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11.
We present a case of obstructing calculi of the common bile duct diagnosed by ultrasonography. Postoperatively, a sterile abscess due to bile leakage at the distal common bile duct developed, and was also diagnosed by ultrasound Ultrasonography was useful in following the course of clearing of the bile collection. Preoperative ultrasound evaluation of the jaundiced patient should be followed by postoperative sonography, especially if complications occur. 相似文献
12.
Obstruction of the biliary tree by large amounts of mucinous material is reported in a patient with a mucin-producing cystic adenocarcinoma of the pancreas invading the common bile duct. Although preoperative endoscopic retrograde cholangiography suggested bile duct invasion, mucinous obstruction, as in the previous cases in which it has been reported, was not suspected. Mucinous obstruction, although unusual, should be considered in patients with cystic carcinomas of the pancreas in the presence of jaundice or episodes of cholangitis. 相似文献
13.
Arginine-insulin stimulation and IV glucose suppression (AIGT) tests were used to evaluate release of insulin and growth hormone. Adult patients responded normally. Hypopituitary patients showed no hGH response. One third of short normal patients showed abnormal hGH responses to glucose suppression. Two thirds of the short normal patients showed poor insulin responses to either amino acid or glucose stimulation. Such patients might have abnormalities in release mechanisms for insulin and suppression mechanisms for hGH and this might contribute to their growth failure. 相似文献
14.
RM Gipstein JW Coburn DA Adams DB Lee KP Parsa A Sellers WN Suki SG Massry 《Canadian Metallurgical Quarterly》1976,136(11):1273-1280
Eleven patients with chronic renal failure and presumed secondary hyperparathyroidism developed a syndrome of medial calcinosis of the arteries and painful ischemic ulcers of the fingers, legs, or thighs, or any combination of the three. Five patients required maintenance hemodialysis; six had functioning renal homografts. Severe hyperphosphatemia had existed in each; seven showed roentgenographic evidence of subperiosteal resorption. Similarities are evident between the lesions and experimentally produced calciphylaxix. The lesions demonstrated a relentless, progressive course, with serious morbidity and mortality. Hyperplastic or adenomatours parathyroid tissue was removed from ten of 11 patients unergoing surgical procedures; healing followed in seven patients. Treatment with phosphate-binding antacids to lower serum phosphorus levels may prevent this syndrome. Total or subtotal parathyroidectomy should be considered when ischemic skin lesions appear in uremic patients or in renal transplant recipients. 相似文献
15.
DB McClelland 《Canadian Metallurgical Quarterly》1976,5(8):909-915
The synthesis of immunoglobulins G, A, and M has been studied in Peyer's patches together with closely associated intestinal mucosa and in small intestine distant from Peyer's patches in specific-pathogen-free (SPF) Swiss mice and conventional and germ-free C3H mice. Thissue fragments were cultured in vitro in medium containing 14C-labelled amino acids, and newly synthesized proteins were detected by radioimmunoelectrophoresis. Small intestine from SPF and conventional animals synthesized almost exclusively IgA. No immunoglobulin synthesis was detectable in germ-free intestine. In contrast, the Peyer's patches and associated mucosa of all the groups of mice synthesized IgG, IgA, and IgM. This observation is discussed in relation to the possible role of the Peyer's patches as a source of precursors for immunoglobulin-producing cells in the intestine. 相似文献
16.
17.
Molecular modeling of immunoglobulin light chains implicates hydrophobic residues in non-amyloid light chain deposition disease 总被引:3,自引:0,他引:3
Deret S; Chomilier J; Huang DB; Preud'homme JL; Stevens FJ; Aucouturier P 《Protein engineering, design & selection : PEDS》1997,10(10):1191-1197
Light chain deposition disease is a severe complication of certain
immunoproliferative disorders, due to the secretion of a monoclonal light
chain which precipitates close to basement membranes of several tissues. A
kappa isotype restriction and an unusual frequency of a variable region
subgroup (VkappaIV) suggest that precise structural features govern the
propensity of pathogenic light chains to precipitate in extracellular
spaces. We studied primary structures of light chains from six patients
with light chain deposition disease in comparison with light chains from
other pathological conditions. Sequence alignment revealed the presence of
certain amino acids only in light chain deposition disease, in particular
non-polar replacing hydrophilic residues. To determine the role of these
residues, structures of the variable domain from four kappa chains
belonging to VkappaI and VkappaIV subgroups responsible for deposition
disease were modeled using known immunoglobulins as templates. The most
evident structural features shared by all pathogenic light chains were
hydrophobic residues exposed to the solvent in complementarity determining
regions 1 or 3. In contrast to immunoglobulin light chain- related
amyloidosis, where deposition of organized material might be due to
electrostatic interactions between light chain dimers, hydrophobic
interactions could enhance amorphous precipitation in non- amyloid light
chain deposition disease.
相似文献
18.
1. The erythrocyte content of sodium and of potassium were measured in 231 unselected patients with hypokalaemia, and together with net ouabain-sensitive sodium efflux in patients with severe hypokalaemia, before (20 patients) and during potassium repletion (14 patients). 2. The erythrocytes of the patients with hypokalaemia compared with control subjects had on average an increase in sodium content, a decrease in potassium content and a reduction in the rate constant of ouabain-sensitive sodium efflux. All three changes had a similar curvilinear relation to the concentration of potassium in plasma with relatively little change in the measured variable unless the plasma potassium was very low. 3. There was a similar curvilinear relation between the final sodium and potassium content of normal erythrocytes and the potassium concentration of the medium in which they were incubated for 48 h in vitro. 4. These results suggest that the changes in the sodium and potassium content of erythrocytes in hypokalaemia are due to a direct inhibiting effect of the hypokalaemia on the activity of the sodium pump. 5. In many patients with hypokalaemia of moderate degree the increase in erythrocyte sodium content was less than expected from the effect in vitro of a low extracellular potassium concentration. This finding suggests that a compensatory change, presumably an increase in the number of sodium pumps, is a common event even in moderate hypokalaemia. 相似文献
19.
Two models of the action of uncoupler molecules in inhibiting photophosphorylation in bacterial chromatophores are considered: either uncoupler molecules shuttle rapidly between energy-coupling sites, or uncoupler molecules that are bound to particular sites in the chromatophores for a time that is comparable with the turnover time of the photophosphorylation apparatus may uncouple by a co-operative "substoichiometric' mechanism. It is found that the titre of uncoupler necessary to cause complete uncoupling is lowered if the rate of photophosphorylation is initially decreased by partially restricting electron flow with an appropriate titre of antimycin A. This result indicates that uncoupler molecules shuttle rapidly between energy coupling in which the energized intermediate between electron transport and phosphorylation is delocalized over the entire chromatophore membrane and those in which it is not. If the rate of photophosphorylation is partially restricted with the covalent H+-translocating ATP synthase inhibitor dicyclohexylcarbodi-imide, the titre of uncoupler necessary to effect complete inhibition of photophosphorylation is also decreased relative to that in which the covalent H+-ATP synthase inhibitor is absent. This important result appears to be inconsistent with models of electron-transport phosphorylation in which the "energized state' of the chromatophore membrane that is set up by electron transport and utilized in photophosphorylation is delocalized over the entire chromatophore membrane. 相似文献
20.
DB Glazier JL Marmar E Mayer M Gibbs SL Corson 《Canadian Metallurgical Quarterly》1999,161(2):463-466
PURPOSE: Intraoperative sperm banking has been recommended during vasectomy reversal. These specimens are maintained as insurance for possible future intracytoplasmic sperm injection. We evaluated the fate of specimens collected intraoperatively from 48 vasectomy reversal patients. MATERIALS AND METHODS: Of 75 men 48 (64.0%) agreed to intraoperative sperm banking during vasectomy reversal. A total of 135 vials of epididymal sperm, 81 vials of testicular tissue and 13 vials of vasal sperm were cryopreserved. RESULTS: Among couples who stored sperm 10 (20.8%) voluntarily discarded the specimens within 4 months of vasectomy reversal. Specimens from 31 couples (64.5%) remain in storage. Seven couples (14.6%) have used frozen sperm for intracytoplasmic sperm injection. In 3 of these couples the men were azoospermic after surgery, 2 men had 10,000 to 15,000 sperm per ml. in the ejaculate with limited motility and 2 had 1 to 2 million sperm per ml. with limited motility. The 7 women who underwent intracytoplasmic sperm injection ranged between 37 and 39 years old, which was older than the mean age of the remaining study group (32.7 years). With intracytoplasmic sperm injection fertilization was achieved in all cases and 20 of 47 eggs (42.5%) developed into embryos. Of 7 women 4 achieved biochemical pregnancies (57.1%) and 2 (28.6%) delivered newborns with epididymal sperm. Natural pregnancy occurred in 7 of 16 vasectomy reversal couples (43.7%) who were followed at least 18 months postoperatively but the time to pregnancy averaged 1 year. CONCLUSIONS: Cryopreservation of sperm collected at vasectomy reversal is recommended for patients undergoing vasoepididymostomy or vasovasostomy. The couples who used the cryopreserved sperm for intracytoplasmic sperm injection included husbands whose postoperative ejaculate remained azoospermic or severely oligospermic and wives who were approaching 40 years old. Only a limited number of couples (14.6% of the study group) have used the cryopreserved sperm but the delivered newborn rate (28.6%) was comparable to other intracytoplasmic sperm injection data. The natural pregnancy rate after vasectomy reversal was 43.7% but the time to pregnancy after surgery was lengthy (average 1 year). These findings may be helpful for counseling couples who are planning vasectomy reversal surgery and may be considering intraoperative sperm banking. 相似文献