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Some syndromes that include gingival fibromatosis are associated with abnormalities of the hands and feet. The purpose of this work was to establish whether gingival fibromatosis, as an isolated disease, can be connected with disturbances in the development of the digitopalmar structures. In three families with 40 members, fibromatosis manifested in 16 (7 males and 9 females). The disease was transmitted as an autosomal dominant trait. Dermatoglyphics were analyzed in the proband in each family and in their fathers who had fibromatosis. The analysis showed the presence of patterns in IV interdigital areas in all patients. The fathers of 2 probands had double loops in the IV interdigital area, which is very rare in the general population (frequency, 0.6%). The position of the axial triradius was moderately distal (t') in 1, and markedly distal (t") in another, and in 4 it was borderline (tb). Total finger ridge count was increased, which indicated the increased size of the volar embryonal pads. Distorted dermatoglyphic findings may be considered microform abnormalities of the fingers and hands. Since dermatoglyphics are highly genetically controlled and reflect the status of the embryonal pads, the results suggest disharmony in the development of the mesodermal structures of the hands.  相似文献   
3.
A successful pregnancy is dependent on the development of adequate placental circulation. The abnormalities of placental vasculature may result in a number of gestational pathologies, including fetal loss. The aim of our study was to determine whether women with f V Leiden are at an increased risk of pregnancy loss. For this purpose we assessed three groups of women. In a prospective group we examined 30 females with spontaneous abortions for f V Leiden. In a retrospective group we assessed the frequency of abortions in 80 women (172 pregnancies) with f V Leiden (72 heterozygous, 8 homozygous) from 57 unrelated families. In a control group we evaluated the frequency of abortions in 45 women without f V Leiden. Factor V Leiden was found in 3% of women in the 1st group. Fetal loss occurred in 10% of women in the 2nd group and in 9% in the 3rd group. Factor V Leiden was not found to be a risk factor for fetal loss in our study group.  相似文献   
4.
Lymphatic abnormalities in fetuses with posterior cervical cystic hygroma   总被引:5,自引:0,他引:5  
We studied the structure and number of lymph vessels in 12 spontaneously aborted previable fetuses with posterior cervical cystic hygroma and generalized edema of variable origin (monosomy X, trisomy 21, trisomy 13, suspected Noonan syndrome, and lethal multiple pterygium syndrome) and compared them to 5 therapeutically aborted, apparently normal fetuses. We found that in the non-45,X fetuses with cystic hygroma and edema the lymphatic vessels at all studied sites were dilated and appeared increased in number. The 45,X fetuses had no recognizable lymphatic vessels in the edematous cutaneous tissue of the limbs, and only occasional dilated vessels in the wall of the nuchal cystic hygroma and in the lungs. These findings may be useful in differentiating between monosomy X and other conditions causing nuchal cystic hygroma in specimens in which the fetus was incomplete and/or cytogenetic study could not be done.  相似文献   
5.
Flow diverter devices have become a routine first-line option for treatment of an increasing population of intracranial aneurysms at many neurovascular centers. Despite the promising results of flow diverter stents on anterior circulation, incomplete occlusion on the presence of fetal posterior circulation has been described on several reports. Here we describe a novel technical alternative to conventional flow diversion approach for this specific subgroup of aneurysms using the low-profile flow diverter, Silk Vista Baby. The device was selectively placed into the fetal type posterior cerebral artery in half-T configuration for the treatment of a posterior communicating aneurysm using a transcirculation approach through the anterior communicating artery. This represents a useful and effective technique and should be considered when encountering the above-described situation.  相似文献   
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Most mitochondrial proteins are encoded in the nucleus and translated in the cytoplasm as larger precursors containing NH2-terminal "leader" peptides, which are strikingly basic in overall amino acid composition. Recent experiments indicate that these leader peptides are both necessary and sufficient to direct post-translational recognition and import of precursors by mitochondria. In this report, we demonstrate a critical role for one or more of the basic arginine residues in the leader peptide of the subunit precursor for the human mitochondrial matrix enzyme, ornithine transcarbamoylase (ornithine carbamoyltransferase, carbamoylphosphate: L-ornithine carbamoyltransferase, EC 2.1.3.3). The distal three of four basic residues, all arginines, in the leader peptide of ornithine transcarbamoylase were replaced at once with charge-neutral glycine residues. The altered ornithine transcarbamoylase precursor failed to be taken up by intact mitochondria in vitro. Moreover, it also failed to be proteolytically cleaved upon incubation with a mitochondrial matrix fraction containing the Zn2+-dependent protease, which normally cleaves the leader peptide.  相似文献   
8.
Background: Craniometric variation in humans reflects different genetic and environmental influences. Long-term climatic adaptation is less likely to show an impact on size and shape variation in a small local area than at the global level.

Aim: The aim of this work was to assess the contribution of the particular environmental factors to body height and craniofacial variability in a small geographic area of Croatia.

Subjects and methods: A total of 632 subjects, aged 18–21, participated in the survey. Body height, head length, head breadth, head height, head circumference, cephalic index, morphological face height, face breadth, and facial index were analysed regarding geographic, climatic and dietary conditions in different regions of the country, and correlated with the specific climatic variables (cumulative multiyear sunshine duration, cumulative multiyear average precipitation, multiyear average air temperatures) and calcium concentrations in drinking water. Significant differences between groups classified according to geographic, climatic or dietary affiliation, and the impact of the environmental predictors on the variation in the investigated traits were assessed using multiple forward stepwise regression analyses.

Results: Higher body height measures in both sexes were significantly correlated with Mediterranean diet type. Mediterranean diet type also contributed to higher head length and head circumference measures in females. Cephalic index values correlated to geographic regions in both sexes, showing an increase from southern to eastern Croatia. In the same direction, head length significantly decreased in males and head breadth increased in females. Mediterranean climate was associated with higher and narrower faces in females. The analysis of the particular climatic variables did not reveal a significant influence on body height in either sex. Concurrently, climatic features influenced all craniofacial traits in females and only head length and facial index in males. Mediterranean climate, characterized by higher average sunshine duration, higher average precipitation and higher average air temperatures, was associated with longer, higher and narrower skulls, higher head circumference, lower cephalic index, and higher and narrower faces (lower facial index). Calcium concentrations in drinking water did not correlate significantly with any dependent variable.

Conclusion: A significant effect of environmental factors on body height and craniofacial variability was found in Croatian young adult population. This effect was more pronounced in females, revealing sex-specific craniofacial differentiation. However, the impact of environment was low and may explain only 1.0–7.32% variation of the investigated traits.  相似文献   
9.
We have investigated the clonality of Ph1-negative hemopoietic progenitor cells appearing in long-term marrow cultures established with cells from a mosaic Turner syndrome patient (46,XX/45,X) with Ph1- positive chronic myeloid leukemia (CML). The Ph1-positive clone had been shown previously to have arisen from a cell of the 45,X lineage. At the time of the present study, the patient was five years post- diagnosis and had been off chemotherapy for two months following a year of treatment for lymphoid blast crisis. All analyzed unstimulated marrow metaphases and each of 23 individually analyzed erythroid and granulocyte colonies produced in assays of the starting marrow were 45,X,Ph1. Pooled granulocyte colonies from the same assays yielded four metaphases that were 45,X,Ph1 and one that was 46,XX. Very few hemopoietic progenitors were detected in long-term cultures at any time; however, all of four individually analyzed large granulocyte colonies and a pooled granulocyte colony preparation obtained from assays of 4- to 6-week-old adherent layers yielded exclusively 46,XX metaphases. These results provide evidence that non-clonal progenitors can persist in patients with CML, even after the onset and treatment of blast crisis, and that the long-term marrow culture system provides a sensitive method for detecting such cells.  相似文献   
10.
A critical step in the import of nuclear-encoded precursor proteins into mitochondria involves proteolytic cleavage of their amino-terminal leader peptides by processing proteases found in the mitochondrial matrix. We report here the characterization of the general matrix processing protease from rat liver mitochondria. The final enzyme preparation consisted of two polypeptides, a catalytically active 55-kDa subunit and a 52-kDa one. To deduce the complete primary structure of the 55-kDa subunit, we first sequenced its mature amino terminus and several tryptic peptides derived from the pure protein. Next, using mixed oligonucleotide primers that had sequences based on two of these peptides, we synthesized a partial cDNA probe by selective amplification of liver RNA with the polymerase chain reaction. The amplified probe was then used to obtain a nearly full-length clone from a rat liver cDNA library. This cDNA codes for 508 amino acid residues, including 16 residues of an amino-terminal leader peptide, the cleavage site of which is located two polypeptide bonds downstream from an arginine residue. The mature portion has a predicted molecular mass of 55.2 kDa; it shows 36% identity with the mitochondrial processing peptidases of Saccharomyces cerevisiae and Neurospora crassa. A conserved structural feature is a putative, negatively charged alpha-helix, located in the amino-terminal half of the subunit; this element might be important for the recognition of positively charged leader peptides characteristic of mitochondrial precursor proteins.  相似文献   
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