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151.
Tumor cells from eight adult patients with T-cell chronic malignancies were investigated with a series of monoclonal antibodies recognizing T-cell differentiation antigens. This series allowed definition of discrete subpopulations of mature T cells with functional specialization. All six patients with Sézary syndrome and one patient with T-chronic lymphocytic leukemia had cells with the same phenotype as normal helper/inducer T cells, whereas the other patient with T-chronic lymphocytic leukemia had cell with the same phenotype as normal cytotoxic/suppressor T cells. Some clinical manifestations observed in these patients may reflect retention of functional activities by their malignant cells.  相似文献   
152.
Discussion of pain problems in persons with AIDS has been limited in medical and nursing literature, yet pain is a major source of suffering and concern for patients. Common pain characteristics are described in 100 persons with CDC-defined AIDS, using the 1987 definition. The two most frequently cited types of pain for both drugs users and nondrug users with AIDS were abdominal pain and neuropathic pain. Drug users experienced pain due to esophagitis and headaches more frequently than nondrug users, while nondrug users experienced Kaposi's sarcoma-related pain more often. Treatment responses were individualized, with drug users requiring more frequent use of opiates. General treatment strategies are suggested with special emphasis on the unique needs of PWAs.  相似文献   
153.
Serine 167 has been identified by radiolabel and amino acid sequencing as the major estrogen-induced phosphorylation site on the human estrogen receptor (hER) from human MCF-7 mammary carcinoma cells. The phosphorylation of the hER on serine 167 was estrogen-dependent, increasing 4-fold upon estradiol treatment of MCF-7 cells and accounted for almost half of the total [32P]phosphate incorporated into the recombinant hER from Sf9 insect cells and the native hER from MCF-7 cells. Casein kinase II was found to phosphorylate the purified recombinant hER on serine 167 in vitro. In addition, estradiol binding enhanced by 2-fold the phosphorylation of the purified recombinant hER by casein kinase II in vitro. Western blot analysis and [32P]phosphate incorporation confirmed the presence of casein kinase II in Sf9 cells. These results demonstrate that the hER is phosphorylated on serine 167 by casein kinase II in a hormone-dependent manner.  相似文献   
154.
The vascular anatomy of the posterior tibial vessels has been studied in 20 legs of 10 cadavers. The number, size and distribution of the direct cutaneous and direct muscle branches of the posterior tibial vessels were recorded. For analysis, the leg was divided into four equal segments, Zone I being the most distal and Zone IV the most proximal. The direct cutaneous branches were found to cluster mainly around Zone II. The direct muscle branches to the soleus and flexor digitorum longus muscles arose chiefly in Zones II and III. Based on this knowledge, we performed fasciocutaneous, island soleus muscle, musculo-fasciocutaneous and flexor digitorum longus muscle flaps based on the posterior tibial vessels in 12 patients. Four were free fasciocutaneous flaps and eight were pedicled flaps. All flaps survived and there were no major complications. Delayed wound healing was encountered in three patients.  相似文献   
155.
We developed gas chromatography-mass spectrometric methods for assaying the enrichment of 99 at.% [6,6-2H2]glucose and 30 at.% [U-13C6]glucose, although both tracers are mostly M + 2. 13C enrichment is determined either by the C-1 to C-5 fragment of glucose aldonitrile pentaacetate or by oxidation of glucose to glucarate. 2H enrichment is assayed as the difference between the 13C enrichment of glucarate and the 2H + 13C enrichment of glucose. The techniques, which were validated in in vivo experiments, are applicable to the determination of simultaneous or sequential measurements of the rate of glucose appearance before and after an intervention. They could also be applied to the simultaneous determination of (i) gluconeogenesis by incorporation of a 13C-labeled precursor into glucose and (ii) the rate of glucose appearance by [6,6-2H2]glucose infusion.  相似文献   
156.
OBJECTIVE: To assess the respective roles of general pediatricians and pediatric subspecialists in the provision of primary pediatric care. DESIGN AND METHODS: A practice characteristics questionnaire that included questions about primary care was sent to a random sample of 1616 board-certified and board-eligible active Fellows of the American Academy of Pediatrics; 1145 (70.9%) responded. Analyses pertain to those pediatricians who provided ambulatory patient care and were not in graduate medical education training at the time of the survey. Respondents were divided into 2 groups for purposes of analysis: the 527 pediatricians whose practice was primarily in general pediatrics (defined as 80% of time spent in general pediatrics or any time spent in adolescent medicine) and the 213 pediatricians whose practice was subspecialty focused (all others). These groups were then further stratified according to whether they provided primary care. The resultant subgroups contained 518 general pediatricians and 98 subspecialists who provided primary care. RESULTS: Among the entire sample, general pediatricians indicated that general pediatricians provide 93% of the primary care delivered by their practice and that pediatric subspecialists provide 2% of the primary care. In contrast, pediatric subspecialists reported that general pediatricians provide 53% of the primary care delivered by their practice and that subspecialists provide 32% of such care (P<.001). Among the subsample of pediatricians who provide primary care, general pediatricians reported delivering 88% of the primary care received by their patients and subspecialists reported delivering 74% of the primary care received by their patients (P<.001). CONCLUSION: Perspectives on the degree to which pediatric subspecialists provide primary pediatric care vary depending on generalist vs subspecialist self-identification.  相似文献   
157.
Clinically apparent thyroid nodules occur in about 5 percent of the population. Because most patients with thyroid nodules present initially to their primary care physician, family physicians should have a thorough understanding of the diagnosis and treatment of thyroid nodules. The history and physical examination may be helpful in detecting thyroid nodules but are not useful in predicting malignancy. Furthermore, laboratory studies, ultrasonography and nuclear medicine scans do not reliably differentiate between benign and malignant thyroid nodules. In most cases, fine-needle aspiration biopsy can accurately identify malignant thyroid nodules. Fine-needle aspiration biopsy is safe and can be performed in an office setting.  相似文献   
158.
The comparative efficiency of 5 standard technics for the detection of feline liver fluke ova in feces was evaluated. The formalin-ether technic proved superior to direct smear, sugar flotation, zinc sulfate flotation, or detergent sedimentation technics. The formalin-ether technic correctly diagnosed all Platynosomum concinnum-infected cats studied, as confirmed by necropsy findings.  相似文献   
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