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691.
BACKGROUND: The development of user-friendly laboratory analyzers, combined with the need for rapid assessment of critically ill patients, has led to the performance of in vitro diagnostic testing at the point of care by personnel without formal laboratory training. OBJECTIVES: To determine the range of laboratory testing performed by critical care nurses and their attitudes toward this role. METHODS: A survey of critical care nursing consultants was conducted, using a modified Likert scale, to assess objective measures of point-of-care testing practice in critical care units and to determine nurses' attitudes toward the practice of point-of-care testing. Statistical analysis was performed to determine significant trends in responses. RESULTS: Of the units responding to the survey, 35% used critical care nurses exclusively to perform point-of-care testing, 32.5% used laboratory technicians and critical care nurses, and 25% used other personnel. Of critical care nurses performing laboratory testing, 95.5% performed blood glucose analysis; 18.7%, arterial blood gas analysis; 4.5%, electrolyte analysis; 4.5%, hematology profiles; and 22.7%, other testing. Most agreed that stat tests were not reported promptly, thereby necessitating bedside testing. Respondents indicated that they would prefer that laboratory personnel operate in vitro diagnostic equipment and that requirements for critical care nurses to perform laboratory testing detracted from other patient care duties. CONCLUSIONS: Most nurses who perform point-of-care testing responded that it was necessary and helpful in patient management. However, they would prefer, because of their other patient care responsibilities, that laboratory personnel take this responsibility.  相似文献   
692.
This study was planned to show the effect of retroperfusion and intraaortic balloon pumping (IABP) on myocardial hemodynamic recovery. Twelve dogs entered this study. Half of them received IABP and coronary sinus retroperfusion (CSPR) combination (Group II) and the remaining received IABP alone (Group I). Left anterior descending artery was occluded for a period of three hours. 15 minutes after occlusion IABP and IABP + CSRP were initiated. The average cardiac output was 1.41 +/- 0.18 L/min in the group I and 1.72 +/- 0.24 L/min in the group II (p < 0.03) after 3 hours of occlusion. Mean arterial pressure was 82.1 +/- 4.8 mmHg in the group I and 89.7 +/- 2.6 mmHg in the group II (p < 0.03). On the basis of this study it was concluded that CSRP + IABP could be an alternative treatment to IABP alone during the acutely developing ischemia.  相似文献   
693.
694.
Spermatozoa from oligozoospermic subjects are characterized by a reduced in vitro ability to penetrate hamster oocytes and by a decreased responsiveness to physiological stimuli that trigger the acrosome reaction. One of the first steps in the induction of the acrosome reaction is an increase of intracellular free calcium concentrations ([Ca2+]i). It has been recently shown that progesterone (P) is able to increase [Ca2+]i in capacitated human sperm at concentrations similar to those found in follicular fluid. We evaluated sperm [Ca2+]i increase in response to P (0.1 micrograms/ml) in 19 normo- and 17 oligozoospermic subjects. The average percentage of [Ca2+]i increase over the basal level was significantly lower in spermatozoa from oligozoospermic subjects when compared to normozoospermic subjects (138.7 +/- 8.22% increase in oligo- versus 263.3 +/- 39.7% increase in normozoospermic subjects; P < 0.001). Progesterone-stimulated [Ca2+]i increase was significantly correlated with sperm motility (r = 0.54), sperm concentration (r = 0.96), and sperm morphology (% of normal forms) (r = 0.49). In addition P induced a significant increase of acrosome-reacted spermatozoa in normospermic patients (n = 10), whereas no significant effect was observed in spermatozoa from oligozoospermic men (n = 7). Taken together, these results indicate that spermatozoa from oligozoospermic men have a reduced ability to initiate the cascade of events that lead to the acrosome reaction in response to a physiological stimulus, such as P, and might contribute to explaining the reduced fertilizing capacity of these patients.  相似文献   
695.
Choroidal nevi are found on routine fundus evaluations in 1% to 2% of patients. It is felt that these usually benign lesions are the precursors of choroidal malignant melanomas. The incidence of choroidal malignant melanoma in the United States is approximately 6 cases per 1 million persons per year. Diagnosis is multifactorial, based on the tumor's funduscopic, angiographic, and ultrasonographic appearance. Once a melanoma is diagnosed in a patient, a complete metastatic workup is performed. A small tumor is observed for change. Medium-sized tumors are treated with radioactive plaque therapy, external beam radiation, or enucleation. Large tumors are treated with enucleation with or without external beam radiation. Studies are underway to establish the optimum form of treatment.  相似文献   
696.
The method of cultivation of keratinocytes from burned patients allows obtaining a new type of wound coverings having advantages over those used at present in clinical practice. The use of autologous cell elements results in a rapid and perfect taking of the transplanted layers. The method allows a more rapid (3-4 weeks after trauma) and more efficient (the plasty coefficient 1:100 and more) recovery of the skin as compared with traditional methods of treatment. Long-term results of such plasty were satisfactory.  相似文献   
697.
The aim of this study was the evaluation of transesophageal echocardiography (TEE) in the detection of potential emboli sources of cardiac origin in a young population with cerebrovascular events, and to compare this study with transthoracic echocardiography (TE). We have studied 24 young subjects (average 33 years) and detected a potential cardiac source in 9 subjects, with transthoracic approach only in 4. We concluded that TEE is superior than TE to detect potential cardiac source of cerebral embolism. The most frequently abnormality was mitral valve prolapse.  相似文献   
698.
UV-B irradiation (700 J/m2) of bone marrow cells (BMC) before transplantation into lethally irradiated (1050R) allogeneic rats prevents graft-versus-host disease (GVHD) and results in stable chimerism. This study examined whether UV-B modulation of BMT is useful in the subsequent induction of tolerance to small bowel transplant (SBT) and avoids the danger of GVHD, which remains the major obstacle to successful SBT. Lethally irradiated Lewis recipients of UV-B irradiated (700 J/m2) BMT (10(8) BMC admixed with 5 x 10(6) splenic leukocytes) either from ACI or Wistar-Furth (WF) rats developed stable chimerism without any evidence of GVHD for > 360 days. Lewis recipients of UV-B ACI BMC expressed 95 +/- 6% ACI lymphoid cells at 50 and 150 days after BMT using complement-dependent cytotoxicity assay. Unmodified Lewis recipients of orthotopic ACI SBT rejected their grafts and died in 7-9 days, whereas Lewis chimeras accepted permanently (> 200 days) bone marrow donor (ACI) SBT without any evidence of GVHD when the SBT was performed at 60 or 150 days after BMT. In contrast, when SBT was performed, only 30 days after induction of chimerism with UV-B ACI BMT, the recipients developed severe GVHD and died between 17 and 21 days. The Lewis chimeras rejected third part (WF) SBT acutely and died in 7-9 days, thus demonstrating the specificity of the induction of tolerance in this model. That this immunologic unresponsiveness is not restricted by the recipient-donor rat strain combination was shown by the permanent acceptance of WF SBT without GVHD by Lewis/WF chimeric recipients. Furthermore, the Lewis chimeras that were made diabetic with STZ 28 days after BMT permanently accepted (> 300 days) BM donor-type (WF) and recipient-type (Lewis) islet cells and became normoglycemic, thus indicating tolerance to both donor and recipient Ags. The diabetic Lewis chimeras that became normoglycemic permanently accepted (> 200 days) WF SBT without any evidence of GVHD after donor-type SBT 110 days after WF islet transplantation. The apparent lack of organ-specific unresponsiveness in this model confirmed our previous observation with combined islet and heart transplants. In vitro MLR studies showed that the chimeric animals were specifically unreactive to donor- and recipient-type alloantigens. Our results demonstrate that UV-B irradiation of BMT is a promising approach to the induction of tolerance to SBT.  相似文献   
699.
No epidemiological typing system to differentiate among Pseudomonas pseudomallei isolates has been available. Ribotype analysis was developed and used to examine 74 clinical and 10 environmental isolates of P. pseudomallei from Thailand. Six P. pseudomallei ribotypes were identified from restriction fragment polymorphisms of EcoRI chromosomal digests. The predominant ribotype, A, was found in 59 of the isolates examined. By using patterns from hybridizations with SalI, HindIII, and PstI restriction digests, isolates of ribotype A were subdivided into a further five subtypes, giving a total of 10 differentiable P. pseudomallei types. In 23 of 34 melioidosis patients studied, multiple P. pseudomallei isolates were present. In all but one of these patients, a single ribotype of the organism was present. Isolation of two different ribotypes of P. pseudomallei from one patient, one each in sputum and urine, suggests that superinfection may have occurred. The ribotype was shown to be conserved during the course of antibiotic treatments in seven patients studied, although the antibiotic sensitivity patterns in the isolates from these patients varied. The prevalence of subtype A1 in clinical and environmental specimens suggests that this strain may be predominant in this geographical location. These results demonstrate the usefulness of the ribotyping method for epidemiological studies of P. pseudomallei.  相似文献   
700.
Recent evidence suggests that polymorphonuclear leukocyte (PMN) elastase causes tissue injury in a variety of diseases. Current methods of purification of elastase involve several steps which result in a low yield. We report a simple purification method. PMN (10(9) in 4 ml of 0.05 M Tris, pH 7.8, containing 0.2% Triton X-100 were disrupted and homogenized by freezing and thawing followed by sonication. After centrifugation at 100,000 g for 20 min, enzyme was extracted from the pellet with 2.5 ml of 0.05 M Tris/1M NaCl (pH 7.8). The centrifugation-extraction cycle was repeated 3 times. Elastase from 10(8) PMN was then purified using a 1 ml Protease Inhibitor Affinity-Filter prepared by binding benzamidine to silica. Enzyme activity was determined by cleavage of the synthetic substrate N-Suc-(Ala)3-pNa. SDS-PAGE demonstrated 2 polypeptides, molecular masses of 29 and 27 kD with amino acid composition and partial N-terminal sequence (Ile-Val-Gly-Gly-Arg-Arg-Ala-Arg-Pro-His-Ala-Trp-Pro-) identical with those previously reported for elastase. We obtained 50 micrograms elastase (34-fold purification) with specific activity of 52 U/mg/min from 10(8) PMN. This represents a much greater recovery (23% yield) than is achieved by other methods. This method is simple, highly reproducible, and can be performed within a 2-day period.  相似文献   
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