oligosaccharide side chains known to be present on the wild-type enzyme. Quantitative analysis of mannose and leucine incorporation showed that the mutant enzyme incorporated two- to tenfold less mannose than the normal enzyme on a molar basis. This deficient glycosylation was specific to arylsulfatase-A. Another lysosomal enzyme not affected in this mutation, beta-hexosaminidase, was glycosylated normally in the mutant cells. The remaining single oligosaccharide side chain released from the mutant arylsulfatase-A by pronase digestion was normally processed to complex and high-mannose forms. However, the high-mannose side chains contained 30% fewer phosphorylated residues than those of the normal enzyme. Nevertheless, this reduced level of phosphorylation did not prevent targeting of the mutant enzyme to the lysosomes, a process normally mediated through phosphorylated mannose residues. In conclusion, pseudo arylsulfatase-A deficiency is a unique human mutation associated with reduced glycosylation and phosphorylation of a lysosomal enzyme with the loss of one of the two carbohydrate side chains. The mutation results in greatly reduced enzyme stability, thus indicating a role for oligosaccharides in maintaining enzyme stability within the degradative environment of the lysosomes. However, the residual catalytic activity or subcellular targeting of the mutant enzyme was not affected. These properties probably account for the benign clinical presentation of pseudo arylsulfatase-A deficiency.Abbreviations PD Pseudo arylsulfatase-A Deficiency - ARA Arylsulfatase-A  相似文献   
65.
Knowledge of the diseases of great apes in captivity is essential for captive management of self-sustaining populations. This survey of medical and pathology records of orangutans, gorillas, and one chimpanzee at the National Zoological Park was conducted to provide a data base for improving health care of captive apes. Strongyloidiasis, balantidiasis, and entamoebiasis were recurrent problems in adult and juvenile apes of all species. Cardiac fibrosis also was prevalent in middle-aged apes and was a major cause of mortality. Bacterial infections were prevalent in perinatal orangutans and resulted in the death of two. For gorillas, rheumatoid arthritis associated with mycoplasma infections, and infertility were major problems. Because the pathogenesis of many of these lesions is unknown, survival of great ape populations in captivity may depend on future research on these problems.  相似文献   
66.
Summary The accumulation of mansonones E and F was investigated in Ulmus americana L. seedlings 5 weeks after inoculation with three aggressive and three non-aggressive isolates of Ophiostoma ulmi (Buism.) Nannf. The three non-aggressive isolates stimulated significantly more mansonone E and F accumulation than the three aggressive isolates of O. ulmi. Mansonone induction also varied within both the aggressive and the non-aggressive groups. Aggressive and non-aggressive isolates were recovered in equal frequencies from the inoculation wounds, whereas the aggressive isolates were recovered more frequently than the non-aggressive isolates 15 cm and 25 cm up the seedlings' stem. Vascular browning in the outer xylem of the seedlings correlated with mansonone E and F accumulation. Mansonone accumulation in U. americana seedlings is therefore associated with vascular browning and a reduction in fungal spread.  相似文献   
67.
The young sporocysts had a wrinkled sporocyst wall, numerous papillae on the wall surface and the wall was granular and porous. In the itraconazole-treated culture, the walls of the young sporocysts were also wrinkled, but the characteristic papillae were replaced by larger lumps which were densely packed and coated the entire surface of the sporocyst wall. The mature sporocysts walls were smooth and possessed numerous papillae. In the itraconazole-treated culture, the walls of mature sporocysts walls were also smooth but possessed densely packed larger lumps instead of papillae. At higher magnification, each of the lumps were found to consist of numerous globules. No pores were observed as they were in the normal sporocyst wall.  相似文献   
68.
Cryptococcus neoformans was instilled intranasally into mice which were periodically sacrificed to determine the course of infection. Cryptococci persisted within the nasal passages throughout the 90 day study. Extranasal dissemination began 14–28 days after instillation and was still demonstrable 90 days post-exposure. Ten percent mortality was observed in mice receiving 106 cryptococci, while no mortality was observed in mice exposed to 103 or 104 cryptococci. Our research suggests that nasal colonization with C. neoformans can precede pulmonary and systemic cryptococcosis by weeks or months.  相似文献   
69.
The CSF and sera of 7 patients with Parkinson's disease were investigated immunocytochemically, in order to see if antibodies were present which recognized DA-ergic cell bodies in glutaraldehyde fixed rat brain. In 2 patients a marked labeling of DA-ergic neurons in the substantia nigra was observed, identified by anti-DA antiserum and by 6-OHDA induced degeneration, but also other neurons in the ventral mesencephalon were recognized. The other patients were weakly positive or negative. Sera gave unspecific labelling of all neurons. In one patient the sub-classes of IgG were investigated and found to be of IgG3 (labeling nerve terminals) and of IgG1–2, low affinity type (recognizing perikarya). The epitopes recognized have not been identified, but are unlikely to be DA-like, since blocking experiments and ELISA-tests gave negative results. The possible clinical importance of the results are discussed.Special Issue dedicated to Prof. Holger Hydén.  相似文献   
70.
Abstract The cell surface hydrophobicity of Renibacterium salmoninarum strains was examined using a salt aggregation method. Those strains which were virulent in the test animal were sticky, auto-agglutinating and possessed a hydrophobic cell surface. Those strains with a low virulence were non-sticky, non-agglutinating and failed to aggregate in a high molar salt. Strains could not be distinguished using biochemical tests. There was no change in hydrophobicity following re-isolation of the bacteria from experimentally infected rainbow trout, Salmo gairdneri .  相似文献   
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