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241.
Chronic granulomatous disease (CGD) is a rare inherited immunodeficiency disease that leads to severe recurrent infections. CGD is caused by defects in the phagocyte NADPH oxidase, a multiprotein enzyme that reduces oxygen to superoxide, a precursor of microbicidal oxidants. Less than 6% of CGD patients have an autosomal recessive form of the disease caused by mutations in NCF-2. This gene encodes p67-phox, a cytosolic oxidase subunit that associates with membrane-bound flavocytochrome b558 and regulates electron transfer. We studied six patients from five families with p67-phox deficiency and identified seven different mutant alleles. Patients from three of the kindreds were homozygous for their respective mutation, although the parents of only one family were known to be related. Five of the mutations have not previously been identified: (1) a missense mutation (383C-->T) in exon 5, (2) a nonsense mutation (196C-->T) in exon 3, (3) a missense mutation (230G-->A) in exon 3, (4) a nonsense mutation (298C-->T) in exon 4, and (5) a dinucleotide deletion (835-836 AC) from exon 9. Phagocytes from each of the patients analyzed failed to generate a measurable respiratory burst and had no detectable p67-phox protein. Our results further demonstrate that there is great heterogeneity among the mutations in p67-phox-deficient CGD patients, with no evidence for mutational hot-spots or a founder effect. Our data also support the hypothesis that the stability of p67-phox is particularly sensitive to missense mutations that cause amino acid substitutions within its N-terminal domain. In contrast, mutations predicting single amino acid changes elsewhere in the protein generally represent benign polymorphisms.  相似文献   
242.
The primate superfamily Cercopithecoidea (or Old World monkeys) is characterized by a widespread lack of the maxillary sinus, a paranasal pneumatic space found in most other eutherian mammals. Previous discussions of the distribution of pneumatization in the group, however, have been ambiguous and contradictory, and have been further complicated by discussion of a poorly defined structure named the "lateral recess," linked implicitly to the maxillary sinus. Computed tomography (CT) was applied to dry crania of all cercopithecoid genera to evaluate the morphological relevance of the term "lateral recess." Results suggest that the "lateral recess" is a structural consequence of changes in skull form unrelated to pneumatization. Thus, the term should be abandoned. All Old World monkeys (except the genus Macaca) are found to lack the maxillary sinus, but a previously undescribed bulla, only separated from the nasal cavity anteriorly, was discovered in the Chinese golden monkey Rhinopithecus. If this bulla is related to the paranasal sinuses, it suggests that the initial change in cercopithecoid cranial evolution was a suppression of pneumatic development, which may have been subsequently reversed twice in the history of the group, in Macaca and Rhinopithecus.  相似文献   
243.
The labelling of metabolites with the NMR active nucleus 13C allows not only metabolite enrichments to be monitored, but also the relative fluxes through competing pathways to be delineated. [2-13C, 15N]alanine was used as a metabolic probe to investigate compartmentation in superfused cerebral slices. Perchloric acid extracts of the tissue were investigated using 13C NMR spectroscopy. The spectra were obtained using a CryoProbe optimised for 13C detection (dual CryoProbe [13C, 1H]) in which the receiver and transmitter coils are cooled to approximately 20K to reduce contributions to noise in the signal obtained. Compared with conventional inverse geometry probe, the signal-to-noise ratio (S/N) was increased by approximately 17-fold using this device. A large proportion of alanine was initially metabolised over the first 20 min by glial cells, as indicated by the relative importance of the glial, only enzyme pyruvate carboxylase to the labelling pattern of glutamate, with the ratio of pyruvate carboxylase to pyruvate dehydrogenase derived glutamate being 0.25, and exported [2-13C, 15N]aspartate.Using the increased sensitivity of the CryoProbe, [2-13C, 15N]aspartate was also detected in the extracts of cerebral tissue. This metabolite could only have been derived via the pyruvate carboxylase pathway, and given the large export of the metabolite into the superfusion buffer suggests the occurrence of a "metabolon" arrangement of enzymes within glial cells.  相似文献   
244.
The effect of undernutrition in utero, during late gestation (from day 100), and early neonatal life on hypothalamic-pituitary function was investigated in female lambs born to ewes fed rations calculated to provide either 100% (high; H) or 70% (low; L) of the energy requirements to sustain a twin pregnancy. Following parturition in early spring, ewes and lambs were maintained on pasture with sward heights of 6 cm (H) or 4 cm (L) until week 8 of lactation and then sward heights of 5 cm (H) or 3 cm (L) until weaning at week 14. Mean lamb birth weights were 18% lower in L than H animals (P<0.05) and mean liveweights were 23% lower in the L animals (P<0.001) at weaning at 14 weeks of age. Liveweight differences were not significant at, or after, 26 weeks of age. There were no significant differences between pre-pubertal H and L animals, either before (26 weeks) or after ovariectomy (31 weeks), with respect to hypothalamic or pituitary activity, as measured by LH pulse frequency, pulse amplitude or mean plasma LH and FSH concentrations and the responses to GnRH injection as measured by LH peak amplitude, respectively. Similarly there were no differences in any of these variables in pubertal animals at 18 months of age. At 31 weeks of age, H animals had significantly lower pituitary GnRH receptor binding (P<0.01) and lower ERalpha mRNA content (P<0.05) than L lambs. There were no differences with treatment in the abundance of mRNA for LHbeta, FSHbeta or GnRH-receptor at 31 weeks of age or in pubertal animals aged 18 months, when there were no significant differences with treatment in GnRH receptor binding or ERalpha mRNA expression. It is concluded that effects on lifetime reproductive function of female sheep of undernutrition during late gestation and early neonatal life are unlikely to be expressed through permanent changes in hypothalamic-pituitary function and are therefore attributable to effects exerted directly on the ovary.  相似文献   
245.
246.
Kim NR  Han J 《Acta cytologica》2003,47(6):1103-1106
BACKGROUND: So-called primary giant cell tumor of soft tissue of low malignant potential is the rare soft tissue analogue of giant cell tumor of bone, occurring primarily in superficial soft tissue. To our knowledge, the cytologic findings in bulky giant cell tumor of deep soft tissue were described only once, and no further report on the subcutaneous giant cell tumor could be retrieved from the literature. CASE: A 58-year-old woman presented with a well-demarcated, 1.5-cm-diameter dermal tumor. Fine needle aspiration smears contained numerous osteoclastlike giant cells and mononuclear cells showing bland and vesicular nuclei. A small fragment of branching vasculature and 1 mitosis were found. Those cytologic findings were enough to suggest a diagnosis of giant cell tumor of soft tissue, confirmed as a deep dermal giant cell on surgical resection. CONCLUSION: Primary giant cell tumor of soft tissue of low malignant potential should be considered in the differential diagnosis of bland-looking giant cell-rich lesions. Awareness of its existence and knowledge of its cytologic features are important for a correct preoperative cytologic diagnosis.  相似文献   
247.
Three cDNAs encoding putative larval cuticle protein (LCP) were cloned from the mulberry longicorn beetle, Apriona germari. The three cDNA sequences were 309 bp, 396 bp and 408 bp in length, encoding 103, 132 and 136 amino acid residues, respectively. The predicted molecular masses for these LCPs were approximately 9.2 kDa (AgLCP9.2), 12.3 kDa (AgLCP12.3) and 12.6 kDa (AgLCP12.6). Pairwise identity among AgLCP9.2, AgLCP12.3 and AgLCP12.6 were relatively low. Each AgLCP contained a type-specific consensus sequence identifiable in other insect cuticle proteins. The deduced amino acid sequence of AgLCP9.2 is most similar to Bombyx mori LCP18 and those of AgLCP12.3 and AgLCP12.6 are both most similar to B. mori LCP17. Northern blot analysis revealed that the three AgLCPs showed epidermis-specific expression. The expression profile of AgLCPs after larval ecdysis revealed by Northern blot analysis that the high-level mRNA expression of AgLCPs was detected on the first day of larval ecdysis for AgLCP9.2, on the fifth day for AgLCP12.3 and from the first day of larval ecdysis to the fifth day after larval ecdysis for AgLCP12.6, demonstrating that AgLCP mRNAs are differentially expressed in epidermis after larval ecdysis.  相似文献   
248.
Surfactant protein-A (SP-A) plays multiple roles in pulmonary host defense, including stimulating bacterial phagocytosis by innate immune cells. Previously, SP-A was shown to interact with complement protein C1q. Our goal was to further characterize this interaction and elucidate its functional consequences. Radiolabeled SP-A bound solid-phase C1q but not other complement proteins tested. The lectin activity of SP-A was not required for binding to C1q. Because C1q is involved in bacterial clearance but alone does not efficiently enhance the phagocytosis of most bacteria, we hypothesize that SP-A enhances phagocytosis of C1q-coated antigens. SP-A enhanced by sixfold the percentage of rat alveolar macrophages in suspension that phagocytosed C1q-coated fluorescent beads. Furthermore, uptake of C1q-coated beads was enhanced when either beads or alveolar macrophages were preincubated with SP-A. In contrast, SP-A had no significant effect on the uptake of C1q-coated beads by alveolar macrophages adhered to plastic slides. We conclude that SP-A may serve a protective role in the lung by interacting with C1q to enhance the clearance of foreign particles.  相似文献   
249.
Pulmonary surfactant is a lipoprotein complex that lowers surface tension at the air-liquid interface of the lung and participates in pulmonary host defense. Surfactant proteins (SP), SP-A and SP-D, modulate a variety of immune cell functions, including the production of cytokines and free radicals. Previous studies showed that SP-A and SP-D inhibit lymphocyte proliferation in the presence of accessory cells. The goal of this study was to determine whether SP-A and SP-D directly suppress Th cell function. Both proteins inhibited CD3(+)/CD4(+) lymphocyte proliferation induced by PMA and ionomycin in an IL-2-independent manner. Both proteins decreased the number of cells entering the S and mitotic phases of the cell cycle. Neither SP-A nor SP-D altered cell viability, apoptosis, or secretion of IL-2, IL-4, or IFN-gamma when Th cells were treated with PMA and ionomycin. However, both proteins attenuated ionomycin-induced cytosolic free calcium ([Ca(2+) ](i)), but not thapsigargin-induced changes in [Ca(2+)](i). In summary, inhibition of T cell proliferation by SP-A and SP-D occurs via two mechanisms, an IL-2-dependent mechanism observed with accessory cell-dependent T cell mitogens and specific Ag, as well as an IL-2-independent mechanism of suppression that potentially involves attenuation of [Ca(2+)](i).  相似文献   
250.
Rae AL  Smith FW 《Planta》2002,215(4):565-568
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